Method Unserialize

src/psbt.h:1686–1997

    template <typename Stream>
    inline void Unserialize(Stream& s) {
        // Read the magic bytes
        uint8_t magic[5];
        s >> magic;
        if (!std::equal(magic, magic + 5, PSBT_ELEMENTS_MAGIC_BYTES)) {
            throw std::ios_base::failure("Invalid PSBT magic bytes");
        }

        // Used for duplicate key detection
        std::set<std::vector<unsigned char>> key_lookup;

        // Track the global xpubs we have already seen. Just for sanity checking
        std::set<CExtPubKey> global_xpubs;

        // Read global data
        bool found_sep = false;
        uint64_t input_count = 0;
        uint64_t output_count = 0;
        bool found_input_count = false;
        bool found_output_count = false;
        while(!s.empty()) {
            // Read
            std::vector<unsigned char> key;
            s >> key;

            // the key is empty if that was actually a separator byte
            // This is a special case for key lengths 0 as those are not allowed (except for separator)
            if (key.empty()) {
                found_sep = true;
                break;
            }

            // Type is compact size uint at beginning of key
            SpanReader skey(s.GetType(), s.GetVersion(), key);
            uint64_t type = ReadCompactSize(skey);

            // Do stuff based on type
            switch(type) {
                case PSBT_GLOBAL_UNSIGNED_TX:
                {
                    if (g_con_elementsmode) {
                        throw std::ios_base::failure("Unsigned tx is not allowed in PSET");
                    }
                    if (!key_lookup.emplace(key).second) {
                        throw std::ios_base::failure("Duplicate Key, unsigned tx already provided");
                    } else if (key.size() != 1) {
                        throw std::ios_base::failure("Global unsigned tx key is more than one byte type");
                    }
                    CMutableTransaction mtx;
                    // Set the stream to serialize with non-witness since this should always be non-witness
                    OverrideStream<Stream> os(&s, s.GetType(), s.GetVersion() | SERIALIZE_TRANSACTION_NO_WITNESS);
                    UnserializeFromVector(os, mtx);
                    tx = std::move(mtx);
                    // Make sure that all scriptSigs and scriptWitnesses are empty
                    for (unsigned int i = 0; i < tx->vin.size(); i++) {
                        const CTxIn& txin = tx->vin[i];
                        if (!txin.scriptSig.empty() || !tx->witness.vtxinwit[i].scriptWitness.IsNull()) {
                            throw std::ios_base::failure("Unsigned tx does not have empty scriptSigs and scriptWitnesses.");