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Diffstat (limited to 'distrib/sdl-1.2.15/src/thread/pthread/SDL_sysmutex.c')
-rw-r--r--distrib/sdl-1.2.15/src/thread/pthread/SDL_sysmutex.c153
1 files changed, 153 insertions, 0 deletions
diff --git a/distrib/sdl-1.2.15/src/thread/pthread/SDL_sysmutex.c b/distrib/sdl-1.2.15/src/thread/pthread/SDL_sysmutex.c
new file mode 100644
index 0000000..c3b8ce2
--- /dev/null
+++ b/distrib/sdl-1.2.15/src/thread/pthread/SDL_sysmutex.c
@@ -0,0 +1,153 @@
+/*
+ SDL - Simple DirectMedia Layer
+ Copyright (C) 1997-2012 Sam Lantinga
+
+ This library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ This library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with this library; if not, write to the Free Software
+ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+
+ Sam Lantinga
+ slouken@libsdl.org
+*/
+#include "SDL_config.h"
+
+#include <pthread.h>
+
+#include "SDL_thread.h"
+
+#if !SDL_THREAD_PTHREAD_RECURSIVE_MUTEX && \
+ !SDL_THREAD_PTHREAD_RECURSIVE_MUTEX_NP
+#define FAKE_RECURSIVE_MUTEX
+#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_mutexP(SDL_mutex *mutex)
+{
+ int retval;
+#if FAKE_RECURSIVE_MUTEX
+ pthread_t this_thread;
+#endif
+
+ if ( mutex == NULL ) {
+ SDL_SetError("Passed a NULL mutex");
+ return -1;
+ }
+
+ 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 {
+ SDL_SetError("pthread_mutex_lock() failed");
+ retval = -1;
+ }
+ }
+#else
+ if ( pthread_mutex_lock(&mutex->id) < 0 ) {
+ SDL_SetError("pthread_mutex_lock() failed");
+ retval = -1;
+ }
+#endif
+ return retval;
+}
+
+int SDL_mutexV(SDL_mutex *mutex)
+{
+ int retval;
+
+ if ( mutex == NULL ) {
+ SDL_SetError("Passed a NULL mutex");
+ return -1;
+ }
+
+ retval = 0;
+#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 {
+ SDL_SetError("mutex not owned by this thread");
+ retval = -1;
+ }
+
+#else
+ if ( pthread_mutex_unlock(&mutex->id) < 0 ) {
+ SDL_SetError("pthread_mutex_unlock() failed");
+ retval = -1;
+ }
+#endif /* FAKE_RECURSIVE_MUTEX */
+
+ return retval;
+}