avformat/ffmetadec: do no limit size of tags to 1024

Use bprint API instead.

Fixes #4833.
This commit is contained in:
Paul B Mahol 2018-12-13 13:06:30 +01:00
parent c6e1966c1a
commit 78e7b70395

View File

@ -19,6 +19,7 @@
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "libavutil/bprint.h"
#include "libavutil/mathematics.h"
#include "avformat.h"
#include "ffmeta.h"
@ -32,6 +33,48 @@ static int probe(AVProbeData *p)
return 0;
}
static int64_t read_line_to_bprint_escaped(AVIOContext *s, AVBPrint *bp)
{
int len, end;
int64_t read = 0;
char tmp[1024];
char c;
char prev = ' ';
do {
len = 0;
do {
c = avio_r8(s);
end = prev != '\\' && (c == '\r' || c == '\n' || c == '\0');
if (!end)
tmp[len++] = c;
prev = c;
} while (!end && len < sizeof(tmp));
av_bprint_append_data(bp, tmp, len);
read += len;
} while (!end);
if (c == '\r' && avio_r8(s) != '\n' && !avio_feof(s))
avio_skip(s, -1);
if (!c && s->error)
return s->error;
if (!c && !read && avio_feof(s))
return AVERROR_EOF;
return read;
}
static void get_bprint_line(AVIOContext *s, AVBPrint *bp)
{
do {
av_bprint_clear(bp);
read_line_to_bprint_escaped(s, bp);
} while (!avio_feof(s) && (bp->str[0] == ';' || bp->str[0] == '#' || bp->str[0] == 0));
}
static void get_line(AVIOContext *s, uint8_t *buf, int size)
{
do {
@ -128,12 +171,14 @@ static int read_tag(const uint8_t *line, AVDictionary **m)
static int read_header(AVFormatContext *s)
{
AVDictionary **m = &s->metadata;
uint8_t line[1024];
AVBPrint bp;
av_bprint_init(&bp, 0, AV_BPRINT_SIZE_UNLIMITED);
while(!avio_feof(s->pb)) {
get_line(s->pb, line, sizeof(line));
get_bprint_line(s->pb, &bp);
if (!memcmp(line, ID_STREAM, strlen(ID_STREAM))) {
if (!memcmp(bp.str, ID_STREAM, strlen(ID_STREAM))) {
AVStream *st = avformat_new_stream(s, NULL);
if (!st)
@ -143,7 +188,7 @@ static int read_header(AVFormatContext *s)
st->codecpar->codec_id = AV_CODEC_ID_FFMETADATA;
m = &st->metadata;
} else if (!memcmp(line, ID_CHAPTER, strlen(ID_CHAPTER))) {
} else if (!memcmp(bp.str, ID_CHAPTER, strlen(ID_CHAPTER))) {
AVChapter *ch = read_chapter(s);
if (!ch)
@ -151,9 +196,11 @@ static int read_header(AVFormatContext *s)
m = &ch->metadata;
} else
read_tag(line, m);
read_tag(bp.str, m);
}
av_bprint_finalize(&bp, NULL);
s->start_time = 0;
if (s->nb_chapters)
s->duration = av_rescale_q(s->chapters[s->nb_chapters - 1]->end,