From 3d1506c630eb59b428eb3585ccaa446fec7f3b0a Mon Sep 17 00:00:00 2001 From: tomajsjiang Date: Thu, 4 Jul 2019 11:58:41 +0800 Subject: lavf/avio: add a ffio_realloc_buf API for AVIO buffer realloc Add new API ffio_realloc_buf for AVIO buffer realloc. Signed-off-by: Zhongxing Jiang --- libavformat/avio_internal.h | 9 +++++++++ libavformat/aviobuf.c | 31 +++++++++++++++++++++++++++++++ 2 files changed, 40 insertions(+) (limited to 'libavformat') diff --git a/libavformat/avio_internal.h b/libavformat/avio_internal.h index 04c1ad5157..eb628ac493 100644 --- a/libavformat/avio_internal.h +++ b/libavformat/avio_internal.h @@ -86,6 +86,15 @@ int ffio_read_size(AVIOContext *s, unsigned char *buf, int size); /** @warning must be called before any I/O */ int ffio_set_buf_size(AVIOContext *s, int buf_size); +/** + * Reallocate a given buffer for AVIOContext. + * + * @param s the AVIOContext to realloc. + * @param buf_size required new buffer size. + * @return 0 on success, a negative AVERROR on failure. + */ +int ffio_realloc_buf(AVIOContext *s, int buf_size); + /** * Ensures that the requested seekback buffer size will be available * diff --git a/libavformat/aviobuf.c b/libavformat/aviobuf.c index c76df714ad..a69c30e0af 100644 --- a/libavformat/aviobuf.c +++ b/libavformat/aviobuf.c @@ -1096,6 +1096,37 @@ int ffio_set_buf_size(AVIOContext *s, int buf_size) return 0; } +int ffio_realloc_buf(AVIOContext *s, int buf_size) +{ + uint8_t *buffer; + int data_size; + + if (!s->buffer_size) + return ffio_set_buf_size(s, buf_size); + + if (buf_size <= s->buffer_size) + return 0; + + buffer = av_malloc(buf_size); + if (!buffer) + return AVERROR(ENOMEM); + + data_size = s->write_flag ? (s->buf_ptr - s->buffer) : (s->buf_end - s->buf_ptr); + if (data_size > 0) + memcpy(buffer, s->write_flag ? s->buffer : s->buf_ptr, data_size); + av_free(s->buffer); + s->buffer = buffer; + s->orig_buffer_size = buf_size; + s->buffer_size = buf_size; + s->buf_ptr = s->write_flag ? (s->buffer + data_size) : s->buffer; + if (s->write_flag) + s->buf_ptr_max = s->buffer + data_size; + + s->buf_end = s->write_flag ? (s->buffer + s->buffer_size) : (s->buf_ptr + data_size); + + return 0; +} + static int url_resetbuf(AVIOContext *s, int flags) { av_assert1(flags == AVIO_FLAG_WRITE || flags == AVIO_FLAG_READ); -- cgit v1.2.3