From 4bf90e095b361cb11371921bf6eb357831d857b2 Mon Sep 17 00:00:00 2001
From: Marton Balint <cus@passwd.hu>
Date: Sat, 4 Jan 2020 19:03:24 +0100
Subject: [PATCH] avformat: remove avio_flush() calls from the end of
 write_header functions

To make it consistent with other muxers.

The user can still control the generic flushing behaviour after write_header
(same way as after packets) using the -flush_packets option, the default
typically means to flush unless a non-streamed file output is used.

Therefore this change should have no adverse effect on streaming, even if it is
assumed that the first packet has a clean buffer, so small seekbacks within the
output buffer work even when the IO context is not seekable.

Signed-off-by: Marton Balint <cus@passwd.hu>
---
 libavformat/aiffenc.c     | 3 ---
 libavformat/amr.c         | 1 -
 libavformat/asfenc.c      | 2 --
 libavformat/assenc.c      | 1 -
 libavformat/astenc.c      | 2 --
 libavformat/au.c          | 1 -
 libavformat/avienc.c      | 2 --
 libavformat/cafenc.c      | 1 -
 libavformat/ffmetaenc.c   | 1 -
 libavformat/framehash.c   | 1 -
 libavformat/gxfenc.c      | 1 -
 libavformat/icoenc.c      | 2 --
 libavformat/idroqenc.c    | 1 -
 libavformat/ilbc.c        | 1 -
 libavformat/jacosubenc.c  | 1 -
 libavformat/matroskaenc.c | 2 --
 libavformat/microdvdenc.c | 1 -
 libavformat/mmf.c         | 2 --
 libavformat/movenc.c      | 1 -
 libavformat/mpjpeg.c      | 1 -
 libavformat/nutenc.c      | 2 --
 libavformat/rmenc.c       | 1 -
 libavformat/rsoenc.c      | 2 --
 libavformat/smjpegenc.c   | 1 -
 libavformat/soxenc.c      | 2 --
 libavformat/swfenc.c      | 1 -
 libavformat/wavenc.c      | 2 --
 libavformat/webvttenc.c   | 1 -
 28 files changed, 40 deletions(-)

diff --git a/libavformat/aiffenc.c b/libavformat/aiffenc.c
index e25794d1855..ec2c7db09ab 100644
--- a/libavformat/aiffenc.c
+++ b/libavformat/aiffenc.c
@@ -199,9 +199,6 @@ static int aiff_write_header(AVFormatContext *s)
     avpriv_set_pts_info(s->streams[aiff->audio_stream_idx], 64, 1,
                         s->streams[aiff->audio_stream_idx]->codecpar->sample_rate);
 
-    /* Data is starting here */
-    avio_flush(pb);
-
     return 0;
 }
 
diff --git a/libavformat/amr.c b/libavformat/amr.c
index 42840a50a30..650b565b1b9 100644
--- a/libavformat/amr.c
+++ b/libavformat/amr.c
@@ -60,7 +60,6 @@ static int amr_write_header(AVFormatContext *s)
     } else {
         return -1;
     }
-    avio_flush(pb);
     return 0;
 }
 
diff --git a/libavformat/asfenc.c b/libavformat/asfenc.c
index 44e11fc7635..d03cff91c0b 100644
--- a/libavformat/asfenc.c
+++ b/libavformat/asfenc.c
@@ -801,8 +801,6 @@ static int asf_write_header(AVFormatContext *s)
         return -1;
     }
 
-    avio_flush(s->pb);
-
     asf->packet_nb_payloads     = 0;
     asf->packet_timestamp_start = -1;
     asf->packet_timestamp_end   = -1;
diff --git a/libavformat/assenc.c b/libavformat/assenc.c
index 12aadca1712..68c3396e5ad 100644
--- a/libavformat/assenc.c
+++ b/libavformat/assenc.c
@@ -77,7 +77,6 @@ static int write_header(AVFormatContext *s)
             avio_printf(s->pb, "[Events]\r\nFormat: %s, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text\r\n",
                         ass->ssa_mode ? "Marked" : "Layer");
     }
-    avio_flush(s->pb);
 
     return 0;
 }
diff --git a/libavformat/astenc.c b/libavformat/astenc.c
index 578e658891e..d38a3aab38b 100644
--- a/libavformat/astenc.c
+++ b/libavformat/astenc.c
@@ -101,8 +101,6 @@ static int ast_write_header(AVFormatContext *s)
     avio_wb64(pb, 0);
     avio_wb32(pb, 0);
 
-    avio_flush(pb);
-
     return 0;
 }
 
diff --git a/libavformat/au.c b/libavformat/au.c
index cb48e67feb4..19a0f569636 100644
--- a/libavformat/au.c
+++ b/libavformat/au.c
@@ -311,7 +311,6 @@ static int au_write_header(AVFormatContext *s)
     } else {
         avio_wb64(pb, 0); /* annotation field */
     }
-    avio_flush(pb);
 
     return 0;
 }
diff --git a/libavformat/avienc.c b/libavformat/avienc.c
index 940ea335102..23cc58ea76c 100644
--- a/libavformat/avienc.c
+++ b/libavformat/avienc.c
@@ -580,8 +580,6 @@ static int avi_write_header(AVFormatContext *s)
     avi->movi_list = ff_start_tag(pb, "LIST");
     ffio_wfourcc(pb, "movi");
 
-    avio_flush(pb);
-
     return 0;
 }
 
diff --git a/libavformat/cafenc.c b/libavformat/cafenc.c
index 0f7c4ebbb32..8fe1dcef19c 100644
--- a/libavformat/cafenc.c
+++ b/libavformat/cafenc.c
@@ -203,7 +203,6 @@ static int caf_write_header(AVFormatContext *s)
     avio_wb64(pb, -1);        //< mChunkSize
     avio_wb32(pb, 0);         //< mEditCount
 
-    avio_flush(pb);
     return 0;
 }
 
diff --git a/libavformat/ffmetaenc.c b/libavformat/ffmetaenc.c
index a9adbb1d19c..800fb1887c6 100644
--- a/libavformat/ffmetaenc.c
+++ b/libavformat/ffmetaenc.c
@@ -54,7 +54,6 @@ static int write_header(AVFormatContext *s)
     avio_write(s->pb, ID_STRING, sizeof(ID_STRING) - 1);
     avio_w8(s->pb, '1');          // version
     avio_w8(s->pb, '\n');
-    avio_flush(s->pb);
     return 0;
 }
 
diff --git a/libavformat/framehash.c b/libavformat/framehash.c
index 3ae9092c61d..8d90793d7c7 100644
--- a/libavformat/framehash.c
+++ b/libavformat/framehash.c
@@ -45,7 +45,6 @@ int ff_framehash_write_header(AVFormatContext *s)
             avio_printf(s->pb, "#sar %d: %d/%d\n", i, st->sample_aspect_ratio.num, st->sample_aspect_ratio.den);
             break;
         }
-        avio_flush(s->pb);
     }
     return 0;
 }
diff --git a/libavformat/gxfenc.c b/libavformat/gxfenc.c
index ad9ddea8877..c9fb0dcd91b 100644
--- a/libavformat/gxfenc.c
+++ b/libavformat/gxfenc.c
@@ -834,7 +834,6 @@ static int gxf_write_header(AVFormatContext *s)
 
     gxf->packet_count = 3;
 
-    avio_flush(pb);
     return 0;
 }
 
diff --git a/libavformat/icoenc.c b/libavformat/icoenc.c
index 975c3466bf2..a7df8b72bc6 100644
--- a/libavformat/icoenc.c
+++ b/libavformat/icoenc.c
@@ -106,8 +106,6 @@ static int ico_write_header(AVFormatContext *s)
     if (!ico->images)
         return AVERROR(ENOMEM);
 
-    avio_flush(pb);
-
     return 0;
 }
 
diff --git a/libavformat/idroqenc.c b/libavformat/idroqenc.c
index 8122efef835..261f21939cc 100644
--- a/libavformat/idroqenc.c
+++ b/libavformat/idroqenc.c
@@ -55,7 +55,6 @@ static int roq_write_header(struct AVFormatContext *s)
     }
 
     avio_write(s->pb, header, 8);
-    avio_flush(s->pb);
 
     return 0;
 }
diff --git a/libavformat/ilbc.c b/libavformat/ilbc.c
index ba11953b59c..01c7112ad17 100644
--- a/libavformat/ilbc.c
+++ b/libavformat/ilbc.c
@@ -49,7 +49,6 @@ static int ilbc_write_header(AVFormatContext *s)
         av_log(s, AV_LOG_ERROR, "Unsupported mode\n");
         return AVERROR(EINVAL);
     }
-    avio_flush(pb);
     return 0;
 }
 
diff --git a/libavformat/jacosubenc.c b/libavformat/jacosubenc.c
index 0954f5f0585..77575c6b3c0 100644
--- a/libavformat/jacosubenc.c
+++ b/libavformat/jacosubenc.c
@@ -25,7 +25,6 @@ static int jacosub_write_header(AVFormatContext *s)
 
     if (par->extradata_size) {
         avio_write(s->pb, par->extradata, par->extradata_size - 1);
-        avio_flush(s->pb);
     }
     return 0;
 }
diff --git a/libavformat/matroskaenc.c b/libavformat/matroskaenc.c
index 9dcd1946e88..4b6d14b435f 100644
--- a/libavformat/matroskaenc.c
+++ b/libavformat/matroskaenc.c
@@ -2000,8 +2000,6 @@ static int mkv_write_header(AVFormatContext *s)
     mkv->cur_audio_pkt.size = 0;
     mkv->cluster_pos = -1;
 
-    avio_flush(pb);
-
     // start a new cluster every 5 MB or 5 sec, or 32k / 1 sec for streaming or
     // after 4k and on a keyframe
     if (pb->seekable & AVIO_SEEKABLE_NORMAL) {
diff --git a/libavformat/microdvdenc.c b/libavformat/microdvdenc.c
index 80e6fa8674e..1cd215d8def 100644
--- a/libavformat/microdvdenc.c
+++ b/libavformat/microdvdenc.c
@@ -37,7 +37,6 @@ static int microdvd_write_header(struct AVFormatContext *s)
         avio_write(s->pb, "{DEFAULT}{}", 11);
         avio_write(s->pb, par->extradata, par->extradata_size);
         avio_w8(s->pb, '\n');
-        avio_flush(s->pb);
     }
 
     avpriv_set_pts_info(s->streams[0], 64, framerate.num, framerate.den);
diff --git a/libavformat/mmf.c b/libavformat/mmf.c
index 917113066aa..4e087fc9203 100644
--- a/libavformat/mmf.c
+++ b/libavformat/mmf.c
@@ -123,8 +123,6 @@ static int mmf_write_header(AVFormatContext *s)
 
     avpriv_set_pts_info(s->streams[0], 64, 1, s->streams[0]->codecpar->sample_rate);
 
-    avio_flush(pb);
-
     return 0;
 }
 
diff --git a/libavformat/movenc.c b/libavformat/movenc.c
index e422bdd071a..e20eea75714 100644
--- a/libavformat/movenc.c
+++ b/libavformat/movenc.c
@@ -6579,7 +6579,6 @@ static int mov_write_header(AVFormatContext *s)
         !(mov->flags & FF_MOV_FLAG_DELAY_MOOV)) {
         if ((ret = mov_write_moov_tag(pb, mov, s)) < 0)
             return ret;
-        avio_flush(pb);
         mov->moov_written = 1;
         if (mov->flags & FF_MOV_FLAG_GLOBAL_SIDX)
             mov->reserved_header_pos = avio_tell(pb);
diff --git a/libavformat/mpjpeg.c b/libavformat/mpjpeg.c
index 80f83c58719..e410e848017 100644
--- a/libavformat/mpjpeg.c
+++ b/libavformat/mpjpeg.c
@@ -34,7 +34,6 @@ static int mpjpeg_write_header(AVFormatContext *s)
 {
     MPJPEGContext *mpj = s->priv_data;
     avio_printf(s->pb, "--%s\r\n", mpj->boundary_tag);
-    avio_flush(s->pb);
     return 0;
 }
 
diff --git a/libavformat/nutenc.c b/libavformat/nutenc.c
index 46dce7722dd..44773924dd7 100644
--- a/libavformat/nutenc.c
+++ b/libavformat/nutenc.c
@@ -768,8 +768,6 @@ static int nut_write_header(AVFormatContext *s)
     if (s->avoid_negative_ts < 0)
         s->avoid_negative_ts = 1;
 
-    avio_flush(bc);
-
     return 0;
 }
 
diff --git a/libavformat/rmenc.c b/libavformat/rmenc.c
index 3bff4daf0a7..e137dbc44fe 100644
--- a/libavformat/rmenc.c
+++ b/libavformat/rmenc.c
@@ -360,7 +360,6 @@ static int rm_write_header(AVFormatContext *s)
 
     if (rv10_write_header(s, 0, 0))
         return AVERROR_INVALIDDATA;
-    avio_flush(s->pb);
     return 0;
 }
 
diff --git a/libavformat/rsoenc.c b/libavformat/rsoenc.c
index e34e2c64e20..3159f0c4277 100644
--- a/libavformat/rsoenc.c
+++ b/libavformat/rsoenc.c
@@ -60,8 +60,6 @@ static int rso_write_header(AVFormatContext *s)
     avio_wb16(pb, par->sample_rate);
     avio_wb16(pb, 0x0000);           /* play mode ? (0x0000 = don't loop) */
 
-    avio_flush(pb);
-
     return 0;
 }
 
diff --git a/libavformat/smjpegenc.c b/libavformat/smjpegenc.c
index 68a128647e3..c3c1a6346c5 100644
--- a/libavformat/smjpegenc.c
+++ b/libavformat/smjpegenc.c
@@ -88,7 +88,6 @@ static int smjpeg_write_header(AVFormatContext *s)
     }
 
     avio_wl32(pb, SMJPEG_HEND);
-    avio_flush(pb);
 
     return 0;
 }
diff --git a/libavformat/soxenc.c b/libavformat/soxenc.c
index 7b37bd48484..7259131b036 100644
--- a/libavformat/soxenc.c
+++ b/libavformat/soxenc.c
@@ -80,8 +80,6 @@ static int sox_write_header(AVFormatContext *s)
 
     ffio_fill(pb, 0, comment_size - comment_len);
 
-    avio_flush(pb);
-
     return 0;
 }
 
diff --git a/libavformat/swfenc.c b/libavformat/swfenc.c
index f53db0fb2b3..84f924eda52 100644
--- a/libavformat/swfenc.c
+++ b/libavformat/swfenc.c
@@ -337,7 +337,6 @@ static int swf_write_header(AVFormatContext *s)
         put_swf_end_tag(s);
     }
 
-    avio_flush(s->pb);
     return 0;
 }
 
diff --git a/libavformat/wavenc.c b/libavformat/wavenc.c
index 2b281490565..c44d6d26e9d 100644
--- a/libavformat/wavenc.c
+++ b/libavformat/wavenc.c
@@ -361,8 +361,6 @@ static int wav_write_header(AVFormatContext *s)
         wav->data = ff_start_tag(pb, "data");
     }
 
-    avio_flush(pb);
-
     return 0;
 }
 
diff --git a/libavformat/webvttenc.c b/libavformat/webvttenc.c
index 61b7f546229..cbd989dcb6c 100644
--- a/libavformat/webvttenc.c
+++ b/libavformat/webvttenc.c
@@ -57,7 +57,6 @@ static int webvtt_write_header(AVFormatContext *ctx)
     avpriv_set_pts_info(s, 64, 1, 1000);
 
     avio_printf(pb, "WEBVTT\n");
-    avio_flush(pb);
 
     return 0;
 }
-- 
2.39.2