From: Andre Noll <maan@tuebingen.mpg.de>
Date: Mon, 9 Aug 2021 19:39:31 +0000 (+0200)
Subject: mp4: Introduce track helper variables.
X-Git-Tag: v0.7.1~7^2~118
X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=commitdiff_plain;h=bf00c9051afa0011129cef89107ada198e8da8af

mp4: Introduce track helper variables.

This reduces the line length and thus improves the readability of the
code.
---

diff --git a/mp4.c b/mp4.c
index e66fcea2..fa6f8704 100644
--- a/mp4.c
+++ b/mp4.c
@@ -434,52 +434,47 @@ static uint32_t mp4ff_read_int32(mp4ff_t * f)
 
 static int32_t mp4ff_read_stsz(mp4ff_t * f)
 {
+	int32_t i;
+	mp4ff_track_t *t;
+
 	if (f->total_tracks == 0)
 		return f->error++;
-
+	t = f->track[f->total_tracks - 1];
 	mp4ff_read_char(f);	/* version */
 	mp4ff_read_int24(f);	/* flags */
-	f->track[f->total_tracks - 1]->stsz_sample_size = mp4ff_read_int32(f);
-	f->track[f->total_tracks - 1]->stsz_sample_count = mp4ff_read_int32(f);
-
-	if (f->track[f->total_tracks - 1]->stsz_sample_size == 0) {
-		int32_t i;
-		f->track[f->total_tracks - 1]->stsz_table =
-			para_malloc(f->track[f->total_tracks - 1]->stsz_sample_count
-				* sizeof (int32_t));
-		for (i = 0; i < f->track[f->total_tracks - 1]->stsz_sample_count
-				&& !f->stream->read_error; i++) {
-			f->track[f->total_tracks - 1]->stsz_table[i] = mp4ff_read_int32(f);
-		}
-	}
+	t->stsz_sample_size = mp4ff_read_int32(f);
+	t->stsz_sample_count = mp4ff_read_int32(f);
+	if (t->stsz_sample_size != 0)
+		return 0;
+	t->stsz_table = para_malloc(t->stsz_sample_count * sizeof(int32_t));
+	for (i = 0; i < t->stsz_sample_count && !f->stream->read_error; i++)
+		t->stsz_table[i] = mp4ff_read_int32(f);
 	return 0;
 }
 
 static int32_t mp4ff_read_stts(mp4ff_t * f)
 {
 	int32_t i;
-	mp4ff_track_t *p_track;
+	mp4ff_track_t *t;
 
 	/* CVE-2017-9223 */
 	if (f->total_tracks == 0)
 		return f->error++;
-
-	p_track = f->track[f->total_tracks - 1];
-
-	if (p_track->stts_entry_count)
+	t = f->track[f->total_tracks - 1];
+	if (t->stts_entry_count)
 		return 0;
-
 	mp4ff_read_char(f);	/* version */
 	mp4ff_read_int24(f);	/* flags */
-	p_track->stts_entry_count = mp4ff_read_int32(f);
+	t->stts_entry_count = mp4ff_read_int32(f);
 
-	p_track->stts_sample_count = para_malloc(p_track->stts_entry_count
-		 * sizeof (int32_t));
-	p_track->stts_sample_delta = para_malloc(p_track->stts_entry_count
+	t->stts_sample_count = para_malloc(t->stts_entry_count
+		* sizeof(int32_t));
+	t->stts_sample_delta = para_malloc(t->stts_entry_count
 		* sizeof (int32_t));
-	for (i = 0; i < f->track[f->total_tracks - 1]->stts_entry_count && !f->stream->read_error; i++) { /* CVE-2017-9254 */
-		p_track->stts_sample_count[i] = mp4ff_read_int32(f);
-		p_track->stts_sample_delta[i] = mp4ff_read_int32(f);
+	/* CVE-2017-9254 */
+	for (i = 0; i < t->stts_entry_count && !f->stream->read_error; i++) {
+		t->stts_sample_count[i] = mp4ff_read_int32(f);
+		t->stts_sample_delta[i] = mp4ff_read_int32(f);
 	}
 	return 1;
 }
@@ -487,27 +482,27 @@ static int32_t mp4ff_read_stts(mp4ff_t * f)
 static int32_t mp4ff_read_ctts(mp4ff_t * f)
 {
 	int32_t i;
-	mp4ff_track_t *p_track;
+	mp4ff_track_t *t;
 
 	if (f->total_tracks == 0)
 		return f->error++;
-
-	p_track = f->track[f->total_tracks - 1];
-	if (p_track->ctts_entry_count)
+	t = f->track[f->total_tracks - 1];
+	if (t->ctts_entry_count)
 		return 0;
 
 	mp4ff_read_char(f);	/* version */
 	mp4ff_read_int24(f);	/* flags */
-	p_track->ctts_entry_count = mp4ff_read_int32(f);
+	t->ctts_entry_count = mp4ff_read_int32(f);
 
-	p_track->ctts_sample_count = para_malloc(p_track->ctts_entry_count
+	t->ctts_sample_count = para_malloc(t->ctts_entry_count
 		* sizeof (int32_t));
-	p_track->ctts_sample_offset = para_malloc(p_track->ctts_entry_count
+	t->ctts_sample_offset = para_malloc(t->ctts_entry_count
 		* sizeof (int32_t));
 
-	for (i = 0; i < f->track[f->total_tracks - 1]->ctts_entry_count && !f->stream->read_error; i++) { /* CVE-2017-9257 */
-		p_track->ctts_sample_count[i] = mp4ff_read_int32(f);
-		p_track->ctts_sample_offset[i] = mp4ff_read_int32(f);
+	/* CVE-2017-9257 */
+	for (i = 0; i < t->ctts_entry_count && !f->stream->read_error; i++) {
+		t->ctts_sample_count[i] = mp4ff_read_int32(f);
+		t->ctts_sample_offset[i] = mp4ff_read_int32(f);
 	}
 	return 1;
 }
@@ -515,55 +510,47 @@ static int32_t mp4ff_read_ctts(mp4ff_t * f)
 static int32_t mp4ff_read_stsc(mp4ff_t * f)
 {
 	int32_t i;
+	mp4ff_track_t *t;
 
 	if (f->total_tracks == 0)
 		return f->error++;
+	t = f->track[f->total_tracks - 1];
 
 	mp4ff_read_char(f);	/* version */
 	mp4ff_read_int24(f);	/* flags */
-	f->track[f->total_tracks - 1]->stsc_entry_count = mp4ff_read_int32(f);
-
-	f->track[f->total_tracks - 1]->stsc_first_chunk =
-		para_malloc(f->track[f->total_tracks - 1]->stsc_entry_count *
-		sizeof (int32_t));
-	f->track[f->total_tracks - 1]->stsc_samples_per_chunk =
-		para_malloc(f->track[f->total_tracks - 1]->stsc_entry_count *
-		sizeof (int32_t));
-	f->track[f->total_tracks - 1]->stsc_sample_desc_index =
-		para_malloc(f->track[f->total_tracks - 1]->stsc_entry_count *
+	t->stsc_entry_count = mp4ff_read_int32(f);
+	t->stsc_first_chunk = para_malloc(t->stsc_entry_count * sizeof(int32_t));
+	t->stsc_samples_per_chunk = para_malloc(t->stsc_entry_count
+		* sizeof (int32_t));
+	t->stsc_sample_desc_index = para_malloc(t->stsc_entry_count *
 		sizeof (int32_t));
 
-	for (i = 0; i < f->track[f->total_tracks - 1]->stsc_entry_count && !f->stream->read_error; i++) {	/* CVE-2017-9255 */
-		f->track[f->total_tracks - 1]->stsc_first_chunk[i] =
-			mp4ff_read_int32(f);
-		f->track[f->total_tracks - 1]->stsc_samples_per_chunk[i] =
-			mp4ff_read_int32(f);
-		f->track[f->total_tracks - 1]->stsc_sample_desc_index[i] =
-			mp4ff_read_int32(f);
+	/* CVE-2017-9255 */
+	for (i = 0; i < t->stsc_entry_count && !f->stream->read_error; i++) {
+		t->stsc_first_chunk[i] = mp4ff_read_int32(f);
+		t->stsc_samples_per_chunk[i] = mp4ff_read_int32(f);
+		t->stsc_sample_desc_index[i] = mp4ff_read_int32(f);
 	}
-
 	return 0;
 }
 
 static int32_t mp4ff_read_stco(mp4ff_t * f)
 {
 	int32_t i;
+	mp4ff_track_t *t;
 
 	if (f->total_tracks == 0)
 		return f->error++;
+	t = f->track[f->total_tracks - 1];
 
 	mp4ff_read_char(f);	/* version */
 	mp4ff_read_int24(f);	/* flags */
-	f->track[f->total_tracks - 1]->stco_entry_count = mp4ff_read_int32(f);
-
-	f->track[f->total_tracks - 1]->stco_chunk_offset =
-		para_malloc(f->track[f->total_tracks - 1]->stco_entry_count *
-		sizeof (int32_t));
-	for (i = 0; i < f->track[f->total_tracks - 1]->stco_entry_count && !f->stream->read_error; i++) {	/* CVE-2017-9256 */
-		f->track[f->total_tracks - 1]->stco_chunk_offset[i] =
-		mp4ff_read_int32(f);
-	}
-
+	t->stco_entry_count = mp4ff_read_int32(f);
+	t->stco_chunk_offset = para_malloc(t->stco_entry_count
+		* sizeof(int32_t));
+	/* CVE-2017-9256 */
+	for (i = 0; i < t->stco_entry_count && !f->stream->read_error; i++)
+		t->stco_chunk_offset[i] = mp4ff_read_int32(f);
 	return 0;
 }
 
@@ -599,13 +586,13 @@ static int32_t mp4ff_read_esds(mp4ff_t * f)
 {
 	uint8_t tag;
 	uint32_t temp;
+	mp4ff_track_t *t;
 
 	if (f->total_tracks == 0)
 		return f->error++;
-
+	t = f->track[f->total_tracks - 1];
 	mp4ff_read_char(f);	/* version */
 	mp4ff_read_int24(f);	/* flags */
-
 	/* get and verify ES_DescrTag */
 	tag = mp4ff_read_char(f);
 	if (tag == 0x03) {
@@ -630,10 +617,10 @@ static int32_t mp4ff_read_esds(mp4ff_t * f)
 	if (temp < 13)
 		return 1;
 
-	f->track[f->total_tracks - 1]->audioType = mp4ff_read_char(f);
+	t->audioType = mp4ff_read_char(f);
 	mp4ff_read_int32(f);	//0x15000414 ????
-	f->track[f->total_tracks - 1]->maxBitrate = mp4ff_read_int32(f);
-	f->track[f->total_tracks - 1]->avgBitrate = mp4ff_read_int32(f);
+	t->maxBitrate = mp4ff_read_int32(f);
+	t->avgBitrate = mp4ff_read_int32(f);
 
 	/* get and verify DecSpecificInfoTag */
 	if (mp4ff_read_char(f) != 0x05) {
@@ -641,28 +628,24 @@ static int32_t mp4ff_read_esds(mp4ff_t * f)
 	}
 
 	/* read length */
-	f->track[f->total_tracks - 1]->decoderConfigLen =
-		mp4ff_read_mp4_descr_length(f);
-
-	free(f->track[f->total_tracks - 1]->decoderConfig);
-	f->track[f->total_tracks - 1]->decoderConfig =
-		para_malloc(f->track[f->total_tracks - 1]->decoderConfigLen);
-	if (f->track[f->total_tracks - 1]->decoderConfig) {
-		mp4ff_read_data(f, f->track[f->total_tracks - 1]->decoderConfig,
-				f->track[f->total_tracks -
-					 1]->decoderConfigLen);
-	}
+	t->decoderConfigLen = mp4ff_read_mp4_descr_length(f);
+	free(t->decoderConfig);
+	t->decoderConfig = para_malloc(t->decoderConfigLen);
+	mp4ff_read_data(f, t->decoderConfig, t->decoderConfigLen);
 	/* will skip the remainder of the atom */
 	return 0;
 }
+
 static int32_t mp4ff_read_mp4a(mp4ff_t * f)
 {
 	int32_t i;
 	uint8_t atom_type = 0;
 	uint8_t header_size = 0;
+	mp4ff_track_t *t;
 
 	if (f->total_tracks == 0)
 		return f->error++;
+	t = f->track[f->total_tracks - 1];
 
 	for (i = 0; i < 6; i++) {
 		mp4ff_read_char(f);	/* reserved */
@@ -672,13 +655,13 @@ static int32_t mp4ff_read_mp4a(mp4ff_t * f)
 	mp4ff_read_int32(f);	/* reserved */
 	mp4ff_read_int32(f);	/* reserved */
 
-	f->track[f->total_tracks - 1]->channelCount = mp4ff_read_int16(f);
-	f->track[f->total_tracks - 1]->sampleSize = mp4ff_read_int16(f);
+	t->channelCount = mp4ff_read_int16(f);
+	t->sampleSize = mp4ff_read_int16(f);
 
 	mp4ff_read_int16(f);
 	mp4ff_read_int16(f);
 
-	f->track[f->total_tracks - 1]->sampleRate = mp4ff_read_int16(f);
+	t->sampleRate = mp4ff_read_int16(f);
 
 	mp4ff_read_int16(f);
 
@@ -694,17 +677,20 @@ static int32_t mp4ff_read_stsd(mp4ff_t * f)
 {
 	int32_t i;
 	uint8_t header_size = 0;
+	mp4ff_track_t *t;
 
 	/* CVE-2017-9218 */
 	if (f->total_tracks == 0)
 		return f->error++;
+	t = f->track[f->total_tracks - 1];
 
 	mp4ff_read_char(f);	/* version */
 	mp4ff_read_int24(f);	/* flags */
 
-	f->track[f->total_tracks - 1]->stsd_entry_count = mp4ff_read_int32(f);
+	t->stsd_entry_count = mp4ff_read_int32(f);
 
-	for (i = 0; i < f->track[f->total_tracks - 1]->stsd_entry_count && !f->stream->read_error; i++) {	/* CVE-2017-9253 */
+	/* CVE-2017-9253 */
+	for (i = 0; i < t->stsd_entry_count && !f->stream->read_error; i++) {
 		uint64_t skip = mp4ff_position(f);
 		uint64_t size;
 		uint8_t atom_type = 0;
@@ -712,16 +698,15 @@ static int32_t mp4ff_read_stsd(mp4ff_t * f)
 		skip += size;
 
 		if (atom_type == ATOM_MP4A) {
-			f->track[f->total_tracks - 1]->type = TRACK_AUDIO;
+			t->type = TRACK_AUDIO;
 			mp4ff_read_mp4a(f);
 		} else if (atom_type == ATOM_MP4V) {
-			f->track[f->total_tracks - 1]->type = TRACK_VIDEO;
+			t->type = TRACK_VIDEO;
 		} else if (atom_type == ATOM_MP4S) {
-			f->track[f->total_tracks - 1]->type = TRACK_SYSTEM;
+			t->type = TRACK_SYSTEM;
 		} else {
-			f->track[f->total_tracks - 1]->type = TRACK_UNKNOWN;
+			t->type = TRACK_UNKNOWN;
 		}
-
 		mp4ff_set_position(f, skip);
 	}
 
@@ -1070,26 +1055,28 @@ static int32_t mp4ff_parse_tag(mp4ff_t * f, const uint8_t parent,
 static int32_t mp4ff_read_mdhd(mp4ff_t * f)
 {
 	uint32_t version;
+	mp4ff_track_t *t;
 
 	/* CVE-2017-9221 */
 	if (f->total_tracks == 0)
 		return f->error++;
+	t = f->track[f->total_tracks - 1];
 
 	version = mp4ff_read_int32(f);
 	if (version == 1) {
 		mp4ff_read_int64(f);	//creation-time
 		mp4ff_read_int64(f);	//modification-time
-		f->track[f->total_tracks - 1]->timeScale = mp4ff_read_int32(f);	//timescale
-		f->track[f->total_tracks - 1]->duration = mp4ff_read_int64(f);	//duration
-	} else			//version == 0
-	{
+		t->timeScale = mp4ff_read_int32(f); //timescale
+		t->duration = mp4ff_read_int64(f); //duration
+	} else { //version == 0
 		uint32_t temp;
 
 		mp4ff_read_int32(f);	//creation-time
 		mp4ff_read_int32(f);	//modification-time
-		f->track[f->total_tracks - 1]->timeScale = mp4ff_read_int32(f);	//timescale
+		t->timeScale = mp4ff_read_int32(f); //timescale
 		temp = mp4ff_read_int32(f);
-		f->track[f->total_tracks - 1]->duration = (temp == (uint32_t) (-1)) ? (uint64_t) (-1) : (uint64_t) (temp);
+		t->duration = (temp == (uint32_t) (-1))?
+			(uint64_t) (-1) : (uint64_t) (temp);
 	}
 	mp4ff_read_int16(f);
 	mp4ff_read_int16(f);