pcm_channels: pass an "end" pointer instead of a sample count

src/pcm_channels.c

@@ -20,14 +20,15 @@
 #include "config.h"
 #include "pcm_channels.h"
 #include "pcm_buffer.h"
+#include "pcm_utils.h"
 
 #include <assert.h>
 
 static void
 pcm_convert_channels_16_1_to_2(int16_t *dest, const int16_t *src,
-			       unsigned num_frames)
+			       const int16_t *src_end)
 {
-	while (num_frames-- > 0) {
+	while (src < src_end) {
 		int16_t value = *src++;
 
 		*dest++ = value;
@@ -37,9 +38,9 @@ pcm_convert_channels_16_1_to_2(int16_t *dest, const int16_t *src,
 
 static void
 pcm_convert_channels_16_2_to_1(int16_t *dest, const int16_t *src,
-			       unsigned num_frames)
+			       const int16_t *src_end)
 {
-	while (num_frames-- > 0) {
+	while (src < src_end) {
 		int32_t a = *src++, b = *src++;
 
 		*dest++ = (a + b) / 2;
@@ -49,13 +50,13 @@ pcm_convert_channels_16_2_to_1(int16_t *dest, const int16_t *src,
 static void
 pcm_convert_channels_16_n_to_2(int16_t *dest,
 			       unsigned src_channels, const int16_t *src,
-			       unsigned num_frames)
+			       const int16_t *src_end)
 {
 	unsigned c;
 
 	assert(src_channels > 0);
 
-	while (num_frames-- > 0) {
+	while (src < src_end) {
 		int32_t sum = 0;
 		int16_t value;
 
@@ -77,19 +78,19 @@ pcm_convert_channels_16(struct pcm_buffer *buffer,
 {
 	assert(src_size % (sizeof(*src) * src_channels) == 0);
 
-	unsigned num_frames = src_size / src_channels / sizeof(*src);
+	size_t dest_size = src_size / src_channels * dest_channels;
-	unsigned dest_size = num_frames * dest_channels * sizeof(*src);
-	int16_t *dest = pcm_buffer_get(buffer, dest_size);
-
 	*dest_size_r = dest_size;
 
+	int16_t *dest = pcm_buffer_get(buffer, dest_size);
+	const int16_t *src_end = pcm_end_pointer(src, src_size);
+
 	if (src_channels == 1 && dest_channels == 2)
-		pcm_convert_channels_16_1_to_2(dest, src, num_frames);
+		pcm_convert_channels_16_1_to_2(dest, src, src_end);
 	else if (src_channels == 2 && dest_channels == 1)
-		pcm_convert_channels_16_2_to_1(dest, src, num_frames);
+		pcm_convert_channels_16_2_to_1(dest, src, src_end);
 	else if (dest_channels == 2)
 		pcm_convert_channels_16_n_to_2(dest, src_channels, src,
-					       num_frames);
+					       src_end);
 	else
 		return NULL;
 
@@ -98,9 +99,9 @@ pcm_convert_channels_16(struct pcm_buffer *buffer,
 
 static void
 pcm_convert_channels_24_1_to_2(int32_t *dest, const int32_t *src,
-			       unsigned num_frames)
+			       const int32_t *src_end)
 {
-	while (num_frames-- > 0) {
+	while (src < src_end) {
 		int32_t value = *src++;
 
 		*dest++ = value;
@@ -110,9 +111,9 @@ pcm_convert_channels_24_1_to_2(int32_t *dest, const int32_t *src,
 
 static void
 pcm_convert_channels_24_2_to_1(int32_t *dest, const int32_t *src,
-			       unsigned num_frames)
+			       const int32_t *src_end)
 {
-	while (num_frames-- > 0) {
+	while (src < src_end) {
 		int32_t a = *src++, b = *src++;
 
 		*dest++ = (a + b) / 2;
@@ -122,13 +123,13 @@ pcm_convert_channels_24_2_to_1(int32_t *dest, const int32_t *src,
 static void
 pcm_convert_channels_24_n_to_2(int32_t *dest,
 			       unsigned src_channels, const int32_t *src,
-			       unsigned num_frames)
+			       const int32_t *src_end)
 {
 	unsigned c;
 
 	assert(src_channels > 0);
 
-	while (num_frames-- > 0) {
+	while (src < src_end) {
 		int32_t sum = 0;
 		int32_t value;
 
@@ -150,19 +151,19 @@ pcm_convert_channels_24(struct pcm_buffer *buffer,
 {
 	assert(src_size % (sizeof(*src) * src_channels) == 0);
 
-	unsigned num_frames = src_size / src_channels / sizeof(*src);
+	size_t dest_size = src_size / src_channels * dest_channels;
-	unsigned dest_size = num_frames * dest_channels * sizeof(*src);
-	int32_t *dest = pcm_buffer_get(buffer, dest_size);
-
 	*dest_size_r = dest_size;
 
+	int32_t *dest = pcm_buffer_get(buffer, dest_size);
+	const int32_t *src_end = pcm_end_pointer(src, src_size);
+
 	if (src_channels == 1 && dest_channels == 2)
-		pcm_convert_channels_24_1_to_2(dest, src, num_frames);
+		pcm_convert_channels_24_1_to_2(dest, src, src_end);
 	else if (src_channels == 2 && dest_channels == 1)
-		pcm_convert_channels_24_2_to_1(dest, src, num_frames);
+		pcm_convert_channels_24_2_to_1(dest, src, src_end);
 	else if (dest_channels == 2)
 		pcm_convert_channels_24_n_to_2(dest, src_channels, src,
-					       num_frames);
+					       src_end);
 	else
 		return NULL;
 
@@ -171,16 +172,16 @@ pcm_convert_channels_24(struct pcm_buffer *buffer,
 
 static void
 pcm_convert_channels_32_1_to_2(int32_t *dest, const int32_t *src,
-			       unsigned num_frames)
+			       const int32_t *src_end)
 {
-	pcm_convert_channels_24_1_to_2(dest, src, num_frames);
+	pcm_convert_channels_24_1_to_2(dest, src, src_end);
 }
 
 static void
 pcm_convert_channels_32_2_to_1(int32_t *dest, const int32_t *src,
-			       unsigned num_frames)
+			       const int32_t *src_end)
 {
-	while (num_frames-- > 0) {
+	while (src < src_end) {
 		int64_t a = *src++, b = *src++;
 
 		*dest++ = (a + b) / 2;
@@ -190,13 +191,13 @@ pcm_convert_channels_32_2_to_1(int32_t *dest, const int32_t *src,
 static void
 pcm_convert_channels_32_n_to_2(int32_t *dest,
 			       unsigned src_channels, const int32_t *src,
-			       unsigned num_frames)
+			       const int32_t *src_end)
 {
 	unsigned c;
 
 	assert(src_channels > 0);
 
-	while (num_frames-- > 0) {
+	while (src < src_end) {
 		int64_t sum = 0;
 		int32_t value;
 
@@ -218,19 +219,19 @@ pcm_convert_channels_32(struct pcm_buffer *buffer,
 {
 	assert(src_size % (sizeof(*src) * src_channels) == 0);
 
-	unsigned num_frames = src_size / src_channels / sizeof(*src);
+	size_t dest_size = src_size / src_channels * dest_channels;
-	unsigned dest_size = num_frames * dest_channels * sizeof(*src);
-	int32_t *dest = pcm_buffer_get(buffer, dest_size);
-
 	*dest_size_r = dest_size;
 
+	int32_t *dest = pcm_buffer_get(buffer, dest_size);
+	const int32_t *src_end = pcm_end_pointer(src, src_size);
+
 	if (src_channels == 1 && dest_channels == 2)
-		pcm_convert_channels_32_1_to_2(dest, src, num_frames);
+		pcm_convert_channels_32_1_to_2(dest, src, src_end);
 	else if (src_channels == 2 && dest_channels == 1)
-		pcm_convert_channels_32_2_to_1(dest, src, num_frames);
+		pcm_convert_channels_32_2_to_1(dest, src, src_end);
 	else if (dest_channels == 2)
 		pcm_convert_channels_32_n_to_2(dest, src_channels, src,
-					       num_frames);
+					       src_end);
 	else
 		return NULL;