void Buffer::SetPos(int value) { if ((value >= fileLen) && (stream != NULL) && !CanSeek()) { // Wanted position is after buffer and the stream // is not seek-able e.g. network or console, // thus we have to read the stream manually till // the wanted position is in sight. while ((value >= fileLen) && (ReadNextStreamChunk() > 0)); } if ((value < 0) || (value > fileLen)) { wprintf(L"--- buffer out of bounds access, position: %d\n", value); MX_DEBUG_BREAK; exit(1); } if ((value >= bufStart) && (value < (bufStart + bufLen))) { // already in buffer bufPos = value - bufStart; } else if (stream != NULL) { // must be swapped in fseek(stream, value, SEEK_SET); bufLen = fread(buf, sizeof(unsigned char), bufCapacity, stream); bufStart = value; bufPos = 0; } else { bufPos = fileLen - bufStart; // make Pos return fileLen } }
int Buffer::Read() { if (bufPos < bufLen) { return buf[bufPos++]; } else if (GetPos() < fileLen) { SetPos(GetPos()); // shift buffer start to Pos return buf[bufPos++]; } else if ((stream != NULL) && !CanSeek() && (ReadNextStreamChunk() > 0)) { return buf[bufPos++]; } else { return EoF; } }