simulator: add DNS resolver for ss_ip

src/StratumClient.cc

@@ -50,6 +50,11 @@ StratumClient::StratumClient(
   , isMining_(false) {
   inBuf_ = evbuffer_new();
 
+  evdnsBase_ = evdns_base_new(base, 1);
+  if (evdnsBase_ == nullptr) {
+    LOG(FATAL) << "DNS init failed";
+  }
+
   if (enableTLS_) {
     LOG(INFO) << "<" << workerFullName_ << "> TLS enabled";
 
@@ -95,16 +100,20 @@ StratumClient::StratumClient(
 StratumClient::~StratumClient() {
   evbuffer_free(inBuf_);
   bufferevent_free(bev_);
+  evdns_base_free(evdnsBase_, 0);
 }
 
-bool StratumClient::connect(struct sockaddr_in &sin) {
-  // bufferevent_socket_connect(): This function returns 0 if the connect
-  // was successfully launched, and -1 if an error occurred.
-  int res =
-      bufferevent_socket_connect(bev_, (struct sockaddr *)&sin, sizeof(sin));
+bool StratumClient::connect(const string &host, uint16_t port) {
+  LOG(INFO) << "Connection request to " << host << ":" << port;
+
+  // bufferevent_socket_connect_hostname(): This function returns 0 if the
+  // connect was successfully launched, and -1 if an error occurred.
+  int res = bufferevent_socket_connect_hostname(
+      bev_, evdnsBase_, AF_INET, host.c_str(), (int)port);
   if (res == 0) {
     return true;
   }
+
   return false;
 }
 
@@ -253,7 +262,7 @@ void StratumClient::sendData(const char *data, size_t len) {
 ////////////////////////////// StratumClientWrapper ////////////////////////////
 StratumClientWrapper::StratumClientWrapper(
     bool enableTLS,
-    const char *host,
+    const string &host,
     const uint32_t port,
     const uint32_t numConnections,
     const string &userName,
@@ -263,17 +272,15 @@ StratumClientWrapper::StratumClientWrapper(
     const libconfig::Config &config)
   : running_(true)
   , enableTLS_(enableTLS)
+  , host_(host)
+  , port_(port)
   , base_(event_base_new())
   , numConnections_(numConnections)
   , userName_(userName)
   , minerNamePrefix_(minerNamePrefix)
   , passwd_(passwd)
   , type_(type)
   , config_(config) {
-  memset(&sin_, 0, sizeof(sin_));
-  sin_.sin_family = AF_INET;
-  inet_pton(AF_INET, host, &(sin_.sin_addr));
-  sin_.sin_port = htons(port);
 
   if (minerNamePrefix_.empty())
     minerNamePrefix_ = "simulator";
@@ -345,7 +352,7 @@ void StratumClientWrapper::run() {
         Strings::Format("%s.%s-%05d", userName_, minerNamePrefix_, i);
     auto client = createClient(enableTLS_, base_, workerFullName, passwd_);
 
-    if (!client->connect(sin_)) {
+    if (!client->connect(host_, port_)) {
       LOG(ERROR) << "client connnect failure: " << workerFullName;
       return;
     }

src/StratumClient.h

@@ -34,6 +34,7 @@
 #include <event2/event.h>
 #include <event2/buffer.h>
 #include <event2/bufferevent.h>
+#include <event2/dns.h>
 
 #include <glog/logging.h>
 #include <arith_uint256.h>
@@ -52,6 +53,7 @@ class StratumClient {
   bool enableTLS_;
   struct bufferevent *bev_;
   struct evbuffer *inBuf_;
+  struct evdns_base *evdnsBase_;
 
   uint32_t sessionId_; // session ID
   int32_t extraNonce2Size_;
@@ -118,7 +120,7 @@ class StratumClient {
       const string &workerPasswd);
   virtual ~StratumClient();
 
-  bool connect(struct sockaddr_in &sin);
+  bool connect(const string &host, uint16_t port);
   virtual void sendHelloData();
 
   void sendData(const char *data, size_t len);
@@ -133,8 +135,9 @@ class StratumClient {
 class StratumClientWrapper {
   bool running_;
   bool enableTLS_;
+  string host_;
+  uint16_t port_;
   struct event_base *base_;
-  struct sockaddr_in sin_;
   struct event *timer_;
   struct event *sigterm_;
   struct event *sigint_;
@@ -151,7 +154,7 @@ class StratumClientWrapper {
 public:
   StratumClientWrapper(
       bool enableTLS,
-      const char *host,
+      const string &host,
       const uint32_t port,
       const uint32_t numConnections,
       const string &userName,

src/simulator/simulator.cfg

@@ -10,7 +10,7 @@ simulator = {
   number_clients = 1;
 
   # stratum sever host & port
-  ss_ip = "127.0.0.1";
+  ss_ip = "localhost";
   ss_port = 3333;
   enable_tls = false;