static int64_t incr_qsize(SSDBImpl *ssdb, const Bytes &name, int64_t incr){
int64_t size = ssdb->qsize(name);
if(size == -1){
return -1;
}
size += incr;
if(size <= 0){
ssdb->binlogs->Delete(encode_qsize_key(name));
qdel_one(ssdb, name, QFRONT_SEQ);
qdel_one(ssdb, name, QBACK_SEQ);
}else{
ssdb->binlogs->Put(encode_qsize_key(name), leveldb::Slice((char *)&size, sizeof(size)));
}
return size;
}
int SSDB::qfix(const Bytes &name){
Transaction trans(binlogs);
std::string key_s = encode_qitem_key(name, QITEM_MIN_SEQ - 1);
std::string key_e = encode_qitem_key(name, QITEM_MAX_SEQ);
bool error = false;
uint64_t seq_min = 0;
uint64_t seq_max = 0;
uint64_t count = 0;
Iterator *it = this->iterator(key_s, key_e, QITEM_MAX_SEQ);
while(it->next()){
//dump(it->key().data(), it->key().size());
if(seq_min == 0){
if(decode_qitem_key(it->key(), NULL, &seq_min) == -1){
// or just delete it?
error = true;
break;
}
}
if(decode_qitem_key(it->key(), NULL, &seq_max) == -1){
error = true;
break;
}
count ++;
}
delete it;
if(error){
return -1;
}
if(count == 0){
this->binlogs->Delete(encode_qsize_key(name));
qdel_one(this, name, QFRONT_SEQ);
qdel_one(this, name, QBACK_SEQ);
}else{
this->binlogs->Put(encode_qsize_key(name), leveldb::Slice((char *)&count, sizeof(count)));
qset_one(this, name, QFRONT_SEQ, Bytes(&seq_min, sizeof(seq_min)));
qset_one(this, name, QBACK_SEQ, Bytes(&seq_max, sizeof(seq_max)));
}
leveldb::Status s = binlogs->commit();
if(!s.ok()){
log_error("Write error!");
return -1;
}
return 0;
}
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;
}
// @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;
}