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Diffstat (limited to '3rdparty/SDL2/src/thread/generic/SDL_syssem.c')
-rw-r--r--3rdparty/SDL2/src/thread/generic/SDL_syssem.c217
1 files changed, 217 insertions, 0 deletions
diff --git a/3rdparty/SDL2/src/thread/generic/SDL_syssem.c b/3rdparty/SDL2/src/thread/generic/SDL_syssem.c
new file mode 100644
index 00000000000..92afcb0c07f
--- /dev/null
+++ b/3rdparty/SDL2/src/thread/generic/SDL_syssem.c
@@ -0,0 +1,217 @@
+/*
+ Simple DirectMedia Layer
+ Copyright (C) 1997-2016 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_timer.h"
+#include "SDL_thread.h"
+#include "SDL_systhread_c.h"
+
+
+#if SDL_THREADS_DISABLED
+
+SDL_sem *
+SDL_CreateSemaphore(Uint32 initial_value)
+{
+ SDL_SetError("SDL not built with thread support");
+ return (SDL_sem *) 0;
+}
+
+void
+SDL_DestroySemaphore(SDL_sem * sem)
+{
+}
+
+int
+SDL_SemTryWait(SDL_sem * sem)
+{
+ return SDL_SetError("SDL not built with thread support");
+}
+
+int
+SDL_SemWaitTimeout(SDL_sem * sem, Uint32 timeout)
+{
+ return SDL_SetError("SDL not built with thread support");
+}
+
+int
+SDL_SemWait(SDL_sem * sem)
+{
+ return SDL_SetError("SDL not built with thread support");
+}
+
+Uint32
+SDL_SemValue(SDL_sem * sem)
+{
+ return 0;
+}
+
+int
+SDL_SemPost(SDL_sem * sem)
+{
+ return SDL_SetError("SDL not built with thread support");
+}
+
+#else
+
+struct SDL_semaphore
+{
+ Uint32 count;
+ Uint32 waiters_count;
+ SDL_mutex *count_lock;
+ SDL_cond *count_nonzero;
+};
+
+SDL_sem *
+SDL_CreateSemaphore(Uint32 initial_value)
+{
+ SDL_sem *sem;
+
+ sem = (SDL_sem *) SDL_malloc(sizeof(*sem));
+ if (!sem) {
+ SDL_OutOfMemory();
+ return NULL;
+ }
+ sem->count = initial_value;
+ sem->waiters_count = 0;
+
+ sem->count_lock = SDL_CreateMutex();
+ sem->count_nonzero = SDL_CreateCond();
+ 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_sem * sem)
+{
+ if (sem) {
+ sem->count = 0xFFFFFFFF;
+ while (sem->waiters_count > 0) {
+ SDL_CondSignal(sem->count_nonzero);
+ SDL_Delay(10);
+ }
+ SDL_DestroyCond(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_SemTryWait(SDL_sem * sem)
+{
+ int retval;
+
+ if (!sem) {
+ return SDL_SetError("Passed a NULL semaphore");
+ }
+
+ retval = SDL_MUTEX_TIMEDOUT;
+ SDL_LockMutex(sem->count_lock);
+ if (sem->count > 0) {
+ --sem->count;
+ retval = 0;
+ }
+ SDL_UnlockMutex(sem->count_lock);
+
+ return retval;
+}
+
+int
+SDL_SemWaitTimeout(SDL_sem * sem, Uint32 timeout)
+{
+ int retval;
+
+ if (!sem) {
+ return SDL_SetError("Passed a NULL semaphore");
+ }
+
+ /* A timeout of 0 is an easy case */
+ if (timeout == 0) {
+ return SDL_SemTryWait(sem);
+ }
+
+ SDL_LockMutex(sem->count_lock);
+ ++sem->waiters_count;
+ retval = 0;
+ while ((sem->count == 0) && (retval != SDL_MUTEX_TIMEDOUT)) {
+ retval = SDL_CondWaitTimeout(sem->count_nonzero,
+ sem->count_lock, timeout);
+ }
+ --sem->waiters_count;
+ if (retval == 0) {
+ --sem->count;
+ }
+ SDL_UnlockMutex(sem->count_lock);
+
+ return retval;
+}
+
+int
+SDL_SemWait(SDL_sem * sem)
+{
+ return SDL_SemWaitTimeout(sem, SDL_MUTEX_MAXWAIT);
+}
+
+Uint32
+SDL_SemValue(SDL_sem * sem)
+{
+ Uint32 value;
+
+ value = 0;
+ if (sem) {
+ SDL_LockMutex(sem->count_lock);
+ value = sem->count;
+ SDL_UnlockMutex(sem->count_lock);
+ }
+ return value;
+}
+
+int
+SDL_SemPost(SDL_sem * sem)
+{
+ if (!sem) {
+ return SDL_SetError("Passed a NULL semaphore");
+ }
+
+ SDL_LockMutex(sem->count_lock);
+ if (sem->waiters_count > 0) {
+ SDL_CondSignal(sem->count_nonzero);
+ }
+ ++sem->count;
+ SDL_UnlockMutex(sem->count_lock);
+
+ return 0;
+}
+
+#endif /* SDL_THREADS_DISABLED */
+/* vi: set ts=4 sw=4 expandtab: */