1 files changed, 6121 insertions, 0 deletions
diff --git a/contrib/SDL-3.2.8/include/SDL3/SDL_stdinc.h b/contrib/SDL-3.2.8/include/SDL3/SDL_stdinc.h
new file mode 100644
index 0000000..9903a0b
--- /dev/null
+++ b/contrib/SDL-3.2.8/include/SDL3/SDL_stdinc.h
@@ -0,0 +1,6121 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2025 Sam Lantinga <slouken@libsdl.org>
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+/**
+ * # CategoryStdinc
+ *
+ * SDL provides its own implementation of some of the most important C runtime
+ * functions.
+ *
+ * Using these functions allows an app to have access to common C
+ * functionality without depending on a specific C runtime (or a C runtime at
+ * all). More importantly, the SDL implementations work identically across
+ * platforms, so apps can avoid surprises like snprintf() behaving differently
+ * between Windows and Linux builds, or itoa() only existing on some
+ * platforms.
+ *
+ * For many of the most common functions, like SDL_memcpy, SDL might just call
+ * through to the usual C runtime behind the scenes, if it makes sense to do
+ * so (if it's faster and always available/reliable on a given platform),
+ * reducing library size and offering the most optimized option.
+ *
+ * SDL also offers other C-runtime-adjacent functionality in this header that
+ * either isn't, strictly speaking, part of any C runtime standards, like
+ * SDL_crc32() and SDL_reinterpret_cast, etc. It also offers a few better
+ * options, like SDL_strlcpy(), which functions as a safer form of strcpy().
+ */
+#ifndef SDL_stdinc_h_
+#define SDL_stdinc_h_
+#include <SDL3/SDL_platform_defines.h>
+#include <stdarg.h>
+#include <stdint.h>
+#include <string.h>
+#include <wchar.h>
+#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) || \
+    defined(SDL_INCLUDE_INTTYPES_H)
+#include <inttypes.h>
+#endif
+#ifndef __cplusplus
+#if defined(__has_include) && !defined(SDL_INCLUDE_STDBOOL_H)
+#if __has_include(<stdbool.h>)
+#define SDL_INCLUDE_STDBOOL_H
+#endif
+#endif
+#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) || \
+    (defined(_MSC_VER) && (_MSC_VER >= 1910 /* Visual Studio 2017 */)) || \
+    defined(SDL_INCLUDE_STDBOOL_H)
+#include <stdbool.h>
+#elif !defined(__bool_true_false_are_defined) && !defined(bool)
+#define bool  unsigned char
+#define false 0
+#define true  1
+#define __bool_true_false_are_defined 1
+#endif
+#endif /* !__cplusplus */
+#ifndef SDL_DISABLE_ALLOCA
+# ifndef alloca
+#  ifdef HAVE_ALLOCA_H
+#   include <alloca.h>
+#  elif defined(SDL_PLATFORM_NETBSD)
+#   if defined(__STRICT_ANSI__)
+#    define SDL_DISABLE_ALLOCA
+#   else
+#    include <stdlib.h>
+#   endif
+#  elif defined(__GNUC__)
+#   define alloca __builtin_alloca
+#  elif defined(_MSC_VER)
+#   include <malloc.h>
+#   define alloca _alloca
+#  elif defined(__WATCOMC__)
+#   include <malloc.h>
+#  elif defined(__BORLANDC__)
+#   include <malloc.h>
+#  elif defined(__DMC__)
+#   include <stdlib.h>
+#  elif defined(SDL_PLATFORM_AIX)
+# pragma alloca
+#  elif defined(__MRC__)
+void *alloca(unsigned);
+#  else
+void *alloca(size_t);
+#  endif
+# endif
+#endif
+#ifdef SDL_WIKI_DOCUMENTATION_SECTION
+/**
+ * Don't let SDL use "long long" C types.
+ *
+ * SDL will define this if it believes the compiler doesn't understand the
+ * "long long" syntax for C datatypes. This can happen on older compilers.
+ *
+ * If _your_ compiler doesn't support "long long" but SDL doesn't know it, it
+ * is safe to define this yourself to build against the SDL headers.
+ *
+ * If this is defined, it will remove access to some C runtime support
+ * functions, like SDL_ulltoa and SDL_strtoll that refer to this datatype
+ * explicitly. The rest of SDL will still be available.
+ *
+ * SDL's own source code cannot be built with a compiler that has this
+ * defined, for various technical reasons.
+ */
+#define SDL_NOLONGLONG 1
+#elif defined(_MSC_VER) && (_MSC_VER < 1310)  /* long long introduced in Visual Studio.NET 2003 */
+#  define SDL_NOLONGLONG 1
+#endif
+#ifdef SDL_WIKI_DOCUMENTATION_SECTION
+/**
+ * The largest value that a `size_t` can hold for the target platform.
+ *
+ * `size_t` is generally the same size as a pointer in modern times, but this
+ * can get weird on very old and very esoteric machines. For example, on a
+ * 16-bit Intel 286, you might have a 32-bit "far" pointer (16-bit segment
+ * plus 16-bit offset), but `size_t` is 16 bits, because it can only deal with
+ * the offset into an individual segment.
+ *
+ * In modern times, it's generally expected to cover an entire linear address
+ * space. But be careful!
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_SIZE_MAX SIZE_MAX
+#elif defined(SIZE_MAX)
+# define SDL_SIZE_MAX SIZE_MAX
+#else
+# define SDL_SIZE_MAX ((size_t) -1)
+#endif
+#ifndef SDL_COMPILE_TIME_ASSERT
+#ifdef SDL_WIKI_DOCUMENTATION_SECTION
+/**
+ * A compile-time assertion.
+ *
+ * This can check constant values _known to the compiler at build time_ for
+ * correctness, and end the compile with the error if they fail.
+ *
+ * Often times these are used to verify basic truths, like the size of a
+ * datatype is what is expected:
+ *
+ * ```c
+ * SDL_COMPILE_TIME_ASSERT(uint32_size, sizeof(Uint32) == 4);
+ * ```
+ *
+ * The `name` parameter must be a valid C symbol, and must be unique across
+ * all compile-time asserts in the same compilation unit (one run of the
+ * compiler), or the build might fail with cryptic errors on some targets.
+ * This is used with a C language trick that works on older compilers that
+ * don't support better assertion techniques.
+ *
+ * If you need an assertion that operates at runtime, on variable data, you
+ * should try SDL_assert instead.
+ *
+ * \param name a unique identifier for this assertion.
+ * \param x the value to test. Must be a boolean value.
+ *
+ * \threadsafety This macro doesn't generate any code to run.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ *
+ * \sa SDL_assert
+ */
+#define SDL_COMPILE_TIME_ASSERT(name, x) FailToCompileIf_x_IsFalse(x)
+#elif defined(__cplusplus)
+/* Keep C++ case alone: Some versions of gcc will define __STDC_VERSION__ even when compiling in C++ mode. */
+#if (__cplusplus >= 201103L)
+#define SDL_COMPILE_TIME_ASSERT(name, x)  static_assert(x, #x)
+#endif
+#elif defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 202311L)
+#define SDL_COMPILE_TIME_ASSERT(name, x)  static_assert(x, #x)
+#elif defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 201112L)
+#define SDL_COMPILE_TIME_ASSERT(name, x) _Static_assert(x, #x)
+#endif
+#endif /* !SDL_COMPILE_TIME_ASSERT */
+#ifndef SDL_COMPILE_TIME_ASSERT
+/* universal, but may trigger -Wunused-local-typedefs */
+#define SDL_COMPILE_TIME_ASSERT(name, x)               \
+       typedef int SDL_compile_time_assert_ ## name[(x) * 2 - 1]
+#endif
+/**
+ * The number of elements in a static array.
+ *
+ * This will compile but return incorrect results for a pointer to an array;
+ * it has to be an array the compiler knows the size of.
+ *
+ * This macro looks like it double-evaluates the argument, but it does so
+ * inside of `sizeof`, so there are no side-effects here, as expressions do
+ * not actually run any code in these cases.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_arraysize(array) (sizeof(array)/sizeof(array[0]))
+/**
+ * Macro useful for building other macros with strings in them.
+ *
+ * For example:
+ *
+ * ```c
+ * #define LOG_ERROR(X) OutputDebugString(SDL_STRINGIFY_ARG(__FUNCTION__) ": " X "\n")`
+ * ```
+ *
+ * \param arg the text to turn into a string literal.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_STRINGIFY_ARG(arg)  #arg
+/**
+ *  \name Cast operators
+ *
+ *  Use proper C++ casts when compiled as C++ to be compatible with the option
+ *  -Wold-style-cast of GCC (and -Werror=old-style-cast in GCC 4.2 and above).
+ */
+/* @{ */
+#ifdef SDL_WIKI_DOCUMENTATION_SECTION
+/**
+ * Handle a Reinterpret Cast properly whether using C or C++.
+ *
+ * If compiled as C++, this macro offers a proper C++ reinterpret_cast<>.
+ *
+ * If compiled as C, this macro does a normal C-style cast.
+ *
+ * This is helpful to avoid compiler warnings in C++.
+ *
+ * \param type the type to cast the expression to.
+ * \param expression the expression to cast to a different type.
+ * \returns `expression`, cast to `type`.
+ *
+ * \threadsafety It is safe to call this macro from any thread.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ *
+ * \sa SDL_static_cast
+ * \sa SDL_const_cast
+ */
+#define SDL_reinterpret_cast(type, expression) reinterpret_cast<type>(expression)  /* or `((type)(expression))` in C */
+/**
+ * Handle a Static Cast properly whether using C or C++.
+ *
+ * If compiled as C++, this macro offers a proper C++ static_cast<>.
+ *
+ * If compiled as C, this macro does a normal C-style cast.
+ *
+ * This is helpful to avoid compiler warnings in C++.
+ *
+ * \param type the type to cast the expression to.
+ * \param expression the expression to cast to a different type.
+ * \returns `expression`, cast to `type`.
+ *
+ * \threadsafety It is safe to call this macro from any thread.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ *
+ * \sa SDL_reinterpret_cast
+ * \sa SDL_const_cast
+ */
+#define SDL_static_cast(type, expression) static_cast<type>(expression)  /* or `((type)(expression))` in C */
+/**
+ * Handle a Const Cast properly whether using C or C++.
+ *
+ * If compiled as C++, this macro offers a proper C++ const_cast<>.
+ *
+ * If compiled as C, this macro does a normal C-style cast.
+ *
+ * This is helpful to avoid compiler warnings in C++.
+ *
+ * \param type the type to cast the expression to.
+ * \param expression the expression to cast to a different type.
+ * \returns `expression`, cast to `type`.
+ *
+ * \threadsafety It is safe to call this macro from any thread.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ *
+ * \sa SDL_reinterpret_cast
+ * \sa SDL_static_cast
+ */
+#define SDL_const_cast(type, expression) const_cast<type>(expression)  /* or `((type)(expression))` in C */
+#elif defined(__cplusplus)
+#define SDL_reinterpret_cast(type, expression) reinterpret_cast<type>(expression)
+#define SDL_static_cast(type, expression) static_cast<type>(expression)
+#define SDL_const_cast(type, expression) const_cast<type>(expression)
+#else
+#define SDL_reinterpret_cast(type, expression) ((type)(expression))
+#define SDL_static_cast(type, expression) ((type)(expression))
+#define SDL_const_cast(type, expression) ((type)(expression))
+#endif
+/* @} *//* Cast operators */
+/**
+ * Define a four character code as a Uint32.
+ *
+ * \param A the first ASCII character.
+ * \param B the second ASCII character.
+ * \param C the third ASCII character.
+ * \param D the fourth ASCII character.
+ * \returns the four characters converted into a Uint32, one character
+ *          per-byte.
+ *
+ * \threadsafety It is safe to call this macro from any thread.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_FOURCC(A, B, C, D) \
+    ((SDL_static_cast(Uint32, SDL_static_cast(Uint8, (A))) << 0) | \
+     (SDL_static_cast(Uint32, SDL_static_cast(Uint8, (B))) << 8) | \
+     (SDL_static_cast(Uint32, SDL_static_cast(Uint8, (C))) << 16) | \
+     (SDL_static_cast(Uint32, SDL_static_cast(Uint8, (D))) << 24))
+#ifdef SDL_WIKI_DOCUMENTATION_SECTION
+/**
+ * Append the 64 bit integer suffix to a signed integer literal.
+ *
+ * This helps compilers that might believe a integer literal larger than
+ * 0xFFFFFFFF is overflowing a 32-bit value. Use `SDL_SINT64_C(0xFFFFFFFF1)`
+ * instead of `0xFFFFFFFF1` by itself.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ *
+ * \sa SDL_UINT64_C
+ */
+#define SDL_SINT64_C(c)  c ## LL  /* or whatever the current compiler uses. */
+/**
+ * Append the 64 bit integer suffix to an unsigned integer literal.
+ *
+ * This helps compilers that might believe a integer literal larger than
+ * 0xFFFFFFFF is overflowing a 32-bit value. Use `SDL_UINT64_C(0xFFFFFFFF1)`
+ * instead of `0xFFFFFFFF1` by itself.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ *
+ * \sa SDL_SINT64_C
+ */
+#define SDL_UINT64_C(c)  c ## ULL /* or whatever the current compiler uses. */
+#else /* !SDL_WIKI_DOCUMENTATION_SECTION */
+#ifndef SDL_SINT64_C
+#if defined(INT64_C)
+#define SDL_SINT64_C(c)  INT64_C(c)
+#elif defined(_MSC_VER)
+#define SDL_SINT64_C(c)  c ## i64
+#elif defined(__LP64__) || defined(_LP64)
+#define SDL_SINT64_C(c)  c ## L
+#else
+#define SDL_SINT64_C(c)  c ## LL
+#endif
+#endif /* !SDL_SINT64_C */
+#ifndef SDL_UINT64_C
+#if defined(UINT64_C)
+#define SDL_UINT64_C(c)  UINT64_C(c)
+#elif defined(_MSC_VER)
+#define SDL_UINT64_C(c)  c ## ui64
+#elif defined(__LP64__) || defined(_LP64)
+#define SDL_UINT64_C(c)  c ## UL
+#else
+#define SDL_UINT64_C(c)  c ## ULL
+#endif
+#endif /* !SDL_UINT64_C */
+#endif /* !SDL_WIKI_DOCUMENTATION_SECTION */
+/**
+ *  \name Basic data types
+ */
+/* @{ */
+/**
+ * A signed 8-bit integer type.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+typedef int8_t Sint8;
+#define SDL_MAX_SINT8   ((Sint8)0x7F)           /* 127 */
+#define SDL_MIN_SINT8   ((Sint8)(~0x7F))        /* -128 */
+/**
+ * An unsigned 8-bit integer type.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+typedef uint8_t Uint8;
+#define SDL_MAX_UINT8   ((Uint8)0xFF)           /* 255 */
+#define SDL_MIN_UINT8   ((Uint8)0x00)           /* 0 */
+/**
+ * A signed 16-bit integer type.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+typedef int16_t Sint16;
+#define SDL_MAX_SINT16  ((Sint16)0x7FFF)        /* 32767 */
+#define SDL_MIN_SINT16  ((Sint16)(~0x7FFF))     /* -32768 */
+/**
+ * An unsigned 16-bit integer type.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+typedef uint16_t Uint16;
+#define SDL_MAX_UINT16  ((Uint16)0xFFFF)        /* 65535 */
+#define SDL_MIN_UINT16  ((Uint16)0x0000)        /* 0 */
+/**
+ * A signed 32-bit integer type.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+typedef int32_t Sint32;
+#define SDL_MAX_SINT32  ((Sint32)0x7FFFFFFF)    /* 2147483647 */
+#define SDL_MIN_SINT32  ((Sint32)(~0x7FFFFFFF)) /* -2147483648 */
+/**
+ * An unsigned 32-bit integer type.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+typedef uint32_t Uint32;
+#define SDL_MAX_UINT32  ((Uint32)0xFFFFFFFFu)   /* 4294967295 */
+#define SDL_MIN_UINT32  ((Uint32)0x00000000)    /* 0 */
+/**
+ * A signed 64-bit integer type.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ *
+ * \sa SDL_SINT64_C
+ */
+typedef int64_t Sint64;
+#define SDL_MAX_SINT64  SDL_SINT64_C(0x7FFFFFFFFFFFFFFF)   /* 9223372036854775807 */
+#define SDL_MIN_SINT64  ~SDL_SINT64_C(0x7FFFFFFFFFFFFFFF)  /* -9223372036854775808 */
+/**
+ * An unsigned 64-bit integer type.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ *
+ * \sa SDL_UINT64_C
+ */
+typedef uint64_t Uint64;
+#define SDL_MAX_UINT64  SDL_UINT64_C(0xFFFFFFFFFFFFFFFF)   /* 18446744073709551615 */
+#define SDL_MIN_UINT64  SDL_UINT64_C(0x0000000000000000)   /* 0 */
+/**
+ * SDL times are signed, 64-bit integers representing nanoseconds since the
+ * Unix epoch (Jan 1, 1970).
+ *
+ * They can be converted between POSIX time_t values with SDL_NS_TO_SECONDS()
+ * and SDL_SECONDS_TO_NS(), and between Windows FILETIME values with
+ * SDL_TimeToWindows() and SDL_TimeFromWindows().
+ *
+ * \since This macro is available since SDL 3.2.0.
+ *
+ * \sa SDL_MAX_SINT64
+ * \sa SDL_MIN_SINT64
+ */
+typedef Sint64 SDL_Time;
+#define SDL_MAX_TIME SDL_MAX_SINT64
+#define SDL_MIN_TIME SDL_MIN_SINT64
+/* @} *//* Basic data types */
+/**
+ *  \name Floating-point constants
+ */
+/* @{ */
+#ifdef FLT_EPSILON
+#define SDL_FLT_EPSILON FLT_EPSILON
+#else
+/**
+ * Epsilon constant, used for comparing floating-point numbers.
+ *
+ * Equals by default to platform-defined `FLT_EPSILON`, or
+ * `1.1920928955078125e-07F` if that's not available.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_FLT_EPSILON 1.1920928955078125e-07F /* 0x0.000002p0 */
+#endif
+/* @} *//* Floating-point constants */
+#ifdef SDL_WIKI_DOCUMENTATION_SECTION
+/**
+ * A printf-formatting string for an Sint64 value.
+ *
+ * Use it like this:
+ *
+ * ```c
+ * SDL_Log("There are %" SDL_PRIs64 " bottles of beer on the wall.", bottles);
+ * ```
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_PRIs64 "lld"
+/**
+ * A printf-formatting string for a Uint64 value.
+ *
+ * Use it like this:
+ *
+ * ```c
+ * SDL_Log("There are %" SDL_PRIu64 " bottles of beer on the wall.", bottles);
+ * ```
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_PRIu64 "llu"
+/**
+ * A printf-formatting string for a Uint64 value as lower-case hexadecimal.
+ *
+ * Use it like this:
+ *
+ * ```c
+ * SDL_Log("There are %" SDL_PRIx64 " bottles of beer on the wall.", bottles);
+ * ```
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_PRIx64 "llx"
+/**
+ * A printf-formatting string for a Uint64 value as upper-case hexadecimal.
+ *
+ * Use it like this:
+ *
+ * ```c
+ * SDL_Log("There are %" SDL_PRIX64 " bottles of beer on the wall.", bottles);
+ * ```
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_PRIX64 "llX"
+/**
+ * A printf-formatting string for an Sint32 value.
+ *
+ * Use it like this:
+ *
+ * ```c
+ * SDL_Log("There are %" SDL_PRIs32 " bottles of beer on the wall.", bottles);
+ * ```
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_PRIs32 "d"
+/**
+ * A printf-formatting string for a Uint32 value.
+ *
+ * Use it like this:
+ *
+ * ```c
+ * SDL_Log("There are %" SDL_PRIu32 " bottles of beer on the wall.", bottles);
+ * ```
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_PRIu32 "u"
+/**
+ * A printf-formatting string for a Uint32 value as lower-case hexadecimal.
+ *
+ * Use it like this:
+ *
+ * ```c
+ * SDL_Log("There are %" SDL_PRIx32 " bottles of beer on the wall.", bottles);
+ * ```
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_PRIx32 "x"
+/**
+ * A printf-formatting string for a Uint32 value as upper-case hexadecimal.
+ *
+ * Use it like this:
+ *
+ * ```c
+ * SDL_Log("There are %" SDL_PRIX32 " bottles of beer on the wall.", bottles);
+ * ```
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_PRIX32 "X"
+/**
+ * A printf-formatting string prefix for a `long long` value.
+ *
+ * This is just the prefix! You probably actually want SDL_PRILLd, SDL_PRILLu,
+ * SDL_PRILLx, or SDL_PRILLX instead.
+ *
+ * Use it like this:
+ *
+ * ```c
+ * SDL_Log("There are %" SDL_PRILL_PREFIX "d bottles of beer on the wall.", bottles);
+ * ```
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_PRILL_PREFIX "ll"
+/**
+ * A printf-formatting string for a `long long` value.
+ *
+ * Use it like this:
+ *
+ * ```c
+ * SDL_Log("There are %" SDL_PRILLd " bottles of beer on the wall.", bottles);
+ * ```
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_PRILLd SDL_PRILL_PREFIX "d"
+/**
+ * A printf-formatting string for a `unsigned long long` value.
+ *
+ * Use it like this:
+ *
+ * ```c
+ * SDL_Log("There are %" SDL_PRILLu " bottles of beer on the wall.", bottles);
+ * ```
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_PRILLu SDL_PRILL_PREFIX "u"
+/**
+ * A printf-formatting string for an `unsigned long long` value as lower-case
+ * hexadecimal.
+ *
+ * Use it like this:
+ *
+ * ```c
+ * SDL_Log("There are %" SDL_PRILLx " bottles of beer on the wall.", bottles);
+ * ```
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_PRILLx SDL_PRILL_PREFIX "x"
+/**
+ * A printf-formatting string for an `unsigned long long` value as upper-case
+ * hexadecimal.
+ *
+ * Use it like this:
+ *
+ * ```c
+ * SDL_Log("There are %" SDL_PRILLX " bottles of beer on the wall.", bottles);
+ * ```
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_PRILLX SDL_PRILL_PREFIX "X"
+#endif /* SDL_WIKI_DOCUMENTATION_SECTION */
+/* Make sure we have macros for printing width-based integers.
+ * <inttypes.h> should define these but this is not true all platforms.
+ * (for example win32) */
+#ifndef SDL_PRIs64
+#if defined(SDL_PLATFORM_WINDOWS)
+#define SDL_PRIs64 "I64d"
+#elif defined(PRId64)
+#define SDL_PRIs64 PRId64
+#elif defined(__LP64__) && !defined(SDL_PLATFORM_APPLE) && !defined(__EMSCRIPTEN__)
+#define SDL_PRIs64 "ld"
+#else
+#define SDL_PRIs64 "lld"
+#endif
+#endif
+#ifndef SDL_PRIu64
+#if defined(SDL_PLATFORM_WINDOWS)
+#define SDL_PRIu64 "I64u"
+#elif defined(PRIu64)
+#define SDL_PRIu64 PRIu64
+#elif defined(__LP64__) && !defined(SDL_PLATFORM_APPLE) && !defined(__EMSCRIPTEN__)
+#define SDL_PRIu64 "lu"
+#else
+#define SDL_PRIu64 "llu"
+#endif
+#endif
+#ifndef SDL_PRIx64
+#if defined(SDL_PLATFORM_WINDOWS)
+#define SDL_PRIx64 "I64x"
+#elif defined(PRIx64)
+#define SDL_PRIx64 PRIx64
+#elif defined(__LP64__) && !defined(SDL_PLATFORM_APPLE)
+#define SDL_PRIx64 "lx"
+#else
+#define SDL_PRIx64 "llx"
+#endif
+#endif
+#ifndef SDL_PRIX64
+#if defined(SDL_PLATFORM_WINDOWS)
+#define SDL_PRIX64 "I64X"
+#elif defined(PRIX64)
+#define SDL_PRIX64 PRIX64
+#elif defined(__LP64__) && !defined(SDL_PLATFORM_APPLE)
+#define SDL_PRIX64 "lX"
+#else
+#define SDL_PRIX64 "llX"
+#endif
+#endif
+#ifndef SDL_PRIs32
+#ifdef PRId32
+#define SDL_PRIs32 PRId32
+#else
+#define SDL_PRIs32 "d"
+#endif
+#endif
+#ifndef SDL_PRIu32
+#ifdef PRIu32
+#define SDL_PRIu32 PRIu32
+#else
+#define SDL_PRIu32 "u"
+#endif
+#endif
+#ifndef SDL_PRIx32
+#ifdef PRIx32
+#define SDL_PRIx32 PRIx32
+#else
+#define SDL_PRIx32 "x"
+#endif
+#endif
+#ifndef SDL_PRIX32
+#ifdef PRIX32
+#define SDL_PRIX32 PRIX32
+#else
+#define SDL_PRIX32 "X"
+#endif
+#endif
+/* Specifically for the `long long` -- SDL-specific. */
+#ifdef SDL_PLATFORM_WINDOWS
+#ifndef SDL_NOLONGLONG
+SDL_COMPILE_TIME_ASSERT(longlong_size64, sizeof(long long) == 8); /* using I64 for windows - make sure `long long` is 64 bits. */
+#endif
+#define SDL_PRILL_PREFIX "I64"
+#else
+#define SDL_PRILL_PREFIX "ll"
+#endif
+#ifndef SDL_PRILLd
+#define SDL_PRILLd SDL_PRILL_PREFIX "d"
+#endif
+#ifndef SDL_PRILLu
+#define SDL_PRILLu SDL_PRILL_PREFIX "u"
+#endif
+#ifndef SDL_PRILLx
+#define SDL_PRILLx SDL_PRILL_PREFIX "x"
+#endif
+#ifndef SDL_PRILLX
+#define SDL_PRILLX SDL_PRILL_PREFIX "X"
+#endif
+/* Annotations to help code analysis tools */
+#ifdef SDL_WIKI_DOCUMENTATION_SECTION
+/**
+ * Macro that annotates function params with input buffer size.
+ *
+ * If we were to annotate `memcpy`:
+ *
+ * ```c
+ * void *memcpy(void *dst, SDL_IN_BYTECAP(len) const void *src, size_t len);
+ * ```
+ *
+ * This notes that `src` should be `len` bytes in size and is only read by the
+ * function. The compiler or other analysis tools can warn when this doesn't
+ * appear to be the case.
+ *
+ * On compilers without this annotation mechanism, this is defined to nothing.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_IN_BYTECAP(x) _In_bytecount_(x)
+/**
+ * Macro that annotates function params with input/output string buffer size.
+ *
+ * If we were to annotate `strlcat`:
+ *
+ * ```c
+ * size_t strlcat(SDL_INOUT_Z_CAP(maxlen) char *dst, const char *src, size_t maxlen);
+ * ```
+ *
+ * This notes that `dst` is a null-terminated C string, should be `maxlen`
+ * bytes in size, and is both read from and written to by the function. The
+ * compiler or other analysis tools can warn when this doesn't appear to be
+ * the case.
+ *
+ * On compilers without this annotation mechanism, this is defined to nothing.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_INOUT_Z_CAP(x) _Inout_z_cap_(x)
+/**
+ * Macro that annotates function params with output string buffer size.
+ *
+ * If we were to annotate `snprintf`:
+ *
+ * ```c
+ * int snprintf(SDL_OUT_Z_CAP(maxlen) char *text, size_t maxlen, const char *fmt, ...);
+ * ```
+ *
+ * This notes that `text` is a null-terminated C string, should be `maxlen`
+ * bytes in size, and is only written to by the function. The compiler or
+ * other analysis tools can warn when this doesn't appear to be the case.
+ *
+ * On compilers without this annotation mechanism, this is defined to nothing.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_OUT_Z_CAP(x) _Out_z_cap_(x)
+/**
+ * Macro that annotates function params with output buffer size.
+ *
+ * If we were to annotate `wcsncpy`:
+ *
+ * ```c
+ * char *wcscpy(SDL_OUT_CAP(bufsize) wchar_t *dst, const wchar_t *src, size_t bufsize);
+ * ```
+ *
+ * This notes that `dst` should have a capacity of `bufsize` wchar_t in size,
+ * and is only written to by the function. The compiler or other analysis
+ * tools can warn when this doesn't appear to be the case.
+ *
+ * This operates on counts of objects, not bytes. Use SDL_OUT_BYTECAP for
+ * bytes.
+ *
+ * On compilers without this annotation mechanism, this is defined to nothing.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_OUT_CAP(x) _Out_cap_(x)
+/**
+ * Macro that annotates function params with output buffer size.
+ *
+ * If we were to annotate `memcpy`:
+ *
+ * ```c
+ * void *memcpy(SDL_OUT_BYTECAP(bufsize) void *dst, const void *src, size_t bufsize);
+ * ```
+ *
+ * This notes that `dst` should have a capacity of `bufsize` bytes in size,
+ * and is only written to by the function. The compiler or other analysis
+ * tools can warn when this doesn't appear to be the case.
+ *
+ * On compilers without this annotation mechanism, this is defined to nothing.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_OUT_BYTECAP(x) _Out_bytecap_(x)
+/**
+ * Macro that annotates function params with output buffer string size.
+ *
+ * If we were to annotate `strcpy`:
+ *
+ * ```c
+ * char *strcpy(SDL_OUT_Z_BYTECAP(bufsize) char *dst, const char *src, size_t bufsize);
+ * ```
+ *
+ * This notes that `dst` should have a capacity of `bufsize` bytes in size,
+ * and a zero-terminated string is written to it by the function. The compiler
+ * or other analysis tools can warn when this doesn't appear to be the case.
+ *
+ * On compilers without this annotation mechanism, this is defined to nothing.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_OUT_Z_BYTECAP(x) _Out_z_bytecap_(x)
+/**
+ * Macro that annotates function params as printf-style format strings.
+ *
+ * If we were to annotate `fprintf`:
+ *
+ * ```c
+ * int fprintf(FILE *f, SDL_PRINTF_FORMAT_STRING const char *fmt, ...);
+ * ```
+ *
+ * This notes that `fmt` should be a printf-style format string. The compiler
+ * or other analysis tools can warn when this doesn't appear to be the case.
+ *
+ * On compilers without this annotation mechanism, this is defined to nothing.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_PRINTF_FORMAT_STRING _Printf_format_string_
+/**
+ * Macro that annotates function params as scanf-style format strings.
+ *
+ * If we were to annotate `fscanf`:
+ *
+ * ```c
+ * int fscanf(FILE *f, SDL_SCANF_FORMAT_STRING const char *fmt, ...);
+ * ```
+ *
+ * This notes that `fmt` should be a scanf-style format string. The compiler
+ * or other analysis tools can warn when this doesn't appear to be the case.
+ *
+ * On compilers without this annotation mechanism, this is defined to nothing.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_SCANF_FORMAT_STRING _Scanf_format_string_impl_
+/**
+ * Macro that annotates a vararg function that operates like printf.
+ *
+ * If we were to annotate `fprintf`:
+ *
+ * ```c
+ * int fprintf(FILE *f, const char *fmt, ...) SDL_PRINTF_VARARG_FUNC(2);
+ * ```
+ *
+ * This notes that the second parameter should be a printf-style format
+ * string, followed by `...`. The compiler or other analysis tools can warn
+ * when this doesn't appear to be the case.
+ *
+ * On compilers without this annotation mechanism, this is defined to nothing.
+ *
+ * This can (and should) be used with SDL_PRINTF_FORMAT_STRING as well, which
+ * between them will cover at least Visual Studio, GCC, and Clang.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_PRINTF_VARARG_FUNC( fmtargnumber ) __attribute__ (( format( __printf__, fmtargnumber, fmtargnumber+1 )))
+/**
+ * Macro that annotates a va_list function that operates like printf.
+ *
+ * If we were to annotate `vfprintf`:
+ *
+ * ```c
+ * int vfprintf(FILE *f, const char *fmt, va_list ap) SDL_PRINTF_VARARG_FUNCV(2);
+ * ```
+ *
+ * This notes that the second parameter should be a printf-style format
+ * string, followed by a va_list. The compiler or other analysis tools can
+ * warn when this doesn't appear to be the case.
+ *
+ * On compilers without this annotation mechanism, this is defined to nothing.
+ *
+ * This can (and should) be used with SDL_PRINTF_FORMAT_STRING as well, which
+ * between them will cover at least Visual Studio, GCC, and Clang.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_PRINTF_VARARG_FUNCV( fmtargnumber ) __attribute__(( format( __printf__, fmtargnumber, 0 )))
+/**
+ * Macro that annotates a vararg function that operates like scanf.
+ *
+ * If we were to annotate `fscanf`:
+ *
+ * ```c
+ * int fscanf(FILE *f, const char *fmt, ...) SDL_PRINTF_VARARG_FUNCV(2);
+ * ```
+ *
+ * This notes that the second parameter should be a scanf-style format string,
+ * followed by `...`. The compiler or other analysis tools can warn when this
+ * doesn't appear to be the case.
+ *
+ * On compilers without this annotation mechanism, this is defined to nothing.
+ *
+ * This can (and should) be used with SDL_SCANF_FORMAT_STRING as well, which
+ * between them will cover at least Visual Studio, GCC, and Clang.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_SCANF_VARARG_FUNC( fmtargnumber ) __attribute__ (( format( __scanf__, fmtargnumber, fmtargnumber+1 )))
+/**
+ * Macro that annotates a va_list function that operates like scanf.
+ *
+ * If we were to annotate `vfscanf`:
+ *
+ * ```c
+ * int vfscanf(FILE *f, const char *fmt, va_list ap) SDL_PRINTF_VARARG_FUNCV(2);
+ * ```
+ *
+ * This notes that the second parameter should be a scanf-style format string,
+ * followed by a va_list. The compiler or other analysis tools can warn when
+ * this doesn't appear to be the case.
+ *
+ * On compilers without this annotation mechanism, this is defined to nothing.
+ *
+ * This can (and should) be used with SDL_SCANF_FORMAT_STRING as well, which
+ * between them will cover at least Visual Studio, GCC, and Clang.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_SCANF_VARARG_FUNCV( fmtargnumber ) __attribute__(( format( __scanf__, fmtargnumber, 0 )))
+/**
+ * Macro that annotates a vararg function that operates like wprintf.
+ *
+ * If we were to annotate `fwprintf`:
+ *
+ * ```c
+ * int fwprintf(FILE *f, const wchar_t *fmt, ...) SDL_WPRINTF_VARARG_FUNC(2);
+ * ```
+ *
+ * This notes that the second parameter should be a wprintf-style format wide
+ * string, followed by `...`. The compiler or other analysis tools can warn
+ * when this doesn't appear to be the case.
+ *
+ * On compilers without this annotation mechanism, this is defined to nothing.
+ *
+ * This can (and should) be used with SDL_PRINTF_FORMAT_STRING as well, which
+ * between them will cover at least Visual Studio, GCC, and Clang.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_WPRINTF_VARARG_FUNC( fmtargnumber ) /* __attribute__ (( format( __wprintf__, fmtargnumber, fmtargnumber+1 ))) */
+/**
+ * Macro that annotates a va_list function that operates like wprintf.
+ *
+ * If we were to annotate `vfwprintf`:
+ *
+ * ```c
+ * int vfwprintf(FILE *f, const wchar_t *fmt, va_list ap) SDL_WPRINTF_VARARG_FUNC(2);
+ * ```
+ *
+ * This notes that the second parameter should be a wprintf-style format wide
+ * string, followed by a va_list. The compiler or other analysis tools can
+ * warn when this doesn't appear to be the case.
+ *
+ * On compilers without this annotation mechanism, this is defined to nothing.
+ *
+ * This can (and should) be used with SDL_PRINTF_FORMAT_STRING as well, which
+ * between them will cover at least Visual Studio, GCC, and Clang.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_WPRINTF_VARARG_FUNCV( fmtargnumber ) /* __attribute__ (( format( __wprintf__, fmtargnumber, 0 ))) */
+#elif defined(SDL_DISABLE_ANALYZE_MACROS)
+#define SDL_IN_BYTECAP(x)
+#define SDL_INOUT_Z_CAP(x)
+#define SDL_OUT_Z_CAP(x)
+#define SDL_OUT_CAP(x)
+#define SDL_OUT_BYTECAP(x)
+#define SDL_OUT_Z_BYTECAP(x)
+#define SDL_PRINTF_FORMAT_STRING
+#define SDL_SCANF_FORMAT_STRING
+#define SDL_PRINTF_VARARG_FUNC( fmtargnumber )
+#define SDL_PRINTF_VARARG_FUNCV( fmtargnumber )
+#define SDL_SCANF_VARARG_FUNC( fmtargnumber )
+#define SDL_SCANF_VARARG_FUNCV( fmtargnumber )
+#define SDL_WPRINTF_VARARG_FUNC( fmtargnumber )
+#define SDL_WPRINTF_VARARG_FUNCV( fmtargnumber )
+#else
+#if defined(_MSC_VER) && (_MSC_VER >= 1600) /* VS 2010 and above */
+#include <sal.h>
+#define SDL_IN_BYTECAP(x) _In_bytecount_(x)
+#define SDL_INOUT_Z_CAP(x) _Inout_z_cap_(x)
+#define SDL_OUT_Z_CAP(x) _Out_z_cap_(x)
+#define SDL_OUT_CAP(x) _Out_cap_(x)
+#define SDL_OUT_BYTECAP(x) _Out_bytecap_(x)
+#define SDL_OUT_Z_BYTECAP(x) _Out_z_bytecap_(x)
+#define SDL_PRINTF_FORMAT_STRING _Printf_format_string_
+#define SDL_SCANF_FORMAT_STRING _Scanf_format_string_impl_
+#else
+#define SDL_IN_BYTECAP(x)
+#define SDL_INOUT_Z_CAP(x)
+#define SDL_OUT_Z_CAP(x)
+#define SDL_OUT_CAP(x)
+#define SDL_OUT_BYTECAP(x)
+#define SDL_OUT_Z_BYTECAP(x)
+#define SDL_PRINTF_FORMAT_STRING
+#define SDL_SCANF_FORMAT_STRING
+#endif
+#if defined(__GNUC__) || defined(__clang__)
+#define SDL_PRINTF_VARARG_FUNC( fmtargnumber ) __attribute__ (( format( __printf__, fmtargnumber, fmtargnumber+1 )))
+#define SDL_PRINTF_VARARG_FUNCV( fmtargnumber ) __attribute__(( format( __printf__, fmtargnumber, 0 )))
+#define SDL_SCANF_VARARG_FUNC( fmtargnumber ) __attribute__ (( format( __scanf__, fmtargnumber, fmtargnumber+1 )))
+#define SDL_SCANF_VARARG_FUNCV( fmtargnumber ) __attribute__(( format( __scanf__, fmtargnumber, 0 )))
+#define SDL_WPRINTF_VARARG_FUNC( fmtargnumber ) /* __attribute__ (( format( __wprintf__, fmtargnumber, fmtargnumber+1 ))) */
+#define SDL_WPRINTF_VARARG_FUNCV( fmtargnumber ) /* __attribute__ (( format( __wprintf__, fmtargnumber, 0 ))) */
+#else
+#define SDL_PRINTF_VARARG_FUNC( fmtargnumber )
+#define SDL_PRINTF_VARARG_FUNCV( fmtargnumber )
+#define SDL_SCANF_VARARG_FUNC( fmtargnumber )
+#define SDL_SCANF_VARARG_FUNCV( fmtargnumber )
+#define SDL_WPRINTF_VARARG_FUNC( fmtargnumber )
+#define SDL_WPRINTF_VARARG_FUNCV( fmtargnumber )
+#endif
+#endif /* SDL_DISABLE_ANALYZE_MACROS */
+/** \cond */
+#ifndef DOXYGEN_SHOULD_IGNORE_THIS
+SDL_COMPILE_TIME_ASSERT(bool_size, sizeof(bool) == 1);
+SDL_COMPILE_TIME_ASSERT(uint8_size, sizeof(Uint8) == 1);
+SDL_COMPILE_TIME_ASSERT(sint8_size, sizeof(Sint8) == 1);
+SDL_COMPILE_TIME_ASSERT(uint16_size, sizeof(Uint16) == 2);
+SDL_COMPILE_TIME_ASSERT(sint16_size, sizeof(Sint16) == 2);
+SDL_COMPILE_TIME_ASSERT(uint32_size, sizeof(Uint32) == 4);
+SDL_COMPILE_TIME_ASSERT(sint32_size, sizeof(Sint32) == 4);
+SDL_COMPILE_TIME_ASSERT(uint64_size, sizeof(Uint64) == 8);
+SDL_COMPILE_TIME_ASSERT(sint64_size, sizeof(Sint64) == 8);
+#ifndef SDL_NOLONGLONG
+SDL_COMPILE_TIME_ASSERT(uint64_longlong, sizeof(Uint64) <= sizeof(unsigned long long));
+SDL_COMPILE_TIME_ASSERT(size_t_longlong, sizeof(size_t) <= sizeof(unsigned long long));
+#endif
+typedef struct SDL_alignment_test
+{
+    Uint8 a;
+    void *b;
+} SDL_alignment_test;
+SDL_COMPILE_TIME_ASSERT(struct_alignment, sizeof(SDL_alignment_test) == (2 * sizeof(void *)));
+SDL_COMPILE_TIME_ASSERT(two_s_complement, (int)~(int)0 == (int)(-1));
+#endif /* DOXYGEN_SHOULD_IGNORE_THIS */
+/** \endcond */
+/* Check to make sure enums are the size of ints, for structure packing.
+   For both Watcom C/C++ and Borland C/C++ the compiler option that makes
+   enums having the size of an int must be enabled.
+   This is "-b" for Borland C/C++ and "-ei" for Watcom C/C++ (v11).
+*/
+/** \cond */
+#ifndef DOXYGEN_SHOULD_IGNORE_THIS
+#if !defined(SDL_PLATFORM_VITA) && !defined(SDL_PLATFORM_3DS)
+/* TODO: include/SDL_stdinc.h:390: error: size of array 'SDL_dummy_enum' is negative */
+typedef enum SDL_DUMMY_ENUM
+{
+    DUMMY_ENUM_VALUE
+} SDL_DUMMY_ENUM;
+SDL_COMPILE_TIME_ASSERT(enum, sizeof(SDL_DUMMY_ENUM) == sizeof(int));
+#endif
+#endif /* DOXYGEN_SHOULD_IGNORE_THIS */
+/** \endcond */
+#include <SDL3/SDL_begin_code.h>
+/* Set up for C function definitions, even when using C++ */
+#ifdef __cplusplus
+extern "C" {
+#endif
+/**
+ * A macro to initialize an SDL interface.
+ *
+ * This macro will initialize an SDL interface structure and should be called
+ * before you fill out the fields with your implementation.
+ *
+ * You can use it like this:
+ *
+ * ```c
+ * SDL_IOStreamInterface iface;
+ *
+ * SDL_INIT_INTERFACE(&iface);
+ *
+ * // Fill in the interface function pointers with your implementation
+ * iface.seek = ...
+ *
+ * stream = SDL_OpenIO(&iface, NULL);
+ * ```
+ *
+ * If you are using designated initializers, you can use the size of the
+ * interface as the version, e.g.
+ *
+ * ```c
+ * SDL_IOStreamInterface iface = {
+ *     .version = sizeof(iface),
+ *     .seek = ...
+ * };
+ * stream = SDL_OpenIO(&iface, NULL);
+ * ```
+ *
+ * \threadsafety It is safe to call this macro from any thread.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ *
+ * \sa SDL_IOStreamInterface
+ * \sa SDL_StorageInterface
+ * \sa SDL_VirtualJoystickDesc
+ */
+#define SDL_INIT_INTERFACE(iface)               \
+    do {                                        \
+        SDL_zerop(iface);                       \
+        (iface)->version = sizeof(*(iface));    \
+    } while (0)
+#ifdef SDL_WIKI_DOCUMENTATION_SECTION
+/**
+ * Allocate memory on the stack (maybe).
+ *
+ * If SDL knows how to access alloca() on the current platform, it will use it
+ * to stack-allocate memory here. If it doesn't, it will use SDL_malloc() to
+ * heap-allocate memory.
+ *
+ * Since this might not be stack memory at all, it's important that you check
+ * the returned pointer for NULL, and that you call SDL_stack_free on the
+ * memory when done with it. Since this might be stack memory, it's important
+ * that you don't allocate large amounts of it, or allocate in a loop without
+ * returning from the function, so the stack doesn't overflow.
+ *
+ * \param type the datatype of the memory to allocate.
+ * \param count the number of `type` objects to allocate.
+ * \returns newly-allocated memory, or NULL on failure.
+ *
+ * \threadsafety It is safe to call this macro from any thread.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ *
+ * \sa SDL_stack_free
+ */
+#define SDL_stack_alloc(type, count)    (type*)alloca(sizeof(type)*(count))
+/**
+ * Free memory previously allocated with SDL_stack_alloc.
+ *
+ * If SDL used alloca() to allocate this memory, this macro does nothing and
+ * the allocated memory will be automatically released when the function that
+ * called SDL_stack_alloc() returns. If SDL used SDL_malloc(), it will
+ * SDL_free the memory immediately.
+ *
+ * \param data the pointer, from SDL_stack_alloc(), to free.
+ *
+ * \threadsafety It is safe to call this macro from any thread.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ *
+ * \sa SDL_stack_alloc
+ */
+#define SDL_stack_free(data)
+#elif !defined(SDL_DISABLE_ALLOCA)
+#define SDL_stack_alloc(type, count)    (type*)alloca(sizeof(type)*(count))
+#define SDL_stack_free(data)
+#else
+#define SDL_stack_alloc(type, count)    (type*)SDL_malloc(sizeof(type)*(count))
+#define SDL_stack_free(data)            SDL_free(data)
+#endif
+/**
+ * Allocate uninitialized memory.
+ *
+ * The allocated memory returned by this function must be freed with
+ * SDL_free().
+ *
+ * If `size` is 0, it will be set to 1.
+ *
+ * If you want to allocate memory aligned to a specific alignment, consider
+ * using SDL_aligned_alloc().
+ *
+ * \param size the size to allocate.
+ * \returns a pointer to the allocated memory, or NULL if allocation failed.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_free
+ * \sa SDL_calloc
+ * \sa SDL_realloc
+ * \sa SDL_aligned_alloc
+ */
+extern SDL_DECLSPEC SDL_MALLOC void * SDLCALL SDL_malloc(size_t size);
+/**
+ * Allocate a zero-initialized array.
+ *
+ * The memory returned by this function must be freed with SDL_free().
+ *
+ * If either of `nmemb` or `size` is 0, they will both be set to 1.
+ *
+ * \param nmemb the number of elements in the array.
+ * \param size the size of each element of the array.
+ * \returns a pointer to the allocated array, or NULL if allocation failed.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_free
+ * \sa SDL_malloc
+ * \sa SDL_realloc
+ */
+extern SDL_DECLSPEC SDL_MALLOC SDL_ALLOC_SIZE2(1, 2) void * SDLCALL SDL_calloc(size_t nmemb, size_t size);
+/**
+ * Change the size of allocated memory.
+ *
+ * The memory returned by this function must be freed with SDL_free().
+ *
+ * If `size` is 0, it will be set to 1. Note that this is unlike some other C
+ * runtime `realloc` implementations, which may treat `realloc(mem, 0)` the
+ * same way as `free(mem)`.
+ *
+ * If `mem` is NULL, the behavior of this function is equivalent to
+ * SDL_malloc(). Otherwise, the function can have one of three possible
+ * outcomes:
+ *
+ * - If it returns the same pointer as `mem`, it means that `mem` was resized
+ *   in place without freeing.
+ * - If it returns a different non-NULL pointer, it means that `mem` was freed
+ *   and cannot be dereferenced anymore.
+ * - If it returns NULL (indicating failure), then `mem` will remain valid and
+ *   must still be freed with SDL_free().
+ *
+ * \param mem a pointer to allocated memory to reallocate, or NULL.
+ * \param size the new size of the memory.
+ * \returns a pointer to the newly allocated memory, or NULL if allocation
+ *          failed.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_free
+ * \sa SDL_malloc
+ * \sa SDL_calloc
+ */
+extern SDL_DECLSPEC SDL_ALLOC_SIZE(2) void * SDLCALL SDL_realloc(void *mem, size_t size);
+/**
+ * Free allocated memory.
+ *
+ * The pointer is no longer valid after this call and cannot be dereferenced
+ * anymore.
+ *
+ * If `mem` is NULL, this function does nothing.
+ *
+ * \param mem a pointer to allocated memory, or NULL.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_malloc
+ * \sa SDL_calloc
+ * \sa SDL_realloc
+ */
+extern SDL_DECLSPEC void SDLCALL SDL_free(void *mem);
+/**
+ * A callback used to implement SDL_malloc().
+ *
+ * SDL will always ensure that the passed `size` is greater than 0.
+ *
+ * \param size the size to allocate.
+ * \returns a pointer to the allocated memory, or NULL if allocation failed.
+ *
+ * \threadsafety It should be safe to call this callback from any thread.
+ *
+ * \since This datatype is available since SDL 3.2.0.
+ *
+ * \sa SDL_malloc
+ * \sa SDL_GetOriginalMemoryFunctions
+ * \sa SDL_GetMemoryFunctions
+ * \sa SDL_SetMemoryFunctions
+ */
+typedef void *(SDLCALL *SDL_malloc_func)(size_t size);
+/**
+ * A callback used to implement SDL_calloc().
+ *
+ * SDL will always ensure that the passed `nmemb` and `size` are both greater
+ * than 0.
+ *
+ * \param nmemb the number of elements in the array.
+ * \param size the size of each element of the array.
+ * \returns a pointer to the allocated array, or NULL if allocation failed.
+ *
+ * \threadsafety It should be safe to call this callback from any thread.
+ *
+ * \since This datatype is available since SDL 3.2.0.
+ *
+ * \sa SDL_calloc
+ * \sa SDL_GetOriginalMemoryFunctions
+ * \sa SDL_GetMemoryFunctions
+ * \sa SDL_SetMemoryFunctions
+ */
+typedef void *(SDLCALL *SDL_calloc_func)(size_t nmemb, size_t size);
+/**
+ * A callback used to implement SDL_realloc().
+ *
+ * SDL will always ensure that the passed `size` is greater than 0.
+ *
+ * \param mem a pointer to allocated memory to reallocate, or NULL.
+ * \param size the new size of the memory.
+ * \returns a pointer to the newly allocated memory, or NULL if allocation
+ *          failed.
+ *
+ * \threadsafety It should be safe to call this callback from any thread.
+ *
+ * \since This datatype is available since SDL 3.2.0.
+ *
+ * \sa SDL_realloc
+ * \sa SDL_GetOriginalMemoryFunctions
+ * \sa SDL_GetMemoryFunctions
+ * \sa SDL_SetMemoryFunctions
+ */
+typedef void *(SDLCALL *SDL_realloc_func)(void *mem, size_t size);
+/**
+ * A callback used to implement SDL_free().
+ *
+ * SDL will always ensure that the passed `mem` is a non-NULL pointer.
+ *
+ * \param mem a pointer to allocated memory.
+ *
+ * \threadsafety It should be safe to call this callback from any thread.
+ *
+ * \since This datatype is available since SDL 3.2.0.
+ *
+ * \sa SDL_free
+ * \sa SDL_GetOriginalMemoryFunctions
+ * \sa SDL_GetMemoryFunctions
+ * \sa SDL_SetMemoryFunctions
+ */
+typedef void (SDLCALL *SDL_free_func)(void *mem);
+/**
+ * Get the original set of SDL memory functions.
+ *
+ * This is what SDL_malloc and friends will use by default, if there has been
+ * no call to SDL_SetMemoryFunctions. This is not necessarily using the C
+ * runtime's `malloc` functions behind the scenes! Different platforms and
+ * build configurations might do any number of unexpected things.
+ *
+ * \param malloc_func filled with malloc function.
+ * \param calloc_func filled with calloc function.
+ * \param realloc_func filled with realloc function.
+ * \param free_func filled with free function.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC void SDLCALL SDL_GetOriginalMemoryFunctions(SDL_malloc_func *malloc_func,
+                                                            SDL_calloc_func *calloc_func,
+                                                            SDL_realloc_func *realloc_func,
+                                                            SDL_free_func *free_func);
+/**
+ * Get the current set of SDL memory functions.
+ *
+ * \param malloc_func filled with malloc function.
+ * \param calloc_func filled with calloc function.
+ * \param realloc_func filled with realloc function.
+ * \param free_func filled with free function.
+ *
+ * \threadsafety This does not hold a lock, so do not call this in the
+ *               unlikely event of a background thread calling
+ *               SDL_SetMemoryFunctions simultaneously.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_SetMemoryFunctions
+ * \sa SDL_GetOriginalMemoryFunctions
+ */
+extern SDL_DECLSPEC void SDLCALL SDL_GetMemoryFunctions(SDL_malloc_func *malloc_func,
+                                                    SDL_calloc_func *calloc_func,
+                                                    SDL_realloc_func *realloc_func,
+                                                    SDL_free_func *free_func);
+/**
+ * Replace SDL's memory allocation functions with a custom set.
+ *
+ * It is not safe to call this function once any allocations have been made,
+ * as future calls to SDL_free will use the new allocator, even if they came
+ * from an SDL_malloc made with the old one!
+ *
+ * If used, usually this needs to be the first call made into the SDL library,
+ * if not the very first thing done at program startup time.
+ *
+ * \param malloc_func custom malloc function.
+ * \param calloc_func custom calloc function.
+ * \param realloc_func custom realloc function.
+ * \param free_func custom free function.
+ * \returns true on success or false on failure; call SDL_GetError() for more
+ *          information.
+ *
+ * \threadsafety It is safe to call this function from any thread, but one
+ *               should not replace the memory functions once any allocations
+ *               are made!
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_GetMemoryFunctions
+ * \sa SDL_GetOriginalMemoryFunctions
+ */
+extern SDL_DECLSPEC bool SDLCALL SDL_SetMemoryFunctions(SDL_malloc_func malloc_func,
+                                                            SDL_calloc_func calloc_func,
+                                                            SDL_realloc_func realloc_func,
+                                                            SDL_free_func free_func);
+/**
+ * Allocate memory aligned to a specific alignment.
+ *
+ * The memory returned by this function must be freed with SDL_aligned_free(),
+ * _not_ SDL_free().
+ *
+ * If `alignment` is less than the size of `void *`, it will be increased to
+ * match that.
+ *
+ * The returned memory address will be a multiple of the alignment value, and
+ * the size of the memory allocated will be a multiple of the alignment value.
+ *
+ * \param alignment the alignment of the memory.
+ * \param size the size to allocate.
+ * \returns a pointer to the aligned memory, or NULL if allocation failed.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_aligned_free
+ */
+extern SDL_DECLSPEC SDL_MALLOC void * SDLCALL SDL_aligned_alloc(size_t alignment, size_t size);
+/**
+ * Free memory allocated by SDL_aligned_alloc().
+ *
+ * The pointer is no longer valid after this call and cannot be dereferenced
+ * anymore.
+ *
+ * If `mem` is NULL, this function does nothing.
+ *
+ * \param mem a pointer previously returned by SDL_aligned_alloc(), or NULL.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_aligned_alloc
+ */
+extern SDL_DECLSPEC void SDLCALL SDL_aligned_free(void *mem);
+/**
+ * Get the number of outstanding (unfreed) allocations.
+ *
+ * \returns the number of allocations or -1 if allocation counting is
+ *          disabled.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_GetNumAllocations(void);
+/**
+ * A thread-safe set of environment variables
+ *
+ * \since This struct is available since SDL 3.2.0.
+ *
+ * \sa SDL_GetEnvironment
+ * \sa SDL_CreateEnvironment
+ * \sa SDL_GetEnvironmentVariable
+ * \sa SDL_GetEnvironmentVariables
+ * \sa SDL_SetEnvironmentVariable
+ * \sa SDL_UnsetEnvironmentVariable
+ * \sa SDL_DestroyEnvironment
+ */
+typedef struct SDL_Environment SDL_Environment;
+/**
+ * Get the process environment.
+ *
+ * This is initialized at application start and is not affected by setenv()
+ * and unsetenv() calls after that point. Use SDL_SetEnvironmentVariable() and
+ * SDL_UnsetEnvironmentVariable() if you want to modify this environment, or
+ * SDL_setenv_unsafe() or SDL_unsetenv_unsafe() if you want changes to persist
+ * in the C runtime environment after SDL_Quit().
+ *
+ * \returns a pointer to the environment for the process or NULL on failure;
+ *          call SDL_GetError() for more information.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_GetEnvironmentVariable
+ * \sa SDL_GetEnvironmentVariables
+ * \sa SDL_SetEnvironmentVariable
+ * \sa SDL_UnsetEnvironmentVariable
+ */
+extern SDL_DECLSPEC SDL_Environment * SDLCALL SDL_GetEnvironment(void);
+/**
+ * Create a set of environment variables
+ *
+ * \param populated true to initialize it from the C runtime environment,
+ *                  false to create an empty environment.
+ * \returns a pointer to the new environment or NULL on failure; call
+ *          SDL_GetError() for more information.
+ *
+ * \threadsafety If `populated` is false, it is safe to call this function
+ *               from any thread, otherwise it is safe if no other threads are
+ *               calling setenv() or unsetenv()
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_GetEnvironmentVariable
+ * \sa SDL_GetEnvironmentVariables
+ * \sa SDL_SetEnvironmentVariable
+ * \sa SDL_UnsetEnvironmentVariable
+ * \sa SDL_DestroyEnvironment
+ */
+extern SDL_DECLSPEC SDL_Environment * SDLCALL SDL_CreateEnvironment(bool populated);
+/**
+ * Get the value of a variable in the environment.
+ *
+ * \param env the environment to query.
+ * \param name the name of the variable to get.
+ * \returns a pointer to the value of the variable or NULL if it can't be
+ *          found.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_GetEnvironment
+ * \sa SDL_CreateEnvironment
+ * \sa SDL_GetEnvironmentVariables
+ * \sa SDL_SetEnvironmentVariable
+ * \sa SDL_UnsetEnvironmentVariable
+ */
+extern SDL_DECLSPEC const char * SDLCALL SDL_GetEnvironmentVariable(SDL_Environment *env, const char *name);
+/**
+ * Get all variables in the environment.
+ *
+ * \param env the environment to query.
+ * \returns a NULL terminated array of pointers to environment variables in
+ *          the form "variable=value" or NULL on failure; call SDL_GetError()
+ *          for more information. This is a single allocation that should be
+ *          freed with SDL_free() when it is no longer needed.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_GetEnvironment
+ * \sa SDL_CreateEnvironment
+ * \sa SDL_GetEnvironmentVariables
+ * \sa SDL_SetEnvironmentVariable
+ * \sa SDL_UnsetEnvironmentVariable
+ */
+extern SDL_DECLSPEC char ** SDLCALL SDL_GetEnvironmentVariables(SDL_Environment *env);
+/**
+ * Set the value of a variable in the environment.
+ *
+ * \param env the environment to modify.
+ * \param name the name of the variable to set.
+ * \param value the value of the variable to set.
+ * \param overwrite true to overwrite the variable if it exists, false to
+ *                  return success without setting the variable if it already
+ *                  exists.
+ * \returns true on success or false on failure; call SDL_GetError() for more
+ *          information.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_GetEnvironment
+ * \sa SDL_CreateEnvironment
+ * \sa SDL_GetEnvironmentVariable
+ * \sa SDL_GetEnvironmentVariables
+ * \sa SDL_UnsetEnvironmentVariable
+ */
+extern SDL_DECLSPEC bool SDLCALL SDL_SetEnvironmentVariable(SDL_Environment *env, const char *name, const char *value, bool overwrite);
+/**
+ * Clear a variable from the environment.
+ *
+ * \param env the environment to modify.
+ * \param name the name of the variable to unset.
+ * \returns true on success or false on failure; call SDL_GetError() for more
+ *          information.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_GetEnvironment
+ * \sa SDL_CreateEnvironment
+ * \sa SDL_GetEnvironmentVariable
+ * \sa SDL_GetEnvironmentVariables
+ * \sa SDL_SetEnvironmentVariable
+ * \sa SDL_UnsetEnvironmentVariable
+ */
+extern SDL_DECLSPEC bool SDLCALL SDL_UnsetEnvironmentVariable(SDL_Environment *env, const char *name);
+/**
+ * Destroy a set of environment variables.
+ *
+ * \param env the environment to destroy.
+ *
+ * \threadsafety It is safe to call this function from any thread, as long as
+ *               the environment is no longer in use.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_CreateEnvironment
+ */
+extern SDL_DECLSPEC void SDLCALL SDL_DestroyEnvironment(SDL_Environment *env);
+/**
+ * Get the value of a variable in the environment.
+ *
+ * This function uses SDL's cached copy of the environment and is thread-safe.
+ *
+ * \param name the name of the variable to get.
+ * \returns a pointer to the value of the variable or NULL if it can't be
+ *          found.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC const char * SDLCALL SDL_getenv(const char *name);
+/**
+ * Get the value of a variable in the environment.
+ *
+ * This function bypasses SDL's cached copy of the environment and is not
+ * thread-safe.
+ *
+ * \param name the name of the variable to get.
+ * \returns a pointer to the value of the variable or NULL if it can't be
+ *          found.
+ *
+ * \threadsafety This function is not thread safe, consider using SDL_getenv()
+ *               instead.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_getenv
+ */
+extern SDL_DECLSPEC const char * SDLCALL SDL_getenv_unsafe(const char *name);
+/**
+ * Set the value of a variable in the environment.
+ *
+ * \param name the name of the variable to set.
+ * \param value the value of the variable to set.
+ * \param overwrite 1 to overwrite the variable if it exists, 0 to return
+ *                  success without setting the variable if it already exists.
+ * \returns 0 on success, -1 on error.
+ *
+ * \threadsafety This function is not thread safe, consider using
+ *               SDL_SetEnvironmentVariable() instead.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_SetEnvironmentVariable
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_setenv_unsafe(const char *name, const char *value, int overwrite);
+/**
+ * Clear a variable from the environment.
+ *
+ * \param name the name of the variable to unset.
+ * \returns 0 on success, -1 on error.
+ *
+ * \threadsafety This function is not thread safe, consider using
+ *               SDL_UnsetEnvironmentVariable() instead.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_UnsetEnvironmentVariable
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_unsetenv_unsafe(const char *name);
+/**
+ * A callback used with SDL sorting and binary search functions.
+ *
+ * \param a a pointer to the first element being compared.
+ * \param b a pointer to the second element being compared.
+ * \returns -1 if `a` should be sorted before `b`, 1 if `b` should be sorted
+ *          before `a`, 0 if they are equal. If two elements are equal, their
+ *          order in the sorted array is undefined.
+ *
+ * \since This callback is available since SDL 3.2.0.
+ *
+ * \sa SDL_bsearch
+ * \sa SDL_qsort
+ */
+typedef int (SDLCALL *SDL_CompareCallback)(const void *a, const void *b);
+/**
+ * Sort an array.
+ *
+ * For example:
+ *
+ * ```c
+ * typedef struct {
+ *     int key;
+ *     const char *string;
+ * } data;
+ *
+ * int SDLCALL compare(const void *a, const void *b)
+ * {
+ *     const data *A = (const data *)a;
+ *     const data *B = (const data *)b;
+ *
+ *     if (A->n < B->n) {
+ *         return -1;
+ *     } else if (B->n < A->n) {
+ *         return 1;
+ *     } else {
+ *         return 0;
+ *     }
+ * }
+ *
+ * data values[] = {
+ *     { 3, "third" }, { 1, "first" }, { 2, "second" }
+ * };
+ *
+ * SDL_qsort(values, SDL_arraysize(values), sizeof(values[0]), compare);
+ * ```
+ *
+ * \param base a pointer to the start of the array.
+ * \param nmemb the number of elements in the array.
+ * \param size the size of the elements in the array.
+ * \param compare a function used to compare elements in the array.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_bsearch
+ * \sa SDL_qsort_r
+ */
+extern SDL_DECLSPEC void SDLCALL SDL_qsort(void *base, size_t nmemb, size_t size, SDL_CompareCallback compare);
+/**
+ * Perform a binary search on a previously sorted array.
+ *
+ * For example:
+ *
+ * ```c
+ * typedef struct {
+ *     int key;
+ *     const char *string;
+ * } data;
+ *
+ * int SDLCALL compare(const void *a, const void *b)
+ * {
+ *     const data *A = (const data *)a;
+ *     const data *B = (const data *)b;
+ *
+ *     if (A->n < B->n) {
+ *         return -1;
+ *     } else if (B->n < A->n) {
+ *         return 1;
+ *     } else {
+ *         return 0;
+ *     }
+ * }
+ *
+ * data values[] = {
+ *     { 1, "first" }, { 2, "second" }, { 3, "third" }
+ * };
+ * data key = { 2, NULL };
+ *
+ * data *result = SDL_bsearch(&key, values, SDL_arraysize(values), sizeof(values[0]), compare);
+ * ```
+ *
+ * \param key a pointer to a key equal to the element being searched for.
+ * \param base a pointer to the start of the array.
+ * \param nmemb the number of elements in the array.
+ * \param size the size of the elements in the array.
+ * \param compare a function used to compare elements in the array.
+ * \returns a pointer to the matching element in the array, or NULL if not
+ *          found.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_bsearch_r
+ * \sa SDL_qsort
+ */
+extern SDL_DECLSPEC void * SDLCALL SDL_bsearch(const void *key, const void *base, size_t nmemb, size_t size, SDL_CompareCallback compare);
+/**
+ * A callback used with SDL sorting and binary search functions.
+ *
+ * \param userdata the `userdata` pointer passed to the sort function.
+ * \param a a pointer to the first element being compared.
+ * \param b a pointer to the second element being compared.
+ * \returns -1 if `a` should be sorted before `b`, 1 if `b` should be sorted
+ *          before `a`, 0 if they are equal. If two elements are equal, their
+ *          order in the sorted array is undefined.
+ *
+ * \since This callback is available since SDL 3.2.0.
+ *
+ * \sa SDL_qsort_r
+ * \sa SDL_bsearch_r
+ */
+typedef int (SDLCALL *SDL_CompareCallback_r)(void *userdata, const void *a, const void *b);
+/**
+ * Sort an array, passing a userdata pointer to the compare function.
+ *
+ * For example:
+ *
+ * ```c
+ * typedef enum {
+ *     sort_increasing,
+ *     sort_decreasing,
+ * } sort_method;
+ *
+ * typedef struct {
+ *     int key;
+ *     const char *string;
+ * } data;
+ *
+ * int SDLCALL compare(const void *userdata, const void *a, const void *b)
+ * {
+ *     sort_method method = (sort_method)(uintptr_t)userdata;
+ *     const data *A = (const data *)a;
+ *     const data *B = (const data *)b;
+ *
+ *     if (A->key < B->key) {
+ *         return (method == sort_increasing) ? -1 : 1;
+ *     } else if (B->key < A->key) {
+ *         return (method == sort_increasing) ? 1 : -1;
+ *     } else {
+ *         return 0;
+ *     }
+ * }
+ *
+ * data values[] = {
+ *     { 3, "third" }, { 1, "first" }, { 2, "second" }
+ * };
+ *
+ * SDL_qsort_r(values, SDL_arraysize(values), sizeof(values[0]), compare, (const void *)(uintptr_t)sort_increasing);
+ * ```
+ *
+ * \param base a pointer to the start of the array.
+ * \param nmemb the number of elements in the array.
+ * \param size the size of the elements in the array.
+ * \param compare a function used to compare elements in the array.
+ * \param userdata a pointer to pass to the compare function.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_bsearch_r
+ * \sa SDL_qsort
+ */
+extern SDL_DECLSPEC void SDLCALL SDL_qsort_r(void *base, size_t nmemb, size_t size, SDL_CompareCallback_r compare, void *userdata);
+/**
+ * Perform a binary search on a previously sorted array, passing a userdata
+ * pointer to the compare function.
+ *
+ * For example:
+ *
+ * ```c
+ * typedef enum {
+ *     sort_increasing,
+ *     sort_decreasing,
+ * } sort_method;
+ *
+ * typedef struct {
+ *     int key;
+ *     const char *string;
+ * } data;
+ *
+ * int SDLCALL compare(const void *userdata, const void *a, const void *b)
+ * {
+ *     sort_method method = (sort_method)(uintptr_t)userdata;
+ *     const data *A = (const data *)a;
+ *     const data *B = (const data *)b;
+ *
+ *     if (A->key < B->key) {
+ *         return (method == sort_increasing) ? -1 : 1;
+ *     } else if (B->key < A->key) {
+ *         return (method == sort_increasing) ? 1 : -1;
+ *     } else {
+ *         return 0;
+ *     }
+ * }
+ *
+ * data values[] = {
+ *     { 1, "first" }, { 2, "second" }, { 3, "third" }
+ * };
+ * data key = { 2, NULL };
+ *
+ * data *result = SDL_bsearch_r(&key, values, SDL_arraysize(values), sizeof(values[0]), compare, (const void *)(uintptr_t)sort_increasing);
+ * ```
+ *
+ * \param key a pointer to a key equal to the element being searched for.
+ * \param base a pointer to the start of the array.
+ * \param nmemb the number of elements in the array.
+ * \param size the size of the elements in the array.
+ * \param compare a function used to compare elements in the array.
+ * \param userdata a pointer to pass to the compare function.
+ * \returns a pointer to the matching element in the array, or NULL if not
+ *          found.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_bsearch
+ * \sa SDL_qsort_r
+ */
+extern SDL_DECLSPEC void * SDLCALL SDL_bsearch_r(const void *key, const void *base, size_t nmemb, size_t size, SDL_CompareCallback_r compare, void *userdata);
+/**
+ * Compute the absolute value of `x`.
+ *
+ * \param x an integer value.
+ * \returns the absolute value of x.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_abs(int x);
+/**
+ * Return the lesser of two values.
+ *
+ * This is a helper macro that might be more clear than writing out the
+ * comparisons directly, and works with any type that can be compared with the
+ * `<` operator. However, it double-evaluates both its parameters, so do not
+ * use expressions with side-effects here.
+ *
+ * \param x the first value to compare.
+ * \param y the second value to compare.
+ * \returns the lesser of `x` and `y`.
+ *
+ * \threadsafety It is safe to call this macro from any thread.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_min(x, y) (((x) < (y)) ? (x) : (y))
+/**
+ * Return the greater of two values.
+ *
+ * This is a helper macro that might be more clear than writing out the
+ * comparisons directly, and works with any type that can be compared with the
+ * `>` operator. However, it double-evaluates both its parameters, so do not
+ * use expressions with side-effects here.
+ *
+ * \param x the first value to compare.
+ * \param y the second value to compare.
+ * \returns the lesser of `x` and `y`.
+ *
+ * \threadsafety It is safe to call this macro from any thread.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_max(x, y) (((x) > (y)) ? (x) : (y))
+/**
+ * Return a value clamped to a range.
+ *
+ * If `x` is outside the range a values between `a` and `b`, the returned
+ * value will be `a` or `b` as appropriate. Otherwise, `x` is returned.
+ *
+ * This macro will produce incorrect results if `b` is less than `a`.
+ *
+ * This is a helper macro that might be more clear than writing out the
+ * comparisons directly, and works with any type that can be compared with the
+ * `<` and `>` operators. However, it double-evaluates all its parameters, so
+ * do not use expressions with side-effects here.
+ *
+ * \param x the value to compare.
+ * \param a the low end value.
+ * \param b the high end value.
+ * \returns x, clamped between a and b.
+ *
+ * \threadsafety It is safe to call this macro from any thread.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_clamp(x, a, b) (((x) < (a)) ? (a) : (((x) > (b)) ? (b) : (x)))
+/**
+ * Query if a character is alphabetic (a letter).
+ *
+ * **WARNING**: Regardless of system locale, this will only treat ASCII values
+ * for English 'a-z' and 'A-Z' as true.
+ *
+ * \param x character value to check.
+ * \returns non-zero if x falls within the character class, zero otherwise.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_isalpha(int x);
+/**
+ * Query if a character is alphabetic (a letter) or a number.
+ *
+ * **WARNING**: Regardless of system locale, this will only treat ASCII values
+ * for English 'a-z', 'A-Z', and '0-9' as true.
+ *
+ * \param x character value to check.
+ * \returns non-zero if x falls within the character class, zero otherwise.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_isalnum(int x);
+/**
+ * Report if a character is blank (a space or tab).
+ *
+ * **WARNING**: Regardless of system locale, this will only treat ASCII values
+ * 0x20 (space) or 0x9 (tab) as true.
+ *
+ * \param x character value to check.
+ * \returns non-zero if x falls within the character class, zero otherwise.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_isblank(int x);
+/**
+ * Report if a character is a control character.
+ *
+ * **WARNING**: Regardless of system locale, this will only treat ASCII values
+ * 0 through 0x1F, and 0x7F, as true.
+ *
+ * \param x character value to check.
+ * \returns non-zero if x falls within the character class, zero otherwise.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_iscntrl(int x);
+/**
+ * Report if a character is a numeric digit.
+ *
+ * **WARNING**: Regardless of system locale, this will only treat ASCII values
+ * '0' (0x30) through '9' (0x39), as true.
+ *
+ * \param x character value to check.
+ * \returns non-zero if x falls within the character class, zero otherwise.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_isdigit(int x);
+/**
+ * Report if a character is a hexadecimal digit.
+ *
+ * **WARNING**: Regardless of system locale, this will only treat ASCII values
+ * 'A' through 'F', 'a' through 'f', and '0' through '9', as true.
+ *
+ * \param x character value to check.
+ * \returns non-zero if x falls within the character class, zero otherwise.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_isxdigit(int x);
+/**
+ * Report if a character is a punctuation mark.
+ *
+ * **WARNING**: Regardless of system locale, this is equivalent to
+ * `((SDL_isgraph(x)) && (!SDL_isalnum(x)))`.
+ *
+ * \param x character value to check.
+ * \returns non-zero if x falls within the character class, zero otherwise.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_isgraph
+ * \sa SDL_isalnum
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_ispunct(int x);
+/**
+ * Report if a character is whitespace.
+ *
+ * **WARNING**: Regardless of system locale, this will only treat the
+ * following ASCII values as true:
+ *
+ * - space (0x20)
+ * - tab (0x09)
+ * - newline (0x0A)
+ * - vertical tab (0x0B)
+ * - form feed (0x0C)
+ * - return (0x0D)
+ *
+ * \param x character value to check.
+ * \returns non-zero if x falls within the character class, zero otherwise.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_isspace(int x);
+/**
+ * Report if a character is upper case.
+ *
+ * **WARNING**: Regardless of system locale, this will only treat ASCII values
+ * 'A' through 'Z' as true.
+ *
+ * \param x character value to check.
+ * \returns non-zero if x falls within the character class, zero otherwise.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_isupper(int x);
+/**
+ * Report if a character is lower case.
+ *
+ * **WARNING**: Regardless of system locale, this will only treat ASCII values
+ * 'a' through 'z' as true.
+ *
+ * \param x character value to check.
+ * \returns non-zero if x falls within the character class, zero otherwise.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_islower(int x);
+/**
+ * Report if a character is "printable".
+ *
+ * Be advised that "printable" has a definition that goes back to text
+ * terminals from the dawn of computing, making this a sort of special case
+ * function that is not suitable for Unicode (or most any) text management.
+ *
+ * **WARNING**: Regardless of system locale, this will only treat ASCII values
+ * ' ' (0x20) through '~' (0x7E) as true.
+ *
+ * \param x character value to check.
+ * \returns non-zero if x falls within the character class, zero otherwise.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_isprint(int x);
+/**
+ * Report if a character is any "printable" except space.
+ *
+ * Be advised that "printable" has a definition that goes back to text
+ * terminals from the dawn of computing, making this a sort of special case
+ * function that is not suitable for Unicode (or most any) text management.
+ *
+ * **WARNING**: Regardless of system locale, this is equivalent to
+ * `(SDL_isprint(x)) && ((x) != ' ')`.
+ *
+ * \param x character value to check.
+ * \returns non-zero if x falls within the character class, zero otherwise.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_isprint
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_isgraph(int x);
+/**
+ * Convert low-ASCII English letters to uppercase.
+ *
+ * **WARNING**: Regardless of system locale, this will only convert ASCII
+ * values 'a' through 'z' to uppercase.
+ *
+ * This function returns the uppercase equivalent of `x`. If a character
+ * cannot be converted, or is already uppercase, this function returns `x`.
+ *
+ * \param x character value to check.
+ * \returns capitalized version of x, or x if no conversion available.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_toupper(int x);
+/**
+ * Convert low-ASCII English letters to lowercase.
+ *
+ * **WARNING**: Regardless of system locale, this will only convert ASCII
+ * values 'A' through 'Z' to lowercase.
+ *
+ * This function returns the lowercase equivalent of `x`. If a character
+ * cannot be converted, or is already lowercase, this function returns `x`.
+ *
+ * \param x character value to check.
+ * \returns lowercase version of x, or x if no conversion available.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_tolower(int x);
+/**
+ * Calculate a CRC-16 value.
+ *
+ * https://en.wikipedia.org/wiki/Cyclic_redundancy_check
+ *
+ * This function can be called multiple times, to stream data to be
+ * checksummed in blocks. Each call must provide the previous CRC-16 return
+ * value to be updated with the next block. The first call to this function
+ * for a set of blocks should pass in a zero CRC value.
+ *
+ * \param crc the current checksum for this data set, or 0 for a new data set.
+ * \param data a new block of data to add to the checksum.
+ * \param len the size, in bytes, of the new block of data.
+ * \returns a CRC-16 checksum value of all blocks in the data set.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC Uint16 SDLCALL SDL_crc16(Uint16 crc, const void *data, size_t len);
+/**
+ * Calculate a CRC-32 value.
+ *
+ * https://en.wikipedia.org/wiki/Cyclic_redundancy_check
+ *
+ * This function can be called multiple times, to stream data to be
+ * checksummed in blocks. Each call must provide the previous CRC-32 return
+ * value to be updated with the next block. The first call to this function
+ * for a set of blocks should pass in a zero CRC value.
+ *
+ * \param crc the current checksum for this data set, or 0 for a new data set.
+ * \param data a new block of data to add to the checksum.
+ * \param len the size, in bytes, of the new block of data.
+ * \returns a CRC-32 checksum value of all blocks in the data set.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC Uint32 SDLCALL SDL_crc32(Uint32 crc, const void *data, size_t len);
+/**
+ * Calculate a 32-bit MurmurHash3 value for a block of data.
+ *
+ * https://en.wikipedia.org/wiki/MurmurHash
+ *
+ * A seed may be specified, which changes the final results consistently, but
+ * this does not work like SDL_crc16 and SDL_crc32: you can't feed a previous
+ * result from this function back into itself as the next seed value to
+ * calculate a hash in chunks; it won't produce the same hash as it would if
+ * the same data was provided in a single call.
+ *
+ * If you aren't sure what to provide for a seed, zero is fine. Murmur3 is not
+ * cryptographically secure, so it shouldn't be used for hashing top-secret
+ * data.
+ *
+ * \param data the data to be hashed.
+ * \param len the size of data, in bytes.
+ * \param seed a value that alters the final hash value.
+ * \returns a Murmur3 32-bit hash value.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC Uint32 SDLCALL SDL_murmur3_32(const void *data, size_t len, Uint32 seed);
+/**
+ * Copy non-overlapping memory.
+ *
+ * The memory regions must not overlap. If they do, use SDL_memmove() instead.
+ *
+ * \param dst The destination memory region. Must not be NULL, and must not
+ *            overlap with `src`.
+ * \param src The source memory region. Must not be NULL, and must not overlap
+ *            with `dst`.
+ * \param len The length in bytes of both `dst` and `src`.
+ * \returns `dst`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_memmove
+ */
+extern SDL_DECLSPEC void * SDLCALL SDL_memcpy(SDL_OUT_BYTECAP(len) void *dst, SDL_IN_BYTECAP(len) const void *src, size_t len);
+/* Take advantage of compiler optimizations for memcpy */
+#ifndef SDL_SLOW_MEMCPY
+#ifdef SDL_memcpy
+#undef SDL_memcpy
+#endif
+#define SDL_memcpy  memcpy
+#endif
+/**
+ * A macro to copy memory between objects, with basic type checking.
+ *
+ * SDL_memcpy and SDL_memmove do not care where you copy memory to and from,
+ * which can lead to bugs. This macro aims to avoid most of those bugs by
+ * making sure that the source and destination are both pointers to objects
+ * that are the same size. It does not check that the objects are the same
+ * _type_, just that the copy will not overflow either object.
+ *
+ * The size check happens at compile time, and the compiler will throw an
+ * error if the objects are different sizes.
+ *
+ * Generally this is intended to copy a single object, not an array.
+ *
+ * This macro looks like it double-evaluates its parameters, but the extras
+ * them are in `sizeof` sections, which generate no code nor side-effects.
+ *
+ * \param dst a pointer to the destination object. Must not be NULL.
+ * \param src a pointer to the source object. Must not be NULL.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+#define SDL_copyp(dst, src)                                                                 \
+    { SDL_COMPILE_TIME_ASSERT(SDL_copyp, sizeof (*(dst)) == sizeof (*(src))); }             \
+    SDL_memcpy((dst), (src), sizeof(*(src)))
+/**
+ * Copy memory ranges that might overlap.
+ *
+ * It is okay for the memory regions to overlap. If you are confident that the
+ * regions never overlap, using SDL_memcpy() may improve performance.
+ *
+ * \param dst The destination memory region. Must not be NULL.
+ * \param src The source memory region. Must not be NULL.
+ * \param len The length in bytes of both `dst` and `src`.
+ * \returns `dst`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_memcpy
+ */
+extern SDL_DECLSPEC void * SDLCALL SDL_memmove(SDL_OUT_BYTECAP(len) void *dst, SDL_IN_BYTECAP(len) const void *src, size_t len);
+/* Take advantage of compiler optimizations for memmove */
+#ifndef SDL_SLOW_MEMMOVE
+#ifdef SDL_memmove
+#undef SDL_memmove
+#endif
+#define SDL_memmove memmove
+#endif
+/**
+ * Initialize all bytes of buffer of memory to a specific value.
+ *
+ * This function will set `len` bytes, pointed to by `dst`, to the value
+ * specified in `c`.
+ *
+ * Despite `c` being an `int` instead of a `char`, this only operates on
+ * bytes; `c` must be a value between 0 and 255, inclusive.
+ *
+ * \param dst the destination memory region. Must not be NULL.
+ * \param c the byte value to set.
+ * \param len the length, in bytes, to set in `dst`.
+ * \returns `dst`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC void * SDLCALL SDL_memset(SDL_OUT_BYTECAP(len) void *dst, int c, size_t len);
+/**
+ * Initialize all 32-bit words of buffer of memory to a specific value.
+ *
+ * This function will set a buffer of `dwords` Uint32 values, pointed to by
+ * `dst`, to the value specified in `val`.
+ *
+ * Unlike SDL_memset, this sets 32-bit values, not bytes, so it's not limited
+ * to a range of 0-255.
+ *
+ * \param dst the destination memory region. Must not be NULL.
+ * \param val the Uint32 value to set.
+ * \param dwords the number of Uint32 values to set in `dst`.
+ * \returns `dst`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC void * SDLCALL SDL_memset4(void *dst, Uint32 val, size_t dwords);
+/* Take advantage of compiler optimizations for memset */
+#ifndef SDL_SLOW_MEMSET
+#ifdef SDL_memset
+#undef SDL_memset
+#endif
+#define SDL_memset  memset
+#endif
+/**
+ * Clear an object's memory to zero.
+ *
+ * This is wrapper over SDL_memset that handles calculating the object size,
+ * so there's no chance of copy/paste errors, and the code is cleaner.
+ *
+ * This requires an object, not a pointer to an object, nor an array.
+ *
+ * \param x the object to clear.
+ *
+ * \threadsafety It is safe to call this macro from any thread.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ *
+ * \sa SDL_zerop
+ * \sa SDL_zeroa
+ */
+#define SDL_zero(x) SDL_memset(&(x), 0, sizeof((x)))
+/**
+ * Clear an object's memory to zero, using a pointer.
+ *
+ * This is wrapper over SDL_memset that handles calculating the object size,
+ * so there's no chance of copy/paste errors, and the code is cleaner.
+ *
+ * This requires a pointer to an object, not an object itself, nor an array.
+ *
+ * \param x a pointer to the object to clear.
+ *
+ * \threadsafety It is safe to call this macro from any thread.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ *
+ * \sa SDL_zero
+ * \sa SDL_zeroa
+ */
+#define SDL_zerop(x) SDL_memset((x), 0, sizeof(*(x)))
+/**
+ * Clear an array's memory to zero.
+ *
+ * This is wrapper over SDL_memset that handles calculating the array size, so
+ * there's no chance of copy/paste errors, and the code is cleaner.
+ *
+ * This requires an array, not an object, nor a pointer to an object.
+ *
+ * \param x an array to clear.
+ *
+ * \threadsafety It is safe to call this macro from any thread.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ *
+ * \sa SDL_zero
+ * \sa SDL_zeroa
+ */
+#define SDL_zeroa(x) SDL_memset((x), 0, sizeof((x)))
+/**
+ * Compare two buffers of memory.
+ *
+ * \param s1 the first buffer to compare. NULL is not permitted!
+ * \param s2 the second buffer to compare. NULL is not permitted!
+ * \param len the number of bytes to compare between the buffers.
+ * \returns less than zero if s1 is "less than" s2, greater than zero if s1 is
+ *          "greater than" s2, and zero if the buffers match exactly for `len`
+ *          bytes.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_memcmp(const void *s1, const void *s2, size_t len);
+/**
+ * This works exactly like wcslen() but doesn't require access to a C runtime.
+ *
+ * Counts the number of wchar_t values in `wstr`, excluding the null
+ * terminator.
+ *
+ * Like SDL_strlen only counts bytes and not codepoints in a UTF-8 string,
+ * this counts wchar_t values in a string, even if the string's encoding is of
+ * variable width, like UTF-16.
+ *
+ * Also be aware that wchar_t is different sizes on different platforms (4
+ * bytes on Linux, 2 on Windows, etc).
+ *
+ * \param wstr The null-terminated wide string to read. Must not be NULL.
+ * \returns the length (in wchar_t values, excluding the null terminator) of
+ *          `wstr`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_wcsnlen
+ * \sa SDL_utf8strlen
+ * \sa SDL_utf8strnlen
+ */
+extern SDL_DECLSPEC size_t SDLCALL SDL_wcslen(const wchar_t *wstr);
+/**
+ * This works exactly like wcsnlen() but doesn't require access to a C
+ * runtime.
+ *
+ * Counts up to a maximum of `maxlen` wchar_t values in `wstr`, excluding the
+ * null terminator.
+ *
+ * Like SDL_strnlen only counts bytes and not codepoints in a UTF-8 string,
+ * this counts wchar_t values in a string, even if the string's encoding is of
+ * variable width, like UTF-16.
+ *
+ * Also be aware that wchar_t is different sizes on different platforms (4
+ * bytes on Linux, 2 on Windows, etc).
+ *
+ * Also, `maxlen` is a count of wide characters, not bytes!
+ *
+ * \param wstr The null-terminated wide string to read. Must not be NULL.
+ * \param maxlen The maximum amount of wide characters to count.
+ * \returns the length (in wide characters, excluding the null terminator) of
+ *          `wstr` but never more than `maxlen`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_wcslen
+ * \sa SDL_utf8strlen
+ * \sa SDL_utf8strnlen
+ */
+extern SDL_DECLSPEC size_t SDLCALL SDL_wcsnlen(const wchar_t *wstr, size_t maxlen);
+/**
+ * Copy a wide string.
+ *
+ * This function copies `maxlen` - 1 wide characters from `src` to `dst`, then
+ * appends a null terminator.
+ *
+ * `src` and `dst` must not overlap.
+ *
+ * If `maxlen` is 0, no wide characters are copied and no null terminator is
+ * written.
+ *
+ * \param dst The destination buffer. Must not be NULL, and must not overlap
+ *            with `src`.
+ * \param src The null-terminated wide string to copy. Must not be NULL, and
+ *            must not overlap with `dst`.
+ * \param maxlen The length (in wide characters) of the destination buffer.
+ * \returns the length (in wide characters, excluding the null terminator) of
+ *          `src`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_wcslcat
+ */
+extern SDL_DECLSPEC size_t SDLCALL SDL_wcslcpy(SDL_OUT_Z_CAP(maxlen) wchar_t *dst, const wchar_t *src, size_t maxlen);
+/**
+ * Concatenate wide strings.
+ *
+ * This function appends up to `maxlen` - SDL_wcslen(dst) - 1 wide characters
+ * from `src` to the end of the wide string in `dst`, then appends a null
+ * terminator.
+ *
+ * `src` and `dst` must not overlap.
+ *
+ * If `maxlen` - SDL_wcslen(dst) - 1 is less than or equal to 0, then `dst` is
+ * unmodified.
+ *
+ * \param dst The destination buffer already containing the first
+ *            null-terminated wide string. Must not be NULL and must not
+ *            overlap with `src`.
+ * \param src The second null-terminated wide string. Must not be NULL, and
+ *            must not overlap with `dst`.
+ * \param maxlen The length (in wide characters) of the destination buffer.
+ * \returns the length (in wide characters, excluding the null terminator) of
+ *          the string in `dst` plus the length of `src`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_wcslcpy
+ */
+extern SDL_DECLSPEC size_t SDLCALL SDL_wcslcat(SDL_INOUT_Z_CAP(maxlen) wchar_t *dst, const wchar_t *src, size_t maxlen);
+/**
+ * Allocate a copy of a wide string.
+ *
+ * This allocates enough space for a null-terminated copy of `wstr`, using
+ * SDL_malloc, and then makes a copy of the string into this space.
+ *
+ * The returned string is owned by the caller, and should be passed to
+ * SDL_free when no longer needed.
+ *
+ * \param wstr the string to copy.
+ * \returns a pointer to the newly-allocated wide string.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC wchar_t * SDLCALL SDL_wcsdup(const wchar_t *wstr);
+/**
+ * Search a wide string for the first instance of a specific substring.
+ *
+ * The search ends once it finds the requested substring, or a null terminator
+ * byte to end the string.
+ *
+ * Note that this looks for strings of _wide characters_, not _codepoints_, so
+ * it's legal to search for malformed and incomplete UTF-16 sequences.
+ *
+ * \param haystack the wide string to search. Must not be NULL.
+ * \param needle the wide string to search for. Must not be NULL.
+ * \returns a pointer to the first instance of `needle` in the string, or NULL
+ *          if not found.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC wchar_t * SDLCALL SDL_wcsstr(const wchar_t *haystack, const wchar_t *needle);
+/**
+ * Search a wide string, up to n wide chars, for the first instance of a
+ * specific substring.
+ *
+ * The search ends once it finds the requested substring, or a null terminator
+ * value to end the string, or `maxlen` wide character have been examined. It
+ * is possible to use this function on a wide string without a null
+ * terminator.
+ *
+ * Note that this looks for strings of _wide characters_, not _codepoints_, so
+ * it's legal to search for malformed and incomplete UTF-16 sequences.
+ *
+ * \param haystack the wide string to search. Must not be NULL.
+ * \param needle the wide string to search for. Must not be NULL.
+ * \param maxlen the maximum number of wide characters to search in
+ *               `haystack`.
+ * \returns a pointer to the first instance of `needle` in the string, or NULL
+ *          if not found.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC wchar_t * SDLCALL SDL_wcsnstr(const wchar_t *haystack, const wchar_t *needle, size_t maxlen);
+/**
+ * Compare two null-terminated wide strings.
+ *
+ * This only compares wchar_t values until it hits a null-terminating
+ * character; it does not care if the string is well-formed UTF-16 (or UTF-32,
+ * depending on your platform's wchar_t size), or uses valid Unicode values.
+ *
+ * \param str1 the first string to compare. NULL is not permitted!
+ * \param str2 the second string to compare. NULL is not permitted!
+ * \returns less than zero if str1 is "less than" str2, greater than zero if
+ *          str1 is "greater than" str2, and zero if the strings match
+ *          exactly.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_wcscmp(const wchar_t *str1, const wchar_t *str2);
+/**
+ * Compare two wide strings up to a number of wchar_t values.
+ *
+ * This only compares wchar_t values; it does not care if the string is
+ * well-formed UTF-16 (or UTF-32, depending on your platform's wchar_t size),
+ * or uses valid Unicode values.
+ *
+ * Note that while this function is intended to be used with UTF-16 (or
+ * UTF-32, depending on your platform's definition of wchar_t), it is
+ * comparing raw wchar_t values and not Unicode codepoints: `maxlen` specifies
+ * a wchar_t limit! If the limit lands in the middle of a multi-wchar UTF-16
+ * sequence, it will only compare a portion of the final character.
+ *
+ * `maxlen` specifies a maximum number of wchar_t to compare; if the strings
+ * match to this number of wide chars (or both have matched to a
+ * null-terminator character before this count), they will be considered
+ * equal.
+ *
+ * \param str1 the first string to compare. NULL is not permitted!
+ * \param str2 the second string to compare. NULL is not permitted!
+ * \param maxlen the maximum number of wchar_t to compare.
+ * \returns less than zero if str1 is "less than" str2, greater than zero if
+ *          str1 is "greater than" str2, and zero if the strings match
+ *          exactly.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_wcsncmp(const wchar_t *str1, const wchar_t *str2, size_t maxlen);
+/**
+ * Compare two null-terminated wide strings, case-insensitively.
+ *
+ * This will work with Unicode strings, using a technique called
+ * "case-folding" to handle the vast majority of case-sensitive human
+ * languages regardless of system locale. It can deal with expanding values: a
+ * German Eszett character can compare against two ASCII 's' chars and be
+ * considered a match, for example. A notable exception: it does not handle
+ * the Turkish 'i' character; human language is complicated!
+ *
+ * Depending on your platform, "wchar_t" might be 2 bytes, and expected to be
+ * UTF-16 encoded (like Windows), or 4 bytes in UTF-32 format. Since this
+ * handles Unicode, it expects the string to be well-formed and not a
+ * null-terminated string of arbitrary bytes. Characters that are not valid
+ * UTF-16 (or UTF-32) are treated as Unicode character U+FFFD (REPLACEMENT
+ * CHARACTER), which is to say two strings of random bits may turn out to
+ * match if they convert to the same amount of replacement characters.
+ *
+ * \param str1 the first string to compare. NULL is not permitted!
+ * \param str2 the second string to compare. NULL is not permitted!
+ * \returns less than zero if str1 is "less than" str2, greater than zero if
+ *          str1 is "greater than" str2, and zero if the strings match
+ *          exactly.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_wcscasecmp(const wchar_t *str1, const wchar_t *str2);
+/**
+ * Compare two wide strings, case-insensitively, up to a number of wchar_t.
+ *
+ * This will work with Unicode strings, using a technique called
+ * "case-folding" to handle the vast majority of case-sensitive human
+ * languages regardless of system locale. It can deal with expanding values: a
+ * German Eszett character can compare against two ASCII 's' chars and be
+ * considered a match, for example. A notable exception: it does not handle
+ * the Turkish 'i' character; human language is complicated!
+ *
+ * Depending on your platform, "wchar_t" might be 2 bytes, and expected to be
+ * UTF-16 encoded (like Windows), or 4 bytes in UTF-32 format. Since this
+ * handles Unicode, it expects the string to be well-formed and not a
+ * null-terminated string of arbitrary bytes. Characters that are not valid
+ * UTF-16 (or UTF-32) are treated as Unicode character U+FFFD (REPLACEMENT
+ * CHARACTER), which is to say two strings of random bits may turn out to
+ * match if they convert to the same amount of replacement characters.
+ *
+ * Note that while this function might deal with variable-sized characters,
+ * `maxlen` specifies a _wchar_ limit! If the limit lands in the middle of a
+ * multi-byte UTF-16 sequence, it may convert a portion of the final character
+ * to one or more Unicode character U+FFFD (REPLACEMENT CHARACTER) so as not
+ * to overflow a buffer.
+ *
+ * `maxlen` specifies a maximum number of wchar_t values to compare; if the
+ * strings match to this number of wchar_t (or both have matched to a
+ * null-terminator character before this number of bytes), they will be
+ * considered equal.
+ *
+ * \param str1 the first string to compare. NULL is not permitted!
+ * \param str2 the second string to compare. NULL is not permitted!
+ * \param maxlen the maximum number of wchar_t values to compare.
+ * \returns less than zero if str1 is "less than" str2, greater than zero if
+ *          str1 is "greater than" str2, and zero if the strings match
+ *          exactly.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_wcsncasecmp(const wchar_t *str1, const wchar_t *str2, size_t maxlen);
+/**
+ * Parse a `long` from a wide string.
+ *
+ * If `str` starts with whitespace, then those whitespace characters are
+ * skipped before attempting to parse the number.
+ *
+ * If the parsed number does not fit inside a `long`, the result is clamped to
+ * the minimum and maximum representable `long` values.
+ *
+ * \param str The null-terminated wide string to read. Must not be NULL.
+ * \param endp If not NULL, the address of the first invalid wide character
+ *             (i.e. the next character after the parsed number) will be
+ *             written to this pointer.
+ * \param base The base of the integer to read. Supported values are 0 and 2
+ *             to 36 inclusive. If 0, the base will be inferred from the
+ *             number's prefix (0x for hexadecimal, 0 for octal, decimal
+ *             otherwise).
+ * \returns the parsed `long`, or 0 if no number could be parsed.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_strtol
+ */
+extern SDL_DECLSPEC long SDLCALL SDL_wcstol(const wchar_t *str, wchar_t **endp, int base);
+/**
+ * This works exactly like strlen() but doesn't require access to a C runtime.
+ *
+ * Counts the bytes in `str`, excluding the null terminator.
+ *
+ * If you need the length of a UTF-8 string, consider using SDL_utf8strlen().
+ *
+ * \param str The null-terminated string to read. Must not be NULL.
+ * \returns the length (in bytes, excluding the null terminator) of `src`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_strnlen
+ * \sa SDL_utf8strlen
+ * \sa SDL_utf8strnlen
+ */
+extern SDL_DECLSPEC size_t SDLCALL SDL_strlen(const char *str);
+/**
+ * This works exactly like strnlen() but doesn't require access to a C
+ * runtime.
+ *
+ * Counts up to a maximum of `maxlen` bytes in `str`, excluding the null
+ * terminator.
+ *
+ * If you need the length of a UTF-8 string, consider using SDL_utf8strnlen().
+ *
+ * \param str The null-terminated string to read. Must not be NULL.
+ * \param maxlen The maximum amount of bytes to count.
+ * \returns the length (in bytes, excluding the null terminator) of `src` but
+ *          never more than `maxlen`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_strlen
+ * \sa SDL_utf8strlen
+ * \sa SDL_utf8strnlen
+ */
+extern SDL_DECLSPEC size_t SDLCALL SDL_strnlen(const char *str, size_t maxlen);
+/**
+ * Copy a string.
+ *
+ * This function copies up to `maxlen` - 1 characters from `src` to `dst`,
+ * then appends a null terminator.
+ *
+ * If `maxlen` is 0, no characters are copied and no null terminator is
+ * written.
+ *
+ * If you want to copy an UTF-8 string but need to ensure that multi-byte
+ * sequences are not truncated, consider using SDL_utf8strlcpy().
+ *
+ * \param dst The destination buffer. Must not be NULL, and must not overlap
+ *            with `src`.
+ * \param src The null-terminated string to copy. Must not be NULL, and must
+ *            not overlap with `dst`.
+ * \param maxlen The length (in characters) of the destination buffer.
+ * \returns the length (in characters, excluding the null terminator) of
+ *          `src`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_strlcat
+ * \sa SDL_utf8strlcpy
+ */
+extern SDL_DECLSPEC size_t SDLCALL SDL_strlcpy(SDL_OUT_Z_CAP(maxlen) char *dst, const char *src, size_t maxlen);
+/**
+ * Copy an UTF-8 string.
+ *
+ * This function copies up to `dst_bytes` - 1 bytes from `src` to `dst` while
+ * also ensuring that the string written to `dst` does not end in a truncated
+ * multi-byte sequence. Finally, it appends a null terminator.
+ *
+ * `src` and `dst` must not overlap.
+ *
+ * Note that unlike SDL_strlcpy(), this function returns the number of bytes
+ * written, not the length of `src`.
+ *
+ * \param dst The destination buffer. Must not be NULL, and must not overlap
+ *            with `src`.
+ * \param src The null-terminated UTF-8 string to copy. Must not be NULL, and
+ *            must not overlap with `dst`.
+ * \param dst_bytes The length (in bytes) of the destination buffer. Must not
+ *                  be 0.
+ * \returns the number of bytes written, excluding the null terminator.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_strlcpy
+ */
+extern SDL_DECLSPEC size_t SDLCALL SDL_utf8strlcpy(SDL_OUT_Z_CAP(dst_bytes) char *dst, const char *src, size_t dst_bytes);
+/**
+ * Concatenate strings.
+ *
+ * This function appends up to `maxlen` - SDL_strlen(dst) - 1 characters from
+ * `src` to the end of the string in `dst`, then appends a null terminator.
+ *
+ * `src` and `dst` must not overlap.
+ *
+ * If `maxlen` - SDL_strlen(dst) - 1 is less than or equal to 0, then `dst` is
+ * unmodified.
+ *
+ * \param dst The destination buffer already containing the first
+ *            null-terminated string. Must not be NULL and must not overlap
+ *            with `src`.
+ * \param src The second null-terminated string. Must not be NULL, and must
+ *            not overlap with `dst`.
+ * \param maxlen The length (in characters) of the destination buffer.
+ * \returns the length (in characters, excluding the null terminator) of the
+ *          string in `dst` plus the length of `src`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_strlcpy
+ */
+extern SDL_DECLSPEC size_t SDLCALL SDL_strlcat(SDL_INOUT_Z_CAP(maxlen) char *dst, const char *src, size_t maxlen);
+/**
+ * Allocate a copy of a string.
+ *
+ * This allocates enough space for a null-terminated copy of `str`, using
+ * SDL_malloc, and then makes a copy of the string into this space.
+ *
+ * The returned string is owned by the caller, and should be passed to
+ * SDL_free when no longer needed.
+ *
+ * \param str the string to copy.
+ * \returns a pointer to the newly-allocated string.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC SDL_MALLOC char * SDLCALL SDL_strdup(const char *str);
+/**
+ * Allocate a copy of a string, up to n characters.
+ *
+ * This allocates enough space for a null-terminated copy of `str`, up to
+ * `maxlen` bytes, using SDL_malloc, and then makes a copy of the string into
+ * this space.
+ *
+ * If the string is longer than `maxlen` bytes, the returned string will be
+ * `maxlen` bytes long, plus a null-terminator character that isn't included
+ * in the count.
+ *
+ * The returned string is owned by the caller, and should be passed to
+ * SDL_free when no longer needed.
+ *
+ * \param str the string to copy.
+ * \param maxlen the maximum length of the copied string, not counting the
+ *               null-terminator character.
+ * \returns a pointer to the newly-allocated string.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC SDL_MALLOC char * SDLCALL SDL_strndup(const char *str, size_t maxlen);
+/**
+ * Reverse a string's contents.
+ *
+ * This reverses a null-terminated string in-place. Only the content of the
+ * string is reversed; the null-terminator character remains at the end of the
+ * reversed string.
+ *
+ * **WARNING**: This function reverses the _bytes_ of the string, not the
+ * codepoints. If `str` is a UTF-8 string with Unicode codepoints > 127, this
+ * will ruin the string data. You should only use this function on strings
+ * that are completely comprised of low ASCII characters.
+ *
+ * \param str the string to reverse.
+ * \returns `str`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC char * SDLCALL SDL_strrev(char *str);
+/**
+ * Convert a string to uppercase.
+ *
+ * **WARNING**: Regardless of system locale, this will only convert ASCII
+ * values 'A' through 'Z' to uppercase.
+ *
+ * This function operates on a null-terminated string of bytes--even if it is
+ * malformed UTF-8!--and converts ASCII characters 'a' through 'z' to their
+ * uppercase equivalents in-place, returning the original `str` pointer.
+ *
+ * \param str the string to convert in-place. Can not be NULL.
+ * \returns the `str` pointer passed into this function.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_strlwr
+ */
+extern SDL_DECLSPEC char * SDLCALL SDL_strupr(char *str);
+/**
+ * Convert a string to lowercase.
+ *
+ * **WARNING**: Regardless of system locale, this will only convert ASCII
+ * values 'A' through 'Z' to lowercase.
+ *
+ * This function operates on a null-terminated string of bytes--even if it is
+ * malformed UTF-8!--and converts ASCII characters 'A' through 'Z' to their
+ * lowercase equivalents in-place, returning the original `str` pointer.
+ *
+ * \param str the string to convert in-place. Can not be NULL.
+ * \returns the `str` pointer passed into this function.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_strupr
+ */
+extern SDL_DECLSPEC char * SDLCALL SDL_strlwr(char *str);
+/**
+ * Search a string for the first instance of a specific byte.
+ *
+ * The search ends once it finds the requested byte value, or a null
+ * terminator byte to end the string.
+ *
+ * Note that this looks for _bytes_, not _characters_, so you cannot match
+ * against a Unicode codepoint > 255, regardless of character encoding.
+ *
+ * \param str the string to search. Must not be NULL.
+ * \param c the byte value to search for.
+ * \returns a pointer to the first instance of `c` in the string, or NULL if
+ *          not found.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC char * SDLCALL SDL_strchr(const char *str, int c);
+/**
+ * Search a string for the last instance of a specific byte.
+ *
+ * The search must go until it finds a null terminator byte to end the string.
+ *
+ * Note that this looks for _bytes_, not _characters_, so you cannot match
+ * against a Unicode codepoint > 255, regardless of character encoding.
+ *
+ * \param str the string to search. Must not be NULL.
+ * \param c the byte value to search for.
+ * \returns a pointer to the last instance of `c` in the string, or NULL if
+ *          not found.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC char * SDLCALL SDL_strrchr(const char *str, int c);
+/**
+ * Search a string for the first instance of a specific substring.
+ *
+ * The search ends once it finds the requested substring, or a null terminator
+ * byte to end the string.
+ *
+ * Note that this looks for strings of _bytes_, not _characters_, so it's
+ * legal to search for malformed and incomplete UTF-8 sequences.
+ *
+ * \param haystack the string to search. Must not be NULL.
+ * \param needle the string to search for. Must not be NULL.
+ * \returns a pointer to the first instance of `needle` in the string, or NULL
+ *          if not found.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC char * SDLCALL SDL_strstr(const char *haystack, const char *needle);
+/**
+ * Search a string, up to n bytes, for the first instance of a specific
+ * substring.
+ *
+ * The search ends once it finds the requested substring, or a null terminator
+ * byte to end the string, or `maxlen` bytes have been examined. It is
+ * possible to use this function on a string without a null terminator.
+ *
+ * Note that this looks for strings of _bytes_, not _characters_, so it's
+ * legal to search for malformed and incomplete UTF-8 sequences.
+ *
+ * \param haystack the string to search. Must not be NULL.
+ * \param needle the string to search for. Must not be NULL.
+ * \param maxlen the maximum number of bytes to search in `haystack`.
+ * \returns a pointer to the first instance of `needle` in the string, or NULL
+ *          if not found.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC char * SDLCALL SDL_strnstr(const char *haystack, const char *needle, size_t maxlen);
+/**
+ * Search a UTF-8 string for the first instance of a specific substring,
+ * case-insensitively.
+ *
+ * This will work with Unicode strings, using a technique called
+ * "case-folding" to handle the vast majority of case-sensitive human
+ * languages regardless of system locale. It can deal with expanding values: a
+ * German Eszett character can compare against two ASCII 's' chars and be
+ * considered a match, for example. A notable exception: it does not handle
+ * the Turkish 'i' character; human language is complicated!
+ *
+ * Since this handles Unicode, it expects the strings to be well-formed UTF-8
+ * and not a null-terminated string of arbitrary bytes. Bytes that are not
+ * valid UTF-8 are treated as Unicode character U+FFFD (REPLACEMENT
+ * CHARACTER), which is to say two strings of random bits may turn out to
+ * match if they convert to the same amount of replacement characters.
+ *
+ * \param haystack the string to search. Must not be NULL.
+ * \param needle the string to search for. Must not be NULL.
+ * \returns a pointer to the first instance of `needle` in the string, or NULL
+ *          if not found.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC char * SDLCALL SDL_strcasestr(const char *haystack, const char *needle);
+/**
+ * This works exactly like strtok_r() but doesn't require access to a C
+ * runtime.
+ *
+ * Break a string up into a series of tokens.
+ *
+ * To start tokenizing a new string, `str` should be the non-NULL address of
+ * the string to start tokenizing. Future calls to get the next token from the
+ * same string should specify a NULL.
+ *
+ * Note that this function will overwrite pieces of `str` with null chars to
+ * split it into tokens. This function cannot be used with const/read-only
+ * strings!
+ *
+ * `saveptr` just needs to point to a `char *` that can be overwritten; SDL
+ * will use this to save tokenizing state between calls. It is initialized if
+ * `str` is non-NULL, and used to resume tokenizing when `str` is NULL.
+ *
+ * \param str the string to tokenize, or NULL to continue tokenizing.
+ * \param delim the delimiter string that separates tokens.
+ * \param saveptr pointer to a char *, used for ongoing state.
+ * \returns A pointer to the next token, or NULL if no tokens remain.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC char * SDLCALL SDL_strtok_r(char *str, const char *delim, char **saveptr);
+/**
+ * Count the number of codepoints in a UTF-8 string.
+ *
+ * Counts the _codepoints_, not _bytes_, in `str`, excluding the null
+ * terminator.
+ *
+ * If you need to count the bytes in a string instead, consider using
+ * SDL_strlen().
+ *
+ * Since this handles Unicode, it expects the strings to be well-formed UTF-8
+ * and not a null-terminated string of arbitrary bytes. Bytes that are not
+ * valid UTF-8 are treated as Unicode character U+FFFD (REPLACEMENT
+ * CHARACTER), so a malformed or incomplete UTF-8 sequence might increase the
+ * count by several replacement characters.
+ *
+ * \param str The null-terminated UTF-8 string to read. Must not be NULL.
+ * \returns The length (in codepoints, excluding the null terminator) of
+ *          `src`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_utf8strnlen
+ * \sa SDL_strlen
+ */
+extern SDL_DECLSPEC size_t SDLCALL SDL_utf8strlen(const char *str);
+/**
+ * Count the number of codepoints in a UTF-8 string, up to n bytes.
+ *
+ * Counts the _codepoints_, not _bytes_, in `str`, excluding the null
+ * terminator.
+ *
+ * If you need to count the bytes in a string instead, consider using
+ * SDL_strnlen().
+ *
+ * The counting stops at `bytes` bytes (not codepoints!). This seems
+ * counterintuitive, but makes it easy to express the total size of the
+ * string's buffer.
+ *
+ * Since this handles Unicode, it expects the strings to be well-formed UTF-8
+ * and not a null-terminated string of arbitrary bytes. Bytes that are not
+ * valid UTF-8 are treated as Unicode character U+FFFD (REPLACEMENT
+ * CHARACTER), so a malformed or incomplete UTF-8 sequence might increase the
+ * count by several replacement characters.
+ *
+ * \param str The null-terminated UTF-8 string to read. Must not be NULL.
+ * \param bytes The maximum amount of bytes to count.
+ * \returns The length (in codepoints, excluding the null terminator) of `src`
+ *          but never more than `maxlen`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_utf8strlen
+ * \sa SDL_strnlen
+ */
+extern SDL_DECLSPEC size_t SDLCALL SDL_utf8strnlen(const char *str, size_t bytes);
+/**
+ * Convert an integer into a string.
+ *
+ * This requires a radix to specified for string format. Specifying 10
+ * produces a decimal number, 16 hexidecimal, etc. Must be in the range of 2
+ * to 36.
+ *
+ * Note that this function will overflow a buffer if `str` is not large enough
+ * to hold the output! It may be safer to use SDL_snprintf to clamp output, or
+ * SDL_asprintf to allocate a buffer. Otherwise, it doesn't hurt to allocate
+ * much more space than you expect to use (and don't forget possible negative
+ * signs, null terminator bytes, etc).
+ *
+ * \param value the integer to convert.
+ * \param str the buffer to write the string into.
+ * \param radix the radix to use for string generation.
+ * \returns `str`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_uitoa
+ * \sa SDL_ltoa
+ * \sa SDL_lltoa
+ */
+extern SDL_DECLSPEC char * SDLCALL SDL_itoa(int value, char *str, int radix);
+/**
+ * Convert an unsigned integer into a string.
+ *
+ * This requires a radix to specified for string format. Specifying 10
+ * produces a decimal number, 16 hexidecimal, etc. Must be in the range of 2
+ * to 36.
+ *
+ * Note that this function will overflow a buffer if `str` is not large enough
+ * to hold the output! It may be safer to use SDL_snprintf to clamp output, or
+ * SDL_asprintf to allocate a buffer. Otherwise, it doesn't hurt to allocate
+ * much more space than you expect to use (and don't forget null terminator
+ * bytes, etc).
+ *
+ * \param value the unsigned integer to convert.
+ * \param str the buffer to write the string into.
+ * \param radix the radix to use for string generation.
+ * \returns `str`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_itoa
+ * \sa SDL_ultoa
+ * \sa SDL_ulltoa
+ */
+extern SDL_DECLSPEC char * SDLCALL SDL_uitoa(unsigned int value, char *str, int radix);
+/**
+ * Convert a long integer into a string.
+ *
+ * This requires a radix to specified for string format. Specifying 10
+ * produces a decimal number, 16 hexidecimal, etc. Must be in the range of 2
+ * to 36.
+ *
+ * Note that this function will overflow a buffer if `str` is not large enough
+ * to hold the output! It may be safer to use SDL_snprintf to clamp output, or
+ * SDL_asprintf to allocate a buffer. Otherwise, it doesn't hurt to allocate
+ * much more space than you expect to use (and don't forget possible negative
+ * signs, null terminator bytes, etc).
+ *
+ * \param value the long integer to convert.
+ * \param str the buffer to write the string into.
+ * \param radix the radix to use for string generation.
+ * \returns `str`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_ultoa
+ * \sa SDL_itoa
+ * \sa SDL_lltoa
+ */
+extern SDL_DECLSPEC char * SDLCALL SDL_ltoa(long value, char *str, int radix);
+/**
+ * Convert an unsigned long integer into a string.
+ *
+ * This requires a radix to specified for string format. Specifying 10
+ * produces a decimal number, 16 hexidecimal, etc. Must be in the range of 2
+ * to 36.
+ *
+ * Note that this function will overflow a buffer if `str` is not large enough
+ * to hold the output! It may be safer to use SDL_snprintf to clamp output, or
+ * SDL_asprintf to allocate a buffer. Otherwise, it doesn't hurt to allocate
+ * much more space than you expect to use (and don't forget null terminator
+ * bytes, etc).
+ *
+ * \param value the unsigned long integer to convert.
+ * \param str the buffer to write the string into.
+ * \param radix the radix to use for string generation.
+ * \returns `str`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_ltoa
+ * \sa SDL_uitoa
+ * \sa SDL_ulltoa
+ */
+extern SDL_DECLSPEC char * SDLCALL SDL_ultoa(unsigned long value, char *str, int radix);
+#ifndef SDL_NOLONGLONG
+/**
+ * Convert a long long integer into a string.
+ *
+ * This requires a radix to specified for string format. Specifying 10
+ * produces a decimal number, 16 hexidecimal, etc. Must be in the range of 2
+ * to 36.
+ *
+ * Note that this function will overflow a buffer if `str` is not large enough
+ * to hold the output! It may be safer to use SDL_snprintf to clamp output, or
+ * SDL_asprintf to allocate a buffer. Otherwise, it doesn't hurt to allocate
+ * much more space than you expect to use (and don't forget possible negative
+ * signs, null terminator bytes, etc).
+ *
+ * \param value the long long integer to convert.
+ * \param str the buffer to write the string into.
+ * \param radix the radix to use for string generation.
+ * \returns `str`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_ulltoa
+ * \sa SDL_itoa
+ * \sa SDL_ltoa
+ */
+extern SDL_DECLSPEC char * SDLCALL SDL_lltoa(long long value, char *str, int radix);
+/**
+ * Convert an unsigned long long integer into a string.
+ *
+ * This requires a radix to specified for string format. Specifying 10
+ * produces a decimal number, 16 hexidecimal, etc. Must be in the range of 2
+ * to 36.
+ *
+ * Note that this function will overflow a buffer if `str` is not large enough
+ * to hold the output! It may be safer to use SDL_snprintf to clamp output, or
+ * SDL_asprintf to allocate a buffer. Otherwise, it doesn't hurt to allocate
+ * much more space than you expect to use (and don't forget null terminator
+ * bytes, etc).
+ *
+ * \param value the unsigned long long integer to convert.
+ * \param str the buffer to write the string into.
+ * \param radix the radix to use for string generation.
+ * \returns `str`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_lltoa
+ * \sa SDL_uitoa
+ * \sa SDL_ultoa
+ */
+extern SDL_DECLSPEC char * SDLCALL SDL_ulltoa(unsigned long long value, char *str, int radix);
+#endif
+/**
+ * Parse an `int` from a string.
+ *
+ * The result of calling `SDL_atoi(str)` is equivalent to
+ * `(int)SDL_strtol(str, NULL, 10)`.
+ *
+ * \param str The null-terminated string to read. Must not be NULL.
+ * \returns the parsed `int`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_atof
+ * \sa SDL_strtol
+ * \sa SDL_strtoul
+ * \sa SDL_strtoll
+ * \sa SDL_strtoull
+ * \sa SDL_strtod
+ * \sa SDL_itoa
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_atoi(const char *str);
+/**
+ * Parse a `double` from a string.
+ *
+ * The result of calling `SDL_atof(str)` is equivalent to `SDL_strtod(str,
+ * NULL)`.
+ *
+ * \param str The null-terminated string to read. Must not be NULL.
+ * \returns the parsed `double`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_atoi
+ * \sa SDL_strtol
+ * \sa SDL_strtoul
+ * \sa SDL_strtoll
+ * \sa SDL_strtoull
+ * \sa SDL_strtod
+ */
+extern SDL_DECLSPEC double SDLCALL SDL_atof(const char *str);
+/**
+ * Parse a `long` from a string.
+ *
+ * If `str` starts with whitespace, then those whitespace characters are
+ * skipped before attempting to parse the number.
+ *
+ * If the parsed number does not fit inside a `long`, the result is clamped to
+ * the minimum and maximum representable `long` values.
+ *
+ * \param str The null-terminated string to read. Must not be NULL.
+ * \param endp If not NULL, the address of the first invalid character (i.e.
+ *             the next character after the parsed number) will be written to
+ *             this pointer.
+ * \param base The base of the integer to read. Supported values are 0 and 2
+ *             to 36 inclusive. If 0, the base will be inferred from the
+ *             number's prefix (0x for hexadecimal, 0 for octal, decimal
+ *             otherwise).
+ * \returns the parsed `long`, or 0 if no number could be parsed.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_atoi
+ * \sa SDL_atof
+ * \sa SDL_strtoul
+ * \sa SDL_strtoll
+ * \sa SDL_strtoull
+ * \sa SDL_strtod
+ * \sa SDL_ltoa
+ * \sa SDL_wcstol
+ */
+extern SDL_DECLSPEC long SDLCALL SDL_strtol(const char *str, char **endp, int base);
+/**
+ * Parse an `unsigned long` from a string.
+ *
+ * If `str` starts with whitespace, then those whitespace characters are
+ * skipped before attempting to parse the number.
+ *
+ * If the parsed number does not fit inside an `unsigned long`, the result is
+ * clamped to the maximum representable `unsigned long` value.
+ *
+ * \param str The null-terminated string to read. Must not be NULL.
+ * \param endp If not NULL, the address of the first invalid character (i.e.
+ *             the next character after the parsed number) will be written to
+ *             this pointer.
+ * \param base The base of the integer to read. Supported values are 0 and 2
+ *             to 36 inclusive. If 0, the base will be inferred from the
+ *             number's prefix (0x for hexadecimal, 0 for octal, decimal
+ *             otherwise).
+ * \returns the parsed `unsigned long`, or 0 if no number could be parsed.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_atoi
+ * \sa SDL_atof
+ * \sa SDL_strtol
+ * \sa SDL_strtoll
+ * \sa SDL_strtoull
+ * \sa SDL_strtod
+ * \sa SDL_ultoa
+ */
+extern SDL_DECLSPEC unsigned long SDLCALL SDL_strtoul(const char *str, char **endp, int base);
+#ifndef SDL_NOLONGLONG
+/**
+ * Parse a `long long` from a string.
+ *
+ * If `str` starts with whitespace, then those whitespace characters are
+ * skipped before attempting to parse the number.
+ *
+ * If the parsed number does not fit inside a `long long`, the result is
+ * clamped to the minimum and maximum representable `long long` values.
+ *
+ * \param str The null-terminated string to read. Must not be NULL.
+ * \param endp If not NULL, the address of the first invalid character (i.e.
+ *             the next character after the parsed number) will be written to
+ *             this pointer.
+ * \param base The base of the integer to read. Supported values are 0 and 2
+ *             to 36 inclusive. If 0, the base will be inferred from the
+ *             number's prefix (0x for hexadecimal, 0 for octal, decimal
+ *             otherwise).
+ * \returns the parsed `long long`, or 0 if no number could be parsed.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_atoi
+ * \sa SDL_atof
+ * \sa SDL_strtol
+ * \sa SDL_strtoul
+ * \sa SDL_strtoull
+ * \sa SDL_strtod
+ * \sa SDL_lltoa
+ */
+extern SDL_DECLSPEC long long SDLCALL SDL_strtoll(const char *str, char **endp, int base);
+/**
+ * Parse an `unsigned long long` from a string.
+ *
+ * If `str` starts with whitespace, then those whitespace characters are
+ * skipped before attempting to parse the number.
+ *
+ * If the parsed number does not fit inside an `unsigned long long`, the
+ * result is clamped to the maximum representable `unsigned long long` value.
+ *
+ * \param str The null-terminated string to read. Must not be NULL.
+ * \param endp If not NULL, the address of the first invalid character (i.e.
+ *             the next character after the parsed number) will be written to
+ *             this pointer.
+ * \param base The base of the integer to read. Supported values are 0 and 2
+ *             to 36 inclusive. If 0, the base will be inferred from the
+ *             number's prefix (0x for hexadecimal, 0 for octal, decimal
+ *             otherwise).
+ * \returns the parsed `unsigned long long`, or 0 if no number could be
+ *          parsed.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_atoi
+ * \sa SDL_atof
+ * \sa SDL_strtol
+ * \sa SDL_strtoll
+ * \sa SDL_strtoul
+ * \sa SDL_strtod
+ * \sa SDL_ulltoa
+ */
+extern SDL_DECLSPEC unsigned long long SDLCALL SDL_strtoull(const char *str, char **endp, int base);
+#endif
+/**
+ * Parse a `double` from a string.
+ *
+ * This function makes fewer guarantees than the C runtime `strtod`:
+ *
+ * - Only decimal notation is guaranteed to be supported. The handling of
+ *   scientific and hexadecimal notation is unspecified.
+ * - Whether or not INF and NAN can be parsed is unspecified.
+ * - The precision of the result is unspecified.
+ *
+ * \param str the null-terminated string to read. Must not be NULL.
+ * \param endp if not NULL, the address of the first invalid character (i.e.
+ *             the next character after the parsed number) will be written to
+ *             this pointer.
+ * \returns the parsed `double`, or 0 if no number could be parsed.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_atoi
+ * \sa SDL_atof
+ * \sa SDL_strtol
+ * \sa SDL_strtoll
+ * \sa SDL_strtoul
+ * \sa SDL_strtoull
+ */
+extern SDL_DECLSPEC double SDLCALL SDL_strtod(const char *str, char **endp);
+/**
+ * Compare two null-terminated UTF-8 strings.
+ *
+ * Due to the nature of UTF-8 encoding, this will work with Unicode strings,
+ * since effectively this function just compares bytes until it hits a
+ * null-terminating character. Also due to the nature of UTF-8, this can be
+ * used with SDL_qsort() to put strings in (roughly) alphabetical order.
+ *
+ * \param str1 the first string to compare. NULL is not permitted!
+ * \param str2 the second string to compare. NULL is not permitted!
+ * \returns less than zero if str1 is "less than" str2, greater than zero if
+ *          str1 is "greater than" str2, and zero if the strings match
+ *          exactly.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_strcmp(const char *str1, const char *str2);
+/**
+ * Compare two UTF-8 strings up to a number of bytes.
+ *
+ * Due to the nature of UTF-8 encoding, this will work with Unicode strings,
+ * since effectively this function just compares bytes until it hits a
+ * null-terminating character. Also due to the nature of UTF-8, this can be
+ * used with SDL_qsort() to put strings in (roughly) alphabetical order.
+ *
+ * Note that while this function is intended to be used with UTF-8, it is
+ * doing a bytewise comparison, and `maxlen` specifies a _byte_ limit! If the
+ * limit lands in the middle of a multi-byte UTF-8 sequence, it will only
+ * compare a portion of the final character.
+ *
+ * `maxlen` specifies a maximum number of bytes to compare; if the strings
+ * match to this number of bytes (or both have matched to a null-terminator
+ * character before this number of bytes), they will be considered equal.
+ *
+ * \param str1 the first string to compare. NULL is not permitted!
+ * \param str2 the second string to compare. NULL is not permitted!
+ * \param maxlen the maximum number of _bytes_ to compare.
+ * \returns less than zero if str1 is "less than" str2, greater than zero if
+ *          str1 is "greater than" str2, and zero if the strings match
+ *          exactly.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_strncmp(const char *str1, const char *str2, size_t maxlen);
+/**
+ * Compare two null-terminated UTF-8 strings, case-insensitively.
+ *
+ * This will work with Unicode strings, using a technique called
+ * "case-folding" to handle the vast majority of case-sensitive human
+ * languages regardless of system locale. It can deal with expanding values: a
+ * German Eszett character can compare against two ASCII 's' chars and be
+ * considered a match, for example. A notable exception: it does not handle
+ * the Turkish 'i' character; human language is complicated!
+ *
+ * Since this handles Unicode, it expects the string to be well-formed UTF-8
+ * and not a null-terminated string of arbitrary bytes. Bytes that are not
+ * valid UTF-8 are treated as Unicode character U+FFFD (REPLACEMENT
+ * CHARACTER), which is to say two strings of random bits may turn out to
+ * match if they convert to the same amount of replacement characters.
+ *
+ * \param str1 the first string to compare. NULL is not permitted!
+ * \param str2 the second string to compare. NULL is not permitted!
+ * \returns less than zero if str1 is "less than" str2, greater than zero if
+ *          str1 is "greater than" str2, and zero if the strings match
+ *          exactly.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_strcasecmp(const char *str1, const char *str2);
+/**
+ * Compare two UTF-8 strings, case-insensitively, up to a number of bytes.
+ *
+ * This will work with Unicode strings, using a technique called
+ * "case-folding" to handle the vast majority of case-sensitive human
+ * languages regardless of system locale. It can deal with expanding values: a
+ * German Eszett character can compare against two ASCII 's' chars and be
+ * considered a match, for example. A notable exception: it does not handle
+ * the Turkish 'i' character; human language is complicated!
+ *
+ * Since this handles Unicode, it expects the string to be well-formed UTF-8
+ * and not a null-terminated string of arbitrary bytes. Bytes that are not
+ * valid UTF-8 are treated as Unicode character U+FFFD (REPLACEMENT
+ * CHARACTER), which is to say two strings of random bits may turn out to
+ * match if they convert to the same amount of replacement characters.
+ *
+ * Note that while this function is intended to be used with UTF-8, `maxlen`
+ * specifies a _byte_ limit! If the limit lands in the middle of a multi-byte
+ * UTF-8 sequence, it may convert a portion of the final character to one or
+ * more Unicode character U+FFFD (REPLACEMENT CHARACTER) so as not to overflow
+ * a buffer.
+ *
+ * `maxlen` specifies a maximum number of bytes to compare; if the strings
+ * match to this number of bytes (or both have matched to a null-terminator
+ * character before this number of bytes), they will be considered equal.
+ *
+ * \param str1 the first string to compare. NULL is not permitted!
+ * \param str2 the second string to compare. NULL is not permitted!
+ * \param maxlen the maximum number of bytes to compare.
+ * \returns less than zero if str1 is "less than" str2, greater than zero if
+ *          str1 is "greater than" str2, and zero if the strings match
+ *          exactly.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_strncasecmp(const char *str1, const char *str2, size_t maxlen);
+/**
+ * Searches a string for the first occurence of any character contained in a
+ * breakset, and returns a pointer from the string to that character.
+ *
+ * \param str The null-terminated string to be searched. Must not be NULL, and
+ *            must not overlap with `breakset`.
+ * \param breakset A null-terminated string containing the list of characters
+ *                 to look for. Must not be NULL, and must not overlap with
+ *                 `str`.
+ * \returns A pointer to the location, in str, of the first occurence of a
+ *          character present in the breakset, or NULL if none is found.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC char * SDLCALL SDL_strpbrk(const char *str, const char *breakset);
+/**
+ * The Unicode REPLACEMENT CHARACTER codepoint.
+ *
+ * SDL_StepUTF8() and SDL_StepBackUTF8() report this codepoint when they
+ * encounter a UTF-8 string with encoding errors.
+ *
+ * This tends to render as something like a question mark in most places.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ *
+ * \sa SDL_StepBackUTF8
+ * \sa SDL_StepUTF8
+ */
+#define SDL_INVALID_UNICODE_CODEPOINT 0xFFFD
+/**
+ * Decode a UTF-8 string, one Unicode codepoint at a time.
+ *
+ * This will return the first Unicode codepoint in the UTF-8 encoded string in
+ * `*pstr`, and then advance `*pstr` past any consumed bytes before returning.
+ *
+ * It will not access more than `*pslen` bytes from the string. `*pslen` will
+ * be adjusted, as well, subtracting the number of bytes consumed.
+ *
+ * `pslen` is allowed to be NULL, in which case the string _must_ be
+ * NULL-terminated, as the function will blindly read until it sees the NULL
+ * char.
+ *
+ * if `*pslen` is zero, it assumes the end of string is reached and returns a
+ * zero codepoint regardless of the contents of the string buffer.
+ *
+ * If the resulting codepoint is zero (a NULL terminator), or `*pslen` is
+ * zero, it will not advance `*pstr` or `*pslen` at all.
+ *
+ * Generally this function is called in a loop until it returns zero,
+ * adjusting its parameters each iteration.
+ *
+ * If an invalid UTF-8 sequence is encountered, this function returns
+ * SDL_INVALID_UNICODE_CODEPOINT and advances the string/length by one byte
+ * (which is to say, a multibyte sequence might produce several
+ * SDL_INVALID_UNICODE_CODEPOINT returns before it syncs to the next valid
+ * UTF-8 sequence).
+ *
+ * Several things can generate invalid UTF-8 sequences, including overlong
+ * encodings, the use of UTF-16 surrogate values, and truncated data. Please
+ * refer to
+ * [RFC3629](https://www.ietf.org/rfc/rfc3629.txt)
+ * for details.
+ *
+ * \param pstr a pointer to a UTF-8 string pointer to be read and adjusted.
+ * \param pslen a pointer to the number of bytes in the string, to be read and
+ *              adjusted. NULL is allowed.
+ * \returns the first Unicode codepoint in the string.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC Uint32 SDLCALL SDL_StepUTF8(const char **pstr, size_t *pslen);
+/**
+ * Decode a UTF-8 string in reverse, one Unicode codepoint at a time.
+ *
+ * This will go to the start of the previous Unicode codepoint in the string,
+ * move `*pstr` to that location and return that codepoint.
+ *
+ * If `*pstr` is already at the start of the string), it will not advance
+ * `*pstr` at all.
+ *
+ * Generally this function is called in a loop until it returns zero,
+ * adjusting its parameter each iteration.
+ *
+ * If an invalid UTF-8 sequence is encountered, this function returns
+ * SDL_INVALID_UNICODE_CODEPOINT.
+ *
+ * Several things can generate invalid UTF-8 sequences, including overlong
+ * encodings, the use of UTF-16 surrogate values, and truncated data. Please
+ * refer to
+ * [RFC3629](https://www.ietf.org/rfc/rfc3629.txt)
+ * for details.
+ *
+ * \param start a pointer to the beginning of the UTF-8 string.
+ * \param pstr a pointer to a UTF-8 string pointer to be read and adjusted.
+ * \returns the previous Unicode codepoint in the string.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC Uint32 SDLCALL SDL_StepBackUTF8(const char *start, const char **pstr);
+/**
+ * Convert a single Unicode codepoint to UTF-8.
+ *
+ * The buffer pointed to by `dst` must be at least 4 bytes long, as this
+ * function may generate between 1 and 4 bytes of output.
+ *
+ * This function returns the first byte _after_ the newly-written UTF-8
+ * sequence, which is useful for encoding multiple codepoints in a loop, or
+ * knowing where to write a NULL-terminator character to end the string (in
+ * either case, plan to have a buffer of _more_ than 4 bytes!).
+ *
+ * If `codepoint` is an invalid value (outside the Unicode range, or a UTF-16
+ * surrogate value, etc), this will use U+FFFD (REPLACEMENT CHARACTER) for the
+ * codepoint instead, and not set an error.
+ *
+ * If `dst` is NULL, this returns NULL immediately without writing to the
+ * pointer and without setting an error.
+ *
+ * \param codepoint a Unicode codepoint to convert to UTF-8.
+ * \param dst the location to write the encoded UTF-8. Must point to at least
+ *            4 bytes!
+ * \returns the first byte past the newly-written UTF-8 sequence.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC char * SDLCALL SDL_UCS4ToUTF8(Uint32 codepoint, char *dst);
+/**
+ * This works exactly like sscanf() but doesn't require access to a C runtime.
+ *
+ * Scan a string, matching a format string, converting each '%' item and
+ * storing it to pointers provided through variable arguments.
+ *
+ * \param text the string to scan. Must not be NULL.
+ * \param fmt a printf-style format string. Must not be NULL.
+ * \param ... a list of pointers to values to be filled in with scanned items.
+ * \returns the number of items that matched the format string.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_sscanf(const char *text, SDL_SCANF_FORMAT_STRING const char *fmt, ...) SDL_SCANF_VARARG_FUNC(2);
+/**
+ * This works exactly like vsscanf() but doesn't require access to a C
+ * runtime.
+ *
+ * Functions identically to SDL_sscanf(), except it takes a `va_list` instead
+ * of using `...` variable arguments.
+ *
+ * \param text the string to scan. Must not be NULL.
+ * \param fmt a printf-style format string. Must not be NULL.
+ * \param ap a `va_list` of pointers to values to be filled in with scanned
+ *           items.
+ * \returns the number of items that matched the format string.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_vsscanf(const char *text, SDL_SCANF_FORMAT_STRING const char *fmt, va_list ap) SDL_SCANF_VARARG_FUNCV(2);
+/**
+ * This works exactly like snprintf() but doesn't require access to a C
+ * runtime.
+ *
+ * Format a string of up to `maxlen`-1 bytes, converting each '%' item with
+ * values provided through variable arguments.
+ *
+ * While some C runtimes differ on how to deal with too-large strings, this
+ * function null-terminates the output, by treating the null-terminator as
+ * part of the `maxlen` count. Note that if `maxlen` is zero, however, no
+ * bytes will be written at all.
+ *
+ * This function returns the number of _bytes_ (not _characters_) that should
+ * be written, excluding the null-terminator character. If this returns a
+ * number >= `maxlen`, it means the output string was truncated. A negative
+ * return value means an error occurred.
+ *
+ * Referencing the output string's pointer with a format item is undefined
+ * behavior.
+ *
+ * \param text the buffer to write the string into. Must not be NULL.
+ * \param maxlen the maximum bytes to write, including the null-terminator.
+ * \param fmt a printf-style format string. Must not be NULL.
+ * \param ... a list of values to be used with the format string.
+ * \returns the number of bytes that should be written, not counting the
+ *          null-terminator char, or a negative value on error.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_snprintf(SDL_OUT_Z_CAP(maxlen) char *text, size_t maxlen, SDL_PRINTF_FORMAT_STRING const char *fmt, ...) SDL_PRINTF_VARARG_FUNC(3);
+/**
+ * This works exactly like swprintf() but doesn't require access to a C
+ * runtime.
+ *
+ * Format a wide string of up to `maxlen`-1 wchar_t values, converting each
+ * '%' item with values provided through variable arguments.
+ *
+ * While some C runtimes differ on how to deal with too-large strings, this
+ * function null-terminates the output, by treating the null-terminator as
+ * part of the `maxlen` count. Note that if `maxlen` is zero, however, no wide
+ * characters will be written at all.
+ *
+ * This function returns the number of _wide characters_ (not _codepoints_)
+ * that should be written, excluding the null-terminator character. If this
+ * returns a number >= `maxlen`, it means the output string was truncated. A
+ * negative return value means an error occurred.
+ *
+ * Referencing the output string's pointer with a format item is undefined
+ * behavior.
+ *
+ * \param text the buffer to write the wide string into. Must not be NULL.
+ * \param maxlen the maximum wchar_t values to write, including the
+ *               null-terminator.
+ * \param fmt a printf-style format string. Must not be NULL.
+ * \param ... a list of values to be used with the format string.
+ * \returns the number of wide characters that should be written, not counting
+ *          the null-terminator char, or a negative value on error.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_swprintf(SDL_OUT_Z_CAP(maxlen) wchar_t *text, size_t maxlen, SDL_PRINTF_FORMAT_STRING const wchar_t *fmt, ...) SDL_WPRINTF_VARARG_FUNC(3);
+/**
+ * This works exactly like vsnprintf() but doesn't require access to a C
+ * runtime.
+ *
+ * Functions identically to SDL_snprintf(), except it takes a `va_list`
+ * instead of using `...` variable arguments.
+ *
+ * \param text the buffer to write the string into. Must not be NULL.
+ * \param maxlen the maximum bytes to write, including the null-terminator.
+ * \param fmt a printf-style format string. Must not be NULL.
+ * \param ap a `va_list` values to be used with the format string.
+ * \returns the number of bytes that should be written, not counting the
+ *          null-terminator char, or a negative value on error.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_vsnprintf(SDL_OUT_Z_CAP(maxlen) char *text, size_t maxlen, SDL_PRINTF_FORMAT_STRING const char *fmt, va_list ap) SDL_PRINTF_VARARG_FUNCV(3);
+/**
+ * This works exactly like vswprintf() but doesn't require access to a C
+ * runtime.
+ *
+ * Functions identically to SDL_swprintf(), except it takes a `va_list`
+ * instead of using `...` variable arguments.
+ *
+ * \param text the buffer to write the string into. Must not be NULL.
+ * \param maxlen the maximum wide characters to write, including the
+ *               null-terminator.
+ * \param fmt a printf-style format wide string. Must not be NULL.
+ * \param ap a `va_list` values to be used with the format string.
+ * \returns the number of wide characters that should be written, not counting
+ *          the null-terminator char, or a negative value on error.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_vswprintf(SDL_OUT_Z_CAP(maxlen) wchar_t *text, size_t maxlen, SDL_PRINTF_FORMAT_STRING const wchar_t *fmt, va_list ap) SDL_WPRINTF_VARARG_FUNCV(3);
+/**
+ * This works exactly like asprintf() but doesn't require access to a C
+ * runtime.
+ *
+ * Functions identically to SDL_snprintf(), except it allocates a buffer large
+ * enough to hold the output string on behalf of the caller.
+ *
+ * On success, this function returns the number of bytes (not characters)
+ * comprising the output string, not counting the null-terminator character,
+ * and sets `*strp` to the newly-allocated string.
+ *
+ * On error, this function returns a negative number, and the value of `*strp`
+ * is undefined.
+ *
+ * The returned string is owned by the caller, and should be passed to
+ * SDL_free when no longer needed.
+ *
+ * \param strp on output, is set to the new string. Must not be NULL.
+ * \param fmt a printf-style format string. Must not be NULL.
+ * \param ... a list of values to be used with the format string.
+ * \returns the number of bytes in the newly-allocated string, not counting
+ *          the null-terminator char, or a negative value on error.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_asprintf(char **strp, SDL_PRINTF_FORMAT_STRING const char *fmt, ...) SDL_PRINTF_VARARG_FUNC(2);
+/**
+ * This works exactly like vasprintf() but doesn't require access to a C
+ * runtime.
+ *
+ * Functions identically to SDL_asprintf(), except it takes a `va_list`
+ * instead of using `...` variable arguments.
+ *
+ * \param strp on output, is set to the new string. Must not be NULL.
+ * \param fmt a printf-style format string. Must not be NULL.
+ * \param ap a `va_list` values to be used with the format string.
+ * \returns the number of bytes in the newly-allocated string, not counting
+ *          the null-terminator char, or a negative value on error.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_vasprintf(char **strp, SDL_PRINTF_FORMAT_STRING const char *fmt, va_list ap) SDL_PRINTF_VARARG_FUNCV(2);
+/**
+ * Seeds the pseudo-random number generator.
+ *
+ * Reusing the seed number will cause SDL_rand() to repeat the same stream of
+ * 'random' numbers.
+ *
+ * \param seed the value to use as a random number seed, or 0 to use
+ *             SDL_GetPerformanceCounter().
+ *
+ * \threadsafety This should be called on the same thread that calls
+ *               SDL_rand()
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_rand
+ * \sa SDL_rand_bits
+ * \sa SDL_randf
+ */
+extern SDL_DECLSPEC void SDLCALL SDL_srand(Uint64 seed);
+/**
+ * Generate a pseudo-random number less than n for positive n
+ *
+ * The method used is faster and of better quality than `rand() % n`. Odds are
+ * roughly 99.9% even for n = 1 million. Evenness is better for smaller n, and
+ * much worse as n gets bigger.
+ *
+ * Example: to simulate a d6 use `SDL_rand(6) + 1` The +1 converts 0..5 to
+ * 1..6
+ *
+ * If you want to generate a pseudo-random number in the full range of Sint32,
+ * you should use: (Sint32)SDL_rand_bits()
+ *
+ * If you want reproducible output, be sure to initialize with SDL_srand()
+ * first.
+ *
+ * There are no guarantees as to the quality of the random sequence produced,
+ * and this should not be used for security (cryptography, passwords) or where
+ * money is on the line (loot-boxes, casinos). There are many random number
+ * libraries available with different characteristics and you should pick one
+ * of those to meet any serious needs.
+ *
+ * \param n the number of possible outcomes. n must be positive.
+ * \returns a random value in the range of [0 .. n-1].
+ *
+ * \threadsafety All calls should be made from a single thread
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_srand
+ * \sa SDL_randf
+ */
+extern SDL_DECLSPEC Sint32 SDLCALL SDL_rand(Sint32 n);
+/**
+ * Generate a uniform pseudo-random floating point number less than 1.0
+ *
+ * If you want reproducible output, be sure to initialize with SDL_srand()
+ * first.
+ *
+ * There are no guarantees as to the quality of the random sequence produced,
+ * and this should not be used for security (cryptography, passwords) or where
+ * money is on the line (loot-boxes, casinos). There are many random number
+ * libraries available with different characteristics and you should pick one
+ * of those to meet any serious needs.
+ *
+ * \returns a random value in the range of [0.0, 1.0).
+ *
+ * \threadsafety All calls should be made from a single thread
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_srand
+ * \sa SDL_rand
+ */
+extern SDL_DECLSPEC float SDLCALL SDL_randf(void);
+/**
+ * Generate 32 pseudo-random bits.
+ *
+ * You likely want to use SDL_rand() to get a psuedo-random number instead.
+ *
+ * There are no guarantees as to the quality of the random sequence produced,
+ * and this should not be used for security (cryptography, passwords) or where
+ * money is on the line (loot-boxes, casinos). There are many random number
+ * libraries available with different characteristics and you should pick one
+ * of those to meet any serious needs.
+ *
+ * \returns a random value in the range of [0-SDL_MAX_UINT32].
+ *
+ * \threadsafety All calls should be made from a single thread
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_rand
+ * \sa SDL_randf
+ * \sa SDL_srand
+ */
+extern SDL_DECLSPEC Uint32 SDLCALL SDL_rand_bits(void);
+/**
+ * Generate a pseudo-random number less than n for positive n
+ *
+ * The method used is faster and of better quality than `rand() % n`. Odds are
+ * roughly 99.9% even for n = 1 million. Evenness is better for smaller n, and
+ * much worse as n gets bigger.
+ *
+ * Example: to simulate a d6 use `SDL_rand_r(state, 6) + 1` The +1 converts
+ * 0..5 to 1..6
+ *
+ * If you want to generate a pseudo-random number in the full range of Sint32,
+ * you should use: (Sint32)SDL_rand_bits_r(state)
+ *
+ * There are no guarantees as to the quality of the random sequence produced,
+ * and this should not be used for security (cryptography, passwords) or where
+ * money is on the line (loot-boxes, casinos). There are many random number
+ * libraries available with different characteristics and you should pick one
+ * of those to meet any serious needs.
+ *
+ * \param state a pointer to the current random number state, this may not be
+ *              NULL.
+ * \param n the number of possible outcomes. n must be positive.
+ * \returns a random value in the range of [0 .. n-1].
+ *
+ * \threadsafety This function is thread-safe, as long as the state pointer
+ *               isn't shared between threads.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_rand
+ * \sa SDL_rand_bits_r
+ * \sa SDL_randf_r
+ */
+extern SDL_DECLSPEC Sint32 SDLCALL SDL_rand_r(Uint64 *state, Sint32 n);
+/**
+ * Generate a uniform pseudo-random floating point number less than 1.0
+ *
+ * If you want reproducible output, be sure to initialize with SDL_srand()
+ * first.
+ *
+ * There are no guarantees as to the quality of the random sequence produced,
+ * and this should not be used for security (cryptography, passwords) or where
+ * money is on the line (loot-boxes, casinos). There are many random number
+ * libraries available with different characteristics and you should pick one
+ * of those to meet any serious needs.
+ *
+ * \param state a pointer to the current random number state, this may not be
+ *              NULL.
+ * \returns a random value in the range of [0.0, 1.0).
+ *
+ * \threadsafety This function is thread-safe, as long as the state pointer
+ *               isn't shared between threads.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_rand_bits_r
+ * \sa SDL_rand_r
+ * \sa SDL_randf
+ */
+extern SDL_DECLSPEC float SDLCALL SDL_randf_r(Uint64 *state);
+/**
+ * Generate 32 pseudo-random bits.
+ *
+ * You likely want to use SDL_rand_r() to get a psuedo-random number instead.
+ *
+ * There are no guarantees as to the quality of the random sequence produced,
+ * and this should not be used for security (cryptography, passwords) or where
+ * money is on the line (loot-boxes, casinos). There are many random number
+ * libraries available with different characteristics and you should pick one
+ * of those to meet any serious needs.
+ *
+ * \param state a pointer to the current random number state, this may not be
+ *              NULL.
+ * \returns a random value in the range of [0-SDL_MAX_UINT32].
+ *
+ * \threadsafety This function is thread-safe, as long as the state pointer
+ *               isn't shared between threads.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_rand_r
+ * \sa SDL_randf_r
+ */
+extern SDL_DECLSPEC Uint32 SDLCALL SDL_rand_bits_r(Uint64 *state);
+#ifndef SDL_PI_D
+/**
+ * The value of Pi, as a double-precision floating point literal.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ *
+ * \sa SDL_PI_F
+ */
+#define SDL_PI_D   3.141592653589793238462643383279502884       /**< pi (double) */
+#endif
+#ifndef SDL_PI_F
+/**
+ * The value of Pi, as a single-precision floating point literal.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ *
+ * \sa SDL_PI_D
+ */
+#define SDL_PI_F   3.141592653589793238462643383279502884F      /**< pi (float) */
+#endif
+/**
+ * Compute the arc cosine of `x`.
+ *
+ * The definition of `y = acos(x)` is `x = cos(y)`.
+ *
+ * Domain: `-1 <= x <= 1`
+ *
+ * Range: `0 <= y <= Pi`
+ *
+ * This function operates on double-precision floating point values, use
+ * SDL_acosf for single-precision floats.
+ *
+ * This function may use a different approximation across different versions,
+ * platforms and configurations. i.e, it can return a different value given
+ * the same input on different machines or operating systems, or if SDL is
+ * updated.
+ *
+ * \param x floating point value.
+ * \returns arc cosine of `x`, in radians.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_acosf
+ * \sa SDL_asin
+ * \sa SDL_cos
+ */
+extern SDL_DECLSPEC double SDLCALL SDL_acos(double x);
+/**
+ * Compute the arc cosine of `x`.
+ *
+ * The definition of `y = acos(x)` is `x = cos(y)`.
+ *
+ * Domain: `-1 <= x <= 1`
+ *
+ * Range: `0 <= y <= Pi`
+ *
+ * This function operates on single-precision floating point values, use
+ * SDL_acos for double-precision floats.
+ *
+ * This function may use a different approximation across different versions,
+ * platforms and configurations. i.e, it can return a different value given
+ * the same input on different machines or operating systems, or if SDL is
+ * updated.
+ *
+ * \param x floating point value.
+ * \returns arc cosine of `x`, in radians.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_acos
+ * \sa SDL_asinf
+ * \sa SDL_cosf
+ */
+extern SDL_DECLSPEC float SDLCALL SDL_acosf(float x);
+/**
+ * Compute the arc sine of `x`.
+ *
+ * The definition of `y = asin(x)` is `x = sin(y)`.
+ *
+ * Domain: `-1 <= x <= 1`
+ *
+ * Range: `-Pi/2 <= y <= Pi/2`
+ *
+ * This function operates on double-precision floating point values, use
+ * SDL_asinf for single-precision floats.
+ *
+ * This function may use a different approximation across different versions,
+ * platforms and configurations. i.e, it can return a different value given
+ * the same input on different machines or operating systems, or if SDL is
+ * updated.
+ *
+ * \param x floating point value.
+ * \returns arc sine of `x`, in radians.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_asinf
+ * \sa SDL_acos
+ * \sa SDL_sin
+ */
+extern SDL_DECLSPEC double SDLCALL SDL_asin(double x);
+/**
+ * Compute the arc sine of `x`.
+ *
+ * The definition of `y = asin(x)` is `x = sin(y)`.
+ *
+ * Domain: `-1 <= x <= 1`
+ *
+ * Range: `-Pi/2 <= y <= Pi/2`
+ *
+ * This function operates on single-precision floating point values, use
+ * SDL_asin for double-precision floats.
+ *
+ * This function may use a different approximation across different versions,
+ * platforms and configurations. i.e, it can return a different value given
+ * the same input on different machines or operating systems, or if SDL is
+ * updated.
+ *
+ * \param x floating point value.
+ * \returns arc sine of `x`, in radians.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_asin
+ * \sa SDL_acosf
+ * \sa SDL_sinf
+ */
+extern SDL_DECLSPEC float SDLCALL SDL_asinf(float x);
+/**
+ * Compute the arc tangent of `x`.
+ *
+ * The definition of `y = atan(x)` is `x = tan(y)`.
+ *
+ * Domain: `-INF <= x <= INF`
+ *
+ * Range: `-Pi/2 <= y <= Pi/2`
+ *
+ * This function operates on double-precision floating point values, use
+ * SDL_atanf for single-precision floats.
+ *
+ * To calculate the arc tangent of y / x, use SDL_atan2.
+ *
+ * This function may use a different approximation across different versions,
+ * platforms and configurations. i.e, it can return a different value given
+ * the same input on different machines or operating systems, or if SDL is
+ * updated.
+ *
+ * \param x floating point value.
+ * \returns arc tangent of of `x` in radians, or 0 if `x = 0`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_atanf
+ * \sa SDL_atan2
+ * \sa SDL_tan
+ */
+extern SDL_DECLSPEC double SDLCALL SDL_atan(double x);
+/**
+ * Compute the arc tangent of `x`.
+ *
+ * The definition of `y = atan(x)` is `x = tan(y)`.
+ *
+ * Domain: `-INF <= x <= INF`
+ *
+ * Range: `-Pi/2 <= y <= Pi/2`
+ *
+ * This function operates on single-precision floating point values, use
+ * SDL_atan for dboule-precision floats.
+ *
+ * To calculate the arc tangent of y / x, use SDL_atan2f.
+ *
+ * This function may use a different approximation across different versions,
+ * platforms and configurations. i.e, it can return a different value given
+ * the same input on different machines or operating systems, or if SDL is
+ * updated.
+ *
+ * \param x floating point value.
+ * \returns arc tangent of of `x` in radians, or 0 if `x = 0`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_atan
+ * \sa SDL_atan2f
+ * \sa SDL_tanf
+ */
+extern SDL_DECLSPEC float SDLCALL SDL_atanf(float x);
+/**
+ * Compute the arc tangent of `y / x`, using the signs of x and y to adjust
+ * the result's quadrant.
+ *
+ * The definition of `z = atan2(x, y)` is `y = x tan(z)`, where the quadrant
+ * of z is determined based on the signs of x and y.
+ *
+ * Domain: `-INF <= x <= INF`, `-INF <= y <= INF`
+ *
+ * Range: `-Pi/2 <= y <= Pi/2`
+ *
+ * This function operates on double-precision floating point values, use
+ * SDL_atan2f for single-precision floats.
+ *
+ * To calculate the arc tangent of a single value, use SDL_atan.
+ *
+ * This function may use a different approximation across different versions,
+ * platforms and configurations. i.e, it can return a different value given
+ * the same input on different machines or operating systems, or if SDL is
+ * updated.
+ *
+ * \param y floating point value of the numerator (y coordinate).
+ * \param x floating point value of the denominator (x coordinate).
+ * \returns arc tangent of of `y / x` in radians, or, if `x = 0`, either
+ *          `-Pi/2`, `0`, or `Pi/2`, depending on the value of `y`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_atan2f
+ * \sa SDL_atan
+ * \sa SDL_tan
+ */
+extern SDL_DECLSPEC double SDLCALL SDL_atan2(double y, double x);
+/**
+ * Compute the arc tangent of `y / x`, using the signs of x and y to adjust
+ * the result's quadrant.
+ *
+ * The definition of `z = atan2(x, y)` is `y = x tan(z)`, where the quadrant
+ * of z is determined based on the signs of x and y.
+ *
+ * Domain: `-INF <= x <= INF`, `-INF <= y <= INF`
+ *
+ * Range: `-Pi/2 <= y <= Pi/2`
+ *
+ * This function operates on single-precision floating point values, use
+ * SDL_atan2 for double-precision floats.
+ *
+ * To calculate the arc tangent of a single value, use SDL_atanf.
+ *
+ * This function may use a different approximation across different versions,
+ * platforms and configurations. i.e, it can return a different value given
+ * the same input on different machines or operating systems, or if SDL is
+ * updated.
+ *
+ * \param y floating point value of the numerator (y coordinate).
+ * \param x floating point value of the denominator (x coordinate).
+ * \returns arc tangent of of `y / x` in radians, or, if `x = 0`, either
+ *          `-Pi/2`, `0`, or `Pi/2`, depending on the value of `y`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_atan2
+ * \sa SDL_atan
+ * \sa SDL_tan
+ */
+extern SDL_DECLSPEC float SDLCALL SDL_atan2f(float y, float x);
+/**
+ * Compute the ceiling of `x`.
+ *
+ * The ceiling of `x` is the smallest integer `y` such that `y > x`, i.e `x`
+ * rounded up to the nearest integer.
+ *
+ * Domain: `-INF <= x <= INF`
+ *
+ * Range: `-INF <= y <= INF`, y integer
+ *
+ * This function operates on double-precision floating point values, use
+ * SDL_ceilf for single-precision floats.
+ *
+ * \param x floating point value.
+ * \returns the ceiling of `x`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_ceilf
+ * \sa SDL_floor
+ * \sa SDL_trunc
+ * \sa SDL_round
+ * \sa SDL_lround
+ */
+extern SDL_DECLSPEC double SDLCALL SDL_ceil(double x);
+/**
+ * Compute the ceiling of `x`.
+ *
+ * The ceiling of `x` is the smallest integer `y` such that `y > x`, i.e `x`
+ * rounded up to the nearest integer.
+ *
+ * Domain: `-INF <= x <= INF`
+ *
+ * Range: `-INF <= y <= INF`, y integer
+ *
+ * This function operates on single-precision floating point values, use
+ * SDL_ceil for double-precision floats.
+ *
+ * \param x floating point value.
+ * \returns the ceiling of `x`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_ceil
+ * \sa SDL_floorf
+ * \sa SDL_truncf
+ * \sa SDL_roundf
+ * \sa SDL_lroundf
+ */
+extern SDL_DECLSPEC float SDLCALL SDL_ceilf(float x);
+/**
+ * Copy the sign of one floating-point value to another.
+ *
+ * The definition of copysign is that ``copysign(x, y) = abs(x) * sign(y)``.
+ *
+ * Domain: `-INF <= x <= INF`, ``-INF <= y <= f``
+ *
+ * Range: `-INF <= z <= INF`
+ *
+ * This function operates on double-precision floating point values, use
+ * SDL_copysignf for single-precision floats.
+ *
+ * \param x floating point value to use as the magnitude.
+ * \param y floating point value to use as the sign.
+ * \returns the floating point value with the sign of y and the magnitude of
+ *          x.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_copysignf
+ * \sa SDL_fabs
+ */
+extern SDL_DECLSPEC double SDLCALL SDL_copysign(double x, double y);
+/**
+ * Copy the sign of one floating-point value to another.
+ *
+ * The definition of copysign is that ``copysign(x, y) = abs(x) * sign(y)``.
+ *
+ * Domain: `-INF <= x <= INF`, ``-INF <= y <= f``
+ *
+ * Range: `-INF <= z <= INF`
+ *
+ * This function operates on single-precision floating point values, use
+ * SDL_copysign for double-precision floats.
+ *
+ * \param x floating point value to use as the magnitude.
+ * \param y floating point value to use as the sign.
+ * \returns the floating point value with the sign of y and the magnitude of
+ *          x.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_copysign
+ * \sa SDL_fabsf
+ */
+extern SDL_DECLSPEC float SDLCALL SDL_copysignf(float x, float y);
+/**
+ * Compute the cosine of `x`.
+ *
+ * Domain: `-INF <= x <= INF`
+ *
+ * Range: `-1 <= y <= 1`
+ *
+ * This function operates on double-precision floating point values, use
+ * SDL_cosf for single-precision floats.
+ *
+ * This function may use a different approximation across different versions,
+ * platforms and configurations. i.e, it can return a different value given
+ * the same input on different machines or operating systems, or if SDL is
+ * updated.
+ *
+ * \param x floating point value, in radians.
+ * \returns cosine of `x`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_cosf
+ * \sa SDL_acos
+ * \sa SDL_sin
+ */
+extern SDL_DECLSPEC double SDLCALL SDL_cos(double x);
+/**
+ * Compute the cosine of `x`.
+ *
+ * Domain: `-INF <= x <= INF`
+ *
+ * Range: `-1 <= y <= 1`
+ *
+ * This function operates on single-precision floating point values, use
+ * SDL_cos for double-precision floats.
+ *
+ * This function may use a different approximation across different versions,
+ * platforms and configurations. i.e, it can return a different value given
+ * the same input on different machines or operating systems, or if SDL is
+ * updated.
+ *
+ * \param x floating point value, in radians.
+ * \returns cosine of `x`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_cos
+ * \sa SDL_acosf
+ * \sa SDL_sinf
+ */
+extern SDL_DECLSPEC float SDLCALL SDL_cosf(float x);
+/**
+ * Compute the exponential of `x`.
+ *
+ * The definition of `y = exp(x)` is `y = e^x`, where `e` is the base of the
+ * natural logarithm. The inverse is the natural logarithm, SDL_log.
+ *
+ * Domain: `-INF <= x <= INF`
+ *
+ * Range: `0 <= y <= INF`
+ *
+ * The output will overflow if `exp(x)` is too large to be represented.
+ *
+ * This function operates on double-precision floating point values, use
+ * SDL_expf for single-precision floats.
+ *
+ * This function may use a different approximation across different versions,
+ * platforms and configurations. i.e, it can return a different value given
+ * the same input on different machines or operating systems, or if SDL is
+ * updated.
+ *
+ * \param x floating point value.
+ * \returns value of `e^x`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_expf
+ * \sa SDL_log
+ */
+extern SDL_DECLSPEC double SDLCALL SDL_exp(double x);
+/**
+ * Compute the exponential of `x`.
+ *
+ * The definition of `y = exp(x)` is `y = e^x`, where `e` is the base of the
+ * natural logarithm. The inverse is the natural logarithm, SDL_logf.
+ *
+ * Domain: `-INF <= x <= INF`
+ *
+ * Range: `0 <= y <= INF`
+ *
+ * The output will overflow if `exp(x)` is too large to be represented.
+ *
+ * This function operates on single-precision floating point values, use
+ * SDL_exp for double-precision floats.
+ *
+ * This function may use a different approximation across different versions,
+ * platforms and configurations. i.e, it can return a different value given
+ * the same input on different machines or operating systems, or if SDL is
+ * updated.
+ *
+ * \param x floating point value.
+ * \returns value of `e^x`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_exp
+ * \sa SDL_logf
+ */
+extern SDL_DECLSPEC float SDLCALL SDL_expf(float x);
+/**
+ * Compute the absolute value of `x`
+ *
+ * Domain: `-INF <= x <= INF`
+ *
+ * Range: `0 <= y <= INF`
+ *
+ * This function operates on double-precision floating point values, use
+ * SDL_fabsf for single-precision floats.
+ *
+ * \param x floating point value to use as the magnitude.
+ * \returns the absolute value of `x`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_fabsf
+ */
+extern SDL_DECLSPEC double SDLCALL SDL_fabs(double x);
+/**
+ * Compute the absolute value of `x`
+ *
+ * Domain: `-INF <= x <= INF`
+ *
+ * Range: `0 <= y <= INF`
+ *
+ * This function operates on single-precision floating point values, use
+ * SDL_fabs for double-precision floats.
+ *
+ * \param x floating point value to use as the magnitude.
+ * \returns the absolute value of `x`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_fabs
+ */
+extern SDL_DECLSPEC float SDLCALL SDL_fabsf(float x);
+/**
+ * Compute the floor of `x`.
+ *
+ * The floor of `x` is the largest integer `y` such that `y > x`, i.e `x`
+ * rounded down to the nearest integer.
+ *
+ * Domain: `-INF <= x <= INF`
+ *
+ * Range: `-INF <= y <= INF`, y integer
+ *
+ * This function operates on double-precision floating point values, use
+ * SDL_floorf for single-precision floats.
+ *
+ * \param x floating point value.
+ * \returns the floor of `x`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_floorf
+ * \sa SDL_ceil
+ * \sa SDL_trunc
+ * \sa SDL_round
+ * \sa SDL_lround
+ */
+extern SDL_DECLSPEC double SDLCALL SDL_floor(double x);
+/**
+ * Compute the floor of `x`.
+ *
+ * The floor of `x` is the largest integer `y` such that `y > x`, i.e `x`
+ * rounded down to the nearest integer.
+ *
+ * Domain: `-INF <= x <= INF`
+ *
+ * Range: `-INF <= y <= INF`, y integer
+ *
+ * This function operates on single-precision floating point values, use
+ * SDL_floor for double-precision floats.
+ *
+ * \param x floating point value.
+ * \returns the floor of `x`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_floor
+ * \sa SDL_ceilf
+ * \sa SDL_truncf
+ * \sa SDL_roundf
+ * \sa SDL_lroundf
+ */
+extern SDL_DECLSPEC float SDLCALL SDL_floorf(float x);
+/**
+ * Truncate `x` to an integer.
+ *
+ * Rounds `x` to the next closest integer to 0. This is equivalent to removing
+ * the fractional part of `x`, leaving only the integer part.
+ *
+ * Domain: `-INF <= x <= INF`
+ *
+ * Range: `-INF <= y <= INF`, y integer
+ *
+ * This function operates on double-precision floating point values, use
+ * SDL_truncf for single-precision floats.
+ *
+ * \param x floating point value.
+ * \returns `x` truncated to an integer.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_truncf
+ * \sa SDL_fmod
+ * \sa SDL_ceil
+ * \sa SDL_floor
+ * \sa SDL_round
+ * \sa SDL_lround
+ */
+extern SDL_DECLSPEC double SDLCALL SDL_trunc(double x);
+/**
+ * Truncate `x` to an integer.
+ *
+ * Rounds `x` to the next closest integer to 0. This is equivalent to removing
+ * the fractional part of `x`, leaving only the integer part.
+ *
+ * Domain: `-INF <= x <= INF`
+ *
+ * Range: `-INF <= y <= INF`, y integer
+ *
+ * This function operates on single-precision floating point values, use
+ * SDL_trunc for double-precision floats.
+ *
+ * \param x floating point value.
+ * \returns `x` truncated to an integer.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_trunc
+ * \sa SDL_fmodf
+ * \sa SDL_ceilf
+ * \sa SDL_floorf
+ * \sa SDL_roundf
+ * \sa SDL_lroundf
+ */
+extern SDL_DECLSPEC float SDLCALL SDL_truncf(float x);
+/**
+ * Return the floating-point remainder of `x / y`
+ *
+ * Divides `x` by `y`, and returns the remainder.
+ *
+ * Domain: `-INF <= x <= INF`, `-INF <= y <= INF`, `y != 0`
+ *
+ * Range: `-y <= z <= y`
+ *
+ * This function operates on double-precision floating point values, use
+ * SDL_fmodf for single-precision floats.
+ *
+ * \param x the numerator.
+ * \param y the denominator. Must not be 0.
+ * \returns the remainder of `x / y`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_fmodf
+ * \sa SDL_modf
+ * \sa SDL_trunc
+ * \sa SDL_ceil
+ * \sa SDL_floor
+ * \sa SDL_round
+ * \sa SDL_lround
+ */
+extern SDL_DECLSPEC double SDLCALL SDL_fmod(double x, double y);
+/**
+ * Return the floating-point remainder of `x / y`
+ *
+ * Divides `x` by `y`, and returns the remainder.
+ *
+ * Domain: `-INF <= x <= INF`, `-INF <= y <= INF`, `y != 0`
+ *
+ * Range: `-y <= z <= y`
+ *
+ * This function operates on single-precision floating point values, use
+ * SDL_fmod for double-precision floats.
+ *
+ * \param x the numerator.
+ * \param y the denominator. Must not be 0.
+ * \returns the remainder of `x / y`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_fmod
+ * \sa SDL_truncf
+ * \sa SDL_modff
+ * \sa SDL_ceilf
+ * \sa SDL_floorf
+ * \sa SDL_roundf
+ * \sa SDL_lroundf
+ */
+extern SDL_DECLSPEC float SDLCALL SDL_fmodf(float x, float y);
+/**
+ * Return whether the value is infinity.
+ *
+ * \param x double-precision floating point value.
+ * \returns non-zero if the value is infinity, 0 otherwise.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_isinff
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_isinf(double x);
+/**
+ * Return whether the value is infinity.
+ *
+ * \param x floating point value.
+ * \returns non-zero if the value is infinity, 0 otherwise.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_isinf
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_isinff(float x);
+/**
+ * Return whether the value is NaN.
+ *
+ * \param x double-precision floating point value.
+ * \returns non-zero if the value is NaN, 0 otherwise.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_isnanf
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_isnan(double x);
+/**
+ * Return whether the value is NaN.
+ *
+ * \param x floating point value.
+ * \returns non-zero if the value is NaN, 0 otherwise.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_isnan
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_isnanf(float x);
+/**
+ * Compute the natural logarithm of `x`.
+ *
+ * Domain: `0 < x <= INF`
+ *
+ * Range: `-INF <= y <= INF`
+ *
+ * It is an error for `x` to be less than or equal to 0.
+ *
+ * This function operates on double-precision floating point values, use
+ * SDL_logf for single-precision floats.
+ *
+ * This function may use a different approximation across different versions,
+ * platforms and configurations. i.e, it can return a different value given
+ * the same input on different machines or operating systems, or if SDL is
+ * updated.
+ *
+ * \param x floating point value. Must be greater than 0.
+ * \returns the natural logarithm of `x`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_logf
+ * \sa SDL_log10
+ * \sa SDL_exp
+ */
+extern SDL_DECLSPEC double SDLCALL SDL_log(double x);
+/**
+ * Compute the natural logarithm of `x`.
+ *
+ * Domain: `0 < x <= INF`
+ *
+ * Range: `-INF <= y <= INF`
+ *
+ * It is an error for `x` to be less than or equal to 0.
+ *
+ * This function operates on single-precision floating point values, use
+ * SDL_log for double-precision floats.
+ *
+ * This function may use a different approximation across different versions,
+ * platforms and configurations. i.e, it can return a different value given
+ * the same input on different machines or operating systems, or if SDL is
+ * updated.
+ *
+ * \param x floating point value. Must be greater than 0.
+ * \returns the natural logarithm of `x`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_log
+ * \sa SDL_expf
+ */
+extern SDL_DECLSPEC float SDLCALL SDL_logf(float x);
+/**
+ * Compute the base-10 logarithm of `x`.
+ *
+ * Domain: `0 < x <= INF`
+ *
+ * Range: `-INF <= y <= INF`
+ *
+ * It is an error for `x` to be less than or equal to 0.
+ *
+ * This function operates on double-precision floating point values, use
+ * SDL_log10f for single-precision floats.
+ *
+ * This function may use a different approximation across different versions,
+ * platforms and configurations. i.e, it can return a different value given
+ * the same input on different machines or operating systems, or if SDL is
+ * updated.
+ *
+ * \param x floating point value. Must be greater than 0.
+ * \returns the logarithm of `x`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_log10f
+ * \sa SDL_log
+ * \sa SDL_pow
+ */
+extern SDL_DECLSPEC double SDLCALL SDL_log10(double x);
+/**
+ * Compute the base-10 logarithm of `x`.
+ *
+ * Domain: `0 < x <= INF`
+ *
+ * Range: `-INF <= y <= INF`
+ *
+ * It is an error for `x` to be less than or equal to 0.
+ *
+ * This function operates on single-precision floating point values, use
+ * SDL_log10 for double-precision floats.
+ *
+ * This function may use a different approximation across different versions,
+ * platforms and configurations. i.e, it can return a different value given
+ * the same input on different machines or operating systems, or if SDL is
+ * updated.
+ *
+ * \param x floating point value. Must be greater than 0.
+ * \returns the logarithm of `x`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_log10
+ * \sa SDL_logf
+ * \sa SDL_powf
+ */
+extern SDL_DECLSPEC float SDLCALL SDL_log10f(float x);
+/**
+ * Split `x` into integer and fractional parts
+ *
+ * This function operates on double-precision floating point values, use
+ * SDL_modff for single-precision floats.
+ *
+ * \param x floating point value.
+ * \param y output pointer to store the integer part of `x`.
+ * \returns the fractional part of `x`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_modff
+ * \sa SDL_trunc
+ * \sa SDL_fmod
+ */
+extern SDL_DECLSPEC double SDLCALL SDL_modf(double x, double *y);
+/**
+ * Split `x` into integer and fractional parts
+ *
+ * This function operates on single-precision floating point values, use
+ * SDL_modf for double-precision floats.
+ *
+ * \param x floating point value.
+ * \param y output pointer to store the integer part of `x`.
+ * \returns the fractional part of `x`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_modf
+ * \sa SDL_truncf
+ * \sa SDL_fmodf
+ */
+extern SDL_DECLSPEC float SDLCALL SDL_modff(float x, float *y);
+/**
+ * Raise `x` to the power `y`
+ *
+ * Domain: `-INF <= x <= INF`, `-INF <= y <= INF`
+ *
+ * Range: `-INF <= z <= INF`
+ *
+ * If `y` is the base of the natural logarithm (e), consider using SDL_exp
+ * instead.
+ *
+ * This function operates on double-precision floating point values, use
+ * SDL_powf for single-precision floats.
+ *
+ * This function may use a different approximation across different versions,
+ * platforms and configurations. i.e, it can return a different value given
+ * the same input on different machines or operating systems, or if SDL is
+ * updated.
+ *
+ * \param x the base.
+ * \param y the exponent.
+ * \returns `x` raised to the power `y`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_powf
+ * \sa SDL_exp
+ * \sa SDL_log
+ */
+extern SDL_DECLSPEC double SDLCALL SDL_pow(double x, double y);
+/**
+ * Raise `x` to the power `y`
+ *
+ * Domain: `-INF <= x <= INF`, `-INF <= y <= INF`
+ *
+ * Range: `-INF <= z <= INF`
+ *
+ * If `y` is the base of the natural logarithm (e), consider using SDL_exp
+ * instead.
+ *
+ * This function operates on single-precision floating point values, use
+ * SDL_pow for double-precision floats.
+ *
+ * This function may use a different approximation across different versions,
+ * platforms and configurations. i.e, it can return a different value given
+ * the same input on different machines or operating systems, or if SDL is
+ * updated.
+ *
+ * \param x the base.
+ * \param y the exponent.
+ * \returns `x` raised to the power `y`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_pow
+ * \sa SDL_expf
+ * \sa SDL_logf
+ */
+extern SDL_DECLSPEC float SDLCALL SDL_powf(float x, float y);
+/**
+ * Round `x` to the nearest integer.
+ *
+ * Rounds `x` to the nearest integer. Values halfway between integers will be
+ * rounded away from zero.
+ *
+ * Domain: `-INF <= x <= INF`
+ *
+ * Range: `-INF <= y <= INF`, y integer
+ *
+ * This function operates on double-precision floating point values, use
+ * SDL_roundf for single-precision floats. To get the result as an integer
+ * type, use SDL_lround.
+ *
+ * \param x floating point value.
+ * \returns the nearest integer to `x`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_roundf
+ * \sa SDL_lround
+ * \sa SDL_floor
+ * \sa SDL_ceil
+ * \sa SDL_trunc
+ */
+extern SDL_DECLSPEC double SDLCALL SDL_round(double x);
+/**
+ * Round `x` to the nearest integer.
+ *
+ * Rounds `x` to the nearest integer. Values halfway between integers will be
+ * rounded away from zero.
+ *
+ * Domain: `-INF <= x <= INF`
+ *
+ * Range: `-INF <= y <= INF`, y integer
+ *
+ * This function operates on single-precision floating point values, use
+ * SDL_round for double-precision floats. To get the result as an integer
+ * type, use SDL_lroundf.
+ *
+ * \param x floating point value.
+ * \returns the nearest integer to `x`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_round
+ * \sa SDL_lroundf
+ * \sa SDL_floorf
+ * \sa SDL_ceilf
+ * \sa SDL_truncf
+ */
+extern SDL_DECLSPEC float SDLCALL SDL_roundf(float x);
+/**
+ * Round `x` to the nearest integer representable as a long
+ *
+ * Rounds `x` to the nearest integer. Values halfway between integers will be
+ * rounded away from zero.
+ *
+ * Domain: `-INF <= x <= INF`
+ *
+ * Range: `MIN_LONG <= y <= MAX_LONG`
+ *
+ * This function operates on double-precision floating point values, use
+ * SDL_lroundf for single-precision floats. To get the result as a
+ * floating-point type, use SDL_round.
+ *
+ * \param x floating point value.
+ * \returns the nearest integer to `x`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_lroundf
+ * \sa SDL_round
+ * \sa SDL_floor
+ * \sa SDL_ceil
+ * \sa SDL_trunc
+ */
+extern SDL_DECLSPEC long SDLCALL SDL_lround(double x);
+/**
+ * Round `x` to the nearest integer representable as a long
+ *
+ * Rounds `x` to the nearest integer. Values halfway between integers will be
+ * rounded away from zero.
+ *
+ * Domain: `-INF <= x <= INF`
+ *
+ * Range: `MIN_LONG <= y <= MAX_LONG`
+ *
+ * This function operates on single-precision floating point values, use
+ * SDL_lround for double-precision floats. To get the result as a
+ * floating-point type, use SDL_roundf.
+ *
+ * \param x floating point value.
+ * \returns the nearest integer to `x`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_lround
+ * \sa SDL_roundf
+ * \sa SDL_floorf
+ * \sa SDL_ceilf
+ * \sa SDL_truncf
+ */
+extern SDL_DECLSPEC long SDLCALL SDL_lroundf(float x);
+/**
+ * Scale `x` by an integer power of two.
+ *
+ * Multiplies `x` by the `n`th power of the floating point radix (always 2).
+ *
+ * Domain: `-INF <= x <= INF`, `n` integer
+ *
+ * Range: `-INF <= y <= INF`
+ *
+ * This function operates on double-precision floating point values, use
+ * SDL_scalbnf for single-precision floats.
+ *
+ * \param x floating point value to be scaled.
+ * \param n integer exponent.
+ * \returns `x * 2^n`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_scalbnf
+ * \sa SDL_pow
+ */
+extern SDL_DECLSPEC double SDLCALL SDL_scalbn(double x, int n);
+/**
+ * Scale `x` by an integer power of two.
+ *
+ * Multiplies `x` by the `n`th power of the floating point radix (always 2).
+ *
+ * Domain: `-INF <= x <= INF`, `n` integer
+ *
+ * Range: `-INF <= y <= INF`
+ *
+ * This function operates on single-precision floating point values, use
+ * SDL_scalbn for double-precision floats.
+ *
+ * \param x floating point value to be scaled.
+ * \param n integer exponent.
+ * \returns `x * 2^n`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_scalbn
+ * \sa SDL_powf
+ */
+extern SDL_DECLSPEC float SDLCALL SDL_scalbnf(float x, int n);
+/**
+ * Compute the sine of `x`.
+ *
+ * Domain: `-INF <= x <= INF`
+ *
+ * Range: `-1 <= y <= 1`
+ *
+ * This function operates on double-precision floating point values, use
+ * SDL_sinf for single-precision floats.
+ *
+ * This function may use a different approximation across different versions,
+ * platforms and configurations. i.e, it can return a different value given
+ * the same input on different machines or operating systems, or if SDL is
+ * updated.
+ *
+ * \param x floating point value, in radians.
+ * \returns sine of `x`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_sinf
+ * \sa SDL_asin
+ * \sa SDL_cos
+ */
+extern SDL_DECLSPEC double SDLCALL SDL_sin(double x);
+/**
+ * Compute the sine of `x`.
+ *
+ * Domain: `-INF <= x <= INF`
+ *
+ * Range: `-1 <= y <= 1`
+ *
+ * This function operates on single-precision floating point values, use
+ * SDL_sin for double-precision floats.
+ *
+ * This function may use a different approximation across different versions,
+ * platforms and configurations. i.e, it can return a different value given
+ * the same input on different machines or operating systems, or if SDL is
+ * updated.
+ *
+ * \param x floating point value, in radians.
+ * \returns sine of `x`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_sin
+ * \sa SDL_asinf
+ * \sa SDL_cosf
+ */
+extern SDL_DECLSPEC float SDLCALL SDL_sinf(float x);
+/**
+ * Compute the square root of `x`.
+ *
+ * Domain: `0 <= x <= INF`
+ *
+ * Range: `0 <= y <= INF`
+ *
+ * This function operates on double-precision floating point values, use
+ * SDL_sqrtf for single-precision floats.
+ *
+ * This function may use a different approximation across different versions,
+ * platforms and configurations. i.e, it can return a different value given
+ * the same input on different machines or operating systems, or if SDL is
+ * updated.
+ *
+ * \param x floating point value. Must be greater than or equal to 0.
+ * \returns square root of `x`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_sqrtf
+ */
+extern SDL_DECLSPEC double SDLCALL SDL_sqrt(double x);
+/**
+ * Compute the square root of `x`.
+ *
+ * Domain: `0 <= x <= INF`
+ *
+ * Range: `0 <= y <= INF`
+ *
+ * This function operates on single-precision floating point values, use
+ * SDL_sqrt for double-precision floats.
+ *
+ * This function may use a different approximation across different versions,
+ * platforms and configurations. i.e, it can return a different value given
+ * the same input on different machines or operating systems, or if SDL is
+ * updated.
+ *
+ * \param x floating point value. Must be greater than or equal to 0.
+ * \returns square root of `x`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_sqrt
+ */
+extern SDL_DECLSPEC float SDLCALL SDL_sqrtf(float x);
+/**
+ * Compute the tangent of `x`.
+ *
+ * Domain: `-INF <= x <= INF`
+ *
+ * Range: `-INF <= y <= INF`
+ *
+ * This function operates on double-precision floating point values, use
+ * SDL_tanf for single-precision floats.
+ *
+ * This function may use a different approximation across different versions,
+ * platforms and configurations. i.e, it can return a different value given
+ * the same input on different machines or operating systems, or if SDL is
+ * updated.
+ *
+ * \param x floating point value, in radians.
+ * \returns tangent of `x`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_tanf
+ * \sa SDL_sin
+ * \sa SDL_cos
+ * \sa SDL_atan
+ * \sa SDL_atan2
+ */
+extern SDL_DECLSPEC double SDLCALL SDL_tan(double x);
+/**
+ * Compute the tangent of `x`.
+ *
+ * Domain: `-INF <= x <= INF`
+ *
+ * Range: `-INF <= y <= INF`
+ *
+ * This function operates on single-precision floating point values, use
+ * SDL_tan for double-precision floats.
+ *
+ * This function may use a different approximation across different versions,
+ * platforms and configurations. i.e, it can return a different value given
+ * the same input on different machines or operating systems, or if SDL is
+ * updated.
+ *
+ * \param x floating point value, in radians.
+ * \returns tangent of `x`.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_tan
+ * \sa SDL_sinf
+ * \sa SDL_cosf
+ * \sa SDL_atanf
+ * \sa SDL_atan2f
+ */
+extern SDL_DECLSPEC float SDLCALL SDL_tanf(float x);
+/**
+ * An opaque handle representing string encoding conversion state.
+ *
+ * \since This datatype is available since SDL 3.2.0.
+ *
+ * \sa SDL_iconv_open
+ */
+typedef struct SDL_iconv_data_t *SDL_iconv_t;
+/**
+ * This function allocates a context for the specified character set
+ * conversion.
+ *
+ * \param tocode The target character encoding, must not be NULL.
+ * \param fromcode The source character encoding, must not be NULL.
+ * \returns a handle that must be freed with SDL_iconv_close, or
+ *          SDL_ICONV_ERROR on failure.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_iconv
+ * \sa SDL_iconv_close
+ * \sa SDL_iconv_string
+ */
+extern SDL_DECLSPEC SDL_iconv_t SDLCALL SDL_iconv_open(const char *tocode,
+                                                   const char *fromcode);
+/**
+ * This function frees a context used for character set conversion.
+ *
+ * \param cd The character set conversion handle.
+ * \returns 0 on success, or -1 on failure.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_iconv
+ * \sa SDL_iconv_open
+ * \sa SDL_iconv_string
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_iconv_close(SDL_iconv_t cd);
+/**
+ * This function converts text between encodings, reading from and writing to
+ * a buffer.
+ *
+ * It returns the number of succesful conversions on success. On error,
+ * SDL_ICONV_E2BIG is returned when the output buffer is too small, or
+ * SDL_ICONV_EILSEQ is returned when an invalid input sequence is encountered,
+ * or SDL_ICONV_EINVAL is returned when an incomplete input sequence is
+ * encountered.
+ *
+ * On exit:
+ *
+ * - inbuf will point to the beginning of the next multibyte sequence. On
+ *   error, this is the location of the problematic input sequence. On
+ *   success, this is the end of the input sequence.
+ * - inbytesleft will be set to the number of bytes left to convert, which
+ *   will be 0 on success.
+ * - outbuf will point to the location where to store the next output byte.
+ * - outbytesleft will be set to the number of bytes left in the output
+ *   buffer.
+ *
+ * \param cd The character set conversion context, created in
+ *           SDL_iconv_open().
+ * \param inbuf Address of variable that points to the first character of the
+ *              input sequence.
+ * \param inbytesleft The number of bytes in the input buffer.
+ * \param outbuf Address of variable that points to the output buffer.
+ * \param outbytesleft The number of bytes in the output buffer.
+ * \returns the number of conversions on success, or a negative error code.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_iconv_open
+ * \sa SDL_iconv_close
+ * \sa SDL_iconv_string
+ */
+extern SDL_DECLSPEC size_t SDLCALL SDL_iconv(SDL_iconv_t cd, const char **inbuf,
+                                         size_t *inbytesleft, char **outbuf,
+                                         size_t *outbytesleft);
+#define SDL_ICONV_ERROR     (size_t)-1  /**< Generic error. Check SDL_GetError()? */
+#define SDL_ICONV_E2BIG     (size_t)-2  /**< Output buffer was too small. */
+#define SDL_ICONV_EILSEQ    (size_t)-3  /**< Invalid input sequence was encountered. */
+#define SDL_ICONV_EINVAL    (size_t)-4  /**< Incomplete input sequence was encountered. */
+/**
+ * Helper function to convert a string's encoding in one call.
+ *
+ * This function converts a buffer or string between encodings in one pass.
+ *
+ * The string does not need to be NULL-terminated; this function operates on
+ * the number of bytes specified in `inbytesleft` whether there is a NULL
+ * character anywhere in the buffer.
+ *
+ * The returned string is owned by the caller, and should be passed to
+ * SDL_free when no longer needed.
+ *
+ * \param tocode the character encoding of the output string. Examples are
+ *               "UTF-8", "UCS-4", etc.
+ * \param fromcode the character encoding of data in `inbuf`.
+ * \param inbuf the string to convert to a different encoding.
+ * \param inbytesleft the size of the input string _in bytes_.
+ * \returns a new string, converted to the new encoding, or NULL on error.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_iconv_open
+ * \sa SDL_iconv_close
+ * \sa SDL_iconv
+ */
+extern SDL_DECLSPEC char * SDLCALL SDL_iconv_string(const char *tocode,
+                                               const char *fromcode,
+                                               const char *inbuf,
+                                               size_t inbytesleft);
+/* Some helper macros for common SDL_iconv_string cases... */
+/**
+ * Convert a UTF-8 string to the current locale's character encoding.
+ *
+ * This is a helper macro that might be more clear than calling
+ * SDL_iconv_string directly. However, it double-evaluates its parameter, so
+ * do not use an expression with side-effects here.
+ *
+ * \param S the string to convert.
+ * \returns a new string, converted to the new encoding, or NULL on error.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_iconv_utf8_locale(S)    SDL_iconv_string("", "UTF-8", S, SDL_strlen(S)+1)
+/**
+ * Convert a UTF-8 string to UCS-2.
+ *
+ * This is a helper macro that might be more clear than calling
+ * SDL_iconv_string directly. However, it double-evaluates its parameter, so
+ * do not use an expression with side-effects here.
+ *
+ * \param S the string to convert.
+ * \returns a new string, converted to the new encoding, or NULL on error.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_iconv_utf8_ucs2(S)      (Uint16 *)SDL_iconv_string("UCS-2", "UTF-8", S, SDL_strlen(S)+1)
+/**
+ * Convert a UTF-8 string to UCS-4.
+ *
+ * This is a helper macro that might be more clear than calling
+ * SDL_iconv_string directly. However, it double-evaluates its parameter, so
+ * do not use an expression with side-effects here.
+ *
+ * \param S the string to convert.
+ * \returns a new string, converted to the new encoding, or NULL on error.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_iconv_utf8_ucs4(S)      (Uint32 *)SDL_iconv_string("UCS-4", "UTF-8", S, SDL_strlen(S)+1)
+/**
+ * Convert a wchar_t string to UTF-8.
+ *
+ * This is a helper macro that might be more clear than calling
+ * SDL_iconv_string directly. However, it double-evaluates its parameter, so
+ * do not use an expression with side-effects here.
+ *
+ * \param S the string to convert.
+ * \returns a new string, converted to the new encoding, or NULL on error.
+ *
+ * \since This macro is available since SDL 3.2.0.
+ */
+#define SDL_iconv_wchar_utf8(S)     SDL_iconv_string("UTF-8", "WCHAR_T", (char *)S, (SDL_wcslen(S)+1)*sizeof(wchar_t))
+/* force builds using Clang's static analysis tools to use literal C runtime
+   here, since there are possibly tests that are ineffective otherwise. */
+#if defined(__clang_analyzer__) && !defined(SDL_DISABLE_ANALYZE_MACROS)
+/* The analyzer knows about strlcpy even when the system doesn't provide it */
+#if !defined(HAVE_STRLCPY) && !defined(strlcpy)
+size_t strlcpy(char *dst, const char *src, size_t size);
+#endif
+/* The analyzer knows about strlcat even when the system doesn't provide it */
+#if !defined(HAVE_STRLCAT) && !defined(strlcat)
+size_t strlcat(char *dst, const char *src, size_t size);
+#endif
+#if !defined(HAVE_WCSLCPY) && !defined(wcslcpy)
+size_t wcslcpy(wchar_t *dst, const wchar_t *src, size_t size);
+#endif
+#if !defined(HAVE_WCSLCAT) && !defined(wcslcat)
+size_t wcslcat(wchar_t *dst, const wchar_t *src, size_t size);
+#endif
+/* strdup is not ANSI but POSIX, and its prototype might be hidden... */
+char *strdup(const char *str);
+/* Starting LLVM 16, the analyser errors out if these functions do not have
+   their prototype defined (clang-diagnostic-implicit-function-declaration) */
+#include <stdio.h>
+#include <stdlib.h>
+#define SDL_malloc malloc
+#define SDL_calloc calloc
+#define SDL_realloc realloc
+#define SDL_free free
+#ifndef SDL_memcpy
+#define SDL_memcpy memcpy
+#endif
+#ifndef SDL_memmove
+#define SDL_memmove memmove
+#endif
+#ifndef SDL_memset
+#define SDL_memset memset
+#endif
+#define SDL_memcmp memcmp
+#define SDL_strlcpy strlcpy
+#define SDL_strlcat strlcat
+#define SDL_strlen strlen
+#define SDL_wcslen wcslen
+#define SDL_wcslcpy wcslcpy
+#define SDL_wcslcat wcslcat
+#define SDL_strdup strdup
+#define SDL_wcsdup wcsdup
+#define SDL_strchr strchr
+#define SDL_strrchr strrchr
+#define SDL_strstr strstr
+#define SDL_wcsstr wcsstr
+#define SDL_strtok_r strtok_r
+#define SDL_strcmp strcmp
+#define SDL_wcscmp wcscmp
+#define SDL_strncmp strncmp
+#define SDL_wcsncmp wcsncmp
+#define SDL_strcasecmp strcasecmp
+#define SDL_strncasecmp strncasecmp
+#define SDL_strpbrk strpbrk
+#define SDL_sscanf sscanf
+#define SDL_vsscanf vsscanf
+#define SDL_snprintf snprintf
+#define SDL_vsnprintf vsnprintf
+#endif
+/**
+ * Multiply two integers, checking for overflow.
+ *
+ * If `a * b` would overflow, return false.
+ *
+ * Otherwise store `a * b` via ret and return true.
+ *
+ * \param a the multiplicand.
+ * \param b the multiplier.
+ * \param ret on non-overflow output, stores the multiplication result, may
+ *            not be NULL.
+ * \returns false on overflow, true if result is multiplied without overflow.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+SDL_FORCE_INLINE bool SDL_size_mul_check_overflow(size_t a, size_t b, size_t *ret)
+{
+    if (a != 0 && b > SDL_SIZE_MAX / a) {
+        return false;
+    }
+    *ret = a * b;
+    return true;
+}
+#ifndef SDL_WIKI_DOCUMENTATION_SECTION
+#if SDL_HAS_BUILTIN(__builtin_mul_overflow)
+/* This needs to be wrapped in an inline rather than being a direct #define,
+ * because __builtin_mul_overflow() is type-generic, but we want to be
+ * consistent about interpreting a and b as size_t. */
+SDL_FORCE_INLINE bool SDL_size_mul_check_overflow_builtin(size_t a, size_t b, size_t *ret)
+{
+    return (__builtin_mul_overflow(a, b, ret) == 0);
+}
+#define SDL_size_mul_check_overflow(a, b, ret) SDL_size_mul_check_overflow_builtin(a, b, ret)
+#endif
+#endif
+/**
+ * Add two integers, checking for overflow.
+ *
+ * If `a + b` would overflow, return false.
+ *
+ * Otherwise store `a + b` via ret and return true.
+ *
+ * \param a the first addend.
+ * \param b the second addend.
+ * \param ret on non-overflow output, stores the addition result, may not be
+ *            NULL.
+ * \returns false on overflow, true if result is added without overflow.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+SDL_FORCE_INLINE bool SDL_size_add_check_overflow(size_t a, size_t b, size_t *ret)
+{
+    if (b > SDL_SIZE_MAX - a) {
+        return false;
+    }
+    *ret = a + b;
+    return true;
+}
+#ifndef SDL_WIKI_DOCUMENTATION_SECTION
+#if SDL_HAS_BUILTIN(__builtin_add_overflow)
+/* This needs to be wrapped in an inline rather than being a direct #define,
+ * the same as the call to __builtin_mul_overflow() above. */
+SDL_FORCE_INLINE bool SDL_size_add_check_overflow_builtin(size_t a, size_t b, size_t *ret)
+{
+    return (__builtin_add_overflow(a, b, ret) == 0);
+}
+#define SDL_size_add_check_overflow(a, b, ret) SDL_size_add_check_overflow_builtin(a, b, ret)
+#endif
+#endif
+/* This is a generic function pointer which should be cast to the type you expect */
+#ifdef SDL_WIKI_DOCUMENTATION_SECTION
+/**
+ * A generic function pointer.
+ *
+ * In theory, generic function pointers should use this, instead of `void *`,
+ * since some platforms could treat code addresses differently than data
+ * addresses. Although in current times no popular platforms make this
+ * distinction, it is more correct and portable to use the correct type for a
+ * generic pointer.
+ *
+ * If for some reason you need to force this typedef to be an actual `void *`,
+ * perhaps to work around a compiler or existing code, you can define
+ * `SDL_FUNCTION_POINTER_IS_VOID_POINTER` before including any SDL headers.
+ *
+ * \since This datatype is available since SDL 3.2.0.
+ */
+typedef void (*SDL_FunctionPointer)(void);
+#elif defined(SDL_FUNCTION_POINTER_IS_VOID_POINTER)
+typedef void *SDL_FunctionPointer;
+#else
+typedef void (*SDL_FunctionPointer)(void);
+#endif
+/* Ends C function definitions when using C++ */
+#ifdef __cplusplus
+}
+#endif
+#include <SDL3/SDL_close_code.h>
+#endif /* SDL_stdinc_h_ */