void FindChunk(char *name)
{
last_chunk = iff_data;
FindNextChunk (name);
}
/*
============
GetWavinfo
============
*/
wavinfo_t GetWavinfo (char *name, byte *wav, int wavlength)
{
wavinfo_t info;
int i;
int format;
int samples;
memset (&info, 0, sizeof(info));
if (!wav)
return info;
iff_data = wav;
iff_end = wav + wavlength;
// find "RIFF" chunk
FindChunk("RIFF");
if (!(data_p && !strncmp((char *)data_p+8, "WAVE", 4)))
{
Com_Printf("Missing RIFF/WAVE chunks\n");
return info;
}
// get "fmt " chunk
iff_data = data_p + 12;
// DumpChunks ();
FindChunk("fmt ");
if (!data_p)
{
Com_Printf("Missing fmt chunk\n");
return info;
}
data_p += 8;
format = GetLittleShort();
if (format != 1)
{
Com_Printf("Microsoft PCM format only\n");
return info;
}
info.channels = GetLittleShort();
info.rate = GetLittleLong();
data_p += 4+2;
info.width = GetLittleShort() / 8;
// get cue chunk
FindChunk("cue ");
if (data_p)
{
data_p += 32;
info.loopstart = GetLittleLong();
// Com_Printf("loopstart=%d\n", sfx->loopstart);
// if the next chunk is a LIST chunk, look for a cue length marker
FindNextChunk ("LIST");
if (data_p)
{
if (!strncmp ((char *)data_p + 28, "mark", 4))
{ // this is not a proper parse, but it works with cooledit...
data_p += 24;
i = GetLittleLong (); // samples in loop
info.samples = info.loopstart + i;
// Com_Printf("looped length: %i\n", i);
}
}
}
else
info.loopstart = -1;
// find data chunk
FindChunk("data");
if (!data_p)
{
Com_Printf("Missing data chunk\n");
return info;
}
data_p += 4;
samples = GetLittleLong () / info.width;
if (info.samples)
{
if (samples < info.samples)
Com_Error (ERR_DROP, "Sound %s has a bad loop length", name);
}
else
info.samples = samples;
info.dataofs = data_p - wav;
return info;
}
static void
FindChunk(const char *name, const char *filename)
{
last_chunk = iff_data;
FindNextChunk(name, filename);
}
