| 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 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 | /* |
| 24 | SDL_syssem.cpp |
| 25 | |
| 26 | Epoc version by Markus Mertama (w@iki.fi) |
| 27 | */ |
| 28 | |
| 29 | #ifdef SAVE_RCSID |
| 30 | static char rcsid = |
| 31 | "@(#) $Id: SDL_syssem.c,v 1.1.2.4 2000/06/22 15:24:48 hercules Exp $"; |
| 32 | #endif |
| 33 | |
| 34 | /* Semaphore functions using the Win32 API */ |
| 35 | |
| 36 | //#include <stdio.h> |
| 37 | //#include <stdlib.h> |
| 38 | #include <e32std.h> |
| 39 | |
| 40 | #include "SDL_error.h" |
| 41 | #include "SDL_thread.h" |
| 42 | |
| 43 | |
| 44 | #define SDL_MUTEX_TIMEOUT -2 |
| 45 | |
| 46 | struct SDL_semaphore |
| 47 | { |
| 48 | TInt handle; |
| 49 | TInt count; |
| 50 | }; |
| 51 | |
| 52 | |
| 53 | extern TInt CreateUnique(TInt (*aFunc)(const TDesC& aName, TAny*, TAny*), TAny*, TAny*); |
| 54 | #ifndef EKA2 |
| 55 | extern TInt NewThread(const TDesC& aName, TAny* aPtr1, TAny* aPtr2); |
| 56 | #endif |
| 57 | |
| 58 | TInt NewSema(const TDesC& aName, TAny* aPtr1, TAny* aPtr2) |
| 59 | { |
| 60 | TInt value = *((TInt*) aPtr2); |
| 61 | return ((RSemaphore*)aPtr1)->CreateGlobal(aName, value); |
| 62 | } |
| 63 | |
| 64 | /* Create a semaphore */ |
| 65 | SDL_sem *SDL_CreateSemaphore(Uint32 initial_value) |
| 66 | { |
| 67 | RSemaphore s; |
| 68 | TInt status = CreateUnique(NewSema, &s, &initial_value); |
| 69 | if(status != KErrNone) |
| 70 | { |
| 71 | SDL_SetError("Couldn't create semaphore"); |
| 72 | } |
| 73 | SDL_semaphore* sem = new /*(ELeave)*/ SDL_semaphore; |
| 74 | sem->handle = s.Handle(); |
| 75 | sem->count = initial_value; |
| 76 | return(sem); |
| 77 | } |
| 78 | |
| 79 | /* Free the semaphore */ |
| 80 | void SDL_DestroySemaphore(SDL_sem *sem) |
| 81 | { |
| 82 | if ( sem ) |
| 83 | { |
| 84 | RSemaphore sema; |
| 85 | sema.SetHandle(sem->handle); |
| 86 | while(--sem->count) |
| 87 | sema.Signal(); |
| 88 | sema.Close(); |
| 89 | delete sem; |
| 90 | sem = NULL; |
| 91 | } |
| 92 | } |
| 93 | |
| 94 | #ifndef EKA2 |
| 95 | |
| 96 | struct TInfo |
| 97 | { |
| 98 | TInfo(TInt aTime, TInt aHandle) : |
| 99 | iTime(aTime), iHandle(aHandle), iVal(0) {} |
| 100 | TInt iTime; |
| 101 | TInt iHandle; |
| 102 | TInt iVal; |
| 103 | }; |
| 104 | |
| 105 | |
| 106 | |
| 107 | TBool ThreadRun(TAny* aInfo) |
| 108 | { |
| 109 | TInfo* info = STATIC_CAST(TInfo*, aInfo); |
| 110 | User::After(info->iTime); |
| 111 | RSemaphore sema; |
| 112 | sema.SetHandle(info->iHandle); |
| 113 | sema.Signal(); |
| 114 | info->iVal = SDL_MUTEX_TIMEOUT; |
| 115 | return 0; |
| 116 | } |
| 117 | |
| 118 | #endif |
| 119 | |
| 120 | |
| 121 | void _WaitAll(SDL_sem *sem) |
| 122 | { |
| 123 | //since SemTryWait may changed the counter. |
| 124 | //this may not be atomic, but hopes it works. |
| 125 | RSemaphore sema; |
| 126 | sema.SetHandle(sem->handle); |
| 127 | sema.Wait(); |
| 128 | while(sem->count < 0) |
| 129 | { |
| 130 | sema.Wait(); |
| 131 | } |
| 132 | } |
| 133 | |
| 134 | int SDL_SemWaitTimeout(SDL_sem *sem, Uint32 timeout) |
| 135 | { |
| 136 | if ( ! sem ) { |
| 137 | SDL_SetError("Passed a NULL sem"); |
| 138 | return -1; |
| 139 | } |
| 140 | |
| 141 | if ( timeout == SDL_MUTEX_MAXWAIT ) |
| 142 | { |
| 143 | _WaitAll(sem); |
| 144 | return SDL_MUTEX_MAXWAIT; |
| 145 | } |
| 146 | |
| 147 | #ifdef EKA2 |
| 148 | |
| 149 | RSemaphore sema; |
| 150 | sema.SetHandle(sem->handle); |
| 151 | if(KErrNone == sema.Wait(timeout)) |
| 152 | return 0; |
| 153 | return -1; |
| 154 | #else |
| 155 | RThread thread; |
| 156 | |
| 157 | TInfo* info = new (ELeave)TInfo(timeout, sem->handle); |
| 158 | |
| 159 | TInt status = CreateUnique(NewThread, &thread, info); |
| 160 | |
| 161 | if(status != KErrNone) |
| 162 | return status; |
| 163 | |
| 164 | thread.Resume(); |
| 165 | |
| 166 | _WaitAll(sem); |
| 167 | |
| 168 | if(thread.ExitType() == EExitPending) |
| 169 | { |
| 170 | thread.Kill(SDL_MUTEX_TIMEOUT); |
| 171 | } |
| 172 | |
| 173 | thread.Close(); |
| 174 | |
| 175 | return info->iVal; |
| 176 | #endif |
| 177 | } |
| 178 | |
| 179 | int SDL_SemTryWait(SDL_sem *sem) |
| 180 | { |
| 181 | if(sem->count > 0) |
| 182 | { |
| 183 | sem->count--; |
| 184 | } |
| 185 | return SDL_MUTEX_TIMEOUT; |
| 186 | } |
| 187 | |
| 188 | int SDL_SemWait(SDL_sem *sem) |
| 189 | { |
| 190 | return SDL_SemWaitTimeout(sem, SDL_MUTEX_MAXWAIT); |
| 191 | } |
| 192 | |
| 193 | /* Returns the current count of the semaphore */ |
| 194 | Uint32 SDL_SemValue(SDL_sem *sem) |
| 195 | { |
| 196 | if ( ! sem ) { |
| 197 | SDL_SetError("Passed a NULL sem"); |
| 198 | return 0; |
| 199 | } |
| 200 | return sem->count; |
| 201 | } |
| 202 | |
| 203 | int SDL_SemPost(SDL_sem *sem) |
| 204 | { |
| 205 | if ( ! sem ) { |
| 206 | SDL_SetError("Passed a NULL sem"); |
| 207 | return -1; |
| 208 | } |
| 209 | sem->count++; |
| 210 | RSemaphore sema; |
| 211 | sema.SetHandle(sem->handle); |
| 212 | sema.Signal(); |
| 213 | return 0; |
| 214 | } |