1 files changed, 156 insertions, 0 deletions

diff --git a/SDL-3.2.8/src/core/linux/SDL_system_theme.c b/SDL-3.2.8/src/core/linux/SDL_system_theme.c
new file mode 100644
index 0000000..6d6087d
--- /dev/null
+++ b/SDL-3.2.8/src/core/linux/SDL_system_theme.c
@@ -0,0 +1,156 @@
+/*
+  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.
+*/
+#include "SDL_internal.h"
+
+#include "SDL_dbus.h"
+#include "SDL_system_theme.h"
+#include "../../video/SDL_sysvideo.h"
+
+#include <unistd.h>
+
+#define PORTAL_DESTINATION "org.freedesktop.portal.Desktop"
+#define PORTAL_PATH "/org/freedesktop/portal/desktop"
+#define PORTAL_INTERFACE "org.freedesktop.portal.Settings"
+#define PORTAL_METHOD "Read"
+
+#define SIGNAL_INTERFACE "org.freedesktop.portal.Settings"
+#define SIGNAL_NAMESPACE "org.freedesktop.appearance"
+#define SIGNAL_NAME "SettingChanged"
+#define SIGNAL_KEY "color-scheme"
+
+typedef struct SystemThemeData
+{
+    SDL_DBusContext *dbus;
+    SDL_SystemTheme theme;
+} SystemThemeData;
+
+static SystemThemeData system_theme_data;
+
+static bool DBus_ExtractThemeVariant(DBusMessageIter *iter, SDL_SystemTheme *theme) {
+    SDL_DBusContext *dbus = system_theme_data.dbus;
+    Uint32 color_scheme;
+    DBusMessageIter variant_iter;
+
+    if (dbus->message_iter_get_arg_type(iter) != DBUS_TYPE_VARIANT)
+        return false;
+    dbus->message_iter_recurse(iter, &variant_iter);
+    if (dbus->message_iter_get_arg_type(&variant_iter) != DBUS_TYPE_UINT32)
+        return false;
+    dbus->message_iter_get_basic(&variant_iter, &color_scheme);
+    switch (color_scheme) {
+        case 0:
+            *theme = SDL_SYSTEM_THEME_UNKNOWN;
+            break;
+        case 1:
+            *theme = SDL_SYSTEM_THEME_DARK;
+            break;
+        case 2:
+            *theme = SDL_SYSTEM_THEME_LIGHT;
+            break;
+    }
+    return true;
+}
+
+static DBusHandlerResult DBus_MessageFilter(DBusConnection *conn, DBusMessage *msg, void *data) {
+    SDL_DBusContext *dbus = (SDL_DBusContext *)data;
+
+    if (dbus->message_is_signal(msg, SIGNAL_INTERFACE, SIGNAL_NAME)) {
+        DBusMessageIter signal_iter;
+        const char *namespace, *key;
+
+        dbus->message_iter_init(msg, &signal_iter);
+        // Check if the parameters are what we expect
+        if (dbus->message_iter_get_arg_type(&signal_iter) != DBUS_TYPE_STRING)
+            goto not_our_signal;
+        dbus->message_iter_get_basic(&signal_iter, &namespace);
+        if (SDL_strcmp(SIGNAL_NAMESPACE, namespace) != 0)
+            goto not_our_signal;
+
+        if (!dbus->message_iter_next(&signal_iter))
+            goto not_our_signal;
+
+        if (dbus->message_iter_get_arg_type(&signal_iter) != DBUS_TYPE_STRING)
+            goto not_our_signal;
+        dbus->message_iter_get_basic(&signal_iter, &key);
+        if (SDL_strcmp(SIGNAL_KEY, key) != 0)
+            goto not_our_signal;
+
+        if (!dbus->message_iter_next(&signal_iter))
+            goto not_our_signal;
+
+        if (!DBus_ExtractThemeVariant(&signal_iter, &system_theme_data.theme))
+            goto not_our_signal;
+
+        SDL_SetSystemTheme(system_theme_data.theme);
+        return DBUS_HANDLER_RESULT_HANDLED;
+    }
+not_our_signal:
+    return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
+}
+
+bool SDL_SystemTheme_Init(void)
+{
+    SDL_DBusContext *dbus = SDL_DBus_GetContext();
+    DBusMessage *msg;
+    static const char *namespace = SIGNAL_NAMESPACE;
+    static const char *key = SIGNAL_KEY;
+
+    system_theme_data.theme = SDL_SYSTEM_THEME_UNKNOWN;
+    system_theme_data.dbus = dbus;
+    if (!dbus) {
+        return false;
+    }
+
+    msg = dbus->message_new_method_call(PORTAL_DESTINATION, PORTAL_PATH, PORTAL_INTERFACE, PORTAL_METHOD);
+    if (msg) {
+        if (dbus->message_append_args(msg, DBUS_TYPE_STRING, &namespace, DBUS_TYPE_STRING, &key, DBUS_TYPE_INVALID)) {
+            DBusMessage *reply = dbus->connection_send_with_reply_and_block(dbus->session_conn, msg, 300, NULL);
+            if (reply) {
+                DBusMessageIter reply_iter, variant_outer_iter;
+
+                dbus->message_iter_init(reply, &reply_iter);
+                // The response has signature <<u>>
+                if (dbus->message_iter_get_arg_type(&reply_iter) != DBUS_TYPE_VARIANT)
+                    goto incorrect_type;
+                dbus->message_iter_recurse(&reply_iter, &variant_outer_iter);
+                if (!DBus_ExtractThemeVariant(&variant_outer_iter, &system_theme_data.theme))
+                    goto incorrect_type;
+incorrect_type:
+                dbus->message_unref(reply);
+            }
+        }
+        dbus->message_unref(msg);
+    }
+
+    dbus->bus_add_match(dbus->session_conn,
+                        "type='signal', interface='"SIGNAL_INTERFACE"',"
+                        "member='"SIGNAL_NAME"', arg0='"SIGNAL_NAMESPACE"',"
+                        "arg1='"SIGNAL_KEY"'", NULL);
+    dbus->connection_add_filter(dbus->session_conn,
+                                &DBus_MessageFilter, dbus, NULL);
+    dbus->connection_flush(dbus->session_conn);
+    return true;
+}
+
+SDL_SystemTheme SDL_SystemTheme_Get(void)
+{
+    return system_theme_data.theme;
+}