Function luaPushError

app/redis-6.2.6/src/scripting.c:286–308

This function is used in order to push an error on the Lua stack in the * format used by redis.pcall to return errors, which is a lua table * with a single "err" field set to the error string. Note that this * table is never a valid reply by proper commands, since the returned * tables are otherwise always indexed by integers, never by strings. */

 * table is never a valid reply by proper commands, since the returned
 * tables are otherwise always indexed by integers, never by strings. */
void luaPushError(lua_State *lua, char *error) {
    lua_Debug dbg;

    /* If debugging is active and in step mode, log errors resulting from
     * Redis commands. */
    if (ldb.active && ldb.step) {
        ldbLog(sdscatprintf(sdsempty(),"<error> %s",error));
    }

    lua_newtable(lua);
    lua_pushstring(lua,"err");

    /* Attempt to figure out where this function was called, if possible */
    if(lua_getstack(lua, 1, &dbg) && lua_getinfo(lua, "nSl", &dbg)) {
        sds msg = sdscatprintf(sdsempty(), "%s: %d: %s",
            dbg.source, dbg.currentline, error);
        lua_pushstring(lua, msg);
        sdsfree(msg);
    } else {
        lua_pushstring(lua, error);
    }
    lua_settable(lua,-3);
}

/* In case the error set into the Lua stack by luaPushError() was generated
 * by the non-error-trapping version of redis.pcall(), which is redis.call(),