flacparse: don't map buffer multiple times when parsing

This commit is contained in:
Tim-Philipp Müller 2016-01-05 18:13:06 +00:00
parent 910d75ddaf
commit 6dab3ece07

View file

@ -646,29 +646,23 @@ need_more_data:
static gboolean
gst_flac_parse_frame_is_valid (GstFlacParse * flacparse,
GstBaseParseFrame * frame, guint * ret)
const guint8 * data, gsize size, guint * ret)
{
GstBuffer *buffer;
GstMapInfo map;
guint max, remaining;
guint i, search_start, search_end;
FrameHeaderCheckReturn header_ret;
guint16 block_size;
gboolean suspect_start = FALSE, suspect_end = FALSE;
gboolean result = FALSE;
buffer = frame->buffer;
gst_buffer_map (buffer, &map, GST_MAP_READ);
if (map.size < flacparse->min_framesize)
if (size < flacparse->min_framesize)
goto need_more;
header_ret =
gst_flac_parse_frame_header_is_valid (flacparse, map.data, map.size, TRUE,
gst_flac_parse_frame_header_is_valid (flacparse, data, size, TRUE,
&block_size, &suspect_start);
if (header_ret == FRAME_HEADER_INVALID) {
*ret = 0;
goto cleanup;
return FALSE;
}
if (header_ret == FRAME_HEADER_MORE_DATA)
goto need_more;
@ -676,27 +670,27 @@ gst_flac_parse_frame_is_valid (GstFlacParse * flacparse,
/* mind unknown framesize */
search_start = MAX (2, flacparse->min_framesize);
if (flacparse->max_framesize)
search_end = MIN (map.size, flacparse->max_framesize + 9 + 2);
search_end = MIN (size, flacparse->max_framesize + 9 + 2);
else
search_end = map.size;
search_end = size;
search_end -= 2;
remaining = map.size;
remaining = size;
for (i = search_start; i < search_end; i++, remaining--) {
if ((GST_READ_UINT16_BE (map.data + i) & 0xfffe) != 0xfff8)
if ((GST_READ_UINT16_BE (data + i) & 0xfffe) != 0xfff8)
continue;
GST_LOG_OBJECT (flacparse, "possible frame end at offset %d", i);
suspect_end = FALSE;
header_ret =
gst_flac_parse_frame_header_is_valid (flacparse, map.data + i,
gst_flac_parse_frame_header_is_valid (flacparse, data + i,
remaining, FALSE, NULL, &suspect_end);
if (header_ret == FRAME_HEADER_VALID) {
if (flacparse->check_frame_checksums || suspect_start || suspect_end) {
guint16 actual_crc = gst_flac_calculate_crc16 (map.data, i - 2);
guint16 expected_crc = GST_READ_UINT16_BE (map.data + i - 2);
guint16 actual_crc = gst_flac_calculate_crc16 (data, i - 2);
guint16 expected_crc = GST_READ_UINT16_BE (data + i - 2);
GST_LOG_OBJECT (flacparse,
"Found possible frame (%d, %d). Checking for CRC match",
@ -710,8 +704,7 @@ gst_flac_parse_frame_is_valid (GstFlacParse * flacparse,
}
*ret = i;
flacparse->block_size = block_size;
result = TRUE;
goto cleanup;
return TRUE;
} else if (header_ret == FRAME_HEADER_MORE_DATA) {
goto need_more;
}
@ -720,20 +713,18 @@ gst_flac_parse_frame_is_valid (GstFlacParse * flacparse,
/* For the last frame output everything to the end */
if (G_UNLIKELY (GST_BASE_PARSE_DRAINING (flacparse))) {
if (flacparse->check_frame_checksums) {
guint16 actual_crc = gst_flac_calculate_crc16 (map.data, map.size - 2);
guint16 expected_crc = GST_READ_UINT16_BE (map.data + map.size - 2);
guint16 actual_crc = gst_flac_calculate_crc16 (data, size - 2);
guint16 expected_crc = GST_READ_UINT16_BE (data + size - 2);
if (actual_crc == expected_crc) {
*ret = map.size;
*ret = size;
flacparse->block_size = block_size;
result = TRUE;
goto cleanup;
return TRUE;
}
} else {
*ret = map.size;
*ret = size;
flacparse->block_size = block_size;
result = TRUE;
goto cleanup;
return TRUE;
}
}
@ -750,12 +741,8 @@ need_more:
max = flacparse->max_framesize + 16;
if (max == 16)
max = 1 << 24;
*ret = MIN (map.size + 4096, max);
result = TRUE;
cleanup:
gst_buffer_unmap (buffer, &map);
return result;
*ret = MIN (size + 4096, max);
return TRUE;
}
static GstFlowReturn
@ -815,7 +802,7 @@ gst_flac_parse_handle_frame (GstBaseParse * parse,
flacparse->sample_number = 0;
GST_DEBUG_OBJECT (flacparse, "Found sync code");
ret = gst_flac_parse_frame_is_valid (flacparse, frame, &next);
ret = gst_flac_parse_frame_is_valid (flacparse, map.data, map.size, &next);
if (ret) {
framesize = next;
goto cleanup;