void hincrbyCommand(client *c) {
    long long value, incr, oldvalue;
    robj *o;
    sds new;
    unsigned char *vstr;
    unsigned int vlen;

    if (getLongLongFromObjectOrReply(c,c->argv[3],&incr,NULL) != C_OK) return;
    if ((o = hashTypeLookupWriteOrCreate(c,c->argv[1])) == NULL) return;
    if (hashTypeGetValue(o,c->argv[2]->ptr,&vstr,&vlen,&value) == C_OK) {
        if (vstr) {
            if (string2ll((char*)vstr,vlen,&value) == 0) {
                addReplyError(c,"hash value is not an integer");
                return;
            }
        } /* Else hashTypeGetValue() already stored it into &value */
    } else {
        value = 0;
    }

    oldvalue = value;
    if ((incr < 0 && oldvalue < 0 && incr < (LLONG_MIN-oldvalue)) ||
        (incr > 0 && oldvalue > 0 && incr > (LLONG_MAX-oldvalue))) {
        addReplyError(c,"increment or decrement would overflow");
        return;
    }
    value += incr;
    new = sdsfromlonglong(value);
    hashTypeSet(o,c->argv[2]->ptr,new,HASH_SET_TAKE_VALUE);
    addReplyLongLong(c,value);
    signalModifiedKey(c,c->db,c->argv[1]);
    notifyKeyspaceEvent(NOTIFY_HASH,"hincrby",c->argv[1],c->db->id);
    server.dirty++;
}
void hincrbyCommand(client *c) {
    long long value, incr, oldvalue;
    robj *o;
    sds new;
    unsigned char *vstr;
    unsigned int vlen;

    if (getLongLongFromObjectOrReply(c,c->argv[3],&incr,NULL) != C_OK) return;
    if ((o = hashTypeLookupWriteOrCreate(c,c->argv[1])) == NULL) return;
    if (hashTypeGetValue(o,c->argv[2]->ptr,&vstr,&vlen,&value) == C_OK) {
        if (vstr) {
            if (string2ll((char*)vstr,vlen,&value) == 0) {
                addReplyError(c,"hash value is not an integer");
                return;
            }
        }  
    } else {
        value = 0;
    }

    oldvalue = value;
    if ((incr < 0 && oldvalue < 0 && incr < (LLONG_MIN-oldvalue)) ||
        (incr > 0 && oldvalue > 0 && incr > (LLONG_MAX-oldvalue))) {
        addReplyError(c,"increment or decrement would overflow");
        return;
    }
    value += incr;
    new = sdsfromlonglong(value);
    hashTypeSet(o,c->argv[2]->ptr,new,HASH_SET_TAKE_VALUE);
    addReplyLongLong(c,value);
    signalModifiedKey(c,c->db,c->argv[1]);
    notifyKeyspaceEvent(NOTIFY_HASH,"hincrby",c->argv[1],c->db->id);
    server.dirty++;
}