From 5748faf291fec297ef25d81962b52b3438f54278 Mon Sep 17 00:00:00 2001 From: Justin Ruggles Date: Sun, 29 Sep 2013 19:45:57 -0400 Subject: bytestream: add bytestream2_copy_buffer() functions This is basically an overread/overwrite-safe memcpy between a GetByteContext and a PutByteContext. CC:libav-stable@libav.org --- libavcodec/bytestream.h | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) diff --git a/libavcodec/bytestream.h b/libavcodec/bytestream.h index 63d61f1132..3eab225f9c 100644 --- a/libavcodec/bytestream.h +++ b/libavcodec/bytestream.h @@ -325,6 +325,32 @@ static av_always_inline unsigned int bytestream2_get_eof(PutByteContext *p) return p->eof; } +static av_always_inline unsigned int bytestream2_copy_bufferu(PutByteContext *p, + GetByteContext *g, + unsigned int size) +{ + memcpy(p->buffer, g->buffer, size); + p->buffer += size; + g->buffer += size; + return size; +} + +static av_always_inline unsigned int bytestream2_copy_buffer(PutByteContext *p, + GetByteContext *g, + unsigned int size) +{ + int size2; + + if (p->eof) + return 0; + size = FFMIN(g->buffer_end - g->buffer, size); + size2 = FFMIN(p->buffer_end - p->buffer, size); + if (size2 != size) + p->eof = 1; + + return bytestream2_copy_bufferu(p, g, size2); +} + static av_always_inline unsigned int bytestream_get_buffer(const uint8_t **b, uint8_t *dst, unsigned int size) -- cgit v1.2.1