int SSDBImpl::_qpop(const Bytes &name, std::string *item, uint64_t front_or_back_seq, char log_type){
Transaction trans(binlogs);
int ret;
uint64_t seq;
ret = qget_uint64(this->ldb, name, front_or_back_seq, &seq);
if(ret == -1){
return -1;
}
if(ret == 0){
return 0;
}
ret = qget_by_seq(this->ldb, name, seq, item);
if(ret == -1){
return -1;
}
if(ret == 0){
return 0;
}
// delete item
ret = qdel_one(this, name, seq);
if(ret == -1){
return -1;
}
if(front_or_back_seq == QFRONT_SEQ){
binlogs->add_log(log_type, BinlogCommand::QPOP_FRONT, name.String());
}else{
binlogs->add_log(log_type, BinlogCommand::QPOP_BACK, name.String());
}
// update size
int64_t size = incr_qsize(this, name, -1);
if(size == -1){
return -1;
}
// update front
if(size > 0){
seq += (front_or_back_seq == QFRONT_SEQ)? +1 : -1;
//log_debug("seq: %" PRIu64 ", ret: %d", seq, ret);
ret = qset_one(this, name, front_or_back_seq, Bytes(&seq, sizeof(seq)));
if(ret == -1){
return -1;
}
}
leveldb::Status s = binlogs->commit();
if(!s.ok()){
log_error("Write error! %s", s.ToString().c_str());
return -1;
}
return 1;
}
int64_t SSDBImpl::_qpush(const Bytes &name, const Bytes &item, uint64_t front_or_back_seq, char log_type){
Transaction trans(binlogs);
int ret;
// generate seq
uint64_t seq;
ret = qget_uint64(this->ldb, name, front_or_back_seq, &seq);
if(ret == -1){
return -1;
}
// update front and/or back
if(ret == 0){
seq = QITEM_SEQ_INIT;
ret = qset_one(this, name, QFRONT_SEQ, Bytes(&seq, sizeof(seq)));
if(ret == -1){
return -1;
}
ret = qset_one(this, name, QBACK_SEQ, Bytes(&seq, sizeof(seq)));
}else{
seq += (front_or_back_seq == QFRONT_SEQ)? -1 : +1;
ret = qset_one(this, name, front_or_back_seq, Bytes(&seq, sizeof(seq)));
}
if(ret == -1){
return -1;
}
if(seq <= QITEM_MIN_SEQ || seq >= QITEM_MAX_SEQ){
log_info("queue is full, seq: %" PRIu64 " out of range", seq);
return -1;
}
// prepend/append item
ret = qset_one(this, name, seq, item);
if(ret == -1){
return -1;
}
std::string buf = encode_qitem_key(name, seq);
if(front_or_back_seq == QFRONT_SEQ){
binlogs->add_log(log_type, BinlogCommand::QPUSH_FRONT, buf);
}else{
binlogs->add_log(log_type, BinlogCommand::QPUSH_BACK, buf);
}
// update size
int64_t size = incr_qsize(this, name, +1);
if(size == -1){
return -1;
}
leveldb::Status s = binlogs->commit();
if(!s.ok()){
log_error("Write error! %s", s.ToString().c_str());
return -1;
}
return size;
}
// @return 0: empty queue, 1: item popped, -1: error
int SSDB::qpop(const Bytes &name, std::string *item){
Transaction trans(binlogs);
int ret;
uint64_t seq;
ret = qget_uint64(this->db, name, QFRONT_SEQ, &seq);
if(ret == -1){
return -1;
}
if(ret == 0){
seq = QITEM_MIN_SEQ;
}
ret = qget(this->db, name, seq, item);
if(ret == -1){
return -1;
}
if(ret == 0){
return 0;
}
// delete item
ret = qdel_one(this, name, seq);
if(ret == -1){
return -1;
}
// update size
int64_t size = incr_qsize(this, name, -1);
if(size == -1){
return -1;
}
// update front
if(size > 0){
seq += 1;
//log_debug("seq: %" PRIu64 ", ret: %d", seq, ret);
ret = qset_one(this, name, QFRONT_SEQ, Bytes(&seq, sizeof(seq)));
if(ret == -1){
return -1;
}
}
leveldb::Status s = binlogs->commit();
if(!s.ok()){
log_error("Write error!");
return -1;
}
return 1;
}
int SSDB::qpush(const Bytes &name, const Bytes &item){
Transaction trans(binlogs);
int ret;
// generate seq
uint64_t seq;
ret = qget_uint64(this->db, name, QBACK_SEQ, &seq);
if(ret == -1){
return -1;
}
if(ret == 0){
seq = QITEM_MIN_SEQ;
}else{
seq += 1;
}
// append item
ret = qset_one(this, name, seq, item);
if(ret == -1){
return -1;
}
// update size
int64_t size = incr_qsize(this, name, +1);
if(size == -1){
return -1;
}
// update back
ret = qset_one(this, name, QBACK_SEQ, Bytes(&seq, sizeof(seq)));
if(ret == -1){
return -1;
}
leveldb::Status s = binlogs->commit();
if(!s.ok()){
log_error("Write error!");
return -1;
}
return 1;
}
