Method writeData

Fleece/Core/Encoder.cc:320–344

Subroutine for writing strings or binary data. Returns the address of the string in the output (not the Value; the raw string itself), which can be used until the enoding is over. (Unless the string is written inline, or directly to file, in which case NULL is returned.)

    // output (not the Value; the raw string itself), which can be used until the enoding is over.
    // (Unless the string is written inline, or directly to file, in which case NULL is returned.)
    const void* Encoder::writeData(tags tag, slice s) {
        byte *buf;
        if (s.size < kNarrow) {
            // Tiny data (0 or 1 byte) fits inline:
            buf = placeValue<true>(tag, byte(s.size), 1 + s.size);
            buf[1] = s.size > 0 ? s[0] : 0;
            buf = nullptr; // this string is ephemeral
        } else {
            // Large data doesn't:
            size_t bufLen = 1 + s.size;
            if (s.size >= 0x0F)
                bufLen += SizeOfVarInt(s.size);
            buf = placeValue<false>(tag, 0, bufLen);
            if (s.size < 0x0F) {
                *buf++ |= byte(s.size);
            } else {
                *buf++ |= 0x0F;
                buf += PutUVarInt(buf, s.size);
            }
            memcpy(buf, s.buf, s.size);
            if (_out.outputFile())
                buf = nullptr;          // ephemeral if writing to file
        }
        return buf;
    }

    // Writes a string, or a pointer to an already-written copy of the same string.
    // This is the main body of writeString() and writeKey().