pcm_byteswap: add function with sample_format overload

src/pcm_byteswap.c

@@ -68,3 +68,29 @@ const int32_t *pcm_byteswap_32(struct pcm_buffer *buffer,
 
 	return buf;
 }
+
+const void *
+pcm_byteswap(struct pcm_buffer *buffer, enum sample_format format,
+	     const void *src, size_t size)
+{
+	switch (format) {
+	case SAMPLE_FORMAT_UNDEFINED:
+	case SAMPLE_FORMAT_S24:
+		/* not implemented */
+		return NULL;
+
+	case SAMPLE_FORMAT_S8:
+		return src;
+
+	case SAMPLE_FORMAT_S16:
+		return pcm_byteswap_16(buffer, src, size);
+
+	case SAMPLE_FORMAT_S24_P32:
+	case SAMPLE_FORMAT_S32:
+		return pcm_byteswap_32(buffer, src, size);
+	}
+
+	/* unreachable */
+	assert(false);
+	return NULL;
+}

src/pcm_byteswap.h

@@ -20,6 +20,8 @@
 #ifndef MPD_PCM_BYTESWAP_H
 #define MPD_PCM_BYTESWAP_H
 
+#include "audio_format.h"
+
 #include <stdint.h>
 #include <stddef.h>
 
@@ -47,4 +49,19 @@ const int16_t *pcm_byteswap_16(struct pcm_buffer *buffer,
 const int32_t *pcm_byteswap_32(struct pcm_buffer *buffer,
 			       const int32_t *src, size_t len);
 
+/**
+ * Changes the endianness of PCM data.
+ *
+ * @param buffer the destination pcm_buffer object
+ * @param format the sample format (both input and output)
+ * @param src the source PCM buffer
+ * @param src_size the number of bytes in #src
+ * @return the destination buffer, or NULL if the sample format is not
+ * supported
+ */
+G_GNUC_MALLOC
+const void *
+pcm_byteswap(struct pcm_buffer *buffer, enum sample_format format,
+	     const void *src, size_t size);
+
 #endif