symbian-qemu-0.9.1-12/libsdl-trunk/src/thread/dc/SDL_syssem.c
changeset 1 2fb8b9db1c86
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/symbian-qemu-0.9.1-12/libsdl-trunk/src/thread/dc/SDL_syssem.c	Fri Jul 31 15:01:17 2009 +0100
@@ -0,0 +1,173 @@
+/*
+    SDL - Simple DirectMedia Layer
+    Copyright (C) 1997-2006 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 <errno.h>
+
+#include "SDL_config.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 configured with thread support");
+	return (SDL_sem *)0;
+}
+
+void SDL_DestroySemaphore(SDL_sem *sem)
+{
+	return;
+}
+
+int SDL_SemTryWait(SDL_sem *sem)
+{
+	SDL_SetError("SDL not configured with thread support");
+	return -1;
+}
+
+int SDL_SemWaitTimeout(SDL_sem *sem, Uint32 timeout)
+{
+	SDL_SetError("SDL not configured with thread support");
+	return -1;
+}
+
+int SDL_SemWait(SDL_sem *sem)
+{
+	SDL_SetError("SDL not configured with thread support");
+	return -1;
+}
+
+Uint32 SDL_SemValue(SDL_sem *sem)
+{
+	return 0;
+}
+
+int SDL_SemPost(SDL_sem *sem)
+{
+	SDL_SetError("SDL not configured with thread support");
+	return -1;
+}
+
+#else
+
+#include <kos/sem.h>
+
+struct SDL_semaphore
+{
+	semaphore_t sem;
+};
+
+SDL_sem *SDL_CreateSemaphore(Uint32 initial_value)
+{
+	return (SDL_sem *)sem_create(initial_value);
+}
+
+/* WARNING:
+   You cannot call this function when another thread is using the semaphore.
+*/
+void SDL_DestroySemaphore(SDL_sem *sem)
+{
+	if ( ! sem ) {
+		SDL_SetError("Passed a NULL semaphore");
+		return;
+	}
+
+	sem_destroy(&sem->sem);
+}
+
+int SDL_SemTryWait(SDL_sem *sem)
+{
+	int retval;
+
+	if ( ! sem ) {
+		SDL_SetError("Passed a NULL semaphore");
+		return -1;
+	}
+
+	retval = sem_trywait(&sem->sem);
+	if (retval==0) return 0;
+	else return SDL_MUTEX_TIMEDOUT;
+
+	return retval;
+}
+
+int SDL_SemWaitTimeout(SDL_sem *sem, Uint32 timeout)
+{
+	int retval;
+
+	if ( ! sem ) {
+		SDL_SetError("Passed a NULL semaphore");
+		return -1;
+	}
+
+	/* A timeout of 0 is an easy case */
+	if ( timeout == 0 ) {
+		return SDL_SemTryWait(sem);
+	}
+
+	retval = sem_wait_timed(&sem->sem,timeout);
+	if (retval==-1) retval= SDL_MUTEX_TIMEDOUT;
+
+	return retval;
+}
+
+int SDL_SemWait(SDL_sem *sem)
+{
+	int retval;
+
+	if ( ! sem ) {
+		SDL_SetError("Passed a NULL semaphore");
+		return -1;
+	}
+
+	while ( ((retval = sem_wait(&sem->sem)) == -1) && (errno == EINTR) ) {}
+	return retval;
+}
+
+Uint32 SDL_SemValue(SDL_sem *sem)
+{
+	if ( ! sem ) {
+		SDL_SetError("Passed a NULL semaphore");
+		return -1;
+	}
+
+	return sem_count(&sem->sem);
+}
+
+int SDL_SemPost(SDL_sem *sem)
+{
+	if ( ! sem ) {
+		SDL_SetError("Passed a NULL semaphore");
+		return -1;
+	}
+
+	sem_signal(&sem->sem);
+	return 0;
+}
+
+#endif /* SDL_THREADS_DISABLED */