/** @brief Lock protecting data structures
*
* This lock protects values shared between the main thread and the callback.
- * It is needed e.g. if changing @ref playing or if modifying buffer pointers.
- * It is not needed to add a new track, to read values only modified in the
- * same thread, etc.
+ *
+ * It is held 'all' the time by the main thread, the exceptions being when
+ * called activate/deactivate callbacks and when calling (potentially) slow
+ * system calls (in particular poll(), where in fact the main thread will spend
+ * most of its time blocked).
+ *
+ * The callback holds it when it's running.
*/
static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
t->id, t->eof, t->used));
if(t->eof)
return -1;
- pthread_mutex_lock(&lock);
if(t->used < sizeof t->buffer) {
/* there is room left in the buffer */
where = (t->start + t->used) % sizeof t->buffer;
rc = 0;
}
}
- pthread_mutex_unlock(&lock);
return rc;
}
memset(&sm, 0, sizeof sm);
sm.type = paused ? SM_PAUSED : SM_PLAYING;
strcpy(sm.id, playing->id);
- pthread_mutex_lock(&lock);
sm.data = playing->played / (uaudio_rate * uaudio_channels);
- pthread_mutex_unlock(&lock);
speaker_send(1, &sm);
- time(&last_report);
+ xtime(&last_report);
}
}
if(playing->start == sizeof playing->buffer)
playing->start = 0;
/* See if we've reached the end of the track */
- if(playing->used == 0 && playing->eof)
- write(sigpipe[1], "", 1);
+ if(playing->used == 0 && playing->eof) {
+ int ignored = write(sigpipe[1], "", 1);
+ (void) ignored;
+ }
provided_samples = bytes / uaudio_sample_size;
playing->played += provided_samples;
}
if(!provided_samples) {
memset(buffer, 0, max_bytes);
provided_samples = max_samples;
+ if(playing)
+ info("%zu samples silence, playing->used=%zu", provided_samples, playing->used);
+ else
+ info("%zu samples silence, playing=NULL", provided_samples);
}
pthread_mutex_unlock(&lock);
return provided_samples;
int n, fd, stdin_slot, timeout, listen_slot, sigpipe_slot;
/* Keep going while our parent process is alive */
+ pthread_mutex_lock(&lock);
while(getppid() != 1) {
int force_report = 0;
} else
t->slot = -1;
}
- sigpipe_slot = addfd(sigpipe[1], POLLIN);
+ sigpipe_slot = addfd(sigpipe[0], POLLIN);
/* Wait for something interesting to happen */
+ pthread_mutex_unlock(&lock);
n = poll(fds, fdno, timeout);
+ pthread_mutex_lock(&lock);
if(n < 0) {
if(errno == EINTR) continue;
fatal(errno, "error calling poll");
D(("SM_PLAY %s fd %d", t->id, t->fd));
if(t->fd == -1)
error(0, "cannot play track because no connection arrived");
+ /* TODO as things stand we often report this error message but then
+ * appear to proceed successfully. Understanding why requires a look
+ * at play.c: we call prepare() which makes the connection in a child
+ * process, and then sends the SM_PLAY in the parent process. The
+ * latter may well be faster. As it happens this is harmless; we'll
+ * just sit around sending silence until the decoder connects and
+ * starts sending some sample data. But is is annoying and ought to
+ * be fixed. */
pending_playing = t;
/* If nothing is currently playing then we'll switch to the pending
* track below so there's no point distinguishing the situations
D(("SM_CANCEL %s", sm.id));
t = removetrack(sm.id);
if(t) {
- pthread_mutex_lock(&lock);
if(t == playing || t == pending_playing) {
/* Scratching the track that the server believes is playing,
* which might either be the actual playing track or a pending
}
strcpy(sm.id, t->id);
destroy(t);
- pthread_mutex_unlock(&lock);
} else {
/* Probably scratching the playing track well before it's got
* going, but could indicate a bug, so we log this as an error. */
break;
case SM_RELOAD:
D(("SM_RELOAD"));
- if(config_read(1))
+ if(config_read(1, NULL))
error(0, "cannot read configuration");
info("reloaded configuration");
break;
* interrupted poll(). */
if(fds[sigpipe_slot].revents & POLLIN) {
char buffer[64];
+ int ignored; (void)ignored;
- read(sigpipe[0], buffer, sizeof buffer);
+ ignored = read(sigpipe[0], buffer, sizeof buffer);
}
/* Send SM_FINISHED when we're near the end of the track.
*
}
/* When the track is actually finished, deconfigure it */
if(playing && playing->eof && !playing->used) {
- pthread_mutex_lock(&lock);
removetrack(playing->id);
destroy(playing);
playing = 0;
- pthread_mutex_unlock(&lock);
}
/* Act on the pending SM_PLAY */
if(!playing && pending_playing) {
- pthread_mutex_lock(&lock);
playing = pending_playing;
pending_playing = 0;
- pthread_mutex_unlock(&lock);
force_report = 1;
}
/* Impose any state change required by the above */
if(playable()) {
if(!activated) {
activated = 1;
+ pthread_mutex_unlock(&lock);
backend->activate();
+ pthread_mutex_lock(&lock);
}
} else {
if(activated) {
activated = 0;
+ pthread_mutex_unlock(&lock);
backend->deactivate();
+ pthread_mutex_lock(&lock);
}
}
/* If we've not reported our state for a second do so now. */
- if(force_report || time(0) > last_report)
+ if(force_report || xtime(0) > last_report)
report();
}
}
log_default = &log_syslog;
}
config_uaudio_apis = uaudio_apis;
- if(config_read(1)) fatal(0, "cannot read configuration");
+ if(config_read(1, NULL)) fatal(0, "cannot read configuration");
/* ignore SIGPIPE */
signal(SIGPIPE, SIG_IGN);
/* set nice value */