int ZEXPORT deflateParams()

in zlib/deflate.c [752:794]

• 39 lines of code
• 16 McCabe index (conditional complexity)

int ZEXPORT deflateParams(z_streamp strm, int level, int strategy) {
    deflate_state *s;
    compress_func func;

    if (deflateStateCheck(strm)) return Z_STREAM_ERROR;
    s = strm->state;

#ifdef FASTEST
    if (level != 0) level = 1;
#else
    if (level == Z_DEFAULT_COMPRESSION) level = 6;
#endif
    if (level < 0 || level > 9 || strategy < 0 || strategy > Z_FIXED) {
        return Z_STREAM_ERROR;
    }
    func = configuration_table[s->level].func;

    if ((strategy != s->strategy || func != configuration_table[level].func) &&
        s->last_flush != -2) {
        /* Flush the last buffer: */
        int err = deflate(strm, Z_BLOCK);
        if (err == Z_STREAM_ERROR)
            return err;
        if (strm->avail_in || (s->strstart - s->block_start) + s->lookahead)
            return Z_BUF_ERROR;
    }
    if (s->level != level) {
        if (s->level == 0 && s->matches != 0) {
            if (s->matches == 1)
                slide_hash(s);
            else
                CLEAR_HASH(s);
            s->matches = 0;
        }
        s->level = level;
        s->max_lazy_match   = configuration_table[level].max_lazy;
        s->good_match       = configuration_table[level].good_length;
        s->nice_match       = configuration_table[level].nice_length;
        s->max_chain_length = configuration_table[level].max_chain;
    }
    s->strategy = strategy;
    return Z_OK;
}