src/thread/win32/SDL_sysmutex.c
author Sam Lantinga <slouken@lokigames.com>
Thu, 26 Apr 2001 16:45:43 +0000
changeset 0 74212992fb08
child 252 e8157fcb3114
permissions -rw-r--r--
Initial revision
slouken@0
     1
/*
slouken@0
     2
    SDL - Simple DirectMedia Layer
slouken@0
     3
    Copyright (C) 1997, 1998, 1999, 2000, 2001  Sam Lantinga
slouken@0
     4
slouken@0
     5
    This library is free software; you can redistribute it and/or
slouken@0
     6
    modify it under the terms of the GNU Library General Public
slouken@0
     7
    License as published by the Free Software Foundation; either
slouken@0
     8
    version 2 of the License, or (at your option) any later version.
slouken@0
     9
slouken@0
    10
    This library is distributed in the hope that it will be useful,
slouken@0
    11
    but WITHOUT ANY WARRANTY; without even the implied warranty of
slouken@0
    12
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
slouken@0
    13
    Library General Public License for more details.
slouken@0
    14
slouken@0
    15
    You should have received a copy of the GNU Library General Public
slouken@0
    16
    License along with this library; if not, write to the Free
slouken@0
    17
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
slouken@0
    18
slouken@0
    19
    Sam Lantinga
slouken@0
    20
    slouken@devolution.com
slouken@0
    21
*/
slouken@0
    22
slouken@0
    23
#ifdef SAVE_RCSID
slouken@0
    24
static char rcsid =
slouken@0
    25
 "@(#) $Id$";
slouken@0
    26
#endif
slouken@0
    27
slouken@0
    28
/* Mutex functions using the Win32 API */
slouken@0
    29
slouken@0
    30
#include <stdio.h>
slouken@0
    31
#include <stdlib.h>
slouken@0
    32
#include <windows.h>
slouken@0
    33
slouken@0
    34
#include "SDL_error.h"
slouken@0
    35
#include "SDL_mutex.h"
slouken@0
    36
slouken@0
    37
slouken@0
    38
struct SDL_mutex {
slouken@0
    39
	HANDLE id;
slouken@0
    40
};
slouken@0
    41
slouken@0
    42
/* Create a mutex */
slouken@0
    43
SDL_mutex *SDL_CreateMutex(void)
slouken@0
    44
{
slouken@0
    45
	SDL_mutex *mutex;
slouken@0
    46
slouken@0
    47
	/* Allocate mutex memory */
slouken@0
    48
	mutex = (SDL_mutex *)malloc(sizeof(*mutex));
slouken@0
    49
	if ( mutex ) {
slouken@0
    50
		/* Create the mutex, with initial value signaled */
slouken@0
    51
		mutex->id = CreateMutex(NULL, FALSE, NULL);
slouken@0
    52
		if ( ! mutex->id ) {
slouken@0
    53
			SDL_SetError("Couldn't create mutex");
slouken@0
    54
			free(mutex);
slouken@0
    55
			mutex = NULL;
slouken@0
    56
		}
slouken@0
    57
	} else {
slouken@0
    58
		SDL_OutOfMemory();
slouken@0
    59
	}
slouken@0
    60
	return(mutex);
slouken@0
    61
}
slouken@0
    62
slouken@0
    63
/* Free the mutex */
slouken@0
    64
void SDL_DestroyMutex(SDL_mutex *mutex)
slouken@0
    65
{
slouken@0
    66
	if ( mutex ) {
slouken@0
    67
		if ( mutex->id ) {
slouken@0
    68
			CloseHandle(mutex->id);
slouken@0
    69
			mutex->id = 0;
slouken@0
    70
		}
slouken@0
    71
		free(mutex);
slouken@0
    72
	}
slouken@0
    73
}
slouken@0
    74
slouken@0
    75
/* Lock the mutex */
slouken@0
    76
int SDL_mutexP(SDL_mutex *mutex)
slouken@0
    77
{
slouken@0
    78
	if ( mutex == NULL ) {
slouken@0
    79
		SDL_SetError("Passed a NULL mutex");
slouken@0
    80
		return -1;
slouken@0
    81
	}
slouken@0
    82
	if ( WaitForSingleObject(mutex->id, INFINITE) == WAIT_FAILED ) {
slouken@0
    83
		SDL_SetError("Couldn't wait on mutex");
slouken@0
    84
		return -1;
slouken@0
    85
	}
slouken@0
    86
	return(0);
slouken@0
    87
}
slouken@0
    88
slouken@0
    89
/* Unlock the mutex */
slouken@0
    90
int SDL_mutexV(SDL_mutex *mutex)
slouken@0
    91
{
slouken@0
    92
	if ( mutex == NULL ) {
slouken@0
    93
		SDL_SetError("Passed a NULL mutex");
slouken@0
    94
		return -1;
slouken@0
    95
	}
slouken@0
    96
	if ( ReleaseMutex(mutex->id) == FALSE ) {
slouken@0
    97
		SDL_SetError("Couldn't release mutex");
slouken@0
    98
		return -1;
slouken@0
    99
	}
slouken@0
   100
	return(0);
slouken@0
   101
}