ausrc, aufile, gst: replace duration by callback handler

Retrieving the duration of an audio file may lead to long blocking
delay. E.g. gst_element_query_duration()
Now a callback handler can be called by the application only if
needed.

include/baresip.h

@@ -565,14 +565,15 @@ int message_encode_dict(struct odict *od, struct account *acc,
 
 struct ausrc;
 struct ausrc_st;
+typedef size_t (ausrc_duration_h)(struct ausrc_st *st);
 
 /** Audio Source parameters */
 struct ausrc_prm {
 	uint32_t   srate;       /**< Sampling rate in [Hz]      */
 	uint8_t    ch;          /**< Number of channels         */
 	uint32_t   ptime;       /**< Wanted packet-time in [ms] */
 	int        fmt;         /**< Sample format (enum aufmt) */
-	size_t     duration;    /**< Duration in [ms], 0 for infinite        */
+	ausrc_duration_h *durationh;  /**< Handler returns duration in [ms]  */
 };
 
 typedef void (ausrc_read_h)(struct auframe *af, void *arg);

modules/aufile/aufile_src.c

@@ -31,6 +31,7 @@ struct ausrc_st {
 	struct aubuf *aubuf;
 	enum aufmt fmt;                 /**< Wav file sample format          */
 	struct ausrc_prm prm;           /**< Audio src parameter             */
+	struct aufile_prm fprm;
 	uint32_t ptime;
 	size_t sampc;
 	RE_ATOMIC bool run;
@@ -189,6 +190,16 @@ static int read_file(struct ausrc_st *st)
 }
 
 
+static size_t aufile_duration_handler(struct ausrc_st *st)
+{
+	if (!st)
+		return 0;
+
+
+	return aufile_get_length(st->aufile, &st->fprm);
+}
+
+
 int aufile_src_alloc(struct ausrc_st **stp, const struct ausrc *as,
 		     struct ausrc_prm *prm, const char *dev,
 		     ausrc_read_h *rh, ausrc_error_h *errh, void *arg)
@@ -231,7 +242,6 @@ int aufile_src_alloc(struct ausrc_st **stp, const struct ausrc *as,
 	/* return wav format to caller */
 	prm->srate = fprm.srate;
 	prm->ch    = fprm.channels;
-	prm->duration = aufile_get_length(st->aufile, &fprm);
 
 	if (!rh)
 		goto out;
@@ -266,8 +276,11 @@ int aufile_src_alloc(struct ausrc_st **stp, const struct ausrc *as,
  out:
 	if (err)
 		mem_deref(st);
-	else
+	else {
 		*stp = st;
+		st->fprm = fprm;
+		prm->durationh = aufile_duration_handler;
+	}
 
 	return err;
 }

modules/debug_cmd/debug_cmd.c

@@ -185,9 +185,12 @@ static void fileinfo_destruct(void *arg)
 
 static void print_fileinfo(struct fileinfo_st *st)
 {
-	double s  = ((float) st->prm.duration) / 1000;
+	size_t duration = 0;
+	if (st->prm.durationh)
+		duration = st->prm.durationh(st->ausrc);
 
-	if (st->prm.duration) {
+	if (duration) {
+		double s  = ((float) duration) / 1000;
 		info("debug_cmd: length = %1.3lf seconds\n", s);
 		module_event("debug_cmd", "aufileinfo", NULL, NULL,
 			 "length = %lf seconds", s);

modules/gst/gst.c

@@ -411,6 +411,21 @@ static void timeout(void *arg)
 }
 
 
+static size_t gst_duration_handler(struct ausrc_st *st)
+{
+	if (!st)
+		return 0;
+
+	gst_element_get_state(st->pipeline, NULL, NULL, 500*1000*1000);
+	gint64 duration = 0;
+	gst_element_query_duration(st->pipeline,
+			    GST_FORMAT_TIME,
+			    &duration);
+
+	return duration / 1000000;
+}
+
+
 static int gst_alloc(struct ausrc_st **stp, const struct ausrc *as,
 		     struct ausrc_prm *prm, const char *device,
 		     ausrc_read_h *rh, ausrc_error_h *errh, void *arg)
@@ -487,12 +502,7 @@ static int gst_alloc(struct ausrc_st **stp, const struct ausrc *as,
 		mem_deref(st);
 	else {
 		*stp = st;
-		gst_element_get_state(st->pipeline, NULL, NULL, 500*1000*1000);
-		gint64 duration = 0;
-		gst_element_query_duration(st->pipeline,
-				   	   GST_FORMAT_TIME,
-				   	   &duration);
-		prm->duration = duration / 1000000;
+		prm->durationh = gst_duration_handler;
 	}
 
 	return err;