findDCTDecodeInlineStreamEnd()

in src/core/parser.js [327:423]
80 lines of code
47 McCabe index (conditional complexity)

  findDCTDecodeInlineStreamEnd(stream) {
    const startPos = stream.pos;
    let foundEOI = false,
      b,
      markerLength;
    while ((b = stream.getByte()) !== -1) {
      if (b !== 0xff) {
        // Not a valid marker.
        continue;
      }
      switch (stream.getByte()) {
        case 0x00: // Byte stuffing.
          // 0xFF00 appears to be a very common byte sequence in JPEG images.
          break;

        case 0xff: // Fill byte.
          // Avoid skipping a valid marker, resetting the stream position.
          stream.skip(-1);
          break;

        case 0xd9: // EOI
          foundEOI = true;
          break;

        case 0xc0: // SOF0
        case 0xc1: // SOF1
        case 0xc2: // SOF2
        case 0xc3: // SOF3
        /* falls through */
        case 0xc5: // SOF5
        case 0xc6: // SOF6
        case 0xc7: // SOF7
        /* falls through */
        case 0xc9: // SOF9
        case 0xca: // SOF10
        case 0xcb: // SOF11
        /* falls through */
        case 0xcd: // SOF13
        case 0xce: // SOF14
        case 0xcf: // SOF15
        /* falls through */
        case 0xc4: // DHT
        case 0xcc: // DAC
        /* falls through */
        case 0xda: // SOS
        case 0xdb: // DQT
        case 0xdc: // DNL
        case 0xdd: // DRI
        case 0xde: // DHP
        case 0xdf: // EXP
        /* falls through */
        case 0xe0: // APP0
        case 0xe1: // APP1
        case 0xe2: // APP2
        case 0xe3: // APP3
        case 0xe4: // APP4
        case 0xe5: // APP5
        case 0xe6: // APP6
        case 0xe7: // APP7
        case 0xe8: // APP8
        case 0xe9: // APP9
        case 0xea: // APP10
        case 0xeb: // APP11
        case 0xec: // APP12
        case 0xed: // APP13
        case 0xee: // APP14
        case 0xef: // APP15
        /* falls through */
        case 0xfe: // COM
          // The marker should be followed by the length of the segment.
          markerLength = stream.getUint16();
          if (markerLength > 2) {
            // |markerLength| contains the byte length of the marker segment,
            // including its own length (2 bytes) and excluding the marker.
            stream.skip(markerLength - 2); // Jump to the next marker.
          } else {
            // The marker length is invalid, resetting the stream position.
            stream.skip(-2);
          }
          break;
      }
      if (foundEOI) {
        break;
      }
    }
    const length = stream.pos - startPos;
    if (b === -1) {
      warn(
        "Inline DCTDecode image stream: " +
          "EOI marker not found, searching for /EI/ instead."
      );
      stream.skip(-length); // Reset the stream position.
      return this.findDefaultInlineStreamEnd(stream);
    }
    this.inlineStreamSkipEI(stream);
    return length;
  }