DNSEntry DNSServer::getDNS(const std::string& domain) const {
std::shared_lock<std::shared_timed_mutex> lockguard(data_mutex);
DNSEntry entry = -1;
try {
entry = data.at(domain);
}
catch(const std::exception& ex){
}
return entry;
}
static
struct servent *getservbyname_r(const char *name,
const char *proto,
struct servent *result,
bsl::vector<char> *buffer)
// Re-entrant version of 'getservbyname', with a private improvement that
// it never fails with ERANGE but instead resizes 'buffer' as needed.
// Return 'result' with all entries filled in upon success, and 0 if
// 'getservbyname' fails.
{
static BloombergLP::bslmt::Mutex mutex;
BloombergLP::bslmt::LockGuard<BloombergLP::bslmt::Mutex> lockguard(&mutex);
struct servent *server = getservbyname(const_cast<char *>(name),
const_cast<char *>(proto));
if (0 == server) {
return 0; // RETURN
}
char **alias;
int len = 0;
// Compute size of server data and resize 'buffer' if necessary.
len += bsl::strlen(server->s_proto) + 1;
len += bsl::strlen(server->s_name) + 1;
len += sizeof alias;
for (alias = server->s_aliases; *alias != 0; ++alias) {
len += sizeof *alias + bsl::strlen(*alias) + 1;
}
if (len > buffer->size()) {
buffer->reserve(len); // to force capacity == len,
buffer->resize(len); // otherwise the resize may round capacity
// to smallest power of two not smaller than len
}
// Buffer is large enough; copy server data, and set 'result' pointers.
char *sp = &buffer->front() +
(1 + alias - server->s_aliases) * sizeof *alias;
char **ap = reinterpret_cast<char **>(&buffer->front());
bsl::strcpy(sp, server->s_name);
result->s_name = sp;
sp += bsl::strlen(sp) + 1;
bsl::strcpy(sp, server->s_proto);
result->s_proto = sp;
sp += bsl::strlen(sp) + 1;
result->s_aliases = ap;
for (alias = server->s_aliases; *alias != 0; ++alias) {
bsl::strcpy(sp, *alias);
*ap++ = sp;
sp += bsl::strlen(sp) + 1;
}
*ap = 0;
result->s_port = server->s_port;
return result;
}
void DNSServer::newEntry(const std::string& domain, const DNSEntry& dns) {
std::lock_guard<std::shared_timed_mutex> lockguard(data_mutex);
data.insert(std::pair<std::string, DNSEntry>(domain, dns));
}
