本文整理汇总了C++中DB::Open方法的典型用法代码示例。如果您正苦于以下问题：C++ DB::Open方法的具体用法？C++ DB::Open怎么用？C++ DB::Open使用的例子？那么, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类DB的用法示例。
在下文中一共展示了DB::Open方法的2个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的C++代码示例。
示例1: main
int main()
{
char neterr[ANET_ERR_LEN];
struct epoll_event ev;
int listenfd;
if(!db.Open("mydb")){
cerr<<"db open failed:"<<endl;
return 0;
}
signal(SIGPIPE, SIG_IGN); //ignore sigpipe to prevent server shut down
thread_pool.Run();
if((listenfd = anetTcpServer(neterr, 9999, NULL)) == ANET_ERR){
fprintf(stderr, "%s\n", neterr);
exit(1);
}
anetNonBlock(neterr, listenfd);
if((epfd = epoll_create(MAX_CLIENTS)) < 0){
perror("epoll_create");
exit(1);
}
ev.events = EPOLLIN;
ev.data.fd =listenfd;
if(epoll_ctl(epfd, EPOLL_CTL_ADD, listenfd, &ev)<0){
perror("epoll_ctl");
exit(1);
}
for(;;){
int nfds = epoll_wait(epfd, events, MAX_CLIENTS, -1);
for(int i = 0; i < nfds; ++i) {
int fd = events[i].data.fd;
if(fd == listenfd) {
struct sockaddr_in cliaddr;
socklen_t addrlen = sizeof(cliaddr);
int connfd = accept(listenfd, (struct sockaddr *) &cliaddr, &addrlen);
if(connfd < 0){
if(errno == ECONNABORTED) //connection aborted, ignore it
continue;
else if(errno == EAGAIN) //no connections are ready to be accepted
continue;
else{ //error happened in accept, report it
perror("accept");
continue;
}
}
fprintf(stderr, "a new connfd: %d\n", connfd);
anetNonBlock(neterr, connfd);
ev.events = EPOLLIN;
ev.data.fd = connfd;
if (epoll_ctl(epfd, EPOLL_CTL_ADD, connfd, &ev) < 0) {
perror("epoll_ctl");
return -1;
}
clients[connfd].fd = connfd;
nclients++;
}
else if(events[i].events & EPOLLIN)
{
int n;
char* rbuf = clients[fd].readbuf;
while ((n = read(fd, rbuf+clients[fd].rpos, MAX_BUFLEN-clients[fd].rpos)) > 0)
clients[fd].rpos += n;
if (n == 0) { //client has been closed
fprintf(stderr, "client has been closed, so server also close it, fd=%d\n", fd);
close(fd);
nclients--;
}
if (n<0 && errno != EAGAIN) {
perror("read");
close(fd);
nclients--;
}
int res = handle_read_event(&clients[fd]);
if(res<0){ //error happened
fprintf(stderr, "bad command, res=%d\n", res);
close(fd);
nclients--;
}else if(res>0){ //the command has been hand over to a background thread, nothing to do here
}else{ //res == 0, needs more data, continue reading
}
}
else if(events[i].events & EPOLLOUT)
{
char* wbuf = clients[fd].writebuf;
int wend = clients[fd].wend;
int n;
//.........这里部分代码省略.........
示例2: main
int main(int argc, char* argv[])
{
const char* dbname;
const char* verifykey = NULL;
union {
unsigned char buf[64];
uint256_t hash;
};
std::vector<node_t> nodes;
std::vector<node_t>::const_iterator it;
int idx, cnt, pos;
int mode = MODE_ROOT;
char *ptr;
DB* db;
if(argc<2) {
fprintf(stderr, "Usage: %s <dbname> [key=verifier key] [<position>|<hash>|root|dump|gendata]\n", argv[0]);
return 0;
}
dbname = argv[1];
for(idx=2; idx<argc; ++idx) {
if(!strncmp(argv[idx], "key=", 4)) {
verifykey = argv[idx] + 4;
} else if(!strcmp(argv[idx], "dump")) {
mode = MODE_DUMP;
} else if(!strcmp(argv[idx], "root")) {
mode = MODE_ROOT;
} else if(!strcmp(argv[idx], "gendata")) {
mode = MODE_GENTESTDATA;
} else if(sizeof(uint256_t)*2==strlen(argv[idx])) {
if(!HexData(argv[idx], buf, sizeof(buf))) {
fprintf(stderr, "Invalid hash value: %s\n", argv[idx]);
return 0;
}
mode = MODE_HASH;
} else if(argv[idx][0]>='0' && argv[idx][0]<='9') {
pos = strtol(argv[idx], &ptr, 10);
if(ptr && *ptr) {
fprintf(stderr, "Invalid position value: %s\n", argv[idx]);
return 0;
}
mode = MODE_POSITION;
} else {
fprintf(stderr, "Unknown option: %s\n", argv[idx]);
return 0;
}
}
if(MODE_GENTESTDATA==mode) {
if(!GenTestData(dbname))
fprintf(stderr, "Error generating data\n");
}
db = new DB(dbname, verifykey);
if(!db->Open()) {
fprintf(stderr, "Open DB failed\n");
delete(db);
return 0;
}
switch(mode) {
case MODE_HASH:
if(db->GetNodes(hash, nodes)) {
idx = 0;
for(idx=0,it=nodes.begin(); idx<nodes.size(); idx+=2) {
fprintf(stdout, "%d: ", idx/2);
if(idx+1<nodes.size()) {
ShowHex(it->hash, sizeof(it->hash), false);
++it;
fprintf(stdout, " / ");
}
ShowHex(it->hash, sizeof(it->hash), true);
++it;
}
} else
fprintf(stderr, "Hash not found\n");
break;
case MODE_POSITION:
if(db->GetNodes(pos, nodes)) {
idx = 0;
for(idx=0,it=nodes.begin(); idx<nodes.size(); idx+=2) {
fprintf(stdout, "%d: ", idx/2);
if(idx+1<nodes.size()) {
ShowHex(it->hash, sizeof(it->hash), false);
++it;
fprintf(stdout, " / ");
}
ShowHex(it->hash, sizeof(it->hash), true);
++it;
}
} else
fprintf(stderr, "Error reading tree\n");
break;
case MODE_ROOT:
if(db->GetRoot(nodes)) {
fprintf(stdout, "Root %ld: ", nodes[2].data.value);
//.........这里部分代码省略.........