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Diffstat (limited to '3rdparty/SDL2/src/thread/pthread/SDL_sysmutex.c')
-rw-r--r--3rdparty/SDL2/src/thread/pthread/SDL_sysmutex.c195
1 files changed, 195 insertions, 0 deletions
diff --git a/3rdparty/SDL2/src/thread/pthread/SDL_sysmutex.c b/3rdparty/SDL2/src/thread/pthread/SDL_sysmutex.c
new file mode 100644
index 00000000000..f24cfdab01e
--- /dev/null
+++ b/3rdparty/SDL2/src/thread/pthread/SDL_sysmutex.c
@@ -0,0 +1,195 @@
+/*
+ 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"
+
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
+#include <errno.h>
+#include <pthread.h>
+
+#include "SDL_thread.h"
+
+#if !SDL_THREAD_PTHREAD_RECURSIVE_MUTEX && \
+ !SDL_THREAD_PTHREAD_RECURSIVE_MUTEX_NP
+#define FAKE_RECURSIVE_MUTEX 1
+#endif
+
+struct SDL_mutex
+{
+ pthread_mutex_t id;
+#if FAKE_RECURSIVE_MUTEX
+ int recursive;
+ pthread_t owner;
+#endif
+};
+
+SDL_mutex *
+SDL_CreateMutex(void)
+{
+ SDL_mutex *mutex;
+ pthread_mutexattr_t attr;
+
+ /* Allocate the structure */
+ mutex = (SDL_mutex *) SDL_calloc(1, sizeof(*mutex));
+ if (mutex) {
+ pthread_mutexattr_init(&attr);
+#if SDL_THREAD_PTHREAD_RECURSIVE_MUTEX
+ pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE);
+#elif SDL_THREAD_PTHREAD_RECURSIVE_MUTEX_NP
+ pthread_mutexattr_setkind_np(&attr, PTHREAD_MUTEX_RECURSIVE_NP);
+#else
+ /* No extra attributes necessary */
+#endif
+ if (pthread_mutex_init(&mutex->id, &attr) != 0) {
+ SDL_SetError("pthread_mutex_init() failed");
+ SDL_free(mutex);
+ mutex = NULL;
+ }
+ } else {
+ SDL_OutOfMemory();
+ }
+ return (mutex);
+}
+
+void
+SDL_DestroyMutex(SDL_mutex * mutex)
+{
+ if (mutex) {
+ pthread_mutex_destroy(&mutex->id);
+ SDL_free(mutex);
+ }
+}
+
+/* Lock the mutex */
+int
+SDL_LockMutex(SDL_mutex * mutex)
+{
+#if FAKE_RECURSIVE_MUTEX
+ pthread_t this_thread;
+#endif
+
+ if (mutex == NULL) {
+ return SDL_SetError("Passed a NULL mutex");
+ }
+
+#if FAKE_RECURSIVE_MUTEX
+ this_thread = pthread_self();
+ 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.
+ */
+ if (pthread_mutex_lock(&mutex->id) == 0) {
+ mutex->owner = this_thread;
+ mutex->recursive = 0;
+ } else {
+ return SDL_SetError("pthread_mutex_lock() failed");
+ }
+ }
+#else
+ if (pthread_mutex_lock(&mutex->id) < 0) {
+ return SDL_SetError("pthread_mutex_lock() failed");
+ }
+#endif
+ return 0;
+}
+
+int
+SDL_TryLockMutex(SDL_mutex * mutex)
+{
+ int retval;
+#if FAKE_RECURSIVE_MUTEX
+ pthread_t this_thread;
+#endif
+
+ if (mutex == NULL) {
+ return SDL_SetError("Passed a NULL mutex");
+ }
+
+ retval = 0;
+#if FAKE_RECURSIVE_MUTEX
+ this_thread = pthread_self();
+ 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.
+ */
+ if (pthread_mutex_lock(&mutex->id) == 0) {
+ mutex->owner = this_thread;
+ mutex->recursive = 0;
+ } else if (errno == EBUSY) {
+ retval = SDL_MUTEX_TIMEDOUT;
+ } else {
+ retval = SDL_SetError("pthread_mutex_trylock() failed");
+ }
+ }
+#else
+ if (pthread_mutex_trylock(&mutex->id) != 0) {
+ if (errno == EBUSY) {
+ retval = SDL_MUTEX_TIMEDOUT;
+ } else {
+ retval = SDL_SetError("pthread_mutex_trylock() failed");
+ }
+ }
+#endif
+ return retval;
+}
+
+int
+SDL_UnlockMutex(SDL_mutex * mutex)
+{
+ if (mutex == NULL) {
+ return SDL_SetError("Passed a NULL mutex");
+ }
+
+#if FAKE_RECURSIVE_MUTEX
+ /* We can only unlock the mutex if we own it */
+ if (pthread_self() == mutex->owner) {
+ 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;
+ pthread_mutex_unlock(&mutex->id);
+ }
+ } else {
+ return SDL_SetError("mutex not owned by this thread");
+ }
+
+#else
+ if (pthread_mutex_unlock(&mutex->id) < 0) {
+ return SDL_SetError("pthread_mutex_unlock() failed");
+ }
+#endif /* FAKE_RECURSIVE_MUTEX */
+
+ return 0;
+}
+
+/* vi: set ts=4 sw=4 expandtab: */