From c93f610da7ffa9a672e70242ebd08c5093e33665 Mon Sep 17 00:00:00 2001
From: Andre Noll <maan@tuebingen.mpg.de>
Date: Mon, 9 Aug 2021 19:59:41 +0200
Subject: [PATCH] mp4: free(NULL) is OK.

Also remove a initialization to NULL after the free() because it is
immediately followed by an assignment to the same variable.
---
 mp4.c | 72 +++++++++++++++++++----------------------------------------
 1 file changed, 23 insertions(+), 49 deletions(-)

diff --git a/mp4.c b/mp4.c
index 576f1574..9b09a8f4 100644
--- a/mp4.c
+++ b/mp4.c
@@ -644,8 +644,7 @@ static int32_t mp4ff_read_esds(mp4ff_t * f)
 	f->track[f->total_tracks - 1]->decoderConfigLen =
 		mp4ff_read_mp4_descr_length(f);
 
-	if (f->track[f->total_tracks - 1]->decoderConfig)
-		free(f->track[f->total_tracks - 1]->decoderConfig);
+	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) {
@@ -771,8 +770,7 @@ static int32_t mp4ff_tag_add_field(mp4ff_metadata_t * tags, const char *item,
 	tags->tags = (mp4ff_tag_t *) realloc(tags->tags,
 		(tags->count + 1) * sizeof (mp4ff_tag_t));
 	if (!tags->tags) {
-		if (backup)
-			free(backup);
+		free(backup);
 		return 0;
 	} else {
 		tags->tags[tags->count].item = strdup(item);
@@ -786,10 +784,8 @@ static int32_t mp4ff_tag_add_field(mp4ff_metadata_t * tags, const char *item,
 		}
 
 		if (!tags->tags[tags->count].item || !tags->tags[tags->count].value) {
-			if (!tags->tags[tags->count].item)
-				free(tags->tags[tags->count].item);
-			if (!tags->tags[tags->count].value)
-				free(tags->tags[tags->count].value);
+			free(tags->tags[tags->count].item);
+			free(tags->tags[tags->count].value);
 			tags->tags[tags->count].item = NULL;
 			tags->tags[tags->count].value = NULL;
 			tags->tags[tags->count].len = 0;
@@ -1034,10 +1030,7 @@ static int32_t mp4ff_parse_tag(mp4ff_t * f, const uint8_t parent_atom_type,
 					done = 1;
 				}
 			} else {
-				if (data) {
-					free(data);
-					data = NULL;
-				}
+				free(data);
 				data = mp4ff_read_string(f, (uint32_t) (subsize - (header_size + 8)));
 				len = (uint32_t) (subsize - (header_size + 8));
 			}
@@ -1045,8 +1038,7 @@ static int32_t mp4ff_parse_tag(mp4ff_t * f, const uint8_t parent_atom_type,
 			if (!done) {
 				mp4ff_read_char(f);	/* version */
 				mp4ff_read_int24(f);	/* flags */
-				if (name)
-					free(name);
+				free(name);
 				name = mp4ff_read_string(f, (uint32_t) (subsize - (header_size + 4)));
 			}
 		}
@@ -1064,10 +1056,10 @@ static int32_t mp4ff_parse_tag(mp4ff_t * f, const uint8_t parent_atom_type,
 
 		free(data);
 	}
-	if (name)
-		free(name);
+	free(name);
 	return 1;
 }
+
 static int32_t mp4ff_read_mdhd(mp4ff_t * f)
 {
 	uint32_t version;
@@ -1288,15 +1280,10 @@ static int32_t mp4ff_tag_delete(mp4ff_metadata_t * tags)
 	uint32_t i;
 
 	for (i = 0; i < tags->count; i++) {
-		if (tags->tags[i].item)
-			free(tags->tags[i].item);
-		if (tags->tags[i].value)
-			free(tags->tags[i].value);
+		free(tags->tags[i].item);
+		free(tags->tags[i].value);
 	}
-
-	if (tags->tags)
-		free(tags->tags);
-
+	free(tags->tags);
 	tags->tags = NULL;
 	tags->count = 0;
 
@@ -1309,34 +1296,22 @@ void mp4ff_close(mp4ff_t * ff)
 
 	for (i = 0; i < ff->total_tracks; i++) {
 		if (ff->track[i]) {
-			if (ff->track[i]->stsz_table)
-				free(ff->track[i]->stsz_table);
-			if (ff->track[i]->stts_sample_count)
-				free(ff->track[i]->stts_sample_count);
-			if (ff->track[i]->stts_sample_delta)
-				free(ff->track[i]->stts_sample_delta);
-			if (ff->track[i]->stsc_first_chunk)
-				free(ff->track[i]->stsc_first_chunk);
-			if (ff->track[i]->stsc_samples_per_chunk)
-				free(ff->track[i]->stsc_samples_per_chunk);
-			if (ff->track[i]->stsc_sample_desc_index)
-				free(ff->track[i]->stsc_sample_desc_index);
-			if (ff->track[i]->stco_chunk_offset)
-				free(ff->track[i]->stco_chunk_offset);
-			if (ff->track[i]->decoderConfig)
-				free(ff->track[i]->decoderConfig);
-			if (ff->track[i]->ctts_sample_count)
-				free(ff->track[i]->ctts_sample_count);
-			if (ff->track[i]->ctts_sample_offset)
-				free(ff->track[i]->ctts_sample_offset);
+			free(ff->track[i]->stsz_table);
+			free(ff->track[i]->stts_sample_count);
+			free(ff->track[i]->stts_sample_delta);
+			free(ff->track[i]->stsc_first_chunk);
+			free(ff->track[i]->stsc_samples_per_chunk);
+			free(ff->track[i]->stsc_sample_desc_index);
+			free(ff->track[i]->stco_chunk_offset);
+			free(ff->track[i]->decoderConfig);
+			free(ff->track[i]->ctts_sample_count);
+			free(ff->track[i]->ctts_sample_offset);
 			free(ff->track[i]);
 		}
 	}
 
 	mp4ff_tag_delete(&(ff->tags));
-
-	if (ff)
-		free(ff);
+	free(ff);
 }
 
 static int32_t mp4ff_chunk_of_sample(const mp4ff_t * f, const int32_t track,
@@ -1773,8 +1748,7 @@ static unsigned membuffer_error(const membuffer * buf)
 
 static void membuffer_free(membuffer * buf)
 {
-	if (buf->data)
-		free(buf->data);
+	free(buf->data);
 	free(buf);
 }
 
-- 
2.39.5