servicemp3.cpp: more simple/flexible streaming detection
[enigma2.git] / lib / base / thread.cpp
index b75378b88ba83028a35a47e265d1c87ea3e34300..1fda6a47a944efb23dd7e76a72cd7ba444991c0c 100644 (file)
 #include <lib/base/thread.h>
+
 #include <stdio.h>
+#include <unistd.h>
 #include <lib/base/eerror.h>
 
+void eThread::thread_completed(void *ptr)
+{
+       eThread *p = (eThread*) ptr;
+       p->m_alive = 0;
+
+               /* recover state in case thread was cancelled before calling hasStarted */
+       if (!p->m_started)
+               p->hasStarted();
+
+       p->thread_finished();
+}
+
 void *eThread::wrapper(void *ptr)
 {
-       ((eThread*)ptr)->thread();
+       eThread *p = (eThread*)ptr;
+       pthread_cleanup_push(thread_completed, (void*)p);
+       p->thread();
        pthread_exit(0);
+       pthread_cleanup_pop(1);
+       return 0;
 }
 
 eThread::eThread()
+       : the_thread(0), m_alive(0)
 {
-       alive=0;
 }
 
-void eThread::run()
+int eThread::runAsync(int prio, int policy)
 {
-       alive=1;
-       pthread_create(&the_thread, 0, wrapper, this);
+       eDebug("before: %d", m_state.value());
+               /* the thread might already run. */
+       if (sync())
+               return -1;
+       
+       eDebug("after: %d", m_state.value());
+       ASSERT(m_state.value() == 1); /* sync postconditions */
+       ASSERT(!m_alive);
+       m_state.down();
+       ASSERT(m_state.value() == 0);
+       
+       m_alive = 1;
+       m_started = 0;
+
+               /* start thread. */
+       pthread_attr_t attr;
+       pthread_attr_init(&attr);
+       
+       if (prio || policy)
+       {
+               struct sched_param p;
+               p.__sched_priority=prio;
+               pthread_attr_setschedpolicy(&attr, policy);
+               pthread_attr_setschedparam(&attr, &p);
+       }
+
+       if (the_thread) {
+               eDebug("old thread joined %d", pthread_join(the_thread, 0));
+               the_thread = 0;
+       }
+
+       if (pthread_create(&the_thread, &attr, wrapper, this))
+       {
+               pthread_attr_destroy(&attr);
+               m_alive = 0;
+               eDebug("couldn't create new thread");
+               return -1;
+       }
+       
+       pthread_attr_destroy(&attr);
+       return 0;
+}
+
+int eThread::run(int prio, int policy)
+{
+       if (runAsync(prio, policy))
+               return -1;
+       sync();
+       return 0;
 }
 
 eThread::~eThread()
 {
-       if (alive)
-               kill();
+       kill();
+}
+
+int eThread::sync(void)
+{
+       int res;
+       int debug_val_before = m_state.value();
+       m_state.down(); /* this might block */
+       res = m_alive;
+       if (m_state.value() != 0)
+               eFatal("eThread::sync: m_state.value() == %d - was %d before", m_state.value(), debug_val_before);
+       ASSERT(m_state.value() == 0);
+       m_state.up();
+       return res; /* 0: thread is guaranteed not to run. 1: state unknown. */
 }
 
-void eThread::kill()
+int eThread::sendSignal(int sig)
 {
-       alive=0;
-       eDebug("waiting for thread shutdown");
-       pthread_join(the_thread, 0);
-       eDebug("ok");
+       if (m_alive)
+               return pthread_kill(the_thread, sig);
+       else
+               eDebug("send signal to non running thread");
+       return -1;
+}
+
+void eThread::kill(bool sendcancel)
+{
+       if (!the_thread) /* already joined */
+               return;
+
+       if (sync() && sendcancel)
+       {
+               eDebug("send cancel to thread");
+               pthread_cancel(the_thread);
+       }
+       eDebug("thread joined %d", pthread_join(the_thread, 0));
+       the_thread = 0;
 }
 
-void eThread::sendSignal(int sig)
+void eThread::hasStarted()
 {
-       if (alive)
-               pthread_kill(the_thread, sig);
+       ASSERT(!m_state.value());
+       m_started = 1;
+       m_state.up();
 }