/*
* Copyright (C) 2012 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <audio_utils/sndfile.h>
#include <audio_utils/primitives.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#define WAVE_FORMAT_PCM 1
#define WAVE_FORMAT_IEEE_FLOAT 3
#define WAVE_FORMAT_EXTENSIBLE 0xFFFE
struct SNDFILE_ {
int mode;
uint8_t *temp; // realloc buffer used for shrinking 16 bits to 8 bits and byte-swapping
FILE *stream;
size_t bytesPerFrame;
size_t remaining; // frames unread for SFM_READ, frames written for SFM_WRITE
SF_INFO info;
};
static unsigned little2u(unsigned char *ptr)
{
return (ptr[1] << 8) + ptr[0];
}
static unsigned little4u(unsigned char *ptr)
{
return (ptr[3] << 24) + (ptr[2] << 16) + (ptr[1] << 8) + ptr[0];
}
static int isLittleEndian(void)
{
static const short one = 1;
return *((const char *) &one) == 1;
}
// "swab" conflicts with OS X <string.h>
static void my_swab(short *ptr, size_t numToSwap)
{
while (numToSwap > 0) {
*ptr = little2u((unsigned char *) ptr);
--numToSwap;
++ptr;
}
}
static SNDFILE *sf_open_read(const char *path, SF_INFO *info)
{
FILE *stream = fopen(path, "rb");
if (stream == NULL) {
fprintf(stderr, "fopen %s failed errno %d\n", path, errno);
return NULL;
}
SNDFILE *handle = (SNDFILE *) malloc(sizeof(SNDFILE));
handle->mode = SFM_READ;
handle->temp = NULL;
handle->stream = stream;
handle->info.format = SF_FORMAT_WAV;
// don't attempt to parse all valid forms, just the most common ones
unsigned char wav[12];
size_t actual;
actual = fread(wav, sizeof(char), sizeof(wav), stream);
if (actual < 12) {
fprintf(stderr, "actual %u < 44\n", actual);
goto close;
}
if (memcmp(wav, "RIFF", 4)) {
fprintf(stderr, "wav != RIFF\n");
goto close;
}
unsigned riffSize = little4u(&wav[4]);
if (riffSize < 4) {
fprintf(stderr, "riffSize %u < 4\n", riffSize);
goto close;
}
if (memcmp(&wav[8], "WAVE", 4)) {
fprintf(stderr, "missing WAVE\n");
goto close;
}
size_t remaining = riffSize - 4;
int hadFmt = 0;
int hadData = 0;
while (remaining >= 8) {
unsigned char chunk[8];
actual = fread(chunk, sizeof(char), sizeof(chunk), stream);
if (actual != sizeof(chunk)) {
fprintf(stderr, "actual %u != %u\n", actual, sizeof(chunk));
goto close;
}
remaining -= 8;
unsigned chunkSize = little4u(&chunk[4]);
if (chunkSize > remaining) {
fprintf(stderr, "chunkSize %u > remaining %u\n", chunkSize, remaining);
goto close;
}
if (!memcmp(&chunk[0], "fmt ", 4)) {
if (hadFmt) {
fprintf(stderr, "multiple fmt\n");
goto close;
}
if (chunkSize < 2) {
fprintf(stderr, "chunkSize %u < 2\n", chunkSize);
goto close;
}
unsigned char fmt[40];
actual = fread(fmt, sizeof(char), 2, stream);
if (actual != 2) {
fprintf(stderr, "actual %u != 2\n", actual);
goto close;
}
unsigned format = little2u(&fmt[0]);
size_t minSize = 0;
switch (format) {
case WAVE_FORMAT_PCM:
case WAVE_FORMAT_IEEE_FLOAT:
minSize = 16;
break;
case WAVE_FORMAT_EXTENSIBLE:
minSize = 40;
break;
default:
fprintf(stderr, "unsupported format %u\n", format);
goto close;
}
if (chunkSize < minSize) {
fprintf(stderr, "chunkSize %u < minSize %u\n", chunkSize, minSize);
goto close;
}
actual = fread(&fmt[2], sizeof(char), minSize - 2, stream);
if (actual != minSize - 2) {
fprintf(stderr, "actual %u != %u\n", actual, minSize - 16);
goto close;
}
if (chunkSize > minSize) {
fseek(stream, (long) (chunkSize - minSize), SEEK_CUR);
}
unsigned channels = little2u(&fmt[2]);
if (channels != 1 && channels != 2) {
fprintf(stderr, "channels %u != 1 or 2\n", channels);
goto close;
}
unsigned samplerate = little4u(&fmt[4]);
if (samplerate == 0) {
fprintf(stderr, "samplerate %u == 0\n", samplerate);
goto close;
}
// ignore byte rate
// ignore block alignment
unsigned bitsPerSample = little2u(&fmt[14]);
if (bitsPerSample != 8 && bitsPerSample != 16 && bitsPerSample != 32) {
fprintf(stderr, "bitsPerSample %u != 8 or 16 or 32\n", bitsPerSample);
goto close;
}
unsigned bytesPerFrame = (bitsPerSample >> 3) * channels;
handle->bytesPerFrame = bytesPerFrame;
handle->info.samplerate = samplerate;
handle->info.channels = channels;
switch (bitsPerSample) {
case 8:
handle->info.format |= SF_FORMAT_PCM_U8;
break;
case 16:
handle->info.format |= SF_FORMAT_PCM_16;
break;
case 32:
if (format == WAVE_FORMAT_IEEE_FLOAT)
handle->info.format |= SF_FORMAT_FLOAT;
else
handle->info.format |= SF_FORMAT_PCM_32;
break;
}
hadFmt = 1;
} else if (!memcmp(&chunk[0], "data", 4)) {
if (!hadFmt) {
fprintf(stderr, "data not preceded by fmt\n");
goto close;
}
if (hadData) {
fprintf(stderr, "multiple data\n");
goto close;
}
handle->remaining = chunkSize / handle->bytesPerFrame;
handle->info.frames = handle->remaining;
hadData = 1;
} else if (!memcmp(&chunk[0], "fact", 4)) {
// ignore fact
if (chunkSize > 0) {
fseek(stream, (long) chunkSize, SEEK_CUR);
}
} else {
// ignore unknown chunk
fprintf(stderr, "ignoring unknown chunk %c%c%c%c\n",
chunk[0], chunk[1], chunk[2], chunk[3]);
if (chunkSize > 0) {
fseek(stream, (long) chunkSize, SEEK_CUR);
}
}
remaining -= chunkSize;
}
if (remaining > 0) {
fprintf(stderr, "partial chunk at end of RIFF, remaining %u\n", remaining);
goto close;
}
if (!hadData) {
fprintf(stderr, "missing data\n");
goto close;
}
*info = handle->info;
return handle;
close:
free(handle);
fclose(stream);
return NULL;
}
static void write4u(unsigned char *ptr, unsigned u)
{
ptr[0] = u;
ptr[1] = u >> 8;
ptr[2] = u >> 16;
ptr[3] = u >> 24;
}
static SNDFILE *sf_open_write(const char *path, SF_INFO *info)
{
int sub = info->format & SF_FORMAT_SUBMASK;
if (!(
(info->samplerate > 0) &&
(info->channels == 1 || info->channels == 2) &&
((info->format & SF_FORMAT_TYPEMASK) == SF_FORMAT_WAV) &&
(sub == SF_FORMAT_PCM_16 || sub == SF_FORMAT_PCM_U8 || sub == SF_FORMAT_FLOAT)
)) {
return NULL;
}
FILE *stream = fopen(path, "w+b");
unsigned char wav[58];
memset(wav, 0, sizeof(wav));
memcpy(wav, "RIFF", 4);
memcpy(&wav[8], "WAVEfmt ", 8);
if (sub == SF_FORMAT_FLOAT) {
wav[4] = 50; // riffSize
wav[16] = 18; // fmtSize
wav[20] = WAVE_FORMAT_IEEE_FLOAT;
} else {
wav[4] = 36; // riffSize
wav[16] = 16; // fmtSize
wav[20] = WAVE_FORMAT_PCM;
}
wav[22] = info->channels;
write4u(&wav[24], info->samplerate);
unsigned bitsPerSample;
switch (sub) {
case SF_FORMAT_PCM_16:
bitsPerSample = 16;
break;
case SF_FORMAT_PCM_U8:
bitsPerSample = 8;
break;
case SF_FORMAT_FLOAT:
bitsPerSample = 32;
break;
default: // not reachable
bitsPerSample = 0;
break;
}
unsigned blockAlignment = (bitsPerSample >> 3) * info->channels;
unsigned byteRate = info->samplerate * blockAlignment;
write4u(&wav[28], byteRate);
wav[32] = blockAlignment;
wav[34] = bitsPerSample;
if (sub == SF_FORMAT_FLOAT) {
memcpy(&wav[38], "fact", 4);
wav[42] = 4;
memcpy(&wav[50], "data", 4);
} else
memcpy(&wav[36], "data", 4);
// dataSize is initially zero
(void) fwrite(wav, sizeof(wav), 1, stream);
SNDFILE *handle = (SNDFILE *) malloc(sizeof(SNDFILE));
handle->mode = SFM_WRITE;
handle->temp = NULL;
handle->stream = stream;
handle->bytesPerFrame = blockAlignment;
handle->remaining = 0;
handle->info = *info;
return handle;
}
SNDFILE *sf_open(const char *path, int mode, SF_INFO *info)
{
if (path == NULL || info == NULL) {
fprintf(stderr, "path=%p info=%p\n", path, info);
return NULL;
}
switch (mode) {
case SFM_READ:
return sf_open_read(path, info);
case SFM_WRITE:
return sf_open_write(path, info);
default:
fprintf(stderr, "mode=%d\n", mode);
return NULL;
}
}
void sf_close(SNDFILE *handle)
{
if (handle == NULL)
return;
free(handle->temp);
if (handle->mode == SFM_WRITE) {
(void) fflush(handle->stream);
rewind(handle->stream);
unsigned char wav[58];
size_t extra = (handle->info.format & SF_FORMAT_SUBMASK) == SF_FORMAT_FLOAT ? 14 : 0;
(void) fread(wav, 44 + extra, 1, handle->stream);
unsigned dataSize = handle->remaining * handle->bytesPerFrame;
write4u(&wav[4], dataSize + 36 + extra); // riffSize
write4u(&wav[40 + extra], dataSize); // dataSize
rewind(handle->stream);
(void) fwrite(wav, 44 + extra, 1, handle->stream);
}
(void) fclose(handle->stream);
free(handle);
}
sf_count_t sf_readf_short(SNDFILE *handle, short *ptr, sf_count_t desiredFrames)
{
if (handle == NULL || handle->mode != SFM_READ || ptr == NULL || !handle->remaining ||
desiredFrames <= 0) {
return 0;
}
if (handle->remaining < (size_t) desiredFrames)
desiredFrames = handle->remaining;
// does not check for numeric overflow
size_t desiredBytes = desiredFrames * handle->bytesPerFrame;
size_t actualBytes;
void *temp = NULL;
unsigned format = handle->info.format & SF_FORMAT_SUBMASK;
if (format == SF_FORMAT_PCM_32 || format == SF_FORMAT_FLOAT) {
temp = malloc(desiredBytes);
actualBytes = fread(temp, sizeof(char), desiredBytes, handle->stream);
} else {
actualBytes = fread(ptr, sizeof(char), desiredBytes, handle->stream);
}
size_t actualFrames = actualBytes / handle->bytesPerFrame;
handle->remaining -= actualFrames;
switch (format) {
case SF_FORMAT_PCM_U8:
memcpy_to_i16_from_u8(ptr, (unsigned char *) ptr, actualFrames * handle->info.channels);
break;
case SF_FORMAT_PCM_16:
if (!isLittleEndian())
my_swab(ptr, actualFrames * handle->info.channels);
break;
case SF_FORMAT_PCM_32:
memcpy_to_i16_from_i32(ptr, (const int *) temp, actualFrames * handle->info.channels);
free(temp);
break;
case SF_FORMAT_FLOAT:
memcpy_to_i16_from_float(ptr, (const float *) temp, actualFrames * handle->info.channels);
free(temp);
break;
default:
memset(ptr, 0, actualFrames * handle->info.channels * sizeof(short));
break;
}
return actualFrames;
}
sf_count_t sf_readf_float(SNDFILE *handle, float *ptr, sf_count_t desiredFrames)
{
return 0;
}
sf_count_t sf_writef_short(SNDFILE *handle, const short *ptr, sf_count_t desiredFrames)
{
if (handle == NULL || handle->mode != SFM_WRITE || ptr == NULL || desiredFrames <= 0)
return 0;
size_t desiredBytes = desiredFrames * handle->bytesPerFrame;
size_t actualBytes = 0;
switch (handle->info.format & SF_FORMAT_SUBMASK) {
case SF_FORMAT_PCM_U8:
handle->temp = realloc(handle->temp, desiredBytes);
memcpy_to_u8_from_i16(handle->temp, ptr, desiredBytes);
actualBytes = fwrite(handle->temp, sizeof(char), desiredBytes, handle->stream);
break;
case SF_FORMAT_PCM_16:
// does not check for numeric overflow
if (isLittleEndian()) {
actualBytes = fwrite(ptr, sizeof(char), desiredBytes, handle->stream);
} else {
handle->temp = realloc(handle->temp, desiredBytes);
memcpy(handle->temp, ptr, desiredBytes);
my_swab((short *) handle->temp, desiredFrames * handle->info.channels);
actualBytes = fwrite(handle->temp, sizeof(char), desiredBytes, handle->stream);
}
break;
case SF_FORMAT_FLOAT: // transcoding from short to float not yet implemented
default:
break;
}
size_t actualFrames = actualBytes / handle->bytesPerFrame;
handle->remaining += actualFrames;
return actualFrames;
}
sf_count_t sf_writef_float(SNDFILE *handle, const float *ptr, sf_count_t desiredFrames)
{
if (handle == NULL || handle->mode != SFM_WRITE || ptr == NULL || desiredFrames <= 0)
return 0;
size_t desiredBytes = desiredFrames * handle->bytesPerFrame;
size_t actualBytes = 0;
switch (handle->info.format & SF_FORMAT_SUBMASK) {
case SF_FORMAT_FLOAT:
actualBytes = fwrite(ptr, sizeof(char), desiredBytes, handle->stream);
break;
case SF_FORMAT_PCM_U8: // transcoding from float to byte/short not yet implemented
case SF_FORMAT_PCM_16:
default:
break;
}
size_t actualFrames = actualBytes / handle->bytesPerFrame;
handle->remaining += actualFrames;
return actualFrames;
}