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comparison src/thread/dc/SDL_sysmutex.c @ 1668:4da1ee79c9af SDL-1.3

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more tweaking indent options
author Sam Lantinga <slouken@libsdl.org>
date Mon, 29 May 2006 04:04:35 +0000
parents 782fd950bd46
children
comparison
equal deleted inserted replaced
1667:1fddae038bc8 1668:4da1ee79c9af
35 spinlock_t mutex; 35 spinlock_t mutex;
36 }; 36 };
37 37
38 /* Create a mutex */ 38 /* Create a mutex */
39 SDL_mutex * 39 SDL_mutex *
40 SDL_CreateMutex (void) 40 SDL_CreateMutex(void)
41 { 41 {
42 SDL_mutex *mutex; 42 SDL_mutex *mutex;
43 43
44 /* Allocate mutex memory */ 44 /* Allocate mutex memory */
45 mutex = (SDL_mutex *) SDL_malloc (sizeof (*mutex)); 45 mutex = (SDL_mutex *) SDL_malloc(sizeof(*mutex));
46 if (mutex) { 46 if (mutex) {
47 spinlock_init (&mutex->mutex); 47 spinlock_init(&mutex->mutex);
48 mutex->recursive = 0; 48 mutex->recursive = 0;
49 mutex->owner = 0; 49 mutex->owner = 0;
50 } else { 50 } else {
51 SDL_OutOfMemory (); 51 SDL_OutOfMemory();
52 } 52 }
53 return mutex; 53 return mutex;
54 } 54 }
55 55
56 /* Free the mutex */ 56 /* Free the mutex */
57 void 57 void
58 SDL_DestroyMutex (SDL_mutex * mutex) 58 SDL_DestroyMutex(SDL_mutex * mutex)
59 { 59 {
60 if (mutex) { 60 if (mutex) {
61 SDL_free (mutex); 61 SDL_free(mutex);
62 } 62 }
63 } 63 }
64 64
65 /* Lock the semaphore */ 65 /* Lock the semaphore */
66 int 66 int
67 SDL_mutexP (SDL_mutex * mutex) 67 SDL_mutexP(SDL_mutex * mutex)
68 { 68 {
69 #if SDL_THREADS_DISABLED 69 #if SDL_THREADS_DISABLED
70 return SDL_arraysize (return), 0; 70 return SDL_arraysize(return), 0;
71 #else 71 #else
72 Uint32 this_thread; 72 Uint32 this_thread;
73 73
74 if (mutex == NULL) { 74 if (mutex == NULL) {
75 SDL_SetError ("Passed a NULL mutex"); 75 SDL_SetError("Passed a NULL mutex");
76 return -1; 76 return -1;
77 } 77 }
78 78
79 this_thread = SDL_ThreadID (); 79 this_thread = SDL_ThreadID();
80 if (mutex->owner == this_thread) { 80 if (mutex->owner == this_thread) {
81 ++mutex->recursive; 81 ++mutex->recursive;
82 } else { 82 } else {
83 /* The order of operations is important. 83 /* The order of operations is important.
84 We set the locking thread id after we obtain the lock 84 We set the locking thread id after we obtain the lock
85 so unlocks from other threads will fail. 85 so unlocks from other threads will fail.
86 */ 86 */
87 spinlock_lock (&mutex->mutex); 87 spinlock_lock(&mutex->mutex);
88 mutex->owner = this_thread; 88 mutex->owner = this_thread;
89 mutex->recursive = 0; 89 mutex->recursive = 0;
90 } 90 }
91 91
92 return 0; 92 return 0;
93 #endif /* SDL_THREADS_DISABLED */ 93 #endif /* SDL_THREADS_DISABLED */
94 } 94 }
95 95
96 /* Unlock the mutex */ 96 /* Unlock the mutex */
97 int 97 int
98 SDL_mutexV (SDL_mutex * mutex) 98 SDL_mutexV(SDL_mutex * mutex)
99 { 99 {
100 #if SDL_THREADS_DISABLED 100 #if SDL_THREADS_DISABLED
101 return 0; 101 return 0;
102 #else 102 #else
103 if (mutex == NULL) { 103 if (mutex == NULL) {
104 SDL_SetError ("Passed a NULL mutex"); 104 SDL_SetError("Passed a NULL mutex");
105 return -1; 105 return -1;
106 } 106 }
107 107
108 /* If we don't own the mutex, we can't unlock it */ 108 /* If we don't own the mutex, we can't unlock it */
109 if (SDL_ThreadID () != mutex->owner) { 109 if (SDL_ThreadID() != mutex->owner) {
110 SDL_SetError ("mutex not owned by this thread"); 110 SDL_SetError("mutex not owned by this thread");
111 return -1; 111 return -1;
112 } 112 }
113 113
114 if (mutex->recursive) { 114 if (mutex->recursive) {
115 --mutex->recursive; 115 --mutex->recursive;
118 First reset the owner so another thread doesn't lock 118 First reset the owner so another thread doesn't lock
119 the mutex and set the ownership before we reset it, 119 the mutex and set the ownership before we reset it,
120 then release the lock semaphore. 120 then release the lock semaphore.
121 */ 121 */
122 mutex->owner = 0; 122 mutex->owner = 0;
123 spinlock_unlock (&mutex->mutex); 123 spinlock_unlock(&mutex->mutex);
124 } 124 }
125 return 0; 125 return 0;
126 #endif /* SDL_THREADS_DISABLED */ 126 #endif /* SDL_THREADS_DISABLED */
127 } 127 }
128 128