X-Git-Url: http://git.tuebingen.mpg.de/?a=blobdiff_plain;f=ogg_afh.c;h=e2d8dbc8f9130331b2c8e2bb3523bc9e25c2a4c3;hb=3569c4ac0d5b35318e741b0123bc707473261ad9;hp=ef42c497062c228ddab10497c3388ffa2b8de90b;hpb=b62e2796b85c7d7f3138fe729f4637853e0fafe0;p=paraslash.git

diff --git a/ogg_afh.c b/ogg_afh.c
index ef42c497..e2d8dbc8 100644
--- a/ogg_afh.c
+++ b/ogg_afh.c
@@ -21,7 +21,7 @@ struct private_vorbis_data {
 };
 
 static int vorbis_packet_callback(ogg_packet *packet, int packet_num,
-		struct afh_info *afhi, void *private_data)
+		__a_unused int serial, struct afh_info *afhi, void *private_data)
 {
 	struct private_vorbis_data *pvd = private_data;
 
@@ -65,6 +65,118 @@ static int ogg_vorbis_get_file_info(char *map, size_t numbytes, __a_unused int f
 	return ret;
 }
 
+struct vorbis_get_header_data {
+	ogg_stream_state os;
+	char *buf;
+	size_t len;
+};
+
+static void add_ogg_page(ogg_page *og, struct vorbis_get_header_data *vghd)
+{
+	size_t old_len = vghd->len;
+	size_t new_len = vghd->len + og->header_len + og->body_len;
+	char *buf = para_realloc(vghd->buf, new_len), *p = buf + old_len;
+
+	memcpy(p, og->header, og->header_len);
+	memcpy(p + og->header_len, og->body, og->body_len);
+	vghd->buf = buf;
+	vghd->len = new_len;
+	PARA_DEBUG_LOG("header/body/old/new: %lu/%lu/%zu/%zu\n",
+		og->header_len, og->body_len, old_len, new_len);
+}
+
+/*
+ * Process the first three ogg packets.
+ *
+ * This creates chunk zero (the audio file header) from the first three ogg
+ * packets of the input file with metadata (vorbis comments) stripped off. Page
+ * 0 of the input file always contains only ogg packet #0 while page 1 usually
+ * contains both packets 1 (comments) and 2 (setup).  However, we always create
+ * an separate ogg page for each packet to circumvent a bug in older libogg
+ * versions which causes too little data being copied to the second ogg page.
+ * This affects at least Ubuntu Hardy, and there is no real disadvantage in
+ * creating three pages instead of two.
+ */
+static int vorbis_get_header_callback(ogg_packet *packet, int packet_num,
+		int serial, __a_unused struct afh_info *afhi, void *private_data)
+{
+	int ret;
+	struct vorbis_get_header_data *vghd = private_data;
+	ogg_page og;
+	static unsigned char dummy_packet[] = {
+		0x03,
+		'v', 'o', 'r', 'b', 'i', 's',
+		0x06, 0x00, 0x00, 0x00,
+		'd', 'u', 'm', 'm', 'y', '\0',
+		0x00, 0x00, 0x00, 0x00, /* no comment :) */
+		0xff /* framing bit */
+	};
+
+	PARA_DEBUG_LOG("processing ogg packet #%d (%li bytes)\n",
+		packet_num, packet->bytes);
+	if (packet_num > 2)
+		return 0;
+	if (packet_num == 0) {
+		ogg_stream_init(&vghd->os, serial);
+		ret = -E_OGG_PACKET_IN;
+		ret = ogg_stream_packetin(&vghd->os, packet);
+		if (ret < 0)
+			goto out;
+		ret = -E_OGG_STREAM_FLUSH;
+		if (ogg_stream_flush(&vghd->os, &og) == 0)
+			goto out;
+		add_ogg_page(&og, vghd);
+		return 1;
+	}
+	if (packet_num == 1) {
+		PARA_INFO_LOG("replacing metadata packet (saved %ld bytes)\n",
+			packet->bytes - sizeof(dummy_packet));
+		ogg_packet replacement = *packet;
+		replacement.packet = dummy_packet;
+		replacement.bytes = sizeof(dummy_packet);
+		ret = -E_OGG_PACKET_IN;
+		if (ogg_stream_packetin(&vghd->os, &replacement) < 0)
+			goto out;
+		ret = -E_OGG_STREAM_FLUSH;
+		if (ogg_stream_flush(&vghd->os, &og) == 0)
+			goto out;
+		add_ogg_page(&og, vghd);
+		return 1;
+	}
+	ret = -E_OGG_PACKET_IN;
+	if (ogg_stream_packetin(&vghd->os, packet) < 0)
+		goto out;
+	ret = -E_OGG_STREAM_FLUSH;
+	if (ogg_stream_flush(&vghd->os, &og) == 0)
+		goto out;
+	add_ogg_page(&og, vghd);
+	ret = 0;
+out:
+	ogg_stream_clear(&vghd->os);
+	return ret;
+}
+
+static void vorbis_get_header(void *map, size_t mapsize, char **buf,
+		size_t *len)
+{
+	int ret;
+	struct vorbis_get_header_data vghd = {.len = 0};
+	struct ogg_afh_callback_info cb = {
+		.packet_callback = vorbis_get_header_callback,
+		.private_data = &vghd,
+	};
+
+	ret = ogg_get_file_info(map, mapsize, NULL, &cb);
+	if (ret < 0)
+		goto fail;
+	*buf = vghd.buf;
+	*len = vghd.len;
+	PARA_INFO_LOG("created %zu byte ogg/vorbis header chunk\n", *len);
+	return;
+fail:
+	PARA_ERROR_LOG("%s\n", para_strerror(-ret));
+}
+
 static const char* ogg_suffixes[] = {"ogg", NULL};
 
 /**
@@ -74,6 +186,7 @@ static const char* ogg_suffixes[] = {"ogg", NULL};
  */
 void ogg_init(struct audio_format_handler *afh)
 {
-	afh->get_file_info = ogg_vorbis_get_file_info,
+	afh->get_file_info = ogg_vorbis_get_file_info;
+	afh->get_header = vorbis_get_header;
 	afh->suffixes = ogg_suffixes;
 }