Function evalGenericCommand

app/redis-6.2.6/src/scripting.c:1514–1720

}

void evalGenericCommand(client *c, int evalsha) {
    lua_State *lua = server.lua;
    char funcname[43];
    long long numkeys;
    long long initial_server_dirty = server.dirty;
    int delhook = 0, err;

    /* When we replicate whole scripts, we want the same PRNG sequence at
     * every call so that our PRNG is not affected by external state. */
    redisSrand48(0);

    /* We set this flag to zero to remember that so far no random command
     * was called. This way we can allow the user to call commands like
     * SRANDMEMBER or RANDOMKEY from Lua scripts as far as no write command
     * is called (otherwise the replication and AOF would end with non
     * deterministic sequences).
     *
     * Thanks to this flag we'll raise an error every time a write command
     * is called after a random command was used. */
    server.lua_random_dirty = 0;
    server.lua_write_dirty = 0;
    server.lua_replicate_commands = server.lua_always_replicate_commands;
    server.lua_multi_emitted = 0;
    server.lua_repl = PROPAGATE_AOF|PROPAGATE_REPL;

    /* Get the number of arguments that are keys */
    if (getLongLongFromObjectOrReply(c,c->argv[2],&numkeys,NULL) != C_OK)
        return;
    if (numkeys > (c->argc - 3)) {
        addReplyError(c,"Number of keys can't be greater than number of args");
        return;
    } else if (numkeys < 0) {
        addReplyError(c,"Number of keys can't be negative");
        return;
    }

    /* We obtain the script SHA1, then check if this function is already
     * defined into the Lua state */
    funcname[0] = 'f';
    funcname[1] = '_';
    if (!evalsha) {
        /* Hash the code if this is an EVAL call */
        sha1hex(funcname+2,c->argv[1]->ptr,sdslen(c->argv[1]->ptr));
    } else {
        /* We already have the SHA if it is an EVALSHA */
        int j;
        char *sha = c->argv[1]->ptr;

        /* Convert to lowercase. We don't use tolower since the function
         * managed to always show up in the profiler output consuming
         * a non trivial amount of time. */
        for (j = 0; j < 40; j++)
            funcname[j+2] = (sha[j] >= 'A' && sha[j] <= 'Z') ?
                sha[j]+('a'-'A') : sha[j];
        funcname[42] = '\0';
    }

    /* Push the pcall error handler function on the stack. */