]> git.sesse.net Git - ffmpeg/blobdiff - libavformat/matroskadec.c
Cosmetics: Fix comment.
[ffmpeg] / libavformat / matroskadec.c
index f3d7a2d2d01fd619fc222c412045f7ca5678a185..9cf3e956fc609aabb24d0cffb04c038c3cb0625b 100644 (file)
@@ -255,6 +255,9 @@ typedef struct {
     /* What to skip before effectively reading a packet. */
     int skip_to_keyframe;
     uint64_t skip_to_timecode;
+
+    /* File has a CUES element, but we defer parsing until it is needed. */
+    int cues_parsing_deferred;
 } MatroskaDemuxContext;
 
 typedef struct {
@@ -826,11 +829,15 @@ static int ebml_parse_elem(MatroskaDemuxContext *matroska,
     uint32_t id = syntax->id;
     uint64_t length;
     int res;
+    void *newelem;
 
     data = (char *)data + syntax->data_offset;
     if (syntax->list_elem_size) {
         EbmlList *list = data;
-        list->elem = av_realloc(list->elem, (list->nb_elem+1)*syntax->list_elem_size);
+        newelem = av_realloc(list->elem, (list->nb_elem+1)*syntax->list_elem_size);
+        if (!newelem)
+            return AVERROR(ENOMEM);
+        list->elem = newelem;
         data = (char*)list->elem + list->nb_elem*syntax->list_elem_size;
         memset(data, 0, syntax->list_elem_size);
         list->nb_elem++;
@@ -928,6 +935,8 @@ static int matroska_probe(AVProbeData *p)
      * Not fully fool-proof, but good enough. */
     for (i = 0; i < FF_ARRAY_ELEMS(matroska_doctypes); i++) {
         int probelen = strlen(matroska_doctypes[i]);
+        if (total < probelen)
+            continue;
         for (n = 4+size; n <= 4+size+total-probelen; n++)
             if (!memcmp(p->buf+n, matroska_doctypes[i], probelen))
                 return AVPROBE_SCORE_MAX;
@@ -990,7 +999,10 @@ static int matroska_decode_buffer(uint8_t** buf, int* buf_size,
             pkt_data = av_realloc(pkt_data, pkt_size);
             zstream.avail_out = pkt_size - zstream.total_out;
             zstream.next_out = pkt_data + zstream.total_out;
-            result = inflate(&zstream, Z_NO_FLUSH);
+            if (pkt_data) {
+                result = inflate(&zstream, Z_NO_FLUSH);
+            } else
+                result = Z_MEM_ERROR;
         } while (result==Z_OK && pkt_size<10000000);
         pkt_size = zstream.total_out;
         inflateEnd(&zstream);
@@ -1011,7 +1023,10 @@ static int matroska_decode_buffer(uint8_t** buf, int* buf_size,
             pkt_data = av_realloc(pkt_data, pkt_size);
             bzstream.avail_out = pkt_size - bzstream.total_out_lo32;
             bzstream.next_out = pkt_data + bzstream.total_out_lo32;
-            result = BZ2_bzDecompress(&bzstream);
+            if (pkt_data) {
+                result = BZ2_bzDecompress(&bzstream);
+            } else
+                result = BZ_MEM_ERROR;
         } while (result==BZ_OK && pkt_size<10000000);
         pkt_size = bzstream.total_out_lo32;
         BZ2_bzDecompressEnd(&bzstream);
@@ -1064,13 +1079,17 @@ static void matroska_fix_ass_packet(MatroskaDemuxContext *matroska,
     }
 }
 
-static void matroska_merge_packets(AVPacket *out, AVPacket *in)
+static int matroska_merge_packets(AVPacket *out, AVPacket *in)
 {
-    out->data = av_realloc(out->data, out->size+in->size);
+    void *newdata = av_realloc(out->data, out->size+in->size);
+    if (!newdata)
+        return AVERROR(ENOMEM);
+    out->data = newdata;
     memcpy(out->data+out->size, in->data, in->size);
     out->size += in->size;
     av_destruct_packet(in);
     av_free(in);
+    return 0;
 }
 
 static void matroska_convert_tag(AVFormatContext *s, EbmlList *list,
@@ -1139,7 +1158,7 @@ static void matroska_convert_tags(AVFormatContext *s)
     }
 }
 
-static void matroska_execute_seekhead(MatroskaDemuxContext *matroska)
+static int matroska_parse_seekhead_entry(MatroskaDemuxContext *matroska, int idx)
 {
     EbmlList *seekhead_list = &matroska->seekhead;
     MatroskaSeekhead *seekhead = seekhead_list->elem;
@@ -1147,6 +1166,54 @@ static void matroska_execute_seekhead(MatroskaDemuxContext *matroska)
     int64_t before_pos = avio_tell(matroska->ctx->pb);
     uint32_t saved_id = matroska->current_id;
     MatroskaLevel level;
+    int64_t offset;
+    int ret = 0;
+
+    if (idx >= seekhead_list->nb_elem
+            || seekhead[idx].id == MATROSKA_ID_SEEKHEAD
+            || seekhead[idx].id == MATROSKA_ID_CLUSTER)
+        return 0;
+
+    /* seek */
+    offset = seekhead[idx].pos + matroska->segment_start;
+    if (avio_seek(matroska->ctx->pb, offset, SEEK_SET) == offset) {
+        /* We don't want to lose our seekhead level, so we add
+         * a dummy. This is a crude hack. */
+        if (matroska->num_levels == EBML_MAX_DEPTH) {
+            av_log(matroska->ctx, AV_LOG_INFO,
+                   "Max EBML element depth (%d) reached, "
+                   "cannot parse further.\n", EBML_MAX_DEPTH);
+            ret = AVERROR_INVALIDDATA;
+        } else {
+            level.start = 0;
+            level.length = (uint64_t)-1;
+            matroska->levels[matroska->num_levels] = level;
+            matroska->num_levels++;
+            matroska->current_id = 0;
+
+            ebml_parse(matroska, matroska_segment, matroska);
+
+            /* remove dummy level */
+            while (matroska->num_levels) {
+                uint64_t length = matroska->levels[--matroska->num_levels].length;
+                if (length == (uint64_t)-1)
+                    break;
+            }
+        }
+    }
+    /* seek back */
+    avio_seek(matroska->ctx->pb, before_pos, SEEK_SET);
+    matroska->level_up = level_up;
+    matroska->current_id = saved_id;
+
+    return ret;
+}
+
+static void matroska_execute_seekhead(MatroskaDemuxContext *matroska)
+{
+    EbmlList *seekhead_list = &matroska->seekhead;
+    MatroskaSeekhead *seekhead = seekhead_list->elem;
+    int64_t before_pos = avio_tell(matroska->ctx->pb);
     int i;
 
     // we should not do any seeking in the streaming case
@@ -1154,47 +1221,55 @@ static void matroska_execute_seekhead(MatroskaDemuxContext *matroska)
         (matroska->ctx->flags & AVFMT_FLAG_IGNIDX))
         return;
 
-    for (i=0; i<seekhead_list->nb_elem; i++) {
-        int64_t offset = seekhead[i].pos + matroska->segment_start;
-
-        if (seekhead[i].pos <= before_pos
-            || seekhead[i].id == MATROSKA_ID_SEEKHEAD
-            || seekhead[i].id == MATROSKA_ID_CLUSTER)
+    for (i = 0; i < seekhead_list->nb_elem; i++) {
+        if (seekhead[i].pos <= before_pos)
             continue;
 
-        /* seek */
-        if (avio_seek(matroska->ctx->pb, offset, SEEK_SET) != offset)
+        // defer cues parsing until we actually need cue data.
+        if (seekhead[i].id == MATROSKA_ID_CUES) {
+            matroska->cues_parsing_deferred = 1;
             continue;
+        }
 
-        /* We don't want to lose our seekhead level, so we add
-         * a dummy. This is a crude hack. */
-        if (matroska->num_levels == EBML_MAX_DEPTH) {
-            av_log(matroska->ctx, AV_LOG_INFO,
-                   "Max EBML element depth (%d) reached, "
-                   "cannot parse further.\n", EBML_MAX_DEPTH);
+        if (matroska_parse_seekhead_entry(matroska, i) < 0)
             break;
-        }
+    }
+}
 
-        level.start = 0;
-        level.length = (uint64_t)-1;
-        matroska->levels[matroska->num_levels] = level;
-        matroska->num_levels++;
-        matroska->current_id = 0;
+static void matroska_parse_cues(MatroskaDemuxContext *matroska) {
+    EbmlList *seekhead_list = &matroska->seekhead;
+    MatroskaSeekhead *seekhead = seekhead_list->elem;
+    EbmlList *index_list;
+    MatroskaIndex *index;
+    int index_scale = 1;
+    int i, j;
 
-        ebml_parse(matroska, matroska_segment, matroska);
+    for (i = 0; i < seekhead_list->nb_elem; i++)
+        if (seekhead[i].id == MATROSKA_ID_CUES)
+            break;
+    assert(i <= seekhead_list->nb_elem);
 
-        /* remove dummy level */
-        while (matroska->num_levels) {
-            uint64_t length = matroska->levels[--matroska->num_levels].length;
-            if (length == (uint64_t)-1)
-                break;
+    matroska_parse_seekhead_entry(matroska, i);
+
+    index_list = &matroska->index;
+    index = index_list->elem;
+    if (index_list->nb_elem
+        && index[0].time > 1E14/matroska->time_scale) {
+        av_log(matroska->ctx, AV_LOG_WARNING, "Working around broken index.\n");
+        index_scale = matroska->time_scale;
+    }
+    for (i = 0; i < index_list->nb_elem; i++) {
+        EbmlList *pos_list = &index[i].pos;
+        MatroskaIndexPos *pos = pos_list->elem;
+        for (j = 0; j < pos_list->nb_elem; j++) {
+            MatroskaTrack *track = matroska_find_track_by_num(matroska, pos[j].track);
+            if (track && track->stream)
+                av_add_index_entry(track->stream,
+                                   pos[j].pos + matroska->segment_start,
+                                   index[i].time/index_scale, 0, 0,
+                                   AVINDEX_KEYFRAME);
         }
     }
-
-    /* seek back */
-    avio_seek(matroska->ctx->pb, before_pos, SEEK_SET);
-    matroska->level_up = level_up;
-    matroska->current_id = saved_id;
 }
 
 static int matroska_aac_profile(char *codec_id)
@@ -1226,9 +1301,6 @@ static int matroska_read_header(AVFormatContext *s, AVFormatParameters *ap)
     EbmlList *chapters_list = &matroska->chapters;
     MatroskaChapter *chapters;
     MatroskaTrack *tracks;
-    EbmlList *index_list;
-    MatroskaIndex *index;
-    int index_scale = 1;
     uint64_t max_start = 0;
     Ebml ebml = { 0 };
     AVStream *st;
@@ -1276,7 +1348,7 @@ static int matroska_read_header(AVFormatContext *s, AVFormatParameters *ap)
     for (i=0; i < matroska->tracks.nb_elem; i++) {
         MatroskaTrack *track = &tracks[i];
         enum CodecID codec_id = CODEC_ID_NONE;
-        EbmlList *encodings_list = &tracks->encodings;
+        EbmlList *encodings_list = &track->encodings;
         MatroskaTrackEncoding *encodings = encodings_list->elem;
         uint8_t *extradata = NULL;
         int extradata_size = 0;
@@ -1587,27 +1659,6 @@ static int matroska_read_header(AVFormatContext *s, AVFormatParameters *ap)
             max_start = chapters[i].start;
         }
 
-    index_list = &matroska->index;
-    index = index_list->elem;
-    if (index_list->nb_elem
-        && index[0].time > 100000000000000/matroska->time_scale) {
-        av_log(matroska->ctx, AV_LOG_WARNING, "Working around broken index.\n");
-        index_scale = matroska->time_scale;
-    }
-    for (i=0; i<index_list->nb_elem; i++) {
-        EbmlList *pos_list = &index[i].pos;
-        MatroskaIndexPos *pos = pos_list->elem;
-        for (j=0; j<pos_list->nb_elem; j++) {
-            MatroskaTrack *track = matroska_find_track_by_num(matroska,
-                                                              pos[j].track);
-            if (track && track->stream)
-                av_add_index_entry(track->stream,
-                                   pos[j].pos + matroska->segment_start,
-                                   index[i].time/index_scale, 0, 0,
-                                   AVINDEX_KEYFRAME);
-        }
-    }
-
     matroska_convert_tags(s);
 
     return 0;
@@ -1624,11 +1675,13 @@ static int matroska_deliver_packet(MatroskaDemuxContext *matroska,
         memcpy(pkt, matroska->packets[0], sizeof(AVPacket));
         av_free(matroska->packets[0]);
         if (matroska->num_packets > 1) {
+            void *newpackets;
             memmove(&matroska->packets[0], &matroska->packets[1],
                     (matroska->num_packets - 1) * sizeof(AVPacket *));
-            matroska->packets =
-                av_realloc(matroska->packets, (matroska->num_packets - 1) *
-                           sizeof(AVPacket *));
+            newpackets = av_realloc(matroska->packets,
+                            (matroska->num_packets - 1) * sizeof(AVPacket *));
+            if (newpackets)
+                matroska->packets = newpackets;
         } else {
             av_freep(&matroska->packets);
         }
@@ -1954,6 +2007,12 @@ static int matroska_read_seek(AVFormatContext *s, int stream_index,
     AVStream *st = s->streams[stream_index];
     int i, index, index_sub, index_min;
 
+    /* Parse the CUES now since we need the index data to seek. */
+    if (matroska->cues_parsing_deferred) {
+        matroska_parse_cues(matroska);
+        matroska->cues_parsing_deferred = 0;
+    }
+
     if (!st->nb_index_entries)
         return 0;
     timestamp = FFMAX(timestamp, st->index_entries[0].timestamp);
@@ -2014,12 +2073,12 @@ static int matroska_read_close(AVFormatContext *s)
 }
 
 AVInputFormat ff_matroska_demuxer = {
-    "matroska,webm",
-    NULL_IF_CONFIG_SMALL("Matroska/WebM file format"),
-    sizeof(MatroskaDemuxContext),
-    matroska_probe,
-    matroska_read_header,
-    matroska_read_packet,
-    matroska_read_close,
-    matroska_read_seek,
+    .name           = "matroska,webm",
+    .long_name      = NULL_IF_CONFIG_SMALL("Matroska/WebM file format"),
+    .priv_data_size = sizeof(MatroskaDemuxContext),
+    .read_probe     = matroska_probe,
+    .read_header    = matroska_read_header,
+    .read_packet    = matroska_read_packet,
+    .read_close     = matroska_read_close,
+    .read_seek      = matroska_read_seek,
 };