diff options
Diffstat (limited to 'distrib/sdl-1.2.15/src/thread/win32/SDL_syssem.c')
| -rw-r--r-- | distrib/sdl-1.2.15/src/thread/win32/SDL_syssem.c | 164 |
1 files changed, 164 insertions, 0 deletions
diff --git a/distrib/sdl-1.2.15/src/thread/win32/SDL_syssem.c b/distrib/sdl-1.2.15/src/thread/win32/SDL_syssem.c new file mode 100644 index 0000000..261d24c --- /dev/null +++ b/distrib/sdl-1.2.15/src/thread/win32/SDL_syssem.c @@ -0,0 +1,164 @@ +/* + 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" + +/* Semaphore functions using the Win32 API */ + +#define WIN32_LEAN_AND_MEAN +#include <windows.h> + +#include "SDL_thread.h" +#if defined(_WIN32_WCE) && (_WIN32_WCE < 300) +#include "win_ce_semaphore.h" +#endif + + +struct SDL_semaphore { +#if defined(_WIN32_WCE) && (_WIN32_WCE < 300) + SYNCHHANDLE id; +#else + HANDLE id; +#endif + volatile LONG count; +}; + + +/* Create a semaphore */ +SDL_sem *SDL_CreateSemaphore(Uint32 initial_value) +{ + SDL_sem *sem; + + /* Allocate sem memory */ + sem = (SDL_sem *)SDL_malloc(sizeof(*sem)); + if ( sem ) { + /* Create the semaphore, with max value 32K */ +#if defined(_WIN32_WCE) && (_WIN32_WCE < 300) + sem->id = CreateSemaphoreCE(NULL, initial_value, 32*1024, NULL); +#else + sem->id = CreateSemaphore(NULL, initial_value, 32*1024, NULL); +#endif + sem->count = (LONG) initial_value; + if ( ! sem->id ) { + SDL_SetError("Couldn't create semaphore"); + SDL_free(sem); + sem = NULL; + } + } else { + SDL_OutOfMemory(); + } + return(sem); +} + +/* Free the semaphore */ +void SDL_DestroySemaphore(SDL_sem *sem) +{ + if ( sem ) { + if ( sem->id ) { +#if defined(_WIN32_WCE) && (_WIN32_WCE < 300) + CloseSynchHandle(sem->id); +#else + CloseHandle(sem->id); +#endif + sem->id = 0; + } + SDL_free(sem); + } +} + +int SDL_SemWaitTimeout(SDL_sem *sem, Uint32 timeout) +{ + int retval; + DWORD dwMilliseconds; + + if ( ! sem ) { + SDL_SetError("Passed a NULL sem"); + return -1; + } + + if ( timeout == SDL_MUTEX_MAXWAIT ) { + dwMilliseconds = INFINITE; + } else { + dwMilliseconds = (DWORD)timeout; + } +#if defined(_WIN32_WCE) && (_WIN32_WCE < 300) + switch (WaitForSemaphoreCE(sem->id, dwMilliseconds)) { +#else + switch (WaitForSingleObject(sem->id, dwMilliseconds)) { +#endif + case WAIT_OBJECT_0: + InterlockedDecrement(&sem->count); + retval = 0; + break; + case WAIT_TIMEOUT: + retval = SDL_MUTEX_TIMEDOUT; + break; + default: + SDL_SetError("WaitForSingleObject() failed"); + retval = -1; + break; + } + return retval; +} + +int SDL_SemTryWait(SDL_sem *sem) +{ + return SDL_SemWaitTimeout(sem, 0); +} + +int SDL_SemWait(SDL_sem *sem) +{ + return SDL_SemWaitTimeout(sem, SDL_MUTEX_MAXWAIT); +} + +/* Returns the current count of the semaphore */ +Uint32 SDL_SemValue(SDL_sem *sem) +{ + if ( ! sem ) { + SDL_SetError("Passed a NULL sem"); + return 0; + } + return (Uint32) sem->count; +} + +int SDL_SemPost(SDL_sem *sem) +{ + if ( ! sem ) { + SDL_SetError("Passed a NULL sem"); + return -1; + } + /* Increase the counter in the first place, because + * after a successful release the semaphore may + * immediately get destroyed by another thread which + * is waiting for this semaphore. + */ + InterlockedIncrement(&sem->count); +#if defined(_WIN32_WCE) && (_WIN32_WCE < 300) + if ( ReleaseSemaphoreCE(sem->id, 1, NULL) == FALSE ) { +#else + if ( ReleaseSemaphore(sem->id, 1, NULL) == FALSE ) { +#endif + InterlockedDecrement(&sem->count); /* restore */ + SDL_SetError("ReleaseSemaphore() failed"); + return -1; + } + return 0; +} |