afh_recv: Improve documentation of --begin-chunk.

[paraslash.git] / ogg_afh.c

diff --git a/ogg_afh.c b/ogg_afh.c
index e2d8dbc8f9130331b2c8e2bb3523bc9e25c2a4c3..32f8bc1beda6f10376db3d3842e0e3cfcaf02e96 100644 (file)
--- a/ogg_afh.c
+++ b/ogg_afh.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2004-2011 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2004 Andre Noll <maan@tuebingen.mpg.de>
  *
  * Licensed under the GPL v2. For licencing details see COPYING.
  */
@@ -20,6 +20,20 @@ struct private_vorbis_data {
        vorbis_comment vc;
 };
 
+/*
+ * Vorbis uses three header packets, all of which are required: the
+ * identification header, the comments header, and the setup header.
+ *
+ * The identification header identifies the bitstream as Vorbis. It contains
+ * the Vorbis version and simple audio characteristics of the stream such as
+ * sample rate and number of channels.
+ *
+ * The comment header includes user text comments (tags) and a vendor string
+ * for the application/library that produced the bitstream.
+ *
+ * The setup header includes extensive CODEC setup information as well as the
+ * complete VQ and Huffman codebooks needed for decoding.
+ */
 static int vorbis_packet_callback(ogg_packet *packet, int packet_num,
                __a_unused int serial, struct afh_info *afhi, void *private_data)
 {
@@ -85,18 +99,6 @@ static void add_ogg_page(ogg_page *og, struct vorbis_get_header_data *vghd)
                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)
 {
@@ -112,13 +114,11 @@ static int vorbis_get_header_callback(ogg_packet *packet, int packet_num,
                0xff /* framing bit */
        };
 
-       PARA_DEBUG_LOG("processing ogg packet #%d (%li bytes)\n",
-               packet_num, packet->bytes);
+       PARA_DEBUG_LOG("processing ogg packet #%d\n", packet_num);
        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;
@@ -129,27 +129,21 @@ static int vorbis_get_header_callback(ogg_packet *packet, int packet_num,
                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;
+               PARA_INFO_LOG("replacing metadata packet\n");
                replacement.packet = dummy_packet;
                replacement.bytes = sizeof(dummy_packet);
+               ret = ogg_stream_packetin(&vghd->os, &replacement);
+               if (ret >= 0)
+                       return 1;
                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;
+               goto out;
        }
        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);
+       while (ogg_stream_flush(&vghd->os, &og))
+               add_ogg_page(&og, vghd);
        ret = 0;
 out:
        ogg_stream_clear(&vghd->os);
@@ -171,7 +165,7 @@ static void vorbis_get_header(void *map, size_t mapsize, char **buf,
                goto fail;
        *buf = vghd.buf;
        *len = vghd.len;
-       PARA_INFO_LOG("created %zu byte ogg/vorbis header chunk\n", *len);
+       PARA_INFO_LOG("created %zu byte ogg vorbis header\n", *len);
        return;
 fail:
        PARA_ERROR_LOG("%s\n", para_strerror(-ret));
@@ -179,6 +173,39 @@ fail:
 
 static const char* ogg_suffixes[] = {"ogg", NULL};
 
+static int vorbis_make_meta_packet(struct taginfo *tags, ogg_packet *result)
+{
+       vorbis_comment vc;
+       int ret;
+
+       vorbis_comment_init(&vc);
+       vorbis_comment_add_tag(&vc, "artist", tags->artist);
+       vorbis_comment_add_tag(&vc, "title", tags->title);
+       vorbis_comment_add_tag(&vc, "album", tags->album);
+       vorbis_comment_add_tag(&vc, "year", tags->year);
+       vorbis_comment_add_tag(&vc, "comment", tags->comment);
+       ret = vorbis_commentheader_out(&vc, result);
+       vorbis_comment_clear(&vc);
+       if (ret != 0)
+               return -E_VORBIS_COMMENTHEADER;
+       return 1;
+}
+
+static int vorbis_rewrite_tags(const char *map, size_t mapsize,
+               struct taginfo *tags, int output_fd,
+               __a_unused const char *filename)
+{
+       int ret;
+       ogg_packet packet;
+
+       ret = vorbis_make_meta_packet(tags, &packet);
+       if (ret < 0)
+               return ret;
+       ret = ogg_rewrite_tags(map, mapsize, output_fd, (char *)packet.packet,
+               packet.bytes);
+       free(packet.packet);
+       return ret;
+}
 /**
  * The init function of the ogg vorbis audio format handler.
  *
@@ -189,4 +216,5 @@ void ogg_init(struct audio_format_handler *afh)
        afh->get_file_info = ogg_vorbis_get_file_info;
        afh->get_header = vorbis_get_header;
        afh->suffixes = ogg_suffixes;
+       afh->rewrite_tags = vorbis_rewrite_tags;
 }