e14743d1 |
1 | /* |
2 | SDL - Simple DirectMedia Layer |
3 | Copyright (C) 1997-2009 Sam Lantinga |
4 | |
5 | This library is free software; you can redistribute it and/or |
6 | modify it under the terms of the GNU Lesser General Public |
7 | License as published by the Free Software Foundation; either |
8 | version 2.1 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 | Lesser General Public License for more details. |
14 | |
15 | You should have received a copy of the GNU Lesser General Public |
16 | License along with this library; if not, write to the Free Software |
17 | Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA |
18 | |
19 | Sam Lantinga |
20 | slouken@libsdl.org |
21 | */ |
22 | #include "SDL_config.h" |
23 | |
24 | /* Mutex functions using the OS/2 API */ |
25 | |
26 | #define INCL_DOSERRORS |
27 | #define INCL_DOSSEMAPHORES |
28 | #include <os2.h> |
29 | |
30 | #include "SDL_mutex.h" |
31 | |
32 | |
33 | struct SDL_mutex { |
34 | HMTX hmtxID; |
35 | }; |
36 | |
37 | /* Create a mutex */ |
38 | DECLSPEC SDL_mutex * SDLCALL SDL_CreateMutex(void) |
39 | { |
40 | SDL_mutex *mutex; |
41 | APIRET ulrc; |
42 | |
43 | /* Allocate mutex memory */ |
44 | mutex = (SDL_mutex *)SDL_malloc(sizeof(*mutex)); |
45 | if (mutex) |
46 | { |
47 | /* Create the mutex, with initial value signaled */ |
48 | ulrc = DosCreateMutexSem(NULL, // Create unnamed semaphore |
49 | &(mutex->hmtxID), // Pointer to handle |
50 | 0L, // Flags: create it private (not shared) |
51 | FALSE); // Initial value: unowned |
52 | if (ulrc!=NO_ERROR) |
53 | { |
54 | SDL_SetError("Couldn't create mutex"); |
55 | SDL_free(mutex); |
56 | mutex = NULL; |
57 | } |
58 | } else { |
59 | SDL_OutOfMemory(); |
60 | } |
61 | return(mutex); |
62 | } |
63 | |
64 | /* Free the mutex */ |
65 | DECLSPEC void SDLCALL SDL_DestroyMutex(SDL_mutex *mutex) |
66 | { |
67 | if ( mutex ) |
68 | { |
69 | if ( mutex->hmtxID ) |
70 | { |
71 | DosCloseMutexSem(mutex->hmtxID); |
72 | mutex->hmtxID = 0; |
73 | } |
74 | SDL_free(mutex); |
75 | } |
76 | } |
77 | |
78 | /* Lock the mutex */ |
79 | DECLSPEC int SDLCALL SDL_mutexP(SDL_mutex *mutex) |
80 | { |
81 | if ( mutex == NULL ) |
82 | { |
83 | SDL_SetError("Passed a NULL mutex"); |
84 | return -1; |
85 | } |
86 | if ( DosRequestMutexSem(mutex->hmtxID, SEM_INDEFINITE_WAIT) != NO_ERROR ) |
87 | { |
88 | SDL_SetError("Couldn't wait on mutex"); |
89 | return -1; |
90 | } |
91 | return(0); |
92 | } |
93 | |
94 | /* Unlock the mutex */ |
95 | DECLSPEC int SDLCALL SDL_mutexV(SDL_mutex *mutex) |
96 | { |
97 | if ( mutex == NULL ) |
98 | { |
99 | SDL_SetError("Passed a NULL mutex"); |
100 | return -1; |
101 | } |
102 | if ( DosReleaseMutexSem(mutex->hmtxID) != NO_ERROR ) |
103 | { |
104 | SDL_SetError("Couldn't release mutex"); |
105 | return -1; |
106 | } |
107 | return(0); |
108 | } |