Merge commit 'dec0d4ec4153bf9fc2b78ae6c2df45b6ea8dde7a' as 'external/sdl/SDL'

external/sdl/SDL/src/thread/generic/SDL_syscond.c

@@ -0,0 +1,218 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2023 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"
+
+/* An implementation of condition variables using semaphores and mutexes */
+/*
+   This implementation borrows heavily from the BeOS condition variable
+   implementation, written by Christopher Tate and Owen Smith.  Thanks!
+ */
+
+#include "../generic/SDL_syscond_c.h"
+
+/* If two implementations are to be compiled into SDL (the active one
+ * will be chosen at runtime), the function names need to be
+ * suffixed
+ */
+#ifndef SDL_THREAD_GENERIC_COND_SUFFIX
+#define SDL_CreateCondition_generic      SDL_CreateCondition
+#define SDL_DestroyCondition_generic     SDL_DestroyCondition
+#define SDL_SignalCondition_generic      SDL_SignalCondition
+#define SDL_BroadcastCondition_generic   SDL_BroadcastCondition
+#define SDL_WaitConditionTimeoutNS_generic SDL_WaitConditionTimeoutNS
+#endif
+
+typedef struct SDL_cond_generic
+{
+    SDL_Mutex *lock;
+    int waiting;
+    int signals;
+    SDL_Semaphore *wait_sem;
+    SDL_Semaphore *wait_done;
+} SDL_cond_generic;
+
+/* Create a condition variable */
+SDL_Condition *SDL_CreateCondition_generic(void)
+{
+    SDL_cond_generic *cond;
+
+    cond = (SDL_cond_generic *)SDL_malloc(sizeof(SDL_cond_generic));
+    if (cond) {
+        cond->lock = SDL_CreateMutex();
+        cond->wait_sem = SDL_CreateSemaphore(0);
+        cond->wait_done = SDL_CreateSemaphore(0);
+        cond->waiting = cond->signals = 0;
+        if (!cond->lock || !cond->wait_sem || !cond->wait_done) {
+            SDL_DestroyCondition_generic((SDL_Condition *)cond);
+            cond = NULL;
+        }
+    } else {
+        SDL_OutOfMemory();
+    }
+    return (SDL_Condition *)cond;
+}
+
+/* Destroy a condition variable */
+void SDL_DestroyCondition_generic(SDL_Condition *_cond)
+{
+    SDL_cond_generic *cond = (SDL_cond_generic *)_cond;
+    if (cond) {
+        if (cond->wait_sem) {
+            SDL_DestroySemaphore(cond->wait_sem);
+        }
+        if (cond->wait_done) {
+            SDL_DestroySemaphore(cond->wait_done);
+        }
+        if (cond->lock) {
+            SDL_DestroyMutex(cond->lock);
+        }
+        SDL_free(cond);
+    }
+}
+
+/* Restart one of the threads that are waiting on the condition variable */
+int SDL_SignalCondition_generic(SDL_Condition *_cond)
+{
+    SDL_cond_generic *cond = (SDL_cond_generic *)_cond;
+    if (cond == NULL) {
+        return SDL_InvalidParamError("cond");
+    }
+
+    /* If there are waiting threads not already signalled, then
+       signal the condition and wait for the thread to respond.
+     */
+    SDL_LockMutex(cond->lock);
+    if (cond->waiting > cond->signals) {
+        ++cond->signals;
+        SDL_PostSemaphore(cond->wait_sem);
+        SDL_UnlockMutex(cond->lock);
+        SDL_WaitSemaphore(cond->wait_done);
+    } else {
+        SDL_UnlockMutex(cond->lock);
+    }
+
+    return 0;
+}
+
+/* Restart all threads that are waiting on the condition variable */
+int SDL_BroadcastCondition_generic(SDL_Condition *_cond)
+{
+    SDL_cond_generic *cond = (SDL_cond_generic *)_cond;
+    if (cond == NULL) {
+        return SDL_InvalidParamError("cond");
+    }
+
+    /* If there are waiting threads not already signalled, then
+       signal the condition and wait for the thread to respond.
+     */
+    SDL_LockMutex(cond->lock);
+    if (cond->waiting > cond->signals) {
+        int i, num_waiting;
+
+        num_waiting = (cond->waiting - cond->signals);
+        cond->signals = cond->waiting;
+        for (i = 0; i < num_waiting; ++i) {
+            SDL_PostSemaphore(cond->wait_sem);
+        }
+        /* Now all released threads are blocked here, waiting for us.
+           Collect them all (and win fabulous prizes!) :-)
+         */
+        SDL_UnlockMutex(cond->lock);
+        for (i = 0; i < num_waiting; ++i) {
+            SDL_WaitSemaphore(cond->wait_done);
+        }
+    } else {
+        SDL_UnlockMutex(cond->lock);
+    }
+
+    return 0;
+}
+
+/* Wait on the condition variable for at most 'timeoutNS' nanoseconds.
+   The mutex must be locked before entering this function!
+   The mutex is unlocked during the wait, and locked again after the wait.
+
+Typical use:
+
+Thread A:
+    SDL_LockMutex(lock);
+    while ( ! condition ) {
+        SDL_WaitCondition(cond, lock);
+    }
+    SDL_UnlockMutex(lock);
+
+Thread B:
+    SDL_LockMutex(lock);
+    ...
+    condition = true;
+    ...
+    SDL_SignalCondition(cond);
+    SDL_UnlockMutex(lock);
+ */
+int SDL_WaitConditionTimeoutNS_generic(SDL_Condition *_cond, SDL_Mutex *mutex, Sint64 timeoutNS)
+{
+    SDL_cond_generic *cond = (SDL_cond_generic *)_cond;
+    int retval;
+
+    if (cond == NULL) {
+        return SDL_InvalidParamError("cond");
+    }
+
+    /* Obtain the protection mutex, and increment the number of waiters.
+       This allows the signal mechanism to only perform a signal if there
+       are waiting threads.
+     */
+    SDL_LockMutex(cond->lock);
+    ++cond->waiting;
+    SDL_UnlockMutex(cond->lock);
+
+    /* Unlock the mutex, as is required by condition variable semantics */
+    SDL_UnlockMutex(mutex);
+
+    /* Wait for a signal */
+    retval = SDL_WaitSemaphoreTimeoutNS(cond->wait_sem, timeoutNS);
+
+    /* Let the signaler know we have completed the wait, otherwise
+       the signaler can race ahead and get the condition semaphore
+       if we are stopped between the mutex unlock and semaphore wait,
+       giving a deadlock.  See the following URL for details:
+       http://web.archive.org/web/20010914175514/http://www-classic.be.com/aboutbe/benewsletter/volume_III/Issue40.html#Workshop
+     */
+    SDL_LockMutex(cond->lock);
+    if (cond->signals > 0) {
+        /* If we timed out, we need to eat a condition signal */
+        if (retval > 0) {
+            SDL_WaitSemaphore(cond->wait_sem);
+        }
+        /* We always notify the signal thread that we are done */
+        SDL_PostSemaphore(cond->wait_done);
+
+        /* Signal handshake complete */
+        --cond->signals;
+    }
+    --cond->waiting;
+    SDL_UnlockMutex(cond->lock);
+
+    /* Lock the mutex, as is required by condition variable semantics */
+    SDL_LockMutex(mutex);
+
+    return retval;
+}

external/sdl/SDL/src/thread/generic/SDL_syscond_c.h

@@ -0,0 +1,36 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2023 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"
+
+#ifndef SDL_syscond_generic_h_
+#define SDL_syscond_generic_h_
+
+#ifdef SDL_THREAD_GENERIC_COND_SUFFIX
+
+SDL_Condition *SDL_CreateCondition_generic(void);
+void SDL_DestroyCondition_generic(SDL_Condition *cond);
+int SDL_SignalCondition_generic(SDL_Condition *cond);
+int SDL_BroadcastCondition_generic(SDL_Condition *cond);
+int SDL_WaitConditionTimeoutNS_generic(SDL_Condition *cond, SDL_Mutex *mutex, Sint64 timeoutNS);
+
+#endif /* SDL_THREAD_GENERIC_COND_SUFFIX */
+
+#endif /* SDL_syscond_generic_h_ */

external/sdl/SDL/src/thread/generic/SDL_sysmutex.c

@@ -0,0 +1,161 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2023 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"
+
+/* An implementation of mutexes using semaphores */
+
+#include "SDL_systhread_c.h"
+
+struct SDL_Mutex
+{
+    int recursive;
+    SDL_threadID owner;
+    SDL_Semaphore *sem;
+};
+
+/* Create a mutex */
+SDL_Mutex *SDL_CreateMutex(void)
+{
+    SDL_Mutex *mutex;
+
+    /* Allocate mutex memory */
+    mutex = (SDL_Mutex *)SDL_calloc(1, sizeof(*mutex));
+
+#ifndef SDL_THREADS_DISABLED
+    if (mutex) {
+        /* Create the mutex semaphore, with initial value 1 */
+        mutex->sem = SDL_CreateSemaphore(1);
+        mutex->recursive = 0;
+        mutex->owner = 0;
+        if (!mutex->sem) {
+            SDL_free(mutex);
+            mutex = NULL;
+        }
+    } else {
+        SDL_OutOfMemory();
+    }
+#endif /* !SDL_THREADS_DISABLED */
+
+    return mutex;
+}
+
+/* Free the mutex */
+void SDL_DestroyMutex(SDL_Mutex *mutex)
+{
+    if (mutex) {
+        if (mutex->sem) {
+            SDL_DestroySemaphore(mutex->sem);
+        }
+        SDL_free(mutex);
+    }
+}
+
+/* Lock the mutex */
+int SDL_LockMutex(SDL_Mutex *mutex) SDL_NO_THREAD_SAFETY_ANALYSIS /* clang doesn't know about NULL mutexes */
+{
+#ifdef SDL_THREADS_DISABLED
+    return 0;
+#else
+    SDL_threadID this_thread;
+
+    if (mutex == NULL) {
+        return 0;
+    }
+
+    this_thread = SDL_ThreadID();
+    if (mutex->owner == this_thread) {
+        ++mutex->recursive;
+    } else {
+        /* The order of operations is important.
+           We set the locking thread id after we obtain the lock
+           so unlocks from other threads will fail.
+         */
+        SDL_WaitSemaphore(mutex->sem);
+        mutex->owner = this_thread;
+        mutex->recursive = 0;
+    }
+
+    return 0;
+#endif /* SDL_THREADS_DISABLED */
+}
+
+/* try Lock the mutex */
+int SDL_TryLockMutex(SDL_Mutex *mutex)
+{
+#ifdef SDL_THREADS_DISABLED
+    return 0;
+#else
+    int retval = 0;
+    SDL_threadID this_thread;
+
+    if (mutex == NULL) {
+        return 0;
+    }
+
+    this_thread = SDL_ThreadID();
+    if (mutex->owner == this_thread) {
+        ++mutex->recursive;
+    } else {
+        /* The order of operations is important.
+         We set the locking thread id after we obtain the lock
+         so unlocks from other threads will fail.
+         */
+        retval = SDL_WaitSemaphore(mutex->sem);
+        if (retval == 0) {
+            mutex->owner = this_thread;
+            mutex->recursive = 0;
+        }
+    }
+
+    return retval;
+#endif /* SDL_THREADS_DISABLED */
+}
+
+/* Unlock the mutex */
+int SDL_UnlockMutex(SDL_Mutex *mutex) SDL_NO_THREAD_SAFETY_ANALYSIS /* clang doesn't know about NULL mutexes */
+{
+#ifdef SDL_THREADS_DISABLED
+    return 0;
+#else
+    if (mutex == NULL) {
+        return 0;
+    }
+
+    /* If we don't own the mutex, we can't unlock it */
+    if (SDL_ThreadID() != mutex->owner) {
+        return SDL_SetError("mutex not owned by this thread");
+    }
+
+    if (mutex->recursive) {
+        --mutex->recursive;
+    } else {
+        /* The order of operations is important.
+           First reset the owner so another thread doesn't lock
+           the mutex and set the ownership before we reset it,
+           then release the lock semaphore.
+         */
+        mutex->owner = 0;
+        SDL_PostSemaphore(mutex->sem);
+    }
+    return 0;
+#endif /* SDL_THREADS_DISABLED */
+}
+

external/sdl/SDL/src/thread/generic/SDL_sysmutex_c.h

@@ -0,0 +1,21 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2023 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"

external/sdl/SDL/src/thread/generic/SDL_sysrwlock.c

@@ -0,0 +1,185 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2023 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"
+
+/* An implementation of rwlocks using mutexes, condition variables, and atomics. */
+
+#include "SDL_systhread_c.h"
+
+#include "../generic/SDL_sysrwlock_c.h"
+
+/* If two implementations are to be compiled into SDL (the active one
+ * will be chosen at runtime), the function names need to be
+ * suffixed
+ */
+/* !!! FIXME: this is quite a tapdance with macros and the build system, maybe we can simplify how we do this. --ryan. */
+#ifndef SDL_THREAD_GENERIC_RWLOCK_SUFFIX
+#define SDL_CreateRWLock_generic SDL_CreateRWLock
+#define SDL_DestroyRWLock_generic SDL_DestroyRWLock
+#define SDL_LockRWLockForReading_generic SDL_LockRWLockForReading
+#define SDL_LockRWLockForWriting_generic SDL_LockRWLockForWriting
+#define SDL_TryLockRWLockForReading_generic SDL_TryLockRWLockForReading
+#define SDL_TryLockRWLockForWriting_generic SDL_TryLockRWLockForWriting
+#define SDL_UnlockRWLock_generic SDL_UnlockRWLock
+#endif
+
+struct SDL_RWLock
+{
+    SDL_Mutex *lock;
+    SDL_Condition *condition;
+    SDL_threadID writer_thread;
+    SDL_AtomicInt reader_count;
+    SDL_AtomicInt writer_count;
+};
+
+SDL_RWLock *SDL_CreateRWLock_generic(void)
+{
+    SDL_RWLock *rwlock = (SDL_RWLock *) SDL_malloc(sizeof (*rwlock));
+
+    if (!rwlock) {
+        SDL_OutOfMemory();
+        return NULL;
+    }
+
+    rwlock->lock = SDL_CreateMutex();
+    if (!rwlock->lock) {
+        SDL_free(rwlock);
+        return NULL;
+    }
+
+    rwlock->condition = SDL_CreateCondition();
+    if (!rwlock->condition) {
+        SDL_DestroyMutex(rwlock->lock);
+        SDL_free(rwlock);
+        return NULL;
+    }
+
+    SDL_AtomicSet(&rwlock->reader_count, 0);
+    SDL_AtomicSet(&rwlock->writer_count, 0);
+
+    return rwlock;
+}
+
+void SDL_DestroyRWLock_generic(SDL_RWLock *rwlock)
+{
+    if (rwlock) {
+        SDL_DestroyMutex(rwlock->lock);
+        SDL_DestroyCondition(rwlock->condition);
+        SDL_free(rwlock);
+    }
+}
+
+int SDL_LockRWLockForReading_generic(SDL_RWLock *rwlock) SDL_NO_THREAD_SAFETY_ANALYSIS /* clang doesn't know about NULL mutexes */
+{
+    if (!rwlock) {
+        return SDL_InvalidParamError("rwlock");
+    } else if (SDL_LockMutex(rwlock->lock) == -1) {
+        return -1;
+    }
+
+    SDL_assert(SDL_AtomicGet(&rwlock->writer_count) == 0);  /* shouldn't be able to grab lock if there's a writer! */
+
+    SDL_AtomicAdd(&rwlock->reader_count, 1);
+    SDL_UnlockMutex(rwlock->lock);   /* other readers can attempt to share the lock. */
+    return 0;
+}
+
+int SDL_LockRWLockForWriting_generic(SDL_RWLock *rwlock) SDL_NO_THREAD_SAFETY_ANALYSIS /* clang doesn't know about NULL mutexes */
+{
+    if (!rwlock) {
+        return SDL_InvalidParamError("rwlock");
+    } else if (SDL_LockMutex(rwlock->lock) == -1) {
+        return -1;
+    }
+
+    while (SDL_AtomicGet(&rwlock->reader_count) > 0) {  /* while something is holding the shared lock, keep waiting. */
+        SDL_WaitCondition(rwlock->condition, rwlock->lock);  /* release the lock and wait for readers holding the shared lock to release it, regrab the lock. */
+    }
+
+    /* we hold the lock! */
+    SDL_AtomicAdd(&rwlock->writer_count, 1);  /* we let these be recursive, but the API doesn't require this. It _does_ trust you unlock correctly! */
+
+    return 0;
+}
+
+int SDL_TryLockRWLockForReading_generic(SDL_RWLock *rwlock)
+{
+    int rc;
+
+    if (!rwlock) {
+        return SDL_InvalidParamError("rwlock");
+    }
+
+    rc = SDL_TryLockMutex(rwlock->lock);
+    if (rc != 0) {
+        /* !!! FIXME: there is a small window where a reader has to lock the mutex, and if we hit that, we will return SDL_RWLOCK_TIMEDOUT even though we could have shared the lock. */
+        return rc;
+    }
+
+    SDL_assert(SDL_AtomicGet(&rwlock->writer_count) == 0);  /* shouldn't be able to grab lock if there's a writer! */
+
+    SDL_AtomicAdd(&rwlock->reader_count, 1);
+    SDL_UnlockMutex(rwlock->lock);   /* other readers can attempt to share the lock. */
+    return 0;
+}
+
+int SDL_TryLockRWLockForWriting_generic(SDL_RWLock *rwlock)
+{
+    int rc;
+
+    if (!rwlock) {
+        return SDL_InvalidParamError("rwlock");
+    } else if ((rc = SDL_TryLockMutex(rwlock->lock)) != 0) {
+        return rc;
+    }
+
+    if (SDL_AtomicGet(&rwlock->reader_count) > 0) {  /* a reader is using the shared lock, treat it as unavailable. */
+        SDL_UnlockMutex(rwlock->lock);
+        return SDL_RWLOCK_TIMEDOUT;
+    }
+
+    /* we hold the lock! */
+    SDL_AtomicAdd(&rwlock->writer_count, 1);  /* we let these be recursive, but the API doesn't require this. It _does_ trust you unlock correctly! */
+
+    return 0;
+}
+
+int SDL_UnlockRWLock_generic(SDL_RWLock *rwlock) SDL_NO_THREAD_SAFETY_ANALYSIS /* clang doesn't know about NULL mutexes */
+{
+    if (!rwlock) {
+        return SDL_InvalidParamError("rwlock");
+    }
+
+    SDL_LockMutex(rwlock->lock);  /* recursive lock for writers, readers grab lock to make sure things are sane. */
+
+    if (SDL_AtomicGet(&rwlock->reader_count) > 0) {  /* we're a reader */
+        SDL_AtomicAdd(&rwlock->reader_count, -1);
+        SDL_BroadcastCondition(rwlock->condition);  /* alert any pending writers to attempt to try to grab the lock again. */
+    } else if (SDL_AtomicGet(&rwlock->writer_count) > 0) {  /* we're a writer */
+        SDL_AtomicAdd(&rwlock->writer_count, -1);
+        SDL_UnlockMutex(rwlock->lock);  /* recursive unlock. */
+    }
+
+    SDL_UnlockMutex(rwlock->lock);
+
+    return 0;
+}
+

external/sdl/SDL/src/thread/generic/SDL_sysrwlock_c.h

@@ -0,0 +1,38 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2023 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"
+
+#ifndef SDL_sysrwlock_c_h_
+#define SDL_sysrwlock_c_h_
+
+#ifdef SDL_THREAD_GENERIC_RWLOCK_SUFFIX
+
+SDL_RWLock *SDL_CreateRWLock_generic(void);
+void SDL_DestroyRWLock_generic(SDL_RWLock *rwlock);
+int SDL_LockRWLockForReading_generic(SDL_RWLock *rwlock);
+int SDL_LockRWLockForWriting_generic(SDL_RWLock *rwlock);
+int SDL_TryLockRWLockForReading_generic(SDL_RWLock *rwlock);
+int SDL_TryLockRWLockForWriting_generic(SDL_RWLock *rwlock);
+int SDL_UnlockRWLock_generic(SDL_RWLock *rwlock);
+
+#endif /* SDL_THREAD_GENERIC_RWLOCK_SUFFIX */
+
+#endif /* SDL_sysrwlock_c_h_ */

external/sdl/SDL/src/thread/generic/SDL_syssem.c

@@ -0,0 +1,173 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2023 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"
+
+/* An implementation of semaphores using mutexes and condition variables */
+
+#include "SDL_systhread_c.h"
+
+#ifdef SDL_THREADS_DISABLED
+
+SDL_Semaphore *SDL_CreateSemaphore(Uint32 initial_value)
+{
+    SDL_SetError("SDL not built with thread support");
+    return (SDL_Semaphore *)0;
+}
+
+void SDL_DestroySemaphore(SDL_Semaphore *sem)
+{
+}
+
+int SDL_WaitSemaphoreTimeoutNS(SDL_Semaphore *sem, Sint64 timeoutNS)
+{
+    return SDL_SetError("SDL not built with thread support");
+}
+
+Uint32 SDL_GetSemaphoreValue(SDL_Semaphore *sem)
+{
+    return 0;
+}
+
+int SDL_PostSemaphore(SDL_Semaphore *sem)
+{
+    return SDL_SetError("SDL not built with thread support");
+}
+
+#else
+
+struct SDL_Semaphore
+{
+    Uint32 count;
+    Uint32 waiters_count;
+    SDL_Mutex *count_lock;
+    SDL_Condition *count_nonzero;
+};
+
+SDL_Semaphore *SDL_CreateSemaphore(Uint32 initial_value)
+{
+    SDL_Semaphore *sem;
+
+    sem = (SDL_Semaphore *)SDL_malloc(sizeof(*sem));
+    if (sem == NULL) {
+        SDL_OutOfMemory();
+        return NULL;
+    }
+    sem->count = initial_value;
+    sem->waiters_count = 0;
+
+    sem->count_lock = SDL_CreateMutex();
+    sem->count_nonzero = SDL_CreateCondition();
+    if (!sem->count_lock || !sem->count_nonzero) {
+        SDL_DestroySemaphore(sem);
+        return NULL;
+    }
+
+    return sem;
+}
+
+/* WARNING:
+   You cannot call this function when another thread is using the semaphore.
+*/
+void SDL_DestroySemaphore(SDL_Semaphore *sem)
+{
+    if (sem) {
+        sem->count = 0xFFFFFFFF;
+        while (sem->waiters_count > 0) {
+            SDL_SignalCondition(sem->count_nonzero);
+            SDL_Delay(10);
+        }
+        SDL_DestroyCondition(sem->count_nonzero);
+        if (sem->count_lock) {
+            SDL_LockMutex(sem->count_lock);
+            SDL_UnlockMutex(sem->count_lock);
+            SDL_DestroyMutex(sem->count_lock);
+        }
+        SDL_free(sem);
+    }
+}
+
+int SDL_WaitSemaphoreTimeoutNS(SDL_Semaphore *sem, Sint64 timeoutNS)
+{
+    int retval;
+
+    if (sem == NULL) {
+        return SDL_InvalidParamError("sem");
+    }
+
+    /* A timeout of 0 is an easy case */
+    if (timeoutNS == 0) {
+        retval = SDL_MUTEX_TIMEDOUT;
+        SDL_LockMutex(sem->count_lock);
+        if (sem->count > 0) {
+            --sem->count;
+            retval = 0;
+        }
+        SDL_UnlockMutex(sem->count_lock);
+
+        return retval;
+    }
+
+    SDL_LockMutex(sem->count_lock);
+    ++sem->waiters_count;
+    retval = 0;
+    while ((sem->count == 0) && (retval != SDL_MUTEX_TIMEDOUT)) {
+        retval = SDL_WaitConditionTimeoutNS(sem->count_nonzero,
+                                     sem->count_lock, timeoutNS);
+    }
+    --sem->waiters_count;
+    if (retval == 0) {
+        --sem->count;
+    }
+    SDL_UnlockMutex(sem->count_lock);
+
+    return retval;
+}
+
+Uint32 SDL_GetSemaphoreValue(SDL_Semaphore *sem)
+{
+    Uint32 value;
+
+    value = 0;
+    if (sem) {
+        SDL_LockMutex(sem->count_lock);
+        value = sem->count;
+        SDL_UnlockMutex(sem->count_lock);
+    }
+    return value;
+}
+
+int SDL_PostSemaphore(SDL_Semaphore *sem)
+{
+    if (sem == NULL) {
+        return SDL_InvalidParamError("sem");
+    }
+
+    SDL_LockMutex(sem->count_lock);
+    if (sem->waiters_count > 0) {
+        SDL_SignalCondition(sem->count_nonzero);
+    }
+    ++sem->count;
+    SDL_UnlockMutex(sem->count_lock);
+
+    return 0;
+}
+
+#endif /* SDL_THREADS_DISABLED */

external/sdl/SDL/src/thread/generic/SDL_systhread.c

@@ -0,0 +1,61 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2023 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"
+
+/* Thread management routines for SDL */
+
+#include "../SDL_systhread.h"
+
+#ifdef SDL_PASSED_BEGINTHREAD_ENDTHREAD
+int SDL_SYS_CreateThread(SDL_Thread *thread,
+                         pfnSDL_CurrentBeginThread pfnBeginThread,
+                         pfnSDL_CurrentEndThread pfnEndThread)
+#else
+int SDL_SYS_CreateThread(SDL_Thread *thread)
+#endif /* SDL_PASSED_BEGINTHREAD_ENDTHREAD */
+{
+    return SDL_SetError("Threads are not supported on this platform");
+}
+
+void SDL_SYS_SetupThread(const char *name)
+{
+    return;
+}
+
+SDL_threadID SDL_ThreadID(void)
+{
+    return 0;
+}
+
+int SDL_SYS_SetThreadPriority(SDL_ThreadPriority priority)
+{
+    return 0;
+}
+
+void SDL_SYS_WaitThread(SDL_Thread *thread)
+{
+    return;
+}
+
+void SDL_SYS_DetachThread(SDL_Thread *thread)
+{
+    return;
+}

external/sdl/SDL/src/thread/generic/SDL_systhread_c.h

@@ -0,0 +1,24 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2023 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"
+
+/* Stub until we implement threads on this platform */
+typedef int SYS_ThreadHandle;

external/sdl/SDL/src/thread/generic/SDL_systls.c

@@ -0,0 +1,33 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2023 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_thread_c.h"
+
+SDL_TLSData *SDL_SYS_GetTLSData(void)
+{
+    return SDL_Generic_GetTLSData();
+}
+
+int SDL_SYS_SetTLSData(SDL_TLSData *data)
+{
+    return SDL_Generic_SetTLSData(data);
+}