pcm/Format: change parameters/return values to ConstBuffer

src/pcm/FormatConverter.cxx

@@ -50,9 +50,6 @@ PcmFormatConverter::Close()
 ConstBuffer<void>
 PcmFormatConverter::Convert(ConstBuffer<void> src, Error &error)
 {
-	const void *result = nullptr;
-	size_t result_size = 0;
-
 	switch (dest_format) {
 	case SampleFormat::UNDEFINED:
 		assert(false);
@@ -60,45 +57,33 @@ PcmFormatConverter::Convert(ConstBuffer<void> src, Error &error)
 
 	case SampleFormat::S8:
 	case SampleFormat::DSD:
-		result = nullptr;
-		break;
+		error.Format(pcm_domain,
+			     "PCM conversion from %s to %s is not implemented",
+			     sample_format_to_string(src_format),
+			     sample_format_to_string(dest_format));
+		return nullptr;
 
 	case SampleFormat::S16:
-		result = pcm_convert_to_16(buffer, dither,
-					   src_format,
-					   src.data, src.size,
-					   &result_size);
-		break;
+		return pcm_convert_to_16(buffer, dither,
+					 src_format,
+					 src).ToVoid();
 
 	case SampleFormat::S24_P32:
-		result = pcm_convert_to_24(buffer,
-					   src_format,
-					   src.data, src.size,
-					   &result_size);
-		break;
+		return pcm_convert_to_24(buffer,
+					 src_format,
+					 src).ToVoid();
 
 	case SampleFormat::S32:
-		result = pcm_convert_to_32(buffer,
-					   src_format,
-					   src.data, src.size,
-					   &result_size);
-		break;
+		return pcm_convert_to_32(buffer,
+					 src_format,
+					 src).ToVoid();
 
 	case SampleFormat::FLOAT:
-		result = pcm_convert_to_float(buffer,
-					      src_format,
-					      src.data, src.size,
-					      &result_size);
-		break;
-	}
-
-	if (result == nullptr) {
-		error.Format(pcm_domain,
-			     "PCM conversion from %s to %s is not implemented",
-			     sample_format_to_string(src_format),
-			     sample_format_to_string(dest_format));
-		return nullptr;
+		return pcm_convert_to_float(buffer,
+					    src_format,
+					    src).ToVoid();
 	}
 
-	return { result, result_size };
+	assert(false);
+	gcc_unreachable();
 }

src/pcm/PcmFormat.hxx

@@ -25,6 +25,7 @@
 #include <stdint.h>
 #include <stddef.h>
 
+template<typename T> struct ConstBuffer;
 class PcmBuffer;
 class PcmDither;
 
@@ -36,14 +37,12 @@ class PcmDither;
  * @param dither a pcm_dither object for 24-to-16 conversion
  * @param bits the number of in the source buffer
  * @param src the source PCM buffer
- * @param src_size the size of #src in bytes
- * @param dest_size_r returns the number of bytes of the destination buffer
  * @return the destination buffer
  */
-const int16_t *
+gcc_pure
+ConstBuffer<int16_t>
 pcm_convert_to_16(PcmBuffer &buffer, PcmDither &dither,
-		  SampleFormat src_format, const void *src,
-		  size_t src_size, size_t *dest_size_r);
+		  SampleFormat src_format, ConstBuffer<void> src);
 
 /**
  * Converts PCM samples to 24 bit (32 bit alignment).
@@ -51,14 +50,12 @@ pcm_convert_to_16(PcmBuffer &buffer, PcmDither &dither,
  * @param buffer a PcmBuffer object
  * @param bits the number of in the source buffer
  * @param src the source PCM buffer
- * @param src_size the size of #src in bytes
- * @param dest_size_r returns the number of bytes of the destination buffer
  * @return the destination buffer
  */
-const int32_t *
+gcc_pure
+ConstBuffer<int32_t>
 pcm_convert_to_24(PcmBuffer &buffer,
-		  SampleFormat src_format, const void *src,
-		  size_t src_size, size_t *dest_size_r);
+		  SampleFormat src_format, ConstBuffer<void> src);
 
 /**
  * Converts PCM samples to 32 bit.
@@ -66,14 +63,12 @@ pcm_convert_to_24(PcmBuffer &buffer,
  * @param buffer a PcmBuffer object
  * @param bits the number of in the source buffer
  * @param src the source PCM buffer
- * @param src_size the size of #src in bytes
- * @param dest_size_r returns the number of bytes of the destination buffer
  * @return the destination buffer
  */
-const int32_t *
+gcc_pure
+ConstBuffer<int32_t>
 pcm_convert_to_32(PcmBuffer &buffer,
-		  SampleFormat src_format, const void *src,
-		  size_t src_size, size_t *dest_size_r);
+		  SampleFormat src_format, ConstBuffer<void> src);
 
 /**
  * Converts PCM samples to 32 bit floating point.
@@ -85,9 +80,9 @@ pcm_convert_to_32(PcmBuffer &buffer,
  * @param dest_size_r returns the number of bytes of the destination buffer
  * @return the destination buffer
  */
-const float *
+gcc_pure
+ConstBuffer<float>
 pcm_convert_to_float(PcmBuffer &buffer,
-		     SampleFormat src_format, const void *src,
-		     size_t src_size, size_t *dest_size_r);
+		     SampleFormat src_format, ConstBuffer<void> src);
 
 #endif

test/test_pcm_format.cxx

@@ -29,86 +29,72 @@
 void
 PcmFormatTest::TestFormat8to16()
 {
-	constexpr unsigned N = 256;
+	constexpr size_t N = 256;
 	const auto src = TestDataBuffer<int8_t, N>();
 
 	PcmBuffer buffer;
 
-	size_t d_size;
 	PcmDither dither;
-	auto d = pcm_convert_to_16(buffer, dither, SampleFormat::S8,
-				   src, sizeof(src), &d_size);
-	auto d_end = pcm_end_pointer(d, d_size);
-	CPPUNIT_ASSERT_EQUAL(N, unsigned(d_end - d));
+	auto d = pcm_convert_to_16(buffer, dither, SampleFormat::S8, src);
+	CPPUNIT_ASSERT_EQUAL(N, d.size);
 
 	for (size_t i = 0; i < N; ++i)
-		CPPUNIT_ASSERT_EQUAL(int(src[i]), d[i] >> 8);
+		CPPUNIT_ASSERT_EQUAL(int(src[i]), d.data[i] >> 8);
 }
 
 void
 PcmFormatTest::TestFormat16to24()
 {
-	constexpr unsigned N = 256;
+	constexpr size_t N = 256;
 	const auto src = TestDataBuffer<int16_t, N>();
 
 	PcmBuffer buffer;
 
-	size_t d_size;
-	auto d = pcm_convert_to_24(buffer, SampleFormat::S16,
-				   src, sizeof(src), &d_size);
-	auto d_end = pcm_end_pointer(d, d_size);
-	CPPUNIT_ASSERT_EQUAL(N, unsigned(d_end - d));
+	auto d = pcm_convert_to_24(buffer, SampleFormat::S16, src);
+	CPPUNIT_ASSERT_EQUAL(N, d.size);
 
 	for (size_t i = 0; i < N; ++i)
-		CPPUNIT_ASSERT_EQUAL(int(src[i]), d[i] >> 8);
+		CPPUNIT_ASSERT_EQUAL(int(src[i]), d.data[i] >> 8);
 }
 
 void
 PcmFormatTest::TestFormat16to32()
 {
-	constexpr unsigned N = 256;
+	constexpr size_t N = 256;
 	const auto src = TestDataBuffer<int16_t, N>();
 
 	PcmBuffer buffer;
 
-	size_t d_size;
-	auto d = pcm_convert_to_32(buffer, SampleFormat::S16,
-				   src, sizeof(src), &d_size);
-	auto d_end = pcm_end_pointer(d, d_size);
-	CPPUNIT_ASSERT_EQUAL(N, unsigned(d_end - d));
+	auto d = pcm_convert_to_32(buffer, SampleFormat::S16, src);
+	CPPUNIT_ASSERT_EQUAL(N, d.size);
 
 	for (size_t i = 0; i < N; ++i)
-		CPPUNIT_ASSERT_EQUAL(int(src[i]), d[i] >> 16);
+		CPPUNIT_ASSERT_EQUAL(int(src[i]), d.data[i] >> 16);
 }
 
 void
 PcmFormatTest::TestFormatFloat()
 {
-	constexpr unsigned N = 256;
+	constexpr size_t N = 256;
 	const auto src = TestDataBuffer<int16_t, N>();
 
 	PcmBuffer buffer1, buffer2;
 
-	size_t f_size;
-	auto f = pcm_convert_to_float(buffer1, SampleFormat::S16,
-				      src, sizeof(src), &f_size);
-	auto f_end = pcm_end_pointer(f, f_size);
-	CPPUNIT_ASSERT_EQUAL(N, unsigned(f_end - f));
+	auto f = pcm_convert_to_float(buffer1, SampleFormat::S16, src);
+	CPPUNIT_ASSERT_EQUAL(N, f.size);
 
-	for (auto i = f; i != f_end; ++i) {
-		CPPUNIT_ASSERT(*i >= -1.);
-		CPPUNIT_ASSERT(*i <= 1.);
+	for (size_t i = 0; i != f.size; ++i) {
+		CPPUNIT_ASSERT(f.data[i] >= -1.);
+		CPPUNIT_ASSERT(f.data[i] <= 1.);
 	}
 
 	PcmDither dither;
 
-	size_t d_size;
 	auto d = pcm_convert_to_16(buffer2, dither,
 				   SampleFormat::FLOAT,
-				   f, f_size, &d_size);
-	auto d_end = pcm_end_pointer(d, d_size);
-	CPPUNIT_ASSERT_EQUAL(N, unsigned(d_end - d));
+				   f.ToVoid());
+	CPPUNIT_ASSERT_EQUAL(N, d.size);
 
 	for (size_t i = 0; i < N; ++i)
-		CPPUNIT_ASSERT_EQUAL(src[i], d[i]);
+		CPPUNIT_ASSERT_EQUAL(src[i], d.data[i]);
 }

test/test_pcm_util.hxx

@@ -17,6 +17,8 @@
  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  */
 
+#include "util/ConstBuffer.hxx"
+
 #include <array>
 #include <random>
 
@@ -76,6 +78,14 @@ public:
 	operator typename std::array<T, N>::const_pointer() const {
 		return begin();
 	}
+
+	operator ConstBuffer<T>() const {
+		return { begin(), size() };
+	}
+
+	operator ConstBuffer<void>() const {
+		return { begin(), size() * sizeof(T) };
+	}
 };
 
 template<typename T>