Squashed 'external/SDL/' content from commit 716c767b7

git-subtree-dir: external/SDL
git-subtree-split: 716c767b7e7099fb0e2fda9db59227a7e1d1d8a4

test/torturethread.c

@@ -0,0 +1,127 @@
+/*
+  Copyright (C) 1997-2026 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.
+*/
+
+/* Simple test of the SDL threading code */
+
+#include <stdlib.h>
+#include <signal.h>
+
+#include <SDL3/SDL.h>
+#include <SDL3/SDL_main.h>
+#include <SDL3/SDL_test.h>
+
+#ifdef SDL_PLATFORM_DOS
+#define NUMTHREADS 3  /* DOS cooperative scheduler has limited thread slots */
+#else
+#define NUMTHREADS 10
+#endif
+
+static SDL_AtomicInt time_for_threads_to_die[NUMTHREADS];
+
+/* Call this instead of exit(), so we can clean up SDL: atexit() is evil. */
+static void
+quit(int rc)
+{
+    SDL_Quit();
+    /* Let 'main()' return normally */
+    if (rc != 0) {
+        exit(rc);
+    }
+}
+
+static int SDLCALL
+SubThreadFunc(void *data)
+{
+    SDL_AtomicInt *flag = (SDL_AtomicInt *)data;
+    while (!SDL_GetAtomicInt(flag)) {
+        SDL_Delay(10);
+    }
+    return 0;
+}
+
+static int SDLCALL
+ThreadFunc(void *data)
+{
+    SDL_Thread *sub_threads[NUMTHREADS];
+    SDL_AtomicInt flags[NUMTHREADS];
+    int i;
+    int tid = (int)(uintptr_t)data;
+
+    SDL_Log("Creating Thread %d", tid);
+
+    for (i = 0; i < NUMTHREADS; i++) {
+        char name[64];
+        (void)SDL_snprintf(name, sizeof(name), "Child%d_%d", tid, i);
+        SDL_SetAtomicInt(&flags[i], 0);
+        sub_threads[i] = SDL_CreateThread(SubThreadFunc, name, &flags[i]);
+    }
+
+    SDL_Log("Thread '%d' waiting for signal", tid);
+    while (SDL_GetAtomicInt(&time_for_threads_to_die[tid]) != 1) {
+#ifdef SDL_PLATFORM_DOS
+        SDL_Delay(0); /* Yield for cooperative threading */
+#endif
+    }
+
+    SDL_Log("Thread '%d' sending signals to subthreads", tid);
+    for (i = 0; i < NUMTHREADS; i++) {
+        SDL_SetAtomicInt(&flags[i], 1);
+        SDL_WaitThread(sub_threads[i], NULL);
+    }
+
+    SDL_Log("Thread '%d' exiting!", tid);
+
+    return 0;
+}
+
+int main(int argc, char *argv[])
+{
+    SDL_Thread *threads[NUMTHREADS];
+    int i;
+    SDLTest_CommonState *state;
+
+    /* Initialize test framework */
+    state = SDLTest_CommonCreateState(argv, 0);
+    if (!state) {
+        return 1;
+    }
+
+    if (!SDLTest_CommonDefaultArgs(state, argc, argv)) {
+        SDL_Quit();
+        SDLTest_CommonDestroyState(state);
+        return 1;
+    }
+
+    (void)signal(SIGSEGV, SIG_DFL);
+    for (i = 0; i < NUMTHREADS; i++) {
+        char name[64];
+        (void)SDL_snprintf(name, sizeof(name), "Parent%d", i);
+        SDL_SetAtomicInt(&time_for_threads_to_die[i], 0);
+        threads[i] = SDL_CreateThread(ThreadFunc, name, (void *)(uintptr_t)i);
+
+        if (threads[i] == NULL) {
+            SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't create thread: %s", SDL_GetError());
+            quit(1);
+        }
+    }
+
+    for (i = 0; i < NUMTHREADS; i++) {
+        SDL_SetAtomicInt(&time_for_threads_to_die[i], 1);
+    }
+
+    for (i = 0; i < NUMTHREADS; i++) {
+        SDL_WaitThread(threads[i], NULL);
+    }
+    SDL_Quit();
+    SDLTest_CommonDestroyState(state);
+    return 0;
+}