static int
set_pos_rel_callback(void *id, int32_t delta, int mode)
{
assert(nullptr != id);
WavPackDecoder *decoder = static_cast<WavPackDecoder *>(id);
InputSource *inputSource = decoder->GetInputSource();
if(!inputSource->SupportsSeeking())
return -1;
// Adjust offset as required
SInt64 offset = delta;
switch(mode) {
case SEEK_SET:
// offset remains unchanged
break;
case SEEK_CUR:
offset += inputSource->GetOffset();
break;
case SEEK_END:
offset += inputSource->GetLength();
break;
}
return (!inputSource->SeekToOffset(offset));
}
// FIXME: How does one emulate ungetc when the data is non-seekable?
static int
push_back_byte_callback(void *id, int c)
{
assert(nullptr != id);
WavPackDecoder *decoder = static_cast<WavPackDecoder *>(id);
InputSource *inputSource = decoder->GetInputSource();
if(!inputSource->SupportsSeeking())
return EOF;
if(!inputSource->SeekToOffset(inputSource->GetOffset() - 1))
return EOF;
return c;
}
