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diff --git a/distrib/sdl-1.2.15/src/thread/dc/SDL_syscond.c b/distrib/sdl-1.2.15/src/thread/dc/SDL_syscond.c
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+++ b/distrib/sdl-1.2.15/src/thread/dc/SDL_syscond.c
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+/*
+ 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"
+
+/* 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 "SDL_thread.h"
+
+struct SDL_cond
+{
+ SDL_mutex *lock;
+ int waiting;
+ int signals;
+ SDL_sem *wait_sem;
+ SDL_sem *wait_done;
+};
+
+/* Create a condition variable */
+SDL_cond * SDL_CreateCond(void)
+{
+ SDL_cond *cond;
+
+ cond = (SDL_cond *) SDL_malloc(sizeof(SDL_cond));
+ 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_DestroyCond(cond);
+ cond = NULL;
+ }
+ } else {
+ SDL_OutOfMemory();
+ }
+ return(cond);
+}
+
+/* Destroy a condition variable */
+void SDL_DestroyCond(SDL_cond *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_CondSignal(SDL_cond *cond)
+{
+ if ( ! cond ) {
+ SDL_SetError("Passed a NULL condition variable");
+ return -1;
+ }
+
+ /* 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_SemPost(cond->wait_sem);
+ SDL_UnlockMutex(cond->lock);
+ SDL_SemWait(cond->wait_done);
+ } else {
+ SDL_UnlockMutex(cond->lock);
+ }
+
+ return 0;
+}
+
+/* Restart all threads that are waiting on the condition variable */
+int SDL_CondBroadcast(SDL_cond *cond)
+{
+ if ( ! cond ) {
+ SDL_SetError("Passed a NULL condition variable");
+ return -1;
+ }
+
+ /* 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_SemPost(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_SemWait(cond->wait_done);
+ }
+ } else {
+ SDL_UnlockMutex(cond->lock);
+ }
+
+ return 0;
+}
+
+/* Wait on the condition variable for at most 'ms' milliseconds.
+ 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_CondWait(cond);
+ }
+ SDL_UnlockMutex(lock);
+
+Thread B:
+ SDL_LockMutex(lock);
+ ...
+ condition = true;
+ ...
+ SDL_UnlockMutex(lock);
+ */
+int SDL_CondWaitTimeout(SDL_cond *cond, SDL_mutex *mutex, Uint32 ms)
+{
+ int retval;
+
+ if ( ! cond ) {
+ SDL_SetError("Passed a NULL condition variable");
+ return -1;
+ }
+
+ /* 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 */
+ if ( ms == SDL_MUTEX_MAXWAIT ) {
+ retval = SDL_SemWait(cond->wait_sem);
+ } else {
+ retval = SDL_SemWaitTimeout(cond->wait_sem, ms);
+ }
+
+ /* 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://www-classic.be.com/aboutbe/benewsletter/volume_III/Issue40.html
+ */
+ SDL_LockMutex(cond->lock);
+ if ( cond->signals > 0 ) {
+ /* If we timed out, we need to eat a condition signal */
+ if ( retval > 0 ) {
+ SDL_SemWait(cond->wait_sem);
+ }
+ /* We always notify the signal thread that we are done */
+ SDL_SemPost(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;
+}
+
+/* Wait on the condition variable forever */
+int SDL_CondWait(SDL_cond *cond, SDL_mutex *mutex)
+{
+ return SDL_CondWaitTimeout(cond, mutex, SDL_MUTEX_MAXWAIT);
+}