shout: added shout_buffer

The Ogg encoder is slightly less optimal under this configuration.  It
used to send shout data directly out of its ogg_page structures.  Now,
in the interest of encapsulation, it copies the data from its ogg_page
structures into a buffer provided by the shout audio output plugin
(see audioOutput_shout_ogg.c, line 77.)  I suspect the performance
impact is negligible.

[mk: this patch and its description was separated from Eric's patch
"Refactor and cleanup of shout Ogg and MP3 audio outputs"]

src/audioOutputs/audioOutput_shout.c

@@ -25,8 +25,16 @@
 #define CONN_ATTEMPT_INTERVAL 60
 #define DEFAULT_CONN_TIMEOUT  2
 
+#define SHOUT_BUF_SIZE 8192
+
 static int shout_init_count;
 
+static void clear_shout_buffer(struct shout_data * sd)
+{
+	sd->buf.len = 0;
+	sd->buf.data[0] = '\0';
+}
+
 static struct shout_data *new_shout_data(void)
 {
 	struct shout_data *ret = xmalloc(sizeof(*ret));
@@ -41,6 +49,10 @@ static struct shout_data *new_shout_data(void)
 	ret->conn_attempts = 0;
 	ret->last_attempt = 0;
 	ret->timer = NULL;
+	ret->buf.data = xmalloc(sizeof(unsigned char) *
+				SHOUT_BUF_SIZE);
+	ret->buf.max_len = SHOUT_BUF_SIZE;
+	clear_shout_buffer(ret);
 
 	return ret;
 }
@@ -51,6 +63,8 @@ static void free_shout_data(struct shout_data *sd)
 		shout_free(sd->shout_conn);
 	if (sd->tag)
 		tag_free(sd->tag);
+	if (sd->buf.data)
+		free(sd->buf.data);
 	if (sd->timer)
 		timer_free(sd->timer);
 
@@ -248,25 +262,25 @@ static int handle_shout_error(struct shout_data *sd, int err)
 	return 0;
 }
 
-int write_page(struct shout_data *sd)
+static int write_page(struct shout_data *sd)
 {
 	int err;
 
 	shout_sync(sd->shout_conn);
-	err = shout_send(sd->shout_conn, sd->og.header, sd->og.header_len);
+	err = shout_send(sd->shout_conn, sd->buf.data, sd->buf.len);
-	if (handle_shout_error(sd, err) < 0)
-		return -1;
-	err = shout_send(sd->shout_conn, sd->og.body, sd->og.body_len);
 	if (handle_shout_error(sd, err) < 0)
 		return -1;
+	clear_shout_buffer(sd);
 
 	return 0;
 }
 
 static void close_shout_conn(struct shout_data *sd)
 {
-	if (sd->opened)
+	if (sd->opened) {
-		shout_ogg_encoder_clear_encoder(sd);
+		if (shout_ogg_encoder_clear_encoder(sd))
+			write_page(sd);
+	}
 
 	if (shout_get_connected(sd->shout_conn) != SHOUTERR_UNCONNECTED &&
 	    shout_close(sd->shout_conn) != SHOUTERR_SUCCESS) {
@@ -383,22 +397,12 @@ static int open_shout_conn(struct audio_output *audio_output)
 		return -1;
 	}
 
+	if (sd->buf.len)
+		write_page(sd);
+
 	sd->shout_error = 0;
-
-	copy_tag_to_vorbis_comment(sd);
-
-	send_ogg_vorbis_header(sd);
-
 	sd->opened = 1;
-	sd->tag_to_send = 0;
+	sd->tag_to_send = 1;
-
-	while (ogg_stream_flush(&(sd->os), &(sd->og))) {
-		if (write_page(sd) < 0) {
-			close_shout_conn(sd);
-			return -1;
-		}
-	}
-
 	sd->conn_attempts = 0;
 
 	return 0;
@@ -461,12 +465,10 @@ static int my_shout_play(struct audio_output *audio_output,
 
 	shout_ogg_encoder_encode(sd, chunk, size);
 
-	while (ogg_stream_pageout(&(sd->os), &(sd->og)) != 0) {
 	if (write_page(sd) < 0) {
 		my_shout_close_device(audio_output);
 		return -1;
 	}
-	}
 
 	return 0;
 }

src/audioOutputs/audioOutput_shout.h

@@ -29,6 +29,12 @@
 #include <shout/shout.h>
 #include <vorbis/vorbisenc.h>
 
+typedef struct _shout_buffer {
+	unsigned char *data;
+	size_t len;
+	size_t max_len;
+} shout_buffer;
+
 struct shout_data {
 	shout_t *shout_conn;
 	int shout_error;
@@ -61,15 +67,15 @@ struct shout_data {
 
 	/* the configured audio format */
 	struct audio_format audio_format;
-};
 
-int write_page(struct shout_data *sd);
+	shout_buffer buf;
+};
 
 void copy_tag_to_vorbis_comment(struct shout_data *sd);
 
-void send_ogg_vorbis_header(struct shout_data *sd);
+int send_ogg_vorbis_header(struct shout_data *sd);
 
-void shout_ogg_encoder_clear_encoder(struct shout_data *sd);
+int shout_ogg_encoder_clear_encoder(struct shout_data *sd);
 
 int init_encoder(struct shout_data *sd);
 

src/audioOutputs/audioOutput_shout_ogg.c

@@ -54,7 +54,42 @@ void copy_tag_to_vorbis_comment(struct shout_data *sd)
 	}
 }
 
-void send_ogg_vorbis_header(struct shout_data *sd)
+static int copy_ogg_buffer_to_shout_buffer(ogg_page *og,
+					   shout_buffer *buf)
+{
+	if (buf->max_len - buf->len >= (size_t)og->header_len) {
+		memcpy(buf->data + buf->len,
+		       og->header, og->header_len);
+		buf->len += og->header_len;
+	} else {
+		ERROR("%s: not enough buffer space!\n", __func__);
+		return -1;
+	}
+
+	if (buf->max_len - buf->len >= (size_t)og->body_len) {
+		memcpy(buf->data + buf->len,
+		       og->body, og->body_len);
+		buf->len += og->body_len;
+	} else {
+		ERROR("%s: not enough buffer space!\n", __func__);
+		return -1;
+	}
+
+	return 0;
+}
+
+static int flush_ogg_buffer(struct shout_data *sd)
+{
+	shout_buffer *buf = &sd->buf;
+	int ret = 0;
+
+	if (ogg_stream_flush(&sd->os, &sd->og))
+		ret = copy_ogg_buffer_to_shout_buffer(&sd->og, buf);
+
+	return ret;
+}
+
+int send_ogg_vorbis_header(struct shout_data *sd)
 {
 	vorbis_analysis_headerout(&(sd->vd), &(sd->vc), &(sd->header_main),
 				  &(sd->header_comments),
@@ -63,6 +98,8 @@ void send_ogg_vorbis_header(struct shout_data *sd)
 	ogg_stream_packetin(&(sd->os), &(sd->header_main));
 	ogg_stream_packetin(&(sd->os), &(sd->header_comments));
 	ogg_stream_packetin(&(sd->os), &(sd->header_codebooks));
+
+	return flush_ogg_buffer(sd);
 }
 
 static void finish_encoder(struct shout_data *sd)
@@ -78,27 +115,24 @@ static void finish_encoder(struct shout_data *sd)
 	}
 }
 
-static int flush_encoder(struct shout_data *sd)
+int shout_ogg_encoder_clear_encoder(struct shout_data *sd)
 {
-	return (ogg_stream_pageout(&sd->os, &sd->og) > 0);
+	int ret;
-}
 
-void shout_ogg_encoder_clear_encoder(struct shout_data *sd)
-{
 	finish_encoder(sd);
-	while (1 == flush_encoder(sd)) {
+	if ((ret = ogg_stream_pageout(&sd->os, &sd->og)))
-		if (!sd->shout_error)
+		copy_ogg_buffer_to_shout_buffer(&sd->og, &sd->buf);
-			write_page(sd);
-	}
 
 	vorbis_comment_clear(&sd->vc);
 	ogg_stream_clear(&sd->os);
 	vorbis_block_clear(&sd->vb);
 	vorbis_dsp_clear(&sd->vd);
 	vorbis_info_clear(&sd->vi);
+
+	return ret;
 }
 
-int init_encoder(struct shout_data *sd)
+static int reinit_encoder(struct shout_data *sd)
 {
 	vorbis_info_init(&(sd->vi));
 
@@ -130,10 +164,23 @@ int init_encoder(struct shout_data *sd)
 	return 0;
 }
 
+int init_encoder(struct shout_data *sd)
+{
+	if (reinit_encoder(sd))
+		return -1;
+
+	if (send_ogg_vorbis_header(sd)) {
+		ERROR("error sending ogg vorbis header for shout\n");
+		return -1;
+	}
+
+	return 0;
+}
+
 int shout_ogg_encoder_send_metadata(struct shout_data * sd)
 {
 	shout_ogg_encoder_clear_encoder(sd);
-	if (init_encoder(sd) < 0)
+	if (reinit_encoder(sd))
 		return 0;
 
 	copy_tag_to_vorbis_comment(sd);
@@ -146,10 +193,7 @@ int shout_ogg_encoder_send_metadata(struct shout_data * sd)
 	ogg_stream_packetin(&(sd->os), &(sd->header_comments));
 	ogg_stream_packetin(&(sd->os), &(sd->header_codebooks));
 
-	while (ogg_stream_flush(&sd->os, &sd->og)) {
+	flush_ogg_buffer(sd);
-		if (write_page(sd) < 0)
-			return -1;
-	}
 
 	return 0;
 }
@@ -157,6 +201,7 @@ int shout_ogg_encoder_send_metadata(struct shout_data * sd)
 void shout_ogg_encoder_encode(struct shout_data *sd,
 			      const char *chunk, size_t size)
 {
+	shout_buffer *buf = &sd->buf;
 	unsigned int i;
 	int j;
 	float **vorbbuf;
@@ -185,6 +230,9 @@ void shout_ogg_encoder_encode(struct shout_data *sd,
 			ogg_stream_packetin(&(sd->os), &(sd->op));
 		}
 	}
+
+	if (ogg_stream_pageout(&sd->os, &sd->og))
+		copy_ogg_buffer_to_shout_buffer(&sd->og, buf);
 }
 
 #endif