Missing unlink / Bug on 0 byte files?

Hi,

I'm using Build r1000.
It seems to me, that the MAfs Library is missing unlink() to delete a file.
Additionally, fflush() is referenced in the .h file but not implemented, as it seems (at least a stub that returns 0 would be desirable).

So I implemented by own version of unlink, which basically just truncates the file (any better ideas?):
// MoSync doesn't have unlink, so we truncate the file by opening it.

int unlink(const char *pszFile)
{
	FILE *fp = fopen(pszFile, "w");
	if (fp)
	{
		fclose(fp);
		return 0;
	}
	return 1;
}

Now it seems to me that the FS library has a bug on handling 0 byte files and gets stuck on fwrite.
Here are my assumptions about the things happening:

File.c:

static MA_FILE* openReadWrite(const char *filename, int modeFlags) {
...
        if(modeFlags&(MODE_READ|MODE_APPEND)) {
                data = maCreatePlaceholder();
                maReadStore(store, data);
                realLength = size = maGetDataSize(data);    // size = 0 on 0 byte files?
        }
...
        file->bufferStart = 0;
        file->bufferSize = size;
}

Now on fwrite:

size_t MA_fwrite ( const void * ptr, size_t size, size_t count, MA_FILE * stream) {
...
                int lastBufferSize = stream->bufferSize;
                while(stream->filePtr+bytesToWrite >  vol->dataOffset+stream->bufferSize) stream->bufferSize<<=1;
...
}

0<<1 = 0<<1 = 0<<1 = 0<<1 = 0...

Seems buggy to me. Is this a real bug or are my assumptions wrong? Nevertheless, it hangs here in fwrite and loops forever.

Regards,
Ludwig