| 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 | } |