From d84e86da9cc7494f5e28b88b39b058c86eb7c974 Mon Sep 17 00:00:00 2001
From: Urs Fleisch <ufleisch@users.sourceforge.net>
Date: Tue, 22 Dec 2020 08:22:49 +0100
Subject: [PATCH] Clean up code to better match the TagLib style
---
taglib/wavpack/wavpackproperties.cpp | 220 +++++++++++++--------------
taglib/wavpack/wavpackproperties.h | 2 -
2 files changed, 106 insertions(+), 116 deletions(-)
diff --git a/taglib/wavpack/wavpackproperties.cpp b/taglib/wavpack/wavpackproperties.cpp
index 8d7ab9ea..d5808be5 100644
--- a/taglib/wavpack/wavpackproperties.cpp
+++ b/taglib/wavpack/wavpackproperties.cpp
@@ -27,6 +27,7 @@
* http://www.mozilla.org/MPL/ *
***************************************************************************/
+#include <stdint.h>
#include <tstring.h>
#include <tdebug.h>
@@ -138,13 +139,6 @@ unsigned int WavPack::Properties::sampleFrames() const
// private members
////////////////////////////////////////////////////////////////////////////////
-namespace
-{
- const unsigned int sample_rates[] = {
- 6000, 8000, 9600, 11025, 12000, 16000, 22050, 24000,
- 32000, 44100, 48000, 64000, 88200, 96000, 192000, 0 };
-}
-
#define BYTES_STORED 3
#define MONO_FLAG 4
#define HYBRID_FLAG 8
@@ -169,6 +163,100 @@ namespace
#define ID_LARGE 0x80
#define ID_SAMPLE_RATE (ID_OPTIONAL_DATA | 0x7)
+namespace
+{
+ const unsigned int sampleRates[] = {
+ 6000, 8000, 9600, 11025, 12000, 16000, 22050, 24000,
+ 32000, 44100, 48000, 64000, 88200, 96000, 192000, 0 };
+
+ /*!
+ * Given a WavPack \a block (complete, but not including the 32-byte header),
+ * parse the metadata blocks until an \a id block is found and return the
+ * contained data, or zero if no such block is found.
+ * Supported values for \a id are ID_SAMPLE_RATE and ID_DSD_BLOCK.
+ */
+ int getMetaDataChunk(const ByteVector &block, unsigned char id)
+ {
+ if(id != ID_SAMPLE_RATE && id != ID_DSD_BLOCK)
+ return 0;
+
+ const int blockSize = static_cast<int>(block.size());
+ int index = 0;
+
+ while(index + 1 < blockSize) {
+ const unsigned char metaId = static_cast<unsigned char>(block[index]);
+ int metaBc = static_cast<unsigned char>(block[index + 1]) << 1;
+ index += 2;
+
+ if(metaId & ID_LARGE) {
+ if(index + 2 > blockSize)
+ return 0;
+
+ metaBc += (static_cast<uint32_t>(static_cast<unsigned char>(block[index])) << 9)
+ + (static_cast<uint32_t>(static_cast<unsigned char>(block[index + 1])) << 17);
+ index += 2;
+ }
+
+ if(index + metaBc > blockSize)
+ return 0;
+
+ // if we got a sample rate, return it
+
+ if(id == ID_SAMPLE_RATE && (metaId & ID_UNIQUE) == ID_SAMPLE_RATE && metaBc == 4) {
+ int sampleRate = static_cast<int32_t>(static_cast<unsigned char>(block[index]));
+ sampleRate |= static_cast<int32_t>(static_cast<unsigned char>(block[index + 1])) << 8;
+ sampleRate |= static_cast<int32_t>(static_cast<unsigned char>(block[index + 2])) << 16;
+
+ // only use 4th byte if it's really there
+
+ if(!(metaId & ID_ODD_SIZE))
+ sampleRate |= static_cast<int32_t>(static_cast<unsigned char>(block[index + 3]) & 0x7f) << 24;
+
+ return sampleRate;
+ }
+
+ // if we got DSD block, return the specified rate shift amount
+
+ if(id == ID_DSD_BLOCK && (metaId & ID_UNIQUE) == ID_DSD_BLOCK && metaBc > 0) {
+ const unsigned char rateShift = static_cast<unsigned char>(block[index]);
+ if(rateShift <= 31)
+ return rateShift;
+ }
+
+ index += metaBc;
+ }
+
+ return 0;
+ }
+
+ /*!
+ * Given a WavPack block (complete, but not including the 32-byte header),
+ * parse the metadata blocks until an ID_SAMPLE_RATE block is found and
+ * return the non-standard sample rate contained there, or zero if no such
+ * block is found.
+ */
+ int getNonStandardRate(const ByteVector &block)
+ {
+ return getMetaDataChunk(block, ID_SAMPLE_RATE);
+ }
+
+ /*!
+ * Given a WavPack block (complete, but not including the 32-byte header),
+ * parse the metadata blocks until a DSD audio data block is found and return
+ * the sample-rate shift value contained there, or zero if no such block is
+ * found. The nominal sample rate of DSD audio files (found in the header)
+ * must be left-shifted by this amount to get the actual "byte" sample rate.
+ * Note that 8-bit bytes are the "atoms" of the DSD audio coding (for
+ * decoding, seeking, etc), so the shifted rate must be further multiplied by
+ * 8 to get the actual DSD bit sample rate.
+ */
+ int getDsdRateShifter(const ByteVector &block)
+ {
+ return getMetaDataChunk(block, ID_DSD_BLOCK);
+ }
+
+}
+
void WavPack::Properties::read(File *file, long streamLength)
{
long offset = 0;
@@ -191,14 +279,14 @@ void WavPack::Properties::read(File *file, long streamLength)
const unsigned int sampleFrames = data.toUInt(12, false);
const unsigned int blockSamples = data.toUInt(20, false);
const unsigned int flags = data.toUInt(24, false);
- unsigned int sampleRate = sample_rates[(flags & SRATE_MASK) >> SRATE_LSB];
+ unsigned int sampleRate = sampleRates[(flags & SRATE_MASK) >> SRATE_LSB];
- if (!blockSamples) { // ignore blocks with no samples
+ if(!blockSamples) { // ignore blocks with no samples
offset += blockSize + 8;
continue;
}
- if (blockSize < 24 || blockSize > 1048576) {
+ if(blockSize < 24 || blockSize > 1048576) {
debug("WavPack::Properties::read() -- Invalid block header found.");
break;
}
@@ -207,19 +295,19 @@ void WavPack::Properties::read(File *file, long streamLength)
// to actually determine the sample rate.
if(!sampleRate || (flags & DSD_FLAG)) {
- const unsigned int adjusted_block_size = blockSize - 24;
- const ByteVector block = file->readBlock(adjusted_block_size);
+ const unsigned int adjustedBlockSize = blockSize - 24;
+ const ByteVector block = file->readBlock(adjustedBlockSize);
- if(block.size() < adjusted_block_size) {
+ if(block.size() < adjustedBlockSize) {
debug("WavPack::Properties::read() -- block is too short.");
break;
}
- if (!sampleRate)
- sampleRate = getNonStandardRate(reinterpret_cast<unsigned char const*>(block.data()), adjusted_block_size);
+ if(!sampleRate)
+ sampleRate = static_cast<unsigned int>(getNonStandardRate(block));
- if (sampleRate && (flags & DSD_FLAG))
- sampleRate <<= getDsdRateShifter(reinterpret_cast<unsigned char const*>(block.data()), adjusted_block_size);
+ if(sampleRate && (flags & DSD_FLAG))
+ sampleRate <<= getDsdRateShifter(block);
}
if(flags & INITIAL_BLOCK) {
@@ -228,7 +316,7 @@ void WavPack::Properties::read(File *file, long streamLength)
break;
d->bitsPerSample = ((flags & BYTES_STORED) + 1) * 8 - ((flags & SHIFT_MASK) >> SHIFT_LSB);
- d->sampleRate = sampleRate;
+ d->sampleRate = static_cast<int>(sampleRate);
d->lossless = !(flags & HYBRID_FLAG);
d->sampleFrames = sampleFrames;
}
@@ -284,99 +372,3 @@ unsigned int WavPack::Properties::seekFinalIndex(File *file, long streamLength)
return 0;
}
-
-// Given a WavPack block (complete, but not including the 32-byte header), parse the metadata
-// blocks until an ID_SAMPLE_RATE block is found and return the non-standard sample rate
-// contained there, or zero if no such block is found.
-
-int WavPack::Properties::getNonStandardRate(unsigned char const *buffer, int bcount)
-{
- unsigned char meta_id, c1, c2;
- int meta_bc;
-
- while (bcount >= 2) {
- meta_id = *buffer++;
- c1 = *buffer++;
-
- meta_bc = c1 << 1;
- bcount -= 2;
-
- if (meta_id & ID_LARGE) {
- if (bcount < 2)
- return 0;
-
- c1 = *buffer++;
- c2 = *buffer++;
- meta_bc += (static_cast<uint32_t>(c1) << 9) + (static_cast<uint32_t>(c2) << 17);
- bcount -= 2;
- }
-
- if (bcount < meta_bc)
- return 0;
-
- // if we got a sample rate, return it
-
- if ((meta_id & ID_UNIQUE) == ID_SAMPLE_RATE && meta_bc == 4) {
- int sample_rate = static_cast<int32_t>(*buffer++);
- sample_rate |= static_cast<int32_t>(*buffer++) << 8;
- sample_rate |= static_cast<int32_t>(*buffer++) << 16;
-
- // only use 4th byte if it's really there
-
- if (!(meta_id & ID_ODD_SIZE))
- sample_rate |= static_cast<int32_t>(*buffer & 0x7f) << 24;
-
- return sample_rate;
- }
-
- bcount -= meta_bc;
- buffer += meta_bc;
- }
-
- return 0;
-}
-
-// Given a WavPack block (complete, but not including the 32-byte header), parse the metadata
-// blocks until a DSD audio data block is found and return the sample-rate shift value
-// contained there, or zero if no such block is found. The nominal sample rate of DSD audio
-// files (found in the header) must be left-shifted by this amount to get the actual "byte"
-// sample rate. Note that 8-bit bytes are the "atoms" of the DSD audio coding (for decoding,
-// seeking, etc), so the shifted rate must be further multiplied by 8 to get the actual DSD
-// bit sample rate.
-
-int WavPack::Properties::getDsdRateShifter(unsigned char const *buffer, int bcount)
-{
- unsigned char meta_id, c1, c2;
- int meta_bc;
-
- while (bcount >= 2) {
- meta_id = *buffer++;
- c1 = *buffer++;
-
- meta_bc = c1 << 1;
- bcount -= 2;
-
- if (meta_id & ID_LARGE) {
- if (bcount < 2)
- return 0;
-
- c1 = *buffer++;
- c2 = *buffer++;
- meta_bc += (static_cast<uint32_t>(c1) << 9) + (static_cast<uint32_t>(c2) << 17);
- bcount -= 2;
- }
-
- if (bcount < meta_bc)
- return 0;
-
- // if we got DSD block, return the specified rate shift amount
-
- if ((meta_id & ID_UNIQUE) == ID_DSD_BLOCK && meta_bc && *buffer <= 31)
- return *buffer;
-
- bcount -= meta_bc;
- buffer += meta_bc;
- }
-
- return 0;
-}
diff --git a/taglib/wavpack/wavpackproperties.h b/taglib/wavpack/wavpackproperties.h
index ddc51f7d..e6acdcc3 100644
--- a/taglib/wavpack/wavpackproperties.h
+++ b/taglib/wavpack/wavpackproperties.h
@@ -139,8 +139,6 @@ namespace TagLib {
void read(File *file, long streamLength);
unsigned int seekFinalIndex(File *file, long streamLength);
- int getNonStandardRate(unsigned char const *buffer, int bcount);
- int getDsdRateShifter(unsigned char const *buffer, int bcount);
class PropertiesPrivate;
PropertiesPrivate *d;