Method initPrefix

Vanity.cpp:338–526

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// ----------------------------------------------------------------------------
bool VanitySearch::initPrefix(std::string &prefix,PREFIX_ITEM *it) {

  std::vector<unsigned char> result;
  string dummy1 = prefix;
  int nbDigit = 0;
  bool wrong = false;

  if (prefix.length() < 2) {
    printf("Ignoring prefix \"%s\" (too short)\n",prefix.c_str());
    return false;
  }

  int aType = -1;


  switch (prefix.data()[0]) {
  case '1':
    aType = P2PKH;
    break;
  case '3':
    aType = P2SH;
    break;
  case 'b':
  case 'B':
    std::transform(prefix.begin(), prefix.end(), prefix.begin(), ::tolower);
    if(strncmp(prefix.c_str(), "bc1q", 4) == 0)
      aType = BECH32;
    break;
  }

  if (aType==-1) {
    printf("Ignoring prefix \"%s\" (must start with 1 or 3 or bc1q)\n", prefix.c_str());
    return false;
  }

  if (searchType == -1) searchType = aType;
  if (aType != searchType) {
    printf("Ignoring prefix \"%s\" (P2PKH, P2SH or BECH32 allowed at once)\n", prefix.c_str());
    return false;
  }

  if (aType == BECH32) {

    // BECH32
    uint8_t witprog[40];
    size_t witprog_len;
    int witver;
    const char* hrp = "bc";

    int ret = segwit_addr_decode(&witver, witprog, &witprog_len, hrp, prefix.c_str());

    // Try to attack a full address ?
    if (ret && witprog_len==20) {

      // mamma mia !
      it->difficulty = pow(2, 160);
      it->isFull = true;
      memcpy(it->hash160, witprog, 20);