ausrc, aufile, gst: replace duration by callback handler (baresip#3105)

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

@@ -582,13 +582,16 @@ typedef void (ausrc_error_h)(int err, const char *str, void *arg);
 typedef int  (ausrc_alloc_h)(struct ausrc_st **stp, const struct ausrc *ausrc,
 			     struct ausrc_prm *prm, const char *device,
 			     ausrc_read_h *rh, ausrc_error_h *errh, void *arg);
+typedef int  (ausrc_info_h)(const struct ausrc *ausrc,
+			    struct ausrc_prm *prm, const char *device);
 
 /** Defines an Audio Source */
 struct ausrc {
 	struct le        le;
 	const char      *name;
 	struct list      dev_list;
 	ausrc_alloc_h   *alloch;
+	ausrc_info_h    *infoh;
 };
 
 int ausrc_register(struct ausrc **asp, struct list *ausrcl, const char *name,
@@ -598,6 +601,8 @@ int ausrc_alloc(struct ausrc_st **stp, struct list *ausrcl,
 		const char *name,
 		struct ausrc_prm *prm, const char *device,
 		ausrc_read_h *rh, ausrc_error_h *errh, void *arg);
+int ausrc_info(struct list *ausrcl,
+	       const char *name, struct ausrc_prm *prm, const char *device);
 
 
 /*

modules/aufile/aufile.c

@@ -32,6 +32,10 @@ static int module_init(void)
 			     aufile_src_alloc);
 	err |= auplay_register(&auplay, baresip_auplayl(), "aufile",
 			       aufile_play_alloc);
+	if (err)
+		return err;
+
+	ausrc->infoh = aufile_info_handler;
 	return err;
 }
 

modules/aufile/aufile.h

@@ -10,3 +10,5 @@ int aufile_play_alloc(struct auplay_st **stp, const struct auplay *ap,
 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);
+int aufile_info_handler(const struct ausrc *as,
+			struct ausrc_prm *prm, const char *dev);

modules/aufile/aufile_src.c

@@ -231,7 +231,6 @@ 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;
@@ -271,3 +270,30 @@ int aufile_src_alloc(struct ausrc_st **stp, const struct ausrc *as,
 
 	return err;
 }
+
+
+int aufile_info_handler(const struct ausrc *as,
+			struct ausrc_prm *prm, const char *dev)
+{
+	int err;
+	(void)as;
+
+	if (!prm || !str_isset(dev))
+		return EINVAL;
+
+	struct aufile *aufile;
+	struct aufile_prm fprm;
+	err = aufile_open(&aufile, &fprm, dev, AUFILE_READ);
+	if (err) {
+		warning("aufile: failed to open file '%s' (%m)\n", dev, err);
+		return err;
+	}
+
+	prm->srate    = fprm.srate;
+	prm->ch       = fprm.channels;
+	prm->fmt      = fprm.fmt;
+	prm->duration = aufile_get_length(aufile, &fprm);
+
+	mem_deref(aufile);
+	return err;
+}

modules/debug_cmd/debug_cmd.c

@@ -167,27 +167,11 @@ static int cmd_play_file(struct re_printf *pf, void *arg)
 }
 
 
-struct fileinfo_st {
-	struct ausrc_st *ausrc;
-	struct ausrc_prm prm;
-	struct tmr tmr;
-};
-
-
-static void fileinfo_destruct(void *arg)
+static void print_fileinfo(struct ausrc_prm *prm)
 {
-	struct fileinfo_st *st = arg;
-
-	tmr_cancel(&st->tmr);
-	mem_deref(st->ausrc);
-}
-
+	double s  = ((float) prm->duration) / 1000;
 
-static void print_fileinfo(struct fileinfo_st *st)
-{
-	double s  = ((float) st->prm.duration) / 1000;
-
-	if (st->prm.duration) {
+	if (prm->duration) {
 		info("debug_cmd: length = %1.3lf seconds\n", s);
 		module_event("debug_cmd", "aufileinfo", NULL, NULL,
 			 "length = %lf seconds", s);
@@ -222,7 +206,7 @@ static int cmd_aufileinfo(struct re_printf *pf, void *arg)
 	char *path;
 	char aumod[16];
 	const char *file = carg->prm;
-	struct fileinfo_st *st = NULL;
+	struct ausrc_prm prm;
 
 	if (!str_isset(file)) {
 		re_hprintf(pf, "fileplay: filename not specified\n");
@@ -247,25 +231,16 @@ static int cmd_aufileinfo(struct re_printf *pf, void *arg)
 			conf_config()->audio.audio_path, file) < 0)
 		return ENOMEM;
 
-	st = mem_zalloc(sizeof(*st), fileinfo_destruct);
-	if (!st) {
-		err = ENOMEM;
-		goto out;
-	}
-
-	err = ausrc_alloc(&st->ausrc, baresip_ausrcl(),
-			  aumod,
-			  &st->prm, path, NULL, NULL, st);
+	err = ausrc_info(baresip_ausrcl(), aumod, &prm, path);
 	if (err) {
-		warning("debug_cmd: %s - ausrc %s does not support empty read "
-			"handler or reading source %s failed. (%m)\n",
-				__func__, aumod, carg->prm, err);
+		warning("debug_cmd: %s - ausrc %s does not support info query "
+			"or reading source %s failed. (%m)\n",
+			__func__, aumod, carg->prm, err);
 		goto out;
 	}
 
-	print_fileinfo(st);
+	print_fileinfo(&prm);
 out:
-	mem_deref(st);
 
 	mem_deref(path);
 	return err;

modules/gst/gst.c

@@ -345,13 +345,13 @@ static int gst_setup(struct ausrc_st *st)
 }
 
 
-static int setup_uri(struct ausrc_st *st, const char *device)
+static int setup_uri(char **urip, const char *device)
 {
 	int err = 0;
 
 	if (g_regex_match_simple(
 		uri_regex, device, 0, G_REGEX_MATCH_NOTEMPTY)) {
-		err = str_dup(&st->uri, device);
+		err = str_dup(urip, device);
 	}
 	else {
 		if (!access(device, R_OK)) {
@@ -360,7 +360,7 @@ static int setup_uri(struct ausrc_st *st, const char *device)
 			if (re_snprintf(uri, urilength, "file://%s",
 					device) < 0)
 				return ENOMEM;
-			st->uri = uri;
+			*urip = uri;
 		}
 		else {
 			err = errno;
@@ -437,7 +437,7 @@ static int gst_alloc(struct ausrc_st **stp, const struct ausrc *as,
 	st->rh   = rh;
 	st->arg  = arg;
 
-	err = setup_uri(st, device);
+	err = setup_uri(&st->uri, device);
 	if (err) goto out;
 
 	st->ptime = prm->ptime;
@@ -487,18 +487,71 @@ 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;
 	}
 
 	return err;
 }
 
 
+static int gst_info_handler(const struct ausrc *as,
+			    struct ausrc_prm *prm, const char *device)
+{
+	int err;
+	(void)as;
+
+	if (!prm || !str_isset(device))
+		return EINVAL;
+
+	GstElement *pipeline = NULL;
+	char *uri = NULL;
+	err = setup_uri(&uri, device);
+	if (err) goto out;
+
+	pipeline = gst_pipeline_new("pipeline");
+	if (!pipeline) {
+		warning("gst: failed to create pipeline element\n");
+		return ENOMEM;
+	}
+
+	GstElement *playbin = gst_element_factory_make("playbin", NULL);
+	GstElement *sink = gst_element_factory_make("fakesink", NULL);
+	if (!playbin || !sink) {
+		err = ENOMEM;
+		if (playbin)
+			gst_object_unref(playbin);
+		if (sink)
+			gst_object_unref(sink);
+		gst_object_unref(pipeline);
+		goto out;
+	}
+
+	gst_bin_add(GST_BIN(pipeline), playbin);
+	g_object_set(G_OBJECT(playbin),
+		     "uri", uri,
+		     "audio-sink", sink, NULL);
+
+	gst_element_set_state(pipeline, GST_STATE_PLAYING);
+	gst_element_get_state(pipeline, NULL, NULL, 500*1000*1000);
+	gint64 duration = 0;
+	gst_element_query_duration(pipeline,
+			    GST_FORMAT_TIME,
+			    &duration);
+
+	prm->duration = (size_t) duration / 1000000;
+
+	/* Note: other prm fields are currently not set */
+
+out:
+	if (pipeline) {
+		gst_element_set_state(pipeline, GST_STATE_NULL);
+		gst_object_unref(GST_OBJECT(pipeline));
+	}
+
+	mem_deref(uri);
+	return err;
+}
+
+
 static int mod_gst_init(void)
 {
 	gchar *s;
@@ -511,7 +564,12 @@ static int mod_gst_init(void)
 
 	g_free(s);
 
-	return ausrc_register(&ausrc, baresip_ausrcl(), "gst", gst_alloc);
+	int err = ausrc_register(&ausrc, baresip_ausrcl(), "gst", gst_alloc);
+	if (err)
+		return err;
+
+	ausrc->infoh = gst_info_handler;
+	return 0;
 }
 
 

src/ausrc.c

@@ -105,3 +105,29 @@ int ausrc_alloc(struct ausrc_st **stp, struct list *ausrcl,
 
 	return as->alloch(stp, as, prm, device, rh, errh, arg);
 }
+
+
+/**
+ * Retreive audio parameters of an audio source
+ *
+ * @param ausrcl List of Audio Sources
+ * @param name   Name of Audio Source
+ * @param prm    Audio Source parameters
+ * @param device Name of Audio Source device (driver specific)
+ *
+ * @return 0 if success, otherwise errorcode
+ */
+int ausrc_info(struct list *ausrcl,
+		const char *name, struct ausrc_prm *prm, const char *device)
+{
+	struct ausrc *as;
+
+	as = (struct ausrc *)ausrc_find(ausrcl, name);
+	if (!as)
+		return ENOENT;
+
+	if (!as->infoh)
+		return EINVAL;
+
+	return as->infoh(as, prm, device);
+}