static SNDFILE *sf_open_read(const char *path, SF_INFO *info)
{
FILE *stream = fopen(path, "rb");
if (stream == NULL)
return NULL;
// don't attempt to parse all valid forms, just the most common one
unsigned char wav[44];
size_t actual;
actual = fread(wav, sizeof(char), sizeof(wav), stream);
if (actual != sizeof(wav))
return NULL;
for (;;) {
if (memcmp(wav, "RIFF", 4))
break;
unsigned riffSize = little4u(&wav[4]);
if (riffSize < 36)
break;
if (memcmp(&wav[8], "WAVEfmt ", 8))
break;
unsigned fmtsize = little4u(&wav[16]);
if (fmtsize != 16)
break;
unsigned format = little2u(&wav[20]);
if (format != 1) // PCM
break;
unsigned channels = little2u(&wav[22]);
if (channels != 1 && channels != 2)
break;
unsigned samplerate = little4u(&wav[24]);
if (samplerate == 0)
break;
// ignore byte rate
// ignore block alignment
unsigned bitsPerSample = little2u(&wav[34]);
if (bitsPerSample != 8 && bitsPerSample != 16)
break;
unsigned bytesPerFrame = (bitsPerSample >> 3) * channels;
if (memcmp(&wav[36], "data", 4))
break;
unsigned dataSize = little4u(&wav[40]);
SNDFILE *handle = (SNDFILE *) malloc(sizeof(SNDFILE));
handle->mode = SFM_READ;
handle->temp = NULL;
handle->stream = stream;
handle->bytesPerFrame = bytesPerFrame;
handle->remaining = dataSize / bytesPerFrame;
handle->info.frames = handle->remaining;
handle->info.samplerate = samplerate;
handle->info.channels = channels;
handle->info.format = SF_FORMAT_WAV;
if (bitsPerSample == 8)
handle->info.format |= SF_FORMAT_PCM_U8;
else
handle->info.format |= SF_FORMAT_PCM_16;
*info = handle->info;
return handle;
}
return NULL;
}
// "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) {
#ifdef HAVE_STDERR
fprintf(stderr, "fopen %s failed errno %d\n", path, errno);
#endif
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) {
#ifdef HAVE_STDERR
fprintf(stderr, "actual %zu < 44\n", actual);
#endif
goto close;
}
if (memcmp(wav, "RIFF", 4)) {
#ifdef HAVE_STDERR
fprintf(stderr, "wav != RIFF\n");
#endif
goto close;
}
unsigned riffSize = little4u(&wav[4]);
if (riffSize < 4) {
#ifdef HAVE_STDERR
fprintf(stderr, "riffSize %u < 4\n", riffSize);
#endif
goto close;
}
if (memcmp(&wav[8], "WAVE", 4)) {
#ifdef HAVE_STDERR
fprintf(stderr, "missing WAVE\n");
#endif
goto close;
}
size_t remaining = riffSize - 4;
int hadFmt = 0;
int hadData = 0;
long dataTell = 0L;
while (remaining >= 8) {
unsigned char chunk[8];
actual = fread(chunk, sizeof(char), sizeof(chunk), stream);
if (actual != sizeof(chunk)) {
#ifdef HAVE_STDERR
fprintf(stderr, "actual %zu != %zu\n", actual, sizeof(chunk));
#endif
goto close;
}
remaining -= 8;
unsigned chunkSize = little4u(&chunk[4]);
if (chunkSize > remaining) {
#ifdef HAVE_STDERR
fprintf(stderr, "chunkSize %u > remaining %zu\n", chunkSize, remaining);
#endif
goto close;
}
if (!memcmp(&chunk[0], "fmt ", 4)) {
if (hadFmt) {
#ifdef HAVE_STDERR
fprintf(stderr, "multiple fmt\n");
#endif
goto close;
}
if (chunkSize < 2) {
#ifdef HAVE_STDERR
fprintf(stderr, "chunkSize %u < 2\n", chunkSize);
#endif
goto close;
}
unsigned char fmt[40];
actual = fread(fmt, sizeof(char), 2, stream);
if (actual != 2) {
#ifdef HAVE_STDERR
fprintf(stderr, "actual %zu != 2\n", actual);
#endif
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:
#ifdef HAVE_STDERR
fprintf(stderr, "unsupported format %u\n", format);
#endif
goto close;
}
if (chunkSize < minSize) {
#ifdef HAVE_STDERR
fprintf(stderr, "chunkSize %u < minSize %zu\n", chunkSize, minSize);
#endif
goto close;
}
actual = fread(&fmt[2], sizeof(char), minSize - 2, stream);
if (actual != minSize - 2) {
#ifdef HAVE_STDERR
fprintf(stderr, "actual %zu != %zu\n", actual, minSize - 16);
#endif
goto close;
}
if (chunkSize > minSize) {
fseek(stream, (long) (chunkSize - minSize), SEEK_CUR);
}
unsigned channels = little2u(&fmt[2]);
if ((channels < 1) || (channels > FCC_8)) {
#ifdef HAVE_STDERR
fprintf(stderr, "unsupported channels %u\n", channels);
#endif
goto close;
}
unsigned samplerate = little4u(&fmt[4]);
if (samplerate == 0) {
#ifdef HAVE_STDERR
fprintf(stderr, "samplerate %u == 0\n", samplerate);
#endif
goto close;
}
// ignore byte rate
// ignore block alignment
unsigned bitsPerSample = little2u(&fmt[14]);
if (bitsPerSample != 8 && bitsPerSample != 16 && bitsPerSample != 24 &&
bitsPerSample != 32) {
#ifdef HAVE_STDERR
fprintf(stderr, "bitsPerSample %u != 8 or 16 or 24 or 32\n", bitsPerSample);
#endif
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 24:
handle->info.format |= SF_FORMAT_PCM_24;
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) {
#ifdef HAVE_STDERR
fprintf(stderr, "data not preceded by fmt\n");
#endif
goto close;
}
if (hadData) {
#ifdef HAVE_STDERR
fprintf(stderr, "multiple data\n");
#endif
goto close;
}
handle->remaining = chunkSize / handle->bytesPerFrame;
handle->info.frames = handle->remaining;
dataTell = ftell(stream);
if (chunkSize > 0) {
fseek(stream, (long) chunkSize, SEEK_CUR);
}
hadData = 1;
} else if (!memcmp(&chunk[0], "fact", 4)) {
// ignore fact
if (chunkSize > 0) {
fseek(stream, (long) chunkSize, SEEK_CUR);
}
} else {
// ignore unknown chunk
#ifdef HAVE_STDERR
fprintf(stderr, "ignoring unknown chunk %c%c%c%c\n",
chunk[0], chunk[1], chunk[2], chunk[3]);
#endif
if (chunkSize > 0) {
fseek(stream, (long) chunkSize, SEEK_CUR);
}
}
remaining -= chunkSize;
}