Mercurial > sdl-ios-xcode
annotate src/audio/SDL_audiomem.c @ 44:25091c75acc4
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author | Sam Lantinga <slouken@lokigames.com> |
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date | Sun, 27 May 2001 01:04:01 +0000 |
parents | cf2af46e9e2a |
children | e8157fcb3114 |
rev | line source |
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0 | 1 /* |
2 SDL - Simple DirectMedia Layer | |
3 Copyright (C) 1997, 1998, 1999, 2000, 2001 Sam Lantinga | |
4 | |
5 This library is free software; you can redistribute it and/or | |
6 modify it under the terms of the GNU Library General Public | |
7 License as published by the Free Software Foundation; either | |
8 version 2 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 Library General Public License for more details. | |
14 | |
15 You should have received a copy of the GNU Library General Public | |
16 License along with this library; if not, write to the Free | |
17 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
18 | |
19 Sam Lantinga | |
20 slouken@devolution.com | |
21 */ | |
22 | |
23 #ifdef SAVE_RCSID | |
24 static char rcsid = | |
25 "@(#) $Id$"; | |
26 #endif | |
27 | |
28 /* Functions to allocate audio buffer memory, shareable across threads | |
29 (necessary because SDL audio emulates threads with fork() | |
30 */ | |
31 | |
1
cf2af46e9e2a
Changes since SDL 1.2.0 release
Sam Lantinga <slouken@lokigames.com>
parents:
0
diff
changeset
|
32 #include <stdlib.h> |
0 | 33 #ifdef FORK_HACK |
34 #include <sys/types.h> | |
35 #include <sys/ipc.h> | |
36 #include <sys/shm.h> | |
37 #include <stddef.h> | |
38 #endif | |
39 | |
40 #include "SDL_audiomem.h" | |
41 | |
42 /* Allocate memory that will be shared between threads (freed on exit) */ | |
43 void *SDL_AllocAudioMem(int size) | |
44 { | |
45 void *chunk; | |
46 | |
47 #ifdef FORK_HACK | |
48 int semid; | |
49 | |
50 /* Create and get the address of a shared memory segment */ | |
51 semid = shmget(IPC_PRIVATE, size, (IPC_CREAT|0600)); | |
52 if ( semid < 0 ) { | |
53 return(NULL); | |
54 } | |
55 chunk = shmat(semid, NULL, 0); | |
56 | |
57 /* Set the segment for deletion when it is detatched */ | |
58 shmctl(semid, IPC_RMID, NULL); /* Delets semid if shmat() fails */ | |
59 #else | |
60 chunk = malloc(size); | |
61 #endif | |
62 return((void *)chunk); | |
63 } | |
64 | |
65 void SDL_FreeAudioMem(void *chunk) | |
66 { | |
67 #ifdef FORK_HACK | |
68 shmdt(chunk); | |
69 #else | |
70 free(chunk); | |
71 #endif | |
72 } |