Function getexCommand

src/t_string.cpp:331–405

* GETEX [PERSIST][EX seconds][PX milliseconds][EXAT seconds-timestamp][PXAT milliseconds-timestamp] * * The getexCommand() function implements extended options and variants of the GET command. Unlike GET * command this command is not read-only. * * The default behavior when no options are specified is same as GET and does not alter any TTL. * * Only one of the below options can be use

 * Command would either return the bulk string, error or nil.
 */
void getexCommand(client *c) {
    robj *expire = NULL;
    int unit = UNIT_SECONDS;
    int flags = OBJ_NO_FLAGS;

    if (parseExtendedStringArgumentsOrReply(c,&flags,&unit,&expire,COMMAND_GET) != C_OK) {
        return;
    }

    robj_roptr o;

    if ((o = lookupKeyReadOrReply(c,c->argv[1],shared.null[c->resp])) == nullptr)
        return;

    if (checkType(c,o,OBJ_STRING)) {
        return;
    }

    long long milliseconds = 0, when = 0;

    /* Validate the expiration time value first */
    if (expire) {
        if (getLongLongFromObjectOrReply(c, expire, &milliseconds, NULL) != C_OK)
            return;
        if (milliseconds <= 0 || (unit == UNIT_SECONDS && milliseconds > LLONG_MAX / 1000)) {
            /* Negative value provided or multiplication is gonna overflow. */
            addReplyErrorFormat(c, "invalid expire time in %s", c->cmd->name);
            return;
        }
        if (unit == UNIT_SECONDS) milliseconds *= 1000;
        when = milliseconds;
        if ((flags & OBJ_PX) || (flags & OBJ_EX))
            when += mstime();
        if (when <= 0) {
            /* Overflow detected. */
            addReplyErrorFormat(c, "invalid expire time in %s", c->cmd->name);
            return;
        }
    }

    /* We need to do this before we expire the key or delete it */
    addReplyBulk(c,o);

    /* This command is never propagated as is. It is either propagated as PEXPIRE[AT],DEL,UNLINK or PERSIST.
     * This why it doesn't need special handling in feedAppendOnlyFile to convert relative expire time to absolute one. */
    if (((flags & OBJ_PXAT) || (flags & OBJ_EXAT)) && checkAlreadyExpired(milliseconds)) {
        /* When PXAT/EXAT absolute timestamp is specified, there can be a chance that timestamp
         * has already elapsed so delete the key in that case. */
        int deleted = g_pserver->lazyfree_lazy_expire ? dbAsyncDelete(c->db, c->argv[1]) :
                      dbSyncDelete(c->db, c->argv[1]);
        serverAssert(deleted);
        robj *aux = g_pserver->lazyfree_lazy_expire ? shared.unlink : shared.del;
        rewriteClientCommandVector(c,2,aux,c->argv[1]);
        signalModifiedKey(c, c->db, c->argv[1]);
        notifyKeyspaceEvent(NOTIFY_GENERIC, "del", c->argv[1], c->db->id);
        g_pserver->dirty++;
    } else if (expire) {
        setExpire(c,c->db,c->argv[1],nullptr,when);