cinelerra-5.1/guicast/thread.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 #include "bcsignals.h"
  23 #include <sys/wait.h>
  24 #include <sched.h>
  25 #include <signal.h>
  26 #include <stdio.h>
  27 #include <unistd.h>
  28 #include <string.h>
  29 #include <typeinfo>
  30 #include "thread.h"
  31
  32
  33 Thread::Thread(int synchronous, int realtime, int autodelete)
  34 {
  35         this->synchronous = synchronous != 0;
  36         this->realtime = realtime != 0;
  37         this->autodelete = autodelete != 0;
  38         tid = (pthread_t)-1;
  39         finished = false;
  40         cancelled = false;
  41         cancel_enabled = false;
  42 }
  43
  44 Thread::~Thread()
  45 {
  46 }
  47
  48 void* Thread::entrypoint(void *parameters)
  49 {
  50         Thread *thread = (Thread*)parameters;
  51
  52 // allow thread to be cancelled at any point during a region where it is enabled.
  53         pthread_setcanceltype(PTHREAD_CANCEL_ASYNCHRONOUS, 0);
  54 // Disable cancellation by default.
  55         pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, NULL);
  56         thread->cancel_enabled = false;
  57
  58 // Set realtime here seince it doesn't work in start
  59         if( thread->realtime && getuid() == 0 ) {
  60                 struct sched_param param = { sched_priority : 1 };
  61                 if(pthread_setschedparam(thread->tid, SCHED_RR, &param) < 0)
  62                         perror("Thread::entrypoint pthread_attr_setschedpolicy");
  63         }
  64
  65         thread->run();
  66         thread->finished = true;
  67         if( !thread->synchronous ) {
  68                 if( !thread->cancelled ) TheList::dbg_del(thread->tid);
  69                 if( thread->autodelete ) delete thread;
  70                 else thread->tid = ((pthread_t)-1);
  71         }
  72         return NULL;
  73 }
  74
  75 void Thread::start()
  76 {
  77         pthread_attr_t  attr;
  78         struct sched_param param;
  79
  80         pthread_attr_init(&attr);
  81
  82 // previously run, and did not join, join to clean up zombie
  83         if( synchronous && exists() )
  84                 join();
  85
  86         finished = false;
  87         cancelled = false;
  88         owner = get_self();
  89
  90 // Inherit realtime from current thread the easy way.
  91         if( !realtime )
  92                 realtime = calculate_realtime();
  93
  94         if( !synchronous )
  95                 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
  96
  97         if( realtime && getuid() == 0 ) {
  98                 if(pthread_attr_setschedpolicy(&attr, SCHED_RR) < 0)
  99                         perror("Thread::start pthread_attr_setschedpolicy");
 100                 param.sched_priority = 50;
 101                 if(pthread_attr_setschedparam(&attr, &param) < 0)
 102                         perror("Thread::start pthread_attr_setschedparam");
 103         }
 104         else {
 105                 if(pthread_attr_setinheritsched(&attr, PTHREAD_INHERIT_SCHED) < 0)
 106                         perror("Thread::start pthread_attr_setinheritsched");
 107         }
 108
 109         pthread_create(&tid, &attr, Thread::entrypoint, this);
 110
 111         TheList::dbg_add(tid, owner, typeid(*this).name());
 112 }
 113
 114 int Thread::cancel()
 115 {
 116         if( exists() && !cancelled ) {
 117                 LOCK_LOCKS("Thread::cancel");
 118                 pthread_cancel(tid);
 119                 cancelled = true;
 120                 if( !synchronous ) TheList::dbg_del(tid);
 121                 UNLOCK_LOCKS;
 122         }
 123         return 0;
 124 }
 125
 126 int Thread::join()   // join this thread
 127 {
 128         if( !exists() ) return 0;
 129         if( synchronous ) {
 130 // NOTE: this does not do anything if the thread is not synchronous
 131                 int ret = pthread_join(tid, 0);
 132                 if( ret ) strerror(ret);
 133                 CLEAR_LOCKS_TID(tid);
 134                 TheList::dbg_del(tid);
 135                 tid = ((pthread_t)-1);
 136 // Don't execute anything after this.
 137                 if( autodelete ) delete this;
 138         }
 139         else {
 140 // kludge
 141                 while( running() && !cancelled ) {
 142                         int ret = pthread_kill(tid, 0);
 143                         if( ret ) break;
 144                         usleep(200000);
 145                 }
 146                 tid = ((pthread_t)-1);
 147         }
 148         return 0;
 149 }
 150
 151 int Thread::enable_cancel()
 152 {
 153         if( !cancel_enabled ) {
 154                 cancel_enabled = true;
 155                 pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, NULL);
 156         }
 157         return 0;
 158 }
 159
 160 int Thread::disable_cancel()
 161 {
 162         if( cancel_enabled ) {
 163                 pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, NULL);
 164                 cancel_enabled = false;
 165         }
 166         return 0;
 167 }
 168
 169 int Thread::get_cancel_enabled()
 170 {
 171         return cancel_enabled;
 172 }
 173
 174 void Thread::exit_thread()
 175 {
 176         finished = true;
 177         pthread_exit(0);
 178 }
 179
 180
 181 int Thread::suspend_thread()
 182 {
 183         if( exists() )
 184                 pthread_kill(tid, SIGSTOP);
 185         return 0;
 186 }
 187
 188 int Thread::continue_thread()
 189 {
 190         if( exists() )
 191                 pthread_kill(tid, SIGCONT);
 192         return 0;
 193 }
 194
 195 int Thread::set_synchronous(int value)
 196 {
 197         this->synchronous = value != 0;
 198         return 0;
 199 }
 200
 201 int Thread::set_realtime(int value)
 202 {
 203         this->realtime = value != 0;
 204         return 0;
 205 }
 206
 207 int Thread::set_autodelete(int value)
 208 {
 209         this->autodelete = value != 0;
 210         return 0;
 211 }
 212
 213 int Thread::get_autodelete()
 214 {
 215         return autodelete ? 1 : 0;
 216 }
 217
 218 int Thread::get_synchronous()
 219 {
 220         return synchronous ? 1 : 0;
 221 }
 222
 223 bool Thread::calculate_realtime()
 224 {
 225 //printf("Thread::calculate_realtime %d %d\n", getpid(), sched_getscheduler(0));
 226         return (sched_getscheduler(0) == SCHED_RR ||
 227                 sched_getscheduler(0) == SCHED_FIFO);
 228 }
 229
 230 int Thread::get_realtime()
 231 {
 232         return realtime ? 1 : 0;
 233 }
 234
 235 unsigned long Thread::get_tid()
 236 {
 237         return tid;
 238 }
 239