1 /*
2 SDL - Simple DirectMedia Layer
3 Copyright (C) 1997-2006 Sam Lantinga
4
5 This library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 This library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with this library; if not, write to the Free Software
17 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
18
19 Sam Lantinga
20 slouken@libsdl.org
21 */
22 #include "SDL_config.h"
23
24 /* Mutex functions using the Win32 API */
25
26 #define WIN32_LEAN_AND_MEAN
27 #include <windows.h>
28
29 #include "SDL_mutex.h"
30
31
32 struct SDL_mutex {
33 HANDLE id;
34 };
35
36 /* Create a mutex */
SDL_CreateMutex(void)37 SDL_mutex *SDL_CreateMutex(void)
38 {
39 SDL_mutex *mutex;
40
41 /* Allocate mutex memory */
42 mutex = (SDL_mutex *)SDL_malloc(sizeof(*mutex));
43 if ( mutex ) {
44 /* Create the mutex, with initial value signaled */
45 mutex->id = CreateMutex(NULL, FALSE, NULL);
46 if ( ! mutex->id ) {
47 SDL_SetError("Couldn't create mutex");
48 SDL_free(mutex);
49 mutex = NULL;
50 }
51 } else {
52 SDL_OutOfMemory();
53 }
54 return(mutex);
55 }
56
57 /* Free the mutex */
SDL_DestroyMutex(SDL_mutex * mutex)58 void SDL_DestroyMutex(SDL_mutex *mutex)
59 {
60 if ( mutex ) {
61 if ( mutex->id ) {
62 CloseHandle(mutex->id);
63 mutex->id = 0;
64 }
65 SDL_free(mutex);
66 }
67 }
68
69 /* Lock the mutex */
SDL_mutexP(SDL_mutex * mutex)70 int SDL_mutexP(SDL_mutex *mutex)
71 {
72 if ( mutex == NULL ) {
73 SDL_SetError("Passed a NULL mutex");
74 return -1;
75 }
76 if ( WaitForSingleObject(mutex->id, INFINITE) == WAIT_FAILED ) {
77 SDL_SetError("Couldn't wait on mutex");
78 return -1;
79 }
80 return(0);
81 }
82
83 /* Unlock the mutex */
SDL_mutexV(SDL_mutex * mutex)84 int SDL_mutexV(SDL_mutex *mutex)
85 {
86 if ( mutex == NULL ) {
87 SDL_SetError("Passed a NULL mutex");
88 return -1;
89 }
90 if ( ReleaseMutex(mutex->id) == FALSE ) {
91 SDL_SetError("Couldn't release mutex");
92 return -1;
93 }
94 return(0);
95 }
96