cinelerra-5.0/guicast/condition.C

   1
   2 /*
   3  * CINELERRA
   4  * Copyright (C) 2008 Adam Williams <broadcast at earthling dot net>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  *
  20  */
  21
  22 #ifndef NO_GUICAST
  23 #include "bcsignals.h"
  24 #endif
  25 #include "condition.h"
  26
  27 #include <errno.h>
  28 #include <stdio.h>
  29 #include <stdint.h>
  30 #include <sys/time.h>
  31 #include <unistd.h>
  32
  33 Condition::Condition(int init_value, const char *title, int is_binary)
  34 {
  35         this->is_binary = is_binary;
  36         this->title = title;
  37         pthread_mutex_init(&mutex, 0);
  38         pthread_cond_init(&cond, NULL);
  39         this->value = this->init_value = init_value;
  40 }
  41
  42 Condition:: ~Condition()
  43 {
  44         pthread_cond_destroy(&cond);
  45         pthread_mutex_destroy(&mutex);
  46 #ifndef NO_GUICAST
  47         UNSET_ALL_LOCKS(this);
  48 #endif
  49 }
  50
  51 void Condition::reset()
  52 {
  53         pthread_cond_destroy(&cond);
  54         pthread_mutex_destroy(&mutex);
  55         pthread_mutex_init(&mutex, 0);
  56         pthread_cond_init(&cond, NULL);
  57         value = init_value;
  58 }
  59
  60 void Condition::lock(const char *location)
  61 {
  62 #ifndef NO_GUICAST
  63         SET_LOCK(this, title, location);
  64 #endif
  65         pthread_mutex_lock(&mutex);
  66         while(value <= 0) pthread_cond_wait(&cond, &mutex);
  67 #ifndef NO_GUICAST
  68         UNSET_LOCK2
  69 #endif
  70         if(is_binary)
  71                 value = 0;
  72         else
  73                 value--;
  74         pthread_mutex_unlock(&mutex);
  75 }
  76
  77 void Condition::unlock()
  78 {
  79 // The lock trace is created and removed by the acquirer
  80 //#ifndef NO_GUICAST
  81 //      UNSET_LOCK(this);
  82 //#endif
  83         pthread_mutex_lock(&mutex);
  84         if(is_binary)
  85                 value = 1;
  86         else
  87                 value++;
  88         pthread_cond_signal(&cond);
  89         pthread_mutex_unlock(&mutex);
  90 }
  91
  92 int Condition::timed_lock(int microseconds, const char *location)
  93 {
  94         int result = 0;
  95
  96 #ifndef NO_GUICAST
  97         SET_LOCK(this, title, location);
  98 #endif
  99         pthread_mutex_lock(&mutex);
 100
 101         struct timeval now;
 102         gettimeofday(&now, 0);
 103 #if 1
 104         struct timespec timeout;
 105         timeout.tv_sec = now.tv_sec + microseconds / 1000000;
 106         timeout.tv_nsec = now.tv_usec * 1000 + (microseconds % 1000000) * 1000;
 107         while(value <= 0 && result != ETIMEDOUT)
 108         {
 109                 result = pthread_cond_timedwait(&cond, &mutex, &timeout);
 110         }
 111
 112         if( result )
 113                 result = result == ETIMEDOUT ? 1 : -1;
 114
 115 #else
 116         struct timeval timeout;
 117         int64_t timeout_msec = ((int64_t)microseconds / 1000);
 118 // This is based on the most common frame rate since it's mainly used in
 119 // recording.
 120         while( value <= 0 && !result ) {
 121                 pthread_mutex_unlock(&mutex);
 122                 usleep(20000);
 123                 gettimeofday(&timeout, 0);
 124                 timeout.tv_usec -= now.tv_usec;
 125                 timeout.tv_sec -= now.tv_sec;
 126                 pthread_mutex_lock(&mutex);
 127                 if( value > 0 ) break;
 128                 if( (int64_t)timeout.tv_sec * 1000 +
 129                     (int64_t)timeout.tv_usec / 1000 > timeout_msec )
 130                         result = 1;
 131         }
 132 #endif
 133
 134 #ifndef NO_GUICAST
 135         UNSET_LOCK2
 136 #endif
 137 //printf("Condition::timed_lock 2 %d %s %s\n", result, title, location);
 138         if( !result ) {
 139                 if(is_binary)
 140                         value = 0;
 141                 else
 142                         --value;
 143         }
 144         pthread_mutex_unlock(&mutex);
 145         return result;
 146 }
 147
 148
 149 int Condition::get_value()
 150 {
 151         return value;
 152 }