Mercurial > sdl-ios-xcode

annotate src/thread/dc/SDL_syscond.c @ 3080:4094b4f1c3a1

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
More verbosity and error checking.
author Edgar Simo <bobbens@gmail.com>
date Sat, 21 Feb 2009 18:03:22 +0000
parents 99210400e8b9
children
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
2859
99210400e8b9 Updated copyright date
Sam Lantinga <slouken@libsdl.org>
parents: 1895
diff changeset
3 Copyright (C) 1997-2009 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 */
1402
d910939febfa Use consistent identifiers for the various platforms we support.
Sam Lantinga <slouken@libsdl.org>
parents: 1358
diff changeset
22 #include "SDL_config.h"
509
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
23
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
24 /* An implementation of condition variables using semaphores and mutexes */
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
25 /*
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
26 This implementation borrows heavily from the BeOS condition variable
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
27 implementation, written by Christopher Tate and Owen Smith. Thanks!
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
28 */
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 "SDL_thread.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_cond
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
33 {
1895
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
34 SDL_mutex *lock;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
35 int waiting;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
36 int signals;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
37 SDL_sem *wait_sem;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
38 SDL_sem *wait_done;
509
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
39 };
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 /* Create a condition variable */
1895
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
42 SDL_cond *
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
43 SDL_CreateCond(void)
509
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
44 {
1895
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
45 SDL_cond *cond;
509
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
46
1895
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
47 cond = (SDL_cond *) SDL_malloc(sizeof(SDL_cond));
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
48 if (cond) {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
49 cond->lock = SDL_CreateMutex();
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
50 cond->wait_sem = SDL_CreateSemaphore(0);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
51 cond->wait_done = SDL_CreateSemaphore(0);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
52 cond->waiting = cond->signals = 0;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
53 if (!cond->lock || !cond->wait_sem || !cond->wait_done) {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
54 SDL_DestroyCond(cond);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
55 cond = NULL;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
56 }
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
57 } else {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
58 SDL_OutOfMemory();
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
59 }
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
60 return (cond);
509
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 /* Destroy a condition variable */
1895
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
64 void
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
65 SDL_DestroyCond(SDL_cond * cond)
509
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
66 {
1895
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
67 if (cond) {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
68 if (cond->wait_sem) {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
69 SDL_DestroySemaphore(cond->wait_sem);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
70 }
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
71 if (cond->wait_done) {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
72 SDL_DestroySemaphore(cond->wait_done);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
73 }
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
74 if (cond->lock) {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
75 SDL_DestroyMutex(cond->lock);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
76 }
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
77 SDL_free(cond);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
78 }
509
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
79 }
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
80
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
81 /* Restart one of the threads that are waiting on the condition variable */
1895
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
82 int
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
83 SDL_CondSignal(SDL_cond * cond)
509
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
84 {
1895
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
85 if (!cond) {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
86 SDL_SetError("Passed a NULL condition variable");
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
87 return -1;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
88 }
509
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
89
1895
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
90 /* If there are waiting threads not already signalled, then
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
91 signal the condition and wait for the thread to respond.
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
92 */
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
93 SDL_LockMutex(cond->lock);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
94 if (cond->waiting > cond->signals) {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
95 ++cond->signals;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
96 SDL_SemPost(cond->wait_sem);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
97 SDL_UnlockMutex(cond->lock);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
98 SDL_SemWait(cond->wait_done);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
99 } else {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
100 SDL_UnlockMutex(cond->lock);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
101 }
509
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
102
1895
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
103 return 0;
509
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
104 }
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
105
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
106 /* Restart all threads that are waiting on the condition variable */
1895
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
107 int
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
108 SDL_CondBroadcast(SDL_cond * cond)
509
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
109 {
1895
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
110 if (!cond) {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
111 SDL_SetError("Passed a NULL condition variable");
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
112 return -1;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
113 }
509
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
114
1895
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
115 /* If there are waiting threads not already signalled, then
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
116 signal the condition and wait for the thread to respond.
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
117 */
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
118 SDL_LockMutex(cond->lock);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
119 if (cond->waiting > cond->signals) {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
120 int i, num_waiting;
509
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
121
1895
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
122 num_waiting = (cond->waiting - cond->signals);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
123 cond->signals = cond->waiting;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
124 for (i = 0; i < num_waiting; ++i) {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
125 SDL_SemPost(cond->wait_sem);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
126 }
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
127 /* Now all released threads are blocked here, waiting for us.
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
128 Collect them all (and win fabulous prizes!) :-)
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
129 */
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
130 SDL_UnlockMutex(cond->lock);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
131 for (i = 0; i < num_waiting; ++i) {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
132 SDL_SemWait(cond->wait_done);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
133 }
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
134 } else {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
135 SDL_UnlockMutex(cond->lock);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
136 }
509
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
137
1895
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
138 return 0;
509
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
139 }
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
140
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
141 /* Wait on the condition variable for at most 'ms' milliseconds.
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
142 The mutex must be locked before entering this function!
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
143 The mutex is unlocked during the wait, and locked again after the wait.
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
144
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
145 Typical use:
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
146
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
147 Thread A:
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
148 SDL_LockMutex(lock);
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
149 while ( ! condition ) {
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
150 SDL_CondWait(cond);
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
151 }
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
152 SDL_UnlockMutex(lock);
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
153
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
154 Thread B:
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
155 SDL_LockMutex(lock);
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
156 ...
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
157 condition = true;
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
158 ...
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
159 SDL_UnlockMutex(lock);
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
160 */
1895
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
161 int
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
162 SDL_CondWaitTimeout(SDL_cond * cond, SDL_mutex * mutex, Uint32 ms)
509
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
163 {
1895
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
164 int retval;
509
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
165
1895
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
166 if (!cond) {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
167 SDL_SetError("Passed a NULL condition variable");
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
168 return -1;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
169 }
509
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
170
1895
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
171 /* Obtain the protection mutex, and increment the number of waiters.
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
172 This allows the signal mechanism to only perform a signal if there
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
173 are waiting threads.
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
174 */
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
175 SDL_LockMutex(cond->lock);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
176 ++cond->waiting;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
177 SDL_UnlockMutex(cond->lock);
509
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
178
1895
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
179 /* Unlock the mutex, as is required by condition variable semantics */
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
180 SDL_UnlockMutex(mutex);
509
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
181
1895
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
182 /* Wait for a signal */
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
183 if (ms == SDL_MUTEX_MAXWAIT) {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
184 retval = SDL_SemWait(cond->wait_sem);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
185 } else {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
186 retval = SDL_SemWaitTimeout(cond->wait_sem, ms);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
187 }
509
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
188
1895
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
189 /* Let the signaler know we have completed the wait, otherwise
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
190 the signaler can race ahead and get the condition semaphore
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
191 if we are stopped between the mutex unlock and semaphore wait,
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
192 giving a deadlock. See the following URL for details:
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
193 http://www-classic.be.com/aboutbe/benewsletter/volume_III/Issue40.html
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
194 */
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
195 SDL_LockMutex(cond->lock);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
196 if (cond->signals > 0) {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
197 /* If we timed out, we need to eat a condition signal */
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
198 if (retval > 0) {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
199 SDL_SemWait(cond->wait_sem);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
200 }
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
201 /* We always notify the signal thread that we are done */
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
202 SDL_SemPost(cond->wait_done);
509
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
203
1895
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
204 /* Signal handshake complete */
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
205 --cond->signals;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
206 }
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
207 --cond->waiting;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
208 SDL_UnlockMutex(cond->lock);
509
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
209
1895
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
210 /* Lock the mutex, as is required by condition variable semantics */
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
211 SDL_LockMutex(mutex);
509
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
212
1895
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
213 return retval;
509
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
214 }
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
215
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
216 /* Wait on the condition variable forever */
1895
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
217 int
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
218 SDL_CondWait(SDL_cond * cond, SDL_mutex * mutex)
509
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
219 {
1895
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
220 return SDL_CondWaitTimeout(cond, mutex, SDL_MUTEX_MAXWAIT);
509
dad72daf44b3 Added initial support for Dreamcast (thanks HERO!)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
221 }
1895
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
222
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents: 1402
diff changeset
223 /* vi: set ts=4 sw=4 expandtab: */