From 76e062322c3527b76b9b180ff0caa52b7af4784b Mon Sep 17 00:00:00 2001 From: Marton Balint Date: Sat, 11 Dec 2021 16:27:28 +0100 Subject: [PATCH] avformat/movenc: factorize data shifting And move data shift function from movenc to utils. Signed-off-by: Marton Balint --- libavformat/internal.h | 7 ++++++ libavformat/movenc.c | 55 ++--------------------------------------- libavformat/utils.c | 56 ++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 65 insertions(+), 53 deletions(-) diff --git a/libavformat/internal.h b/libavformat/internal.h index 2ba795d669..63235ce5cf 100644 --- a/libavformat/internal.h +++ b/libavformat/internal.h @@ -1019,4 +1019,11 @@ void ff_format_set_url(AVFormatContext *s, char *url); void avpriv_register_devices(const AVOutputFormat * const o[], const AVInputFormat * const i[]); +/** + * Make shift_size amount of space at read_start by shifting data in the output + * at read_start until the current IO position. The underlying IO context must + * be seekable. + */ +int ff_format_shift_data(AVFormatContext *s, int64_t read_start, int shift_size); + #endif /* AVFORMAT_INTERNAL_H */ diff --git a/libavformat/movenc.c b/libavformat/movenc.c index 0f912dd012..40ad4f8642 100644 --- a/libavformat/movenc.c +++ b/libavformat/movenc.c @@ -7150,13 +7150,8 @@ static int compute_sidx_size(AVFormatContext *s) static int shift_data(AVFormatContext *s) { - int ret = 0, moov_size; + int moov_size; MOVMuxContext *mov = s->priv_data; - int64_t pos, pos_end; - uint8_t *buf, *read_buf[2]; - int read_buf_id = 0; - int read_size[2]; - AVIOContext *read_pb; if (mov->flags & FF_MOV_FLAG_FRAGMENT) moov_size = compute_sidx_size(s); @@ -7165,53 +7160,7 @@ static int shift_data(AVFormatContext *s) if (moov_size < 0) return moov_size; - buf = av_malloc(moov_size * 2); - if (!buf) - return AVERROR(ENOMEM); - read_buf[0] = buf; - read_buf[1] = buf + moov_size; - - /* Shift the data: the AVIO context of the output can only be used for - * writing, so we re-open the same output, but for reading. It also avoids - * a read/seek/write/seek back and forth. */ - avio_flush(s->pb); - ret = s->io_open(s, &read_pb, s->url, AVIO_FLAG_READ, NULL); - if (ret < 0) { - av_log(s, AV_LOG_ERROR, "Unable to re-open %s output file for " - "the second pass (faststart)\n", s->url); - goto end; - } - - /* mark the end of the shift to up to the last data we wrote, and get ready - * for writing */ - pos_end = avio_tell(s->pb); - avio_seek(s->pb, mov->reserved_header_pos + moov_size, SEEK_SET); - - /* start reading at where the new moov will be placed */ - avio_seek(read_pb, mov->reserved_header_pos, SEEK_SET); - pos = avio_tell(read_pb); - -#define READ_BLOCK do { \ - read_size[read_buf_id] = avio_read(read_pb, read_buf[read_buf_id], moov_size); \ - read_buf_id ^= 1; \ -} while (0) - - /* shift data by chunk of at most moov_size */ - READ_BLOCK; - do { - int n; - READ_BLOCK; - n = read_size[read_buf_id]; - if (n <= 0) - break; - avio_write(s->pb, read_buf[read_buf_id], n); - pos += n; - } while (pos < pos_end); - ff_format_io_close(s, &read_pb); - -end: - av_free(buf); - return ret; + return ff_format_shift_data(s, mov->reserved_header_pos, moov_size); } static int mov_write_trailer(AVFormatContext *s) diff --git a/libavformat/utils.c b/libavformat/utils.c index 332ba534d2..a78797ef57 100644 --- a/libavformat/utils.c +++ b/libavformat/utils.c @@ -2035,3 +2035,59 @@ const char *av_disposition_to_string(int disposition) return NULL; } + +int ff_format_shift_data(AVFormatContext *s, int64_t read_start, int shift_size) +{ + int ret; + int64_t pos, pos_end; + uint8_t *buf, *read_buf[2]; + int read_buf_id = 0; + int read_size[2]; + AVIOContext *read_pb; + + buf = av_malloc_array(shift_size, 2); + if (!buf) + return AVERROR(ENOMEM); + read_buf[0] = buf; + read_buf[1] = buf + shift_size; + + /* Shift the data: the AVIO context of the output can only be used for + * writing, so we re-open the same output, but for reading. It also avoids + * a read/seek/write/seek back and forth. */ + avio_flush(s->pb); + ret = s->io_open(s, &read_pb, s->url, AVIO_FLAG_READ, NULL); + if (ret < 0) { + av_log(s, AV_LOG_ERROR, "Unable to re-open %s output file for shifting data\n", s->url); + goto end; + } + + /* mark the end of the shift to up to the last data we wrote, and get ready + * for writing */ + pos_end = avio_tell(s->pb); + avio_seek(s->pb, read_start + shift_size, SEEK_SET); + + avio_seek(read_pb, read_start, SEEK_SET); + pos = avio_tell(read_pb); + +#define READ_BLOCK do { \ + read_size[read_buf_id] = avio_read(read_pb, read_buf[read_buf_id], shift_size); \ + read_buf_id ^= 1; \ +} while (0) + + /* shift data by chunk of at most shift_size */ + READ_BLOCK; + do { + int n; + READ_BLOCK; + n = read_size[read_buf_id]; + if (n <= 0) + break; + avio_write(s->pb, read_buf[read_buf_id], n); + pos += n; + } while (pos < pos_end); + ff_format_io_close(s, &read_pb); + +end: + av_free(buf); + return ret; +}