src/xbt/xbt_thread.c

   1 /* $Id$ */
   2
   3 /* xbt_thread -- portability layer over the pthread API                     */
   4
   5 /* Copyright 2006,2007 Malek Cherier, Martin Quinson
   6  * All right reserved.                                                      */
   7
   8 /* This program is free software; you can redistribute it and/or modify it
   9  * under the terms of the license (GNU LGPL) which comes with this package. */
  10
  11 #include "xbt/sysdep.h"
  12 #include "xbt/ex.h"
  13 #include "portable.h"
  14 #include "xbt/xbt_thread.h" /* This module */
  15 #include "xbt_modinter.h" /* Initialization/finalization of this module */
  16
  17
  18
  19 /* ********************************* PTHREAD IMPLEMENTATION ************************************ */
  20 #ifdef HAVE_PTHREAD_H
  21 #include <pthread.h>
  22
  23 typedef struct xbt_thread_ {
  24    pthread_t t;
  25 } s_xbt_thread_t ;
  26
  27 /* thread-specific data containing the xbt_thread_t structure */
  28 pthread_key_t xbt_self_thread_key;
  29
  30 /* frees the xbt_thread_t corresponding to the current thread */
  31 static void xbt_thread_free_thread_data(void*d){
  32    free(d);
  33 }
  34
  35 void xbt_thread_mod_init(void) {
  36    int errcode;
  37
  38    if ((errcode=pthread_key_create(&thread_data, &xbt_thread_free_thread_data)))
  39      THROW0(system_error,errcode,"pthread_key_create failed for thread_data");
  40 }
  41 void xbt_thread_mod_exit(void) {
  42    int errcode;
  43
  44    if ((errcode=pthread_key_delete(thread_data)))
  45      THROW0(system_error,errcode,"pthread_key_delete failed for thread_data");
  46 }
  47
  48
  49 xbt_thread_t xbt_thread_create(pvoid_f_pvoid_t start_routine,
  50                                void* param)  {
  51    xbt_thread_t res = xbt_new(s_xbt_thread_t,1);
  52    int errcode;
  53
  54    if ((errcode=pthread_setspecific(thread_data,res)))
  55      THROW0(system_error,errcode,"pthread_setspecific failed for thread_data");
  56
  57    if ((errcode = pthread_create(&(res->t), NULL, start_routine, param)))
  58      THROW0(system_error,errcode, "pthread_create failed");
  59
  60    return res;
  61 }
  62 void xbt_thread_exit(int *retval) {
  63    pthread_exit(retval);
  64 }
  65 xbt_thread_t xbt_thread_self(void) {
  66    return pthread_getspecific(thread_data);
  67 }
  68
  69 #include <sched.h>
  70 void xbt_thread_yield(void) {
  71    sched_yield();
  72 }
  73 /****** mutex related functions ******/
  74 typedef struct xbt_mutex_ {
  75    pthread_mutex_t m;
  76 } s_xbt_mutex_t;
  77
  78 xbt_mutex_t xbt_mutex_init(void) {
  79    xbt_mutex_t res = xbt_new(s_xbt_mutex_t,1);
  80    int errcode;
  81
  82    if ((errcode = pthread_mutex_init(&(res->m),NULL)))
  83      THROW0(system_error,errcode,"pthread_mutex_init() failed");
  84
  85    return res;
  86 }
  87
  88 void xbt_mutex_lock(xbt_mutex_t mutex) {
  89    int errcode;
  90
  91    if ((errcode=pthread_mutex_lock(&(mutex->m))))
  92      THROW1(system_error,errcode,"pthread_mutex_lock(%p) failed",mutex);
  93 }
  94
  95 void xbt_mutex_unlock(xbt_mutex_t mutex) {
  96    int errcode;
  97
  98    if ((errcode=pthread_mutex_unlock(&(mutex->m))))
  99      THROW1(system_error,errcode,"pthread_mutex_unlock(%p) failed",mutex);
 100 }
 101
 102 void xbt_mutex_destroy(xbt_mutex_t mutex) {
 103    int errcode;
 104
 105    if ((errcode=pthread_mutex_destroy(&(mutex->m))))
 106      THROW1(system_error,errcode,"pthread_mutex_destroy(%p) failed",mutex);
 107    free(mutex);
 108 }
 109
 110 /***** condition related functions *****/
 111 typedef struct xbt_thcond_ {
 112    pthread_cond_t c;
 113 } s_xbt_thcond_t;
 114
 115 xbt_thcond_t xbt_thcond_init(void) {
 116    xbt_thcond_t res = xbt_new(s_xbt_thcond_t,1);
 117    int errcode;
 118    if ((errcode=pthread_cond_init(&(res->c),NULL)))
 119      THROW0(system_error,errcode,"pthread_cond_init() failed");
 120
 121    return res;
 122 }
 123
 124 void xbt_thcond_wait(xbt_thcond_t cond, xbt_mutex_t mutex) {
 125    int errcode;
 126    if ((errcode=pthread_cond_wait(&(cond->c),&(mutex->m))))
 127      THROW2(system_error,errcode,"pthread_cond_wait(%p,%p) failed",cond,mutex);
 128 }
 129
 130 void xbt_thcond_signal(xbt_thcond_t cond) {
 131    int errcode;
 132    if ((errcode=pthread_cond_signal(&(cond->c))))
 133      THROW1(system_error,errcode,"pthread_cond_signal(%p) failed",cond);
 134 }
 135
 136 void xbt_thcond_broadcast(xbt_thcond_t cond){
 137    int errcode;
 138    if ((errcode=pthread_cond_broadcast(&(cond->c))))
 139      THROW1(system_error,errcode,"pthread_cond_broadcast(%p) failed",cond);
 140 }
 141 void xbt_thcond_destroy(xbt_thcond_t cond){
 142    int errcode;
 143    if ((errcode=pthread_cond_destroy(&(cond->c))))
 144      THROW1(system_error,errcode,"pthread_cond_destroy(%p) failed",cond);
 145    free(cond);
 146 }
 147
 148 /* ********************************* WINDOWS IMPLEMENTATION ************************************ */
 149
 150 #elif defined(WIN32)
 151
 152 typedef struct xbt_thread_ {
 153    HANDLE handle;                  /* the win thread handle        */
 154    unsigned long id;               /* the win thread id            */
 155 } s_xbt_thread_t ;
 156
 157 /* key to the TLS containing the xbt_thread_t structure */
 158 unsigned long xbt_self_thread_key;
 159
 160 void xbt_thread_mod_init(void) {
 161    xbt_self_thread_key = TlsAlloc();
 162 }
 163 void xbt_thread_mod_exit(void) {
 164    int errcode;
 165    if (!(errcode = TlsFree(xbt_self_thread_key)))
 166      THROW0(system_error,errcode,"TlsFree() failed to cleanup the thread submodule");
 167 }
 168
 169 xbt_thread_t xbt_thread_create(pvoid_f_pvoid_t start_routine,
 170                                void* param)  {
 171
 172    xbt_thread_t res = xbt_new(s_xbt_thread_t,1);
 173
 174    res->handle = CreateThread(NULL,0,
 175                               (LPTHREAD_START_ROUTINE)start_routine,
 176                               param,0,& res->id);
 177
 178    if(!res->handle) {
 179      xbt_free(res);
 180      THROW0(system_error,0,"CreateThread failed");
 181    }
 182
 183    if(!TlsSetValue(xbt_self_thread_key,res))
 184      THROW0(system_error,0,"TlsSetValue of data describing the created thread failed");
 185
 186    return res;
 187 }
 188
 189 void xbt_thread_exit(int *retval) {
 190    xbt_thread_t self = xbt_thread_self();
 191
 192    CloseHandle(self->handle);
 193    free(self);
 194
 195    ExitThread(*retval);
 196 }
 197
 198 xbt_thread_t xbt_thread_self(void) {
 199    return TlsGetValue(xbt_self_thread_key);
 200 }
 201
 202 void xbt_thread_yield(void) {
 203     Sleep(0);
 204 }
 205
 206 /****** mutex related functions ******/
 207 typedef struct xbt_mutex_ {
 208    CRITICAL_SECTION lock;
 209 } s_xbt_mutex_t;
 210
 211 xbt_mutex_t xbt_mutex_init(void) {
 212    xbt_mutex_t res = xbt_new(s_xbt_mutex_t,1);
 213
 214    /* initialize the critical section object */
 215    InitializeCriticalSection(&(res->lock));
 216
 217    return res;
 218 }
 219
 220 void xbt_mutex_lock(xbt_mutex_t mutex) {
 221
 222    EnterCriticalSection(& mutex->lock);
 223 }
 224
 225 void xbt_mutex_unlock(xbt_mutex_t mutex) {
 226
 227    LeaveCriticalSection (& mutex->lock);
 228
 229 }
 230
 231 void xbt_mutex_destroy(xbt_mutex_t mutex) {
 232
 233    DeleteCriticalSection(& mutex->lock);
 234
 235    free(mutex);
 236 }
 237
 238 /***** condition related functions *****/
 239  enum {
 240     SIGNAL = 0,
 241     BROADCAST = 1,
 242     MAX_EVENTS = 2
 243  };
 244
 245 typedef struct xbt_thcond_ {
 246    HANDLE events[MAX_EVENTS];
 247
 248    unsigned int waiters_count;           /* the number of waiters                        */
 249    CRITICAL_SECTION waiters_count_lock;  /* protect access to waiters_count  */
 250 } s_xbt_thcond_t;
 251
 252 xbt_thcond_t xbt_thcond_init(void) {
 253
 254    xbt_thcond_t res = xbt_new0(s_xbt_thcond_t,1);
 255
 256    memset(& res->waiters_count_lock,0,sizeof(CRITICAL_SECTION));
 257
 258    /* initialize the critical section object */
 259    InitializeCriticalSection(& res->waiters_count_lock);
 260
 261    res->waiters_count = 0;
 262
 263    /* Create an auto-reset event */
 264    res->events[SIGNAL] = CreateEvent (NULL, FALSE, FALSE, NULL);
 265
 266    if(!res->events[SIGNAL]){
 267       DeleteCriticalSection(& res->waiters_count_lock);
 268       free(res);
 269       THROW0(system_error,0,"CreateEvent failed for the signals");
 270    }
 271
 272    /* Create a manual-reset event. */
 273    res->events[BROADCAST] = CreateEvent (NULL, TRUE, FALSE,NULL);
 274
 275    if(!res->events[BROADCAST]){
 276
 277       DeleteCriticalSection(& res->waiters_count_lock);
 278       CloseHandle(res->events[SIGNAL]);
 279       free(res);
 280       THROW0(system_error,0,"CreateEvent failed for the broadcasts");
 281    }
 282
 283    return res;
 284 }
 285
 286 void xbt_thcond_wait(xbt_thcond_t cond, xbt_mutex_t mutex) {
 287
 288    unsigned long wait_result;
 289    int is_last_waiter;
 290
 291    /* lock the threads counter and increment it */
 292    EnterCriticalSection (& cond->waiters_count_lock);
 293    cond->waiters_count++;
 294    LeaveCriticalSection (& cond->waiters_count_lock);
 295
 296    /* unlock the mutex associate with the condition */
 297    LeaveCriticalSection (& mutex->lock);
 298
 299    /* wait for a signal (broadcast or no) */
 300    wait_result = WaitForMultipleObjects (2, cond->events, FALSE, INFINITE);
 301
 302    if(wait_result == WAIT_FAILED)
 303      THROW0(system_error,0,"WaitForMultipleObjects failed, so we cannot wait on the condition");
 304
 305    /* we have a signal lock the condition */
 306    EnterCriticalSection (& cond->waiters_count_lock);
 307    cond->waiters_count--;
 308
 309    /* it's the last waiter or it's a broadcast ? */
 310    is_last_waiter = ((wait_result == WAIT_OBJECT_0 + BROADCAST - 1) && (cond->waiters_count == 0));
 311
 312    LeaveCriticalSection (& cond->waiters_count_lock);
 313
 314    /* yes it's the last waiter or it's a broadcast
 315     * only reset the manual event (the automatic event is reset in the WaitForMultipleObjects() function
 316     * by the system.
 317     */
 318    if (is_last_waiter)
 319       if(!ResetEvent (cond->events[BROADCAST]))
 320         THROW0(system_error,0,"ResetEvent failed");
 321
 322    /* relock the mutex associated with the condition in accordance with the posix thread specification */
 323    EnterCriticalSection (& mutex->lock);
 324 }
 325
 326 void xbt_thcond_signal(xbt_thcond_t cond) {
 327    int have_waiters;
 328
 329    EnterCriticalSection (& cond->waiters_count_lock);
 330    have_waiters = cond->waiters_count > 0;
 331    LeaveCriticalSection (& cond->waiters_count_lock);
 332
 333    if (have_waiters)
 334      if(!SetEvent(cond->events[SIGNAL]))
 335        THROW0(system_error,0,"SetEvent failed");
 336 }
 337
 338 void xbt_thcond_broadcast(xbt_thcond_t cond){
 339    int have_waiters;
 340
 341    EnterCriticalSection (& cond->waiters_count_lock);
 342    have_waiters = cond->waiters_count > 0;
 343    LeaveCriticalSection (& cond->waiters_count_lock);
 344
 345    if (have_waiters)
 346      SetEvent(cond->events[BROADCAST]);
 347 }
 348
 349 void xbt_thcond_destroy(xbt_thcond_t cond){
 350    int error = 0;
 351
 352    if(!CloseHandle(cond->events[SIGNAL]))
 353      error = 1;
 354
 355    if(!CloseHandle(cond->events[BROADCAST]))
 356      error = 1;
 357
 358    DeleteCriticalSection(& cond->waiters_count_lock);
 359
 360    xbt_free(cond);
 361
 362    if (error)
 363      THROW0(system_error,0,"Error while destroying the condition");
 364 }
 365
 366 #endif