From patchwork Tue Sep 29 21:10:14 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marton Balint X-Patchwork-Id: 22659 Return-Path: X-Original-To: patchwork@ffaux-bg.ffmpeg.org Delivered-To: patchwork@ffaux-bg.ffmpeg.org Received: from ffbox0-bg.mplayerhq.hu (ffbox0-bg.ffmpeg.org [79.124.17.100]) by ffaux.localdomain (Postfix) with ESMTP id A6408449925 for ; Wed, 30 Sep 2020 00:10:39 +0300 (EEST) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id 91E8E68B01D; Wed, 30 Sep 2020 00:10:39 +0300 (EEST) X-Original-To: ffmpeg-devel@ffmpeg.org Delivered-To: ffmpeg-devel@ffmpeg.org Received: from iq.passwd.hu (iq.passwd.hu [217.27.212.140]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id 75D2F68B4D9 for ; Wed, 30 Sep 2020 00:10:33 +0300 (EEST) Received: from localhost (localhost [127.0.0.1]) by iq.passwd.hu (Postfix) with ESMTP id D4EADE4612; Tue, 29 Sep 2020 23:10:32 +0200 (CEST) X-Virus-Scanned: amavisd-new at passwd.hu Received: from iq.passwd.hu ([127.0.0.1]) by localhost (iq.passwd.hu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 7pHLsPPAJ7Zn; Tue, 29 Sep 2020 23:10:31 +0200 (CEST) Received: from bluegene.passwd.hu (localhost [127.0.0.1]) by iq.passwd.hu (Postfix) with ESMTP id 01423E4333; Tue, 29 Sep 2020 23:10:30 +0200 (CEST) From: Marton Balint To: ffmpeg-devel@ffmpeg.org Date: Tue, 29 Sep 2020 23:10:14 +0200 Message-Id: <20200929211021.25030-2-cus@passwd.hu> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200929211021.25030-1-cus@passwd.hu> References: <20200929211021.25030-1-cus@passwd.hu> MIME-Version: 1.0 Subject: [FFmpeg-devel] [PATCH 2/9] avformat/aviobuf: check if requested seekback buffer is already read X-BeenThere: ffmpeg-devel@ffmpeg.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: FFmpeg development discussions and patches List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: FFmpeg development discussions and patches Cc: Marton Balint Errors-To: ffmpeg-devel-bounces@ffmpeg.org Sender: "ffmpeg-devel" Existing code did not check if the requested seekback buffer is already read entirely. In this case, nothing has to be done to guarantee seekback. Signed-off-by: Marton Balint --- libavformat/aviobuf.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/libavformat/aviobuf.c b/libavformat/aviobuf.c index 9675425349..d94be478ac 100644 --- a/libavformat/aviobuf.c +++ b/libavformat/aviobuf.c @@ -999,6 +999,9 @@ int ffio_ensure_seekback(AVIOContext *s, int64_t buf_size) int filled = s->buf_end - s->buffer; ptrdiff_t checksum_ptr_offset = s->checksum_ptr ? s->checksum_ptr - s->buffer : -1; + if (buf_size <= s->buf_end - s->buf_ptr) + return 0; + buf_size += s->buf_ptr - s->buffer + max_buffer_size; if (buf_size < filled || s->seekable || !s->read_packet)