From 84d88154995e26ff2dea6b17893a70d309983918 Mon Sep 17 00:00:00 2001 From: Marton Balint Date: Tue, 29 Sep 2020 00:15:27 +0200 Subject: [PATCH] avformat/aviobuf: do not allocate a new buffer in ffio_ensure_seekback if not needed Let's move unread data to the start of the old buffer instead. Signed-off-by: Marton Balint --- libavformat/aviobuf.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/libavformat/aviobuf.c b/libavformat/aviobuf.c index 75ddf52efcf..2f1abe7d815 100644 --- a/libavformat/aviobuf.c +++ b/libavformat/aviobuf.c @@ -1015,7 +1015,10 @@ int ffio_ensure_seekback(AVIOContext *s, int64_t buf_size) return 0; av_assert0(!s->write_flag); - buf_size = FFMAX(buf_size, s->buffer_size); + if (buf_size <= s->buffer_size) { + update_checksum(s); + memmove(s->buffer, s->buf_ptr, filled); + } else { buffer = av_malloc(buf_size); if (!buffer) return AVERROR(ENOMEM); @@ -1024,6 +1027,7 @@ int ffio_ensure_seekback(AVIOContext *s, int64_t buf_size) av_free(s->buffer); s->buffer = buffer; s->buffer_size = buf_size; + } s->buf_ptr = s->buffer; s->buf_end = s->buffer + filled; s->checksum_ptr = s->buffer; -- 2.39.2