From db41501f230f8f29c1c32584bc4d12dfc87ce498 Mon Sep 17 00:00:00 2001
From: Uoti Urpala <uau@glyph.nonexistent.invalid>
Date: Tue, 26 Jan 2010 14:41:07 +0200
Subject: [PATCH] demux_mkv: use new EBML parser to read Audio element

---
 libmpdemux/demux_mkv.c | 66 ++++++++++++++----------------------------
 libmpdemux/ebml.c      |  3 +-
 libmpdemux/ebml.h      |  1 +
 3 files changed, 25 insertions(+), 45 deletions(-)

diff --git a/libmpdemux/demux_mkv.c b/libmpdemux/demux_mkv.c
index 288335c39c..3234171256 100644
--- a/libmpdemux/demux_mkv.c
+++ b/libmpdemux/demux_mkv.c
@@ -599,52 +599,30 @@ static int demux_mkv_read_trackencodings(demuxer_t *demuxer,
 static int demux_mkv_read_trackaudio(demuxer_t *demuxer, mkv_track_t *track)
 {
     stream_t *s = demuxer->stream;
-    uint64_t len, length, l;
-    uint64_t num;
-    double fnum;
-    int il;
 
-    track->a_sfreq = 8000.0;
-    track->a_channels = 1;
-
-    len = length = ebml_read_length(s, &il);
-    len += il;
-    while (length > 0) {
-        switch (ebml_read_id(s, &il)) {
-        case MATROSKA_ID_SAMPLINGFREQUENCY:
-            fnum = ebml_read_float(s, &l);
-            if (fnum == EBML_FLOAT_INVALID)
-                return 0;
-            track->a_sfreq = fnum;
-            mp_msg(MSGT_DEMUX, MSGL_V,
-                   "[mkv] |   + Sampling frequency: %f\n", track->a_sfreq);
-            break;
-
-        case MATROSKA_ID_BITDEPTH:
-            num = ebml_read_uint(s, &l);
-            if (num == EBML_UINT_INVALID)
-                return 0;
-            track->a_bps = num;
-            mp_msg(MSGT_DEMUX, MSGL_V, "[mkv] |   + Bit depth: %u\n",
-                   track->a_bps);
-            break;
-
-        case MATROSKA_ID_CHANNELS:
-            num = ebml_read_uint(s, &l);
-            if (num == EBML_UINT_INVALID)
-                return 0;
-            track->a_channels = num;
-            mp_msg(MSGT_DEMUX, MSGL_V, "[mkv] |   + Channels: %u\n",
-                   track->a_channels);
-            break;
-
-        default:
-            ebml_read_skip(s, &l);
-            break;
-        }
-        length -= l + il;
+    struct ebml_audio audio = {};
+    struct ebml_parse_ctx parse_ctx = {};
+    if (ebml_read_element(s, &parse_ctx, &audio, &ebml_audio_desc) < 0)
+        return 0;
+    if (audio.n_sampling_frequency) {
+        track->a_sfreq = audio.sampling_frequency;
+        mp_msg(MSGT_DEMUX, MSGL_V,
+               "[mkv] |   + Sampling frequency: %f\n", track->a_sfreq);
+    } else
+        track->a_sfreq = 8000;
+    if (audio.n_bit_depth) {
+        track->a_bps = audio.bit_depth;
+        mp_msg(MSGT_DEMUX, MSGL_V, "[mkv] |   + Bit depth: %u\n",
+               track->a_bps);
     }
-    return len;
+    if (audio.n_channels) {
+        track->a_channels = audio.channels;
+        mp_msg(MSGT_DEMUX, MSGL_V, "[mkv] |   + Channels: %u\n",
+               track->a_channels);
+    } else
+        track->a_channels = 1;
+    talloc_free(parse_ctx.talloc_ctx);
+    return parse_ctx.bytes_read;
 }
 
 static int demux_mkv_read_trackvideo(demuxer_t *demuxer, mkv_track_t *track)
diff --git a/libmpdemux/ebml.c b/libmpdemux/ebml.c
index 8bbcad4db0..ab35237a44 100644
--- a/libmpdemux/ebml.c
+++ b/libmpdemux/ebml.c
@@ -643,7 +643,7 @@ int ebml_read_element(struct stream *s, struct ebml_parse_ctx *ctx,
 {
     ctx->has_errors = false;
     int msglevel = ctx->no_error_messages ? MSGL_DBG2 : MSGL_WARN;
-    uint64_t length = ebml_read_length(s, NULL);
+    uint64_t length = ebml_read_length(s, &ctx->bytes_read);
     if (s->eof) {
         mp_msg(MSGT_DEMUX, msglevel, "[mkv] Unexpected end of file "
                    "- partial or corrupt file?\n");
@@ -656,6 +656,7 @@ int ebml_read_element(struct stream *s, struct ebml_parse_ctx *ctx,
     }
     ctx->talloc_ctx = talloc_size(NULL, length + 8);
     int read_len = stream_read(s, ctx->talloc_ctx, length);
+    ctx->bytes_read += read_len;
     if (read_len < length)
         mp_msg(MSGT_DEMUX, msglevel, "[mkv] Unexpected end of file "
                "- partial or corrupt file?\n");
diff --git a/libmpdemux/ebml.h b/libmpdemux/ebml.h
index efa3634141..b2fed46fb9 100644
--- a/libmpdemux/ebml.h
+++ b/libmpdemux/ebml.h
@@ -57,6 +57,7 @@ struct ebml_elem_desc {
 
 struct ebml_parse_ctx {
     void *talloc_ctx;
+    int bytes_read;
     bool has_errors;
     bool no_error_messages;
 };