Function ldbRedis

app/redis-6.2.6/src/scripting.c:2592–2617

Implement the debugger "redis" command. We use a trick in order to make * the implementation very simple: we just call the Lua redis.call() command * implementation, with ldb.step enabled, so as a side effect the Redis command * and its reply are logged. */

 * implementation, with ldb.step enabled, so as a side effect the Redis command
 * and its reply are logged. */
void ldbRedis(lua_State *lua, sds *argv, int argc) {
    int j, saved_rc = server.lua_replicate_commands;

    if (!lua_checkstack(lua, argc + 1)) {
        /* Increase the Lua stack if needed to make sure there is enough room
         * to push 'argc + 1' elements to the stack. On failure, return error.
         * Notice that we need, in worst case, 'argc + 1' elements because we push all the arguments
         * given by the user (without the first argument) and we also push the 'redis' global table and
         * 'redis.call' function so:
         * (1 (redis table)) + (1 (redis.call function)) + (argc - 1 (all arguments without the first)) = argc + 1*/
        ldbLogRedisReply("max lua stack reached");
        return;
    }

    lua_getglobal(lua,"redis");
    lua_pushstring(lua,"call");
    lua_gettable(lua,-2);       /* Stack: redis, redis.call */
    for (j = 1; j < argc; j++)
        lua_pushlstring(lua,argv[j],sdslen(argv[j]));
    ldb.step = 1;               /* Force redis.call() to log. */
    server.lua_replicate_commands = 1;
    lua_pcall(lua,argc-1,1,0);  /* Stack: redis, result */
    ldb.step = 0;               /* Disable logging. */
    server.lua_replicate_commands = saved_rc;
    lua_pop(lua,2);             /* Discard the result and clean the stack. */
}

/* Implements "trace" command of the Lua debugger. It just prints a backtrace
 * querying Lua starting from the current callframe back to the outer one. */