Mercurial > sdl-ios-xcode
annotate src/thread/generic/SDL_syssem.c @ 1554:0ca607a5d173
Fixed bug #84
Date: Sun, 23 Oct 2005 16:39:03 +0200
From: "A. Schmid" <sahib@phreaker.net>
Subject: [SDL] no software surfaces with svgalib driver?
Hi,
I noticed that the SDL (1.2.9) svgalib driver only makes use of linear
addressable (framebuffer) video modes. On older systems (like one of
mine), linear addressable modes are often not available.
Especially for cards with VESA VBE < 2.0 the svgalib vesa driver is
unusable, since VESA only supports framebuffering for VBE 2.0 and later.
The changes necessary to add support for software surfaces seem to be
relatively small. I only had to hack src/video/svga/SDL_svgavideo.c (see
attached patch). The code worked fine for me, but it is no more than a
proof of concept and should be reviewed (probably has a memory leak when
switching modes). It also uses the vgagl library (included in the
svgalib package) and needs to be linked against it.
-Alex
| author | Sam Lantinga <slouken@libsdl.org> |
|---|---|
| date | Sun, 19 Mar 2006 12:04:40 +0000 |
| parents | d910939febfa |
| children | aee7ea396f59 |
| rev | line source |
|---|---|
| 0 | 1 /* |
| 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 |
| 0 | 4 |
| 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 |
| 0 | 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. |
| 0 | 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 | |
|
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. |
| 0 | 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 |
| 0 | 18 |
| 19 Sam Lantinga | |
|
252
e8157fcb3114
Updated the source with the correct e-mail address
Sam Lantinga <slouken@libsdl.org>
parents:
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20 slouken@libsdl.org |
| 0 | 21 */ |
|
1402
d910939febfa
Use consistent identifiers for the various platforms we support.
Sam Lantinga <slouken@libsdl.org>
parents:
1361
diff
changeset
|
22 #include "SDL_config.h" |
| 0 | 23 |
| 24 /* An implementation of semaphores using mutexes and condition variables */ | |
| 25 | |
| 26 #include "SDL_timer.h" | |
| 27 #include "SDL_thread.h" | |
| 28 #include "SDL_systhread_c.h" | |
| 29 | |
| 30 | |
|
1361
19418e4422cb
New configure-based build system. Still work in progress, but much improved
Sam Lantinga <slouken@libsdl.org>
parents:
1358
diff
changeset
|
31 #if SDL_THREADS_DISABLED |
| 0 | 32 |
| 33 SDL_sem *SDL_CreateSemaphore(Uint32 initial_value) | |
| 34 { | |
| 35 SDL_SetError("SDL not configured with thread support"); | |
| 36 return (SDL_sem *)0; | |
| 37 } | |
| 38 | |
| 39 void SDL_DestroySemaphore(SDL_sem *sem) | |
| 40 { | |
| 41 return; | |
| 42 } | |
| 43 | |
| 44 int SDL_SemTryWait(SDL_sem *sem) | |
| 45 { | |
| 46 SDL_SetError("SDL not configured with thread support"); | |
| 47 return -1; | |
| 48 } | |
| 49 | |
| 50 int SDL_SemWaitTimeout(SDL_sem *sem, Uint32 timeout) | |
| 51 { | |
| 52 SDL_SetError("SDL not configured with thread support"); | |
| 53 return -1; | |
| 54 } | |
| 55 | |
| 56 int SDL_SemWait(SDL_sem *sem) | |
| 57 { | |
| 58 SDL_SetError("SDL not configured with thread support"); | |
| 59 return -1; | |
| 60 } | |
| 61 | |
| 62 Uint32 SDL_SemValue(SDL_sem *sem) | |
| 63 { | |
| 64 return 0; | |
| 65 } | |
| 66 | |
| 67 int SDL_SemPost(SDL_sem *sem) | |
| 68 { | |
| 69 SDL_SetError("SDL not configured with thread support"); | |
| 70 return -1; | |
| 71 } | |
| 72 | |
| 73 #else | |
| 74 | |
| 75 struct SDL_semaphore | |
| 76 { | |
| 77 Uint32 count; | |
| 78 Uint32 waiters_count; | |
| 79 SDL_mutex *count_lock; | |
| 80 SDL_cond *count_nonzero; | |
| 81 }; | |
| 82 | |
| 83 SDL_sem *SDL_CreateSemaphore(Uint32 initial_value) | |
| 84 { | |
| 85 SDL_sem *sem; | |
| 86 | |
|
1336
3692456e7b0f
Use SDL_ prefixed versions of C library functions.
Sam Lantinga <slouken@libsdl.org>
parents:
1330
diff
changeset
|
87 sem = (SDL_sem *)SDL_malloc(sizeof(*sem)); |
| 0 | 88 if ( ! sem ) { |
| 89 SDL_OutOfMemory(); | |
| 90 return(0); | |
| 91 } | |
| 92 sem->count = initial_value; | |
| 93 sem->waiters_count = 0; | |
| 94 | |
| 95 sem->count_lock = SDL_CreateMutex(); | |
| 96 sem->count_nonzero = SDL_CreateCond(); | |
| 97 if ( ! sem->count_lock || ! sem->count_nonzero ) { | |
| 98 SDL_DestroySemaphore(sem); | |
| 99 return(0); | |
| 100 } | |
| 101 | |
| 102 return(sem); | |
| 103 } | |
| 104 | |
| 105 /* WARNING: | |
| 106 You cannot call this function when another thread is using the semaphore. | |
| 107 */ | |
| 108 void SDL_DestroySemaphore(SDL_sem *sem) | |
| 109 { | |
| 110 if ( sem ) { | |
| 111 sem->count = 0xFFFFFFFF; | |
| 112 while ( sem->waiters_count > 0) { | |
| 113 SDL_CondSignal(sem->count_nonzero); | |
| 114 SDL_Delay(10); | |
| 115 } | |
| 116 SDL_DestroyCond(sem->count_nonzero); | |
| 117 SDL_mutexP(sem->count_lock); | |
| 118 SDL_mutexV(sem->count_lock); | |
| 119 SDL_DestroyMutex(sem->count_lock); | |
|
1336
3692456e7b0f
Use SDL_ prefixed versions of C library functions.
Sam Lantinga <slouken@libsdl.org>
parents:
1330
diff
changeset
|
120 SDL_free(sem); |
| 0 | 121 } |
| 122 } | |
| 123 | |
| 124 int SDL_SemTryWait(SDL_sem *sem) | |
| 125 { | |
| 126 int retval; | |
| 127 | |
| 128 if ( ! sem ) { | |
| 129 SDL_SetError("Passed a NULL semaphore"); | |
| 130 return -1; | |
| 131 } | |
| 132 | |
| 133 retval = SDL_MUTEX_TIMEDOUT; | |
| 134 SDL_LockMutex(sem->count_lock); | |
| 135 if ( sem->count > 0 ) { | |
| 136 --sem->count; | |
| 137 retval = 0; | |
| 138 } | |
| 139 SDL_UnlockMutex(sem->count_lock); | |
| 140 | |
| 141 return retval; | |
| 142 } | |
| 143 | |
| 144 int SDL_SemWaitTimeout(SDL_sem *sem, Uint32 timeout) | |
| 145 { | |
| 146 int retval; | |
| 147 | |
| 148 if ( ! sem ) { | |
| 149 SDL_SetError("Passed a NULL semaphore"); | |
| 150 return -1; | |
| 151 } | |
| 152 | |
| 153 /* A timeout of 0 is an easy case */ | |
| 154 if ( timeout == 0 ) { | |
| 155 return SDL_SemTryWait(sem); | |
| 156 } | |
| 157 | |
| 158 SDL_LockMutex(sem->count_lock); | |
| 159 ++sem->waiters_count; | |
| 160 retval = 0; | |
| 161 while ( (sem->count == 0) && (retval != SDL_MUTEX_TIMEDOUT) ) { | |
| 162 retval = SDL_CondWaitTimeout(sem->count_nonzero, | |
| 163 sem->count_lock, timeout); | |
| 164 } | |
| 165 --sem->waiters_count; | |
| 166 --sem->count; | |
| 167 SDL_UnlockMutex(sem->count_lock); | |
| 168 | |
| 169 return retval; | |
| 170 } | |
| 171 | |
| 172 int SDL_SemWait(SDL_sem *sem) | |
| 173 { | |
| 174 return SDL_SemWaitTimeout(sem, SDL_MUTEX_MAXWAIT); | |
| 175 } | |
| 176 | |
| 177 Uint32 SDL_SemValue(SDL_sem *sem) | |
| 178 { | |
| 179 Uint32 value; | |
| 180 | |
| 181 value = 0; | |
| 182 if ( sem ) { | |
| 183 SDL_LockMutex(sem->count_lock); | |
| 184 value = sem->count; | |
| 185 SDL_UnlockMutex(sem->count_lock); | |
| 186 } | |
| 187 return value; | |
| 188 } | |
| 189 | |
| 190 int SDL_SemPost(SDL_sem *sem) | |
| 191 { | |
| 192 if ( ! sem ) { | |
| 193 SDL_SetError("Passed a NULL semaphore"); | |
| 194 return -1; | |
| 195 } | |
| 196 | |
| 197 SDL_LockMutex(sem->count_lock); | |
| 198 if ( sem->waiters_count > 0 ) { | |
| 199 SDL_CondSignal(sem->count_nonzero); | |
| 200 } | |
| 201 ++sem->count; | |
| 202 SDL_UnlockMutex(sem->count_lock); | |
| 203 | |
| 204 return 0; | |
| 205 } | |
| 206 | |
|
1361
19418e4422cb
New configure-based build system. Still work in progress, but much improved
Sam Lantinga <slouken@libsdl.org>
parents:
1358
diff
changeset
|
207 #endif /* SDL_THREADS_DISABLED */ |