From: Andre Noll <maan@tuebingen.mpg.de>
Date: Fri, 27 Aug 2021 14:07:24 +0000 (+0200)
Subject: mp4: Remove E_MP4_BAD_CHANNEL_COUNT.
X-Git-Tag: v0.7.1~7^2~13
X-Git-Url: http://git.tue.mpg.de/?a=commitdiff_plain;h=84c7e6c683280d39a41155cc402f0ff2eafc7a0a;p=paraslash.git

mp4: Remove E_MP4_BAD_CHANNEL_COUNT.

If the mp4 file does not contain an m4a atom, the channel
count stays at zero and open_file() returns -E_MP4_TRACK in this
case. So the check in aac_afh.c for a non-positive return value from
mp4_get_channel_count() can never trigger. Replace the check by an
assertion and remove the error code.

Also, let mp4_get_channel_count() return uint16_t as the number of
channels is stored as an unsigned 16 bit number in the mp4 file.
---

diff --git a/aac_afh.c b/aac_afh.c
index de99613d..0f7f3fa9 100644
--- a/aac_afh.c
+++ b/aac_afh.c
@@ -139,11 +139,8 @@ static int aac_get_file_info(char *map, size_t numbytes, __a_unused int fd,
 		goto close;
 	afhi->frequency = rv;
 
-	ret = -E_MP4_BAD_CHANNEL_COUNT;
-	rv = mp4_get_channel_count(c->mp4);
-	if (rv <= 0)
-		goto close;
-	afhi->channels = rv;
+	afhi->channels = mp4_get_channel_count(c->mp4);
+	assert(afhi->channels > 0);
 
 	ret = -E_MP4_BAD_SAMPLE_COUNT;
 	rv = mp4_num_samples(c->mp4);
diff --git a/error.h b/error.h
index a4fe78a5..40081b6b 100644
--- a/error.h
+++ b/error.h
@@ -139,7 +139,6 @@
 	PARA_ERROR(MP3_INFO, "could not read mp3 info"), \
 	PARA_ERROR(MP4_READ, "mp4: read error or unexpected end of file"), \
 	PARA_ERROR(MP4_CORRUPT, "invalid/corrupt mp4 file"), \
-	PARA_ERROR(MP4_BAD_CHANNEL_COUNT, "mp4: invalid number of channels"), \
 	PARA_ERROR(MP4_BAD_SAMPLE, "mp4: invalid sample number"), \
 	PARA_ERROR(MP4_BAD_SAMPLERATE, "mp4: invalid sample rate"), \
 	PARA_ERROR(MP4_BAD_SAMPLE_COUNT, "mp4: invalid number of samples"), \
diff --git a/mp4.c b/mp4.c
index 205286a2..18f43925 100644
--- a/mp4.c
+++ b/mp4.c
@@ -698,7 +698,7 @@ uint32_t mp4_get_sample_rate(const struct mp4 *f)
 	return f->track.sample_rate;
 }
 
-uint32_t mp4_get_channel_count(const struct mp4 *f)
+uint16_t mp4_get_channel_count(const struct mp4 *f)
 {
 	return f->track.channel_count;
 }
diff --git a/mp4.h b/mp4.h
index 15cc6af9..5a07fadc 100644
--- a/mp4.h
+++ b/mp4.h
@@ -24,7 +24,7 @@ int mp4_open_read(const struct mp4_callback *cb, struct mp4 **result);
 void mp4_close(struct mp4 *f);
 int mp4_get_sample_size(const struct mp4 *f, uint32_t sample, uint32_t *result);
 uint32_t mp4_get_sample_rate(const struct mp4 *f);
-uint32_t mp4_get_channel_count(const struct mp4 * f);
+uint16_t mp4_get_channel_count(const struct mp4 *f);
 int32_t mp4_num_samples(const struct mp4 *f);
 uint64_t mp4_get_duration(const struct mp4 *f);
 int mp4_open_meta(const struct mp4_callback *cb, struct mp4 **result);