annotate src/thread/dc/SDL_sysmutex.c @ 1338:604d73db6802

Removed uses of stdlib.h and string.h
author Sam Lantinga <slouken@libsdl.org>
date Tue, 07 Feb 2006 09:29:18 +0000
parents 3692456e7b0f
children c71e05b4dc2e
rev   line source
509
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
1 /*
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
2 SDL - Simple DirectMedia Layer
1312
c9b51268668f Updated copyright information and removed rcs id lines (problematic in branch merges)
Sam Lantinga <slouken@libsdl.org>
parents: 769
diff changeset
3 Copyright (C) 1997-2006 Sam Lantinga
509
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
4
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
5 This library is free software; you can redistribute it and/or
1312
c9b51268668f Updated copyright information and removed rcs id lines (problematic in branch merges)
Sam Lantinga <slouken@libsdl.org>
parents: 769
diff changeset
6 modify it under the terms of the GNU Lesser General Public
509
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
7 License as published by the Free Software Foundation; either
1312
c9b51268668f Updated copyright information and removed rcs id lines (problematic in branch merges)
Sam Lantinga <slouken@libsdl.org>
parents: 769
diff changeset
8 version 2.1 of the License, or (at your option) any later version.
509
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
9
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
10 This library is distributed in the hope that it will be useful,
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
1312
c9b51268668f Updated copyright information and removed rcs id lines (problematic in branch merges)
Sam Lantinga <slouken@libsdl.org>
parents: 769
diff changeset
13 Lesser General Public License for more details.
509
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
14
1312
c9b51268668f Updated copyright information and removed rcs id lines (problematic in branch merges)
Sam Lantinga <slouken@libsdl.org>
parents: 769
diff changeset
15 You should have received a copy of the GNU Lesser General Public
c9b51268668f Updated copyright information and removed rcs id lines (problematic in branch merges)
Sam Lantinga <slouken@libsdl.org>
parents: 769
diff changeset
16 License along with this library; if not, write to the Free Software
c9b51268668f Updated copyright information and removed rcs id lines (problematic in branch merges)
Sam Lantinga <slouken@libsdl.org>
parents: 769
diff changeset
17 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
509
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
18
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
19 Sam Lantinga
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
20 slouken@libsdl.org
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
21 */
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
22
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
23 /* An implementation of mutexes using semaphores */
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
24
1338
604d73db6802 Removed uses of stdlib.h and string.h
Sam Lantinga <slouken@libsdl.org>
parents: 1336
diff changeset
25 #include "SDL_stdlib.h"
509
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
26 #include "SDL_error.h"
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
27 #include "SDL_thread.h"
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
28 #include "SDL_systhread_c.h"
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
29
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
30 #include <arch/spinlock.h>
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
31
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
32 struct SDL_mutex {
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
33 int recursive;
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
34 Uint32 owner;
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
35 spinlock_t mutex;
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
36 };
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
37
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
38 /* Create a mutex */
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
39 SDL_mutex *SDL_CreateMutex(void)
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
40 {
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
41 SDL_mutex *mutex;
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
42
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
43 /* Allocate mutex memory */
1336
3692456e7b0f Use SDL_ prefixed versions of C library functions.
Sam Lantinga <slouken@libsdl.org>
parents: 1312
diff changeset
44 mutex = (SDL_mutex *)SDL_malloc(sizeof(*mutex));
509
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
45 if ( mutex ) {
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
46 spinlock_init(&mutex->mutex);
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
47 mutex->recursive = 0;
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
48 mutex->owner = 0;
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
49 } else {
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
50 SDL_OutOfMemory();
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
51 }
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
52 return mutex;
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
53 }
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
54
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
55 /* Free the mutex */
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
56 void SDL_DestroyMutex(SDL_mutex *mutex)
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
57 {
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
58 if ( mutex ) {
1336
3692456e7b0f Use SDL_ prefixed versions of C library functions.
Sam Lantinga <slouken@libsdl.org>
parents: 1312
diff changeset
59 SDL_free(mutex);
509
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
60 }
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
61 }
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
62
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
63 /* Lock the semaphore */
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
64 int SDL_mutexP(SDL_mutex *mutex)
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
65 {
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
66 #ifdef DISABLE_THREADS
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
67 return 0;
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
68 #else
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
69 Uint32 this_thread;
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
70
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
71 if ( mutex == NULL ) {
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
72 SDL_SetError("Passed a NULL mutex");
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
73 return -1;
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
74 }
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
75
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
76 this_thread = SDL_ThreadID();
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
77 if ( mutex->owner == this_thread ) {
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
78 ++mutex->recursive;
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
79 } else {
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
80 /* The order of operations is important.
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
81 We set the locking thread id after we obtain the lock
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
82 so unlocks from other threads will fail.
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
83 */
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
84 spinlock_lock(&mutex->mutex);
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
85 mutex->owner = this_thread;
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
86 mutex->recursive = 0;
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
87 }
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
88
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
89 return 0;
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
90 #endif /* DISABLE_THREADS */
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
91 }
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
92
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
93 /* Unlock the mutex */
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
94 int SDL_mutexV(SDL_mutex *mutex)
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
95 {
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
96 #ifdef DISABLE_THREADS
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
97 return 0;
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
98 #else
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
99 if ( mutex == NULL ) {
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
100 SDL_SetError("Passed a NULL mutex");
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
101 return -1;
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
102 }
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
103
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
104 /* If we don't own the mutex, we can't unlock it */
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
105 if ( SDL_ThreadID() != mutex->owner ) {
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
106 SDL_SetError("mutex not owned by this thread");
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
107 return -1;
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
108 }
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
109
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
110 if ( mutex->recursive ) {
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
111 --mutex->recursive;
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
112 } else {
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
113 /* The order of operations is important.
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
114 First reset the owner so another thread doesn't lock
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
115 the mutex and set the ownership before we reset it,
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
116 then release the lock semaphore.
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
117 */
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
118 mutex->owner = 0;
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
119 spinlock_unlock(&mutex->mutex);
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
120 }
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
121 return 0;
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
122 #endif /* DISABLE_THREADS */
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
123 }