Function MatchLiquidWatchman

src/pegins.cpp:389–459

}

bool MatchLiquidWatchman(const CScript& script)
{
    CScript::const_iterator it = script.begin();
    std::vector<unsigned char> data;
    opcodetype opcode;

    // Stack depth check for branch choice
    if (!script.GetOp(it, opcode, data) || opcode != OP_DEPTH) {
        return false;
    }
    // Take in value, then check equality
    if (!script.GetOp(it, opcode, data) ||
            !script.GetOp(it, opcode, data) ||
            opcode != OP_EQUAL) {
        return false;
    }
    // IF EQUAL
    if (!script.GetOp(it, opcode, data) || opcode != OP_IF) {
        return false;
    }
    // Take in value k, make sure minimally encoded number from 1 to 16
    if (!script.GetOp(it, opcode, data) ||
            opcode > OP_16 ||
            (opcode < OP_1NEGATE && !CheckMinimalPush(data, opcode))) {
        return false;
    }
    opcodetype opcode2 = opcode;
    std::vector<unsigned char> num = data;
    // Iterate through multisig stuff until ELSE is hit
    while (opcode != OP_ELSE) {
        if (!script.GetOp(it, opcode, data)) {
            return false;
        }
    }
    // Take minimally-encoded CSV push number k'
    if (!script.GetOp(it, opcode, data) ||
            opcode > OP_16 || (opcode < OP_1NEGATE && !CheckMinimalPush(data, opcode))) {
        return false;
    }
    // CSV
    if (!script.GetOp(it, opcode, data) || opcode != OP_CHECKSEQUENCEVERIFY) {
        return false;
    }
    // Drop the CSV number
    if (!script.GetOp(it, opcode, data) || opcode != OP_DROP) {
        return false;
    }
    // Take the minimally-encoded n of k-of-n multisig arg
    if (!script.GetOp(it, opcode, data) ||
            opcode > OP_16 || (opcode < OP_1NEGATE && !CheckMinimalPush(data, opcode)) ) {
        return false;
    }

    // The two multisig k-numbers must not match, otherwise ELSE branch can not be reached
    if (opcode == opcode2 && num == data) {
        return false;
    }