-/*
- The rpcc class handles client-side RPC. Each rpcc is bound to a
- single RPC server. The jobs of rpcc include maintaining a connection to
- server, sending RPC requests and waiting for responses, retransmissions,
- at-most-once delivery etc.
-
- The rpcs class handles the server side of RPC. Each rpcs handles multiple
- connections from different rpcc objects. The jobs of rpcs include accepting
- connections, dispatching requests to registered RPC handlers, at-most-once
- delivery etc.
-
- Both rpcc and rpcs use the connection class as an abstraction for the
- underlying communication channel. To send an RPC request/reply, one calls
- connection::send() which blocks until data is sent or the connection has failed
- (thus the caller can free the buffer when send() returns). When a
- request/reply is received, connection makes a callback into the corresponding
- rpcc or rpcs (see rpcc::got_pdu() and rpcs::got_pdu()).
-
- Thread organization:
- rpcc uses application threads to send RPC requests and blocks to receive the
- reply or error. All connections use a single PollMgr object to perform async
- socket IO. PollMgr creates a single thread to examine the readiness of socket
- file descriptors and informs the corresponding connection whenever a socket is
- ready to be read or written. (We use asynchronous socket IO to reduce the
- number of threads needed to manage these connections; without async IO, at
- least one thread is needed per connection to read data without blocking other
- activities.) Each rpcs object creates one thread for listening on the server
- port and a pool of threads for executing RPC requests. The
- thread pool allows us to control the number of threads spawned at the server
- (spawning one thread per request will hurt when the server faces thousands of
- requests).
-
- In order to delete a connection object, we must maintain a reference count.
- For rpcc,
- multiple client threads might be invoking the rpcc::call() functions and thus
- holding multiple references to the underlying connection object. For rpcs,
- multiple dispatch threads might be holding references to the same connection
- object. A connection object is deleted only when the underlying connection is
- dead and the reference count reaches zero.
-
- The previous version of the RPC library uses pthread_cancel* routines
- to implement the deletion of rpcc and rpcs objects. The idea is to cancel
- all active threads that might be holding a reference to an object before
- deleting that object. However, pthread_cancel is not robust and there are
- always bugs where outstanding references to deleted objects persist.
- This version of the RPC library does not do pthread_cancel, but explicitly
- joins exited threads to make sure no outstanding references exist before
- deleting objects.
-
- To delete a rpcc object safely, the users of the library must ensure that
- there are no outstanding calls on the rpcc object.
-
- To delete a rpcs object safely, we do the following in sequence: 1. stop
- accepting new incoming connections. 2. close existing active connections.
- 3. delete the dispatch thread pool which involves waiting for current active
- RPC handlers to finish. It is interesting how a thread pool can be deleted
- without using thread cancellation. The trick is to inject x "poison pills" for
- a thread pool of x threads. Upon getting a poison pill instead of a normal
- task, a worker thread will exit (and thread pool destructor waits to join all
- x exited worker threads).
- */
+//
+// The rpcc class handles client-side RPC. Each rpcc is bound to a single RPC
+// server. The jobs of rpcc include maintaining a connection to server, sending
+// RPC requests and waiting for responses, retransmissions, at-most-once delivery
+// etc.
+//
+// The rpcs class handles the server side of RPC. Each rpcs handles multiple
+// connections from different rpcc objects. The jobs of rpcs include accepting
+// connections, dispatching requests to registered RPC handlers, at-most-once
+// delivery etc.
+//
+// Both rpcc and rpcs use the connection class as an abstraction for the
+// underlying communication channel. To send an RPC request/reply, one calls
+// connection::send() which blocks until data is sent or the connection has
+// failed (thus the caller can free the buffer when send() returns). When a
+// request/reply is received, connection makes a callback into the corresponding
+// rpcc or rpcs (see rpcc::got_pdu() and rpcs::got_pdu()).
+//
+// Thread organization:
+// rpcc uses application threads to send RPC requests and blocks to receive the
+// reply or error. All connections use a single PollMgr object to perform async
+// socket IO. PollMgr creates a single thread to examine the readiness of socket
+// file descriptors and informs the corresponding connection whenever a socket is
+// ready to be read or written. (We use asynchronous socket IO to reduce the
+// number of threads needed to manage these connections; without async IO, at
+// least one thread is needed per connection to read data without blocking other
+// activities.) Each rpcs object creates one thread for listening on the server
+// port and a pool of threads for executing RPC requests. The thread pool allows
+// us to control the number of threads spawned at the server (spawning one thread
+// per request will hurt when the server faces thousands of requests).
+//
+// In order to delete a connection object, we must maintain a reference count.
+// For rpcc, multiple client threads might be invoking the rpcc::call() functions
+// and thus holding multiple references to the underlying connection object. For
+// rpcs, multiple dispatch threads might be holding references to the same
+// connection object. A connection object is deleted only when the underlying
+// connection is dead and the reference count reaches zero.
+//
+// This version of the RPC library explicitly joins exited threads to make sure
+// no outstanding references exist before deleting objects.
+//
+// To delete a rpcc object safely, the users of the library must ensure that
+// there are no outstanding calls on the rpcc object.
+//
+// To delete a rpcs object safely, we do the following in sequence: 1. stop
+// accepting new incoming connections. 2. close existing active connections. 3.
+// delete the dispatch thread pool which involves waiting for current active RPC
+// handlers to finish. It is interesting how a thread pool can be deleted
+// without using thread cancellation. The trick is to inject x "poison pills" for
+// a thread pool of x threads. Upon getting a poison pill instead of a normal
+// task, a worker thread will exit (and thread pool destructor waits to join all
+// x exited worker threads).
+//
#include "rpc.h"
-#include "method_thread.h"
-#include "slock.h"
-#include <sys/types.h>
#include <arpa/inet.h>
#include <netinet/tcp.h>
-#include <time.h>
#include <netdb.h>
#include <unistd.h>
+#include <string.h>
-#include "jsl_log.h"
-#include "gettime.h"
-#include "lang/verify.h"
-
-const rpcc::TO rpcc::to_max = { 120000 };
-const rpcc::TO rpcc::to_min = { 1000 };
-
-rpcc::caller::caller(unsigned int xxid, unmarshall *xun)
-: xid(xxid), un(xun), done(false)
-{
- VERIFY(pthread_mutex_init(&m,0) == 0);
- VERIFY(pthread_cond_init(&c, 0) == 0);
+inline void set_rand_seed() {
+ auto now = time_point_cast<nanoseconds>(steady_clock::now());
+ srandom((uint32_t)now.time_since_epoch().count()^(uint32_t)getpid());
}
-rpcc::caller::~caller()
-{
- VERIFY(pthread_mutex_destroy(&m) == 0);
- VERIFY(pthread_cond_destroy(&c) == 0);
-}
+static sockaddr_in make_sockaddr(const string & hostandport);
-inline
-void set_rand_seed()
+rpcc::rpcc(const string & d) : dst_(make_sockaddr(d))
{
- struct timespec ts;
- clock_gettime(CLOCK_REALTIME, &ts);
- srandom((int)ts.tv_nsec^((int)getpid()));
-}
+ set_rand_seed();
+ clt_nonce_ = (nonce_t)random();
-rpcc::rpcc(sockaddr_in d, bool retrans) :
- dst_(d), srv_nonce_(0), bind_done_(false), xid_(1), lossytest_(0),
- retrans_(retrans), reachable_(true), chan_(NULL), destroy_wait_ (false), xid_rep_done_(-1)
-{
- VERIFY(pthread_mutex_init(&m_, 0) == 0);
- VERIFY(pthread_mutex_init(&chan_m_, 0) == 0);
- VERIFY(pthread_cond_init(&destroy_wait_c_, 0) == 0);
-
- if(retrans){
- set_rand_seed();
- clt_nonce_ = random();
- } else {
- // special client nonce 0 means this client does not
- // require at-most-once logic from the server
- // because it uses tcp and never retries a failed connection
- clt_nonce_ = 0;
- }
-
- char *loss_env = getenv("RPC_LOSSY");
- if(loss_env != NULL){
- lossytest_ = atoi(loss_env);
- }
-
- // xid starts with 1 and latest received reply starts with 0
- xid_rep_window_.push_back(0);
-
- jsl_log(JSL_DBG_2, "rpcc::rpcc cltn_nonce is %d lossy %d\n",
- clt_nonce_, lossytest_);
+ char *loss_env = getenv("RPC_LOSSY");
+ if (loss_env)
+ lossytest_ = atoi(loss_env);
+
+ IF_LEVEL(2) LOG("cltn_nonce is " << clt_nonce_ << " lossy " << lossytest_);
}
// IMPORTANT: destruction should happen only when no external threads
// are blocked inside rpcc or will use rpcc in the future
-rpcc::~rpcc()
-{
- jsl_log(JSL_DBG_2, "rpcc::~rpcc delete nonce %d channo=%d\n",
- clt_nonce_, chan_?chan_->channo():-1);
- if(chan_){
- chan_->closeconn();
- chan_->decref();
- }
- VERIFY(calls_.size() == 0);
- VERIFY(pthread_mutex_destroy(&m_) == 0);
- VERIFY(pthread_mutex_destroy(&chan_m_) == 0);
-}
-
-int
-rpcc::bind(TO to)
-{
- int r;
- int ret = call(rpc_const::bind, 0, r, to);
- if(ret == 0){
- ScopedLock ml(&m_);
- bind_done_ = true;
- srv_nonce_ = r;
- } else {
- jsl_log(JSL_DBG_2, "rpcc::bind %s failed %d\n",
- inet_ntoa(dst_.sin_addr), ret);
- }
- return ret;
+rpcc::~rpcc() {
+ cancel();
+ IF_LEVEL(2) LOG("delete nonce " << clt_nonce_ << " chan " << (chan_?(int)chan_->fd:-1));
+ chan_.reset();
+ VERIFY(calls_.size() == 0);
+}
+
+int rpcc::bind(milliseconds to) {
+ nonce_t r;
+ rpc_protocol::status ret = call_timeout(rpc_protocol::bind, to, r);
+ if (ret == 0) {
+ lock ml(m_);
+ bind_done_ = true;
+ srv_nonce_ = r;
+ } else {
+ IF_LEVEL(2) LOG("bind " << inet_ntoa(dst_.sin_addr) << " failed " << ret);
+ }
+ return ret;
};
// Cancel all outstanding calls
-void
-rpcc::cancel(void)
-{
- ScopedLock ml(&m_);
- printf("rpcc::cancel: force callers to fail\n");
- std::map<int,caller*>::iterator iter;
- for(iter = calls_.begin(); iter != calls_.end(); iter++){
- caller *ca = iter->second;
+void rpcc::cancel(void) {
+ lock ml(m_);
+ if (calls_.size()) {
+ LOG("force callers to fail");
+ for (auto & p : calls_) {
+ caller *ca = p.second;
+
+ IF_LEVEL(2) LOG("force caller to fail");
+
+ lock cl(ca->m);
+ ca->done = true;
+ ca->intret = rpc_protocol::cancel_failure;
+ ca->c.notify_one();
+ }
- jsl_log(JSL_DBG_2, "rpcc::cancel: force caller to fail\n");
+ destroy_wait_ = true;
+ while (calls_.size () > 0)
+ destroy_wait_c_.wait(ml);
+
+ LOG("done");
+ }
+}
+
+int rpcc::call1(proc_id_t proc, milliseconds to, string & rep, marshall & req) {
+
+ caller ca(0, &rep);
+ xid_t xid_rep;
{
- ScopedLock cl(&ca->m);
- ca->done = true;
- ca->intret = rpc_const::cancel_failure;
- VERIFY(pthread_cond_signal(&ca->c) == 0);
+ lock ml(m_);
+
+ if ((proc != rpc_protocol::bind.id && !bind_done_) || (proc == rpc_protocol::bind.id && bind_done_)) {
+ IF_LEVEL(1) LOG("rpcc has not been bound to dst or binding twice");
+ return rpc_protocol::bind_failure;
+ }
+
+ if (destroy_wait_)
+ return rpc_protocol::cancel_failure;
+
+ ca.xid = xid_++;
+ calls_[ca.xid] = &ca;
+
+ req.pack_header(rpc_protocol::request_header{
+ ca.xid, proc, clt_nonce_, srv_nonce_, xid_rep_window_.front()
+ });
+ xid_rep = xid_rep_window_.front();
}
- }
- while (calls_.size () > 0){
- destroy_wait_ = true;
- VERIFY(pthread_cond_wait(&destroy_wait_c_,&m_) == 0);
- }
- printf("rpcc::cancel: done\n");
-}
+ milliseconds curr_to = rpc::to_min;
+ auto finaldeadline = steady_clock::now() + to;
+
+ bool transmit = true;
+ shared_ptr<connection> ch;
+
+ while (1) {
+ if (transmit) {
+ get_latest_connection(ch);
+ if (ch) {
+ if (reachable_) {
+ request forgot;
+ {
+ lock ml(m_);
+ if (dup_req_.isvalid() && xid_rep_done_ > dup_req_.xid) {
+ forgot = dup_req_;
+ dup_req_.clear();
+ }
+ }
+ if (forgot.isvalid())
+ ch->send(forgot.buf);
+ ch->send(req);
+ }
+ else IF_LEVEL(1) LOG("not reachable");
+ IF_LEVEL(2) LOG(clt_nonce_ << " just sent req proc " << hex << proc <<
+ " xid " << dec << ca.xid << " clt_nonce " << clt_nonce_);
+ }
+ transmit = false; // only send once on a given channel
+ }
-int
-rpcc::call1(unsigned int proc, marshall &req, unmarshall &rep,
- TO to)
-{
+ auto nextdeadline = min(steady_clock::now() + curr_to, finaldeadline);
+ curr_to *= 2;
- caller ca(0, &rep);
- int xid_rep;
- {
- ScopedLock ml(&m_);
-
- if((proc != rpc_const::bind && !bind_done_) ||
- (proc == rpc_const::bind && bind_done_)){
- jsl_log(JSL_DBG_1, "rpcc::call1 rpcc has not been bound to dst or binding twice\n");
- return rpc_const::bind_failure;
- }
-
- if(destroy_wait_){
- return rpc_const::cancel_failure;
- }
-
- ca.xid = xid_++;
- calls_[ca.xid] = &ca;
-
- req_header h(ca.xid, proc, clt_nonce_, srv_nonce_,
- xid_rep_window_.front());
- req.pack_req_header(h);
- xid_rep = xid_rep_window_.front();
- }
-
- TO curr_to;
- struct timespec now, nextdeadline, finaldeadline;
-
- clock_gettime(CLOCK_REALTIME, &now);
- add_timespec(now, to.to, &finaldeadline);
- curr_to.to = to_min.to;
-
- bool transmit = true;
- connection *ch = NULL;
-
- while (1){
- if(transmit){
- get_refconn(&ch);
- if(ch){
- if(reachable_) {
- request forgot;
- {
- ScopedLock ml(&m_);
- if (dup_req_.isvalid() && xid_rep_done_ > dup_req_.xid) {
- forgot = dup_req_;
- dup_req_.clear();
- }
- }
- if (forgot.isvalid())
- ch->send((char *)forgot.buf.c_str(), forgot.buf.size());
- ch->send(req.cstr(), req.size());
- }
- else jsl_log(JSL_DBG_1, "not reachable\n");
- jsl_log(JSL_DBG_2,
- "rpcc::call1 %u just sent req proc %x xid %u clt_nonce %d\n",
- clt_nonce_, proc, ca.xid, clt_nonce_);
- }
- transmit = false; // only send once on a given channel
- }
-
- if(!finaldeadline.tv_sec)
- break;
-
- clock_gettime(CLOCK_REALTIME, &now);
- add_timespec(now, curr_to.to, &nextdeadline);
- if(cmp_timespec(nextdeadline,finaldeadline) > 0){
- nextdeadline = finaldeadline;
- finaldeadline.tv_sec = 0;
- }
-
- {
- ScopedLock cal(&ca.m);
- while (!ca.done){
- jsl_log(JSL_DBG_2, "rpcc:call1: wait\n");
- if(pthread_cond_timedwait(&ca.c, &ca.m,
- &nextdeadline) == ETIMEDOUT){
- jsl_log(JSL_DBG_2, "rpcc::call1: timeout\n");
- break;
- }
- }
- if(ca.done){
- jsl_log(JSL_DBG_2, "rpcc::call1: reply received\n");
- break;
- }
- }
-
- if(retrans_ && (!ch || ch->isdead())){
- // since connection is dead, retransmit
- // on the new connection
- transmit = true;
- }
- curr_to.to <<= 1;
- }
-
- {
- // no locking of ca.m since only this thread changes ca.xid
- ScopedLock ml(&m_);
- calls_.erase(ca.xid);
- // may need to update the xid again here, in case the
- // packet times out before it's even sent by the channel.
- // I don't think there's any harm in maybe doing it twice
- update_xid_rep(ca.xid);
-
- if(destroy_wait_){
- VERIFY(pthread_cond_signal(&destroy_wait_c_) == 0);
- }
- }
-
- if (ca.done && lossytest_)
{
- ScopedLock ml(&m_);
- if (!dup_req_.isvalid()) {
- dup_req_.buf.assign(req.cstr(), req.size());
- dup_req_.xid = ca.xid;
+ lock cal(ca.m);
+ while (!ca.done) {
+ IF_LEVEL(2) LOG("wait");
+ if (ca.c.wait_until(cal, nextdeadline) == cv_status::timeout) {
+ IF_LEVEL(2) LOG("timeout");
+ break;
}
- if (xid_rep > xid_rep_done_)
- xid_rep_done_ = xid_rep;
+ }
+ if (ca.done) {
+ IF_LEVEL(2) LOG("reply received");
+ break;
+ }
}
- ScopedLock cal(&ca.m);
+ if (nextdeadline >= finaldeadline)
+ break;
+
+ // retransmit on new connection if connection is dead
+ if (!ch || ch->isdead())
+ transmit = true;
+ }
+
+ {
+ // no locking of ca.m since only this thread changes ca.xid
+ lock ml(m_);
+ calls_.erase(ca.xid);
+ // may need to update the xid again here, in case the
+ // packet times out before it's even sent by the channel.
+ // I don't think there's any harm in maybe doing it twice
+ update_xid_rep(ca.xid, ml);
+
+ if (destroy_wait_)
+ destroy_wait_c_.notify_one();
+ }
+
+ if (ca.done && lossytest_)
+ {
+ lock ml(m_);
+ if (!dup_req_.isvalid()) {
+ dup_req_.buf = req;
+ dup_req_.xid = ca.xid;
+ }
+ if (xid_rep > xid_rep_done_)
+ xid_rep_done_ = xid_rep;
+ }
- jsl_log(JSL_DBG_2,
- "rpcc::call1 %u call done for req proc %x xid %u %s:%d done? %d ret %d \n",
- clt_nonce_, proc, ca.xid, inet_ntoa(dst_.sin_addr),
- ntohs(dst_.sin_port), ca.done, ca.intret);
+ lock cal(ca.m);
- if(ch)
- ch->decref();
+ IF_LEVEL(2) LOG(clt_nonce_ << " call done for req proc " << hex << proc <<
+ " xid " << dec << ca.xid << " " << inet_ntoa(dst_.sin_addr) << ":" <<
+ ntoh(dst_.sin_port) << " done? " << ca.done << " ret " << ca.intret);
- // destruction of req automatically frees its buffer
- return (ca.done? ca.intret : rpc_const::timeout_failure);
+ // destruction of req automatically frees its buffer
+ return (ca.done? ca.intret : rpc_protocol::timeout_failure);
}
-void
-rpcc::get_refconn(connection **ch)
-{
- ScopedLock ml(&chan_m_);
- if(!chan_ || chan_->isdead()){
- if(chan_)
- chan_->decref();
- chan_ = connect_to_dst(dst_, this, lossytest_);
- }
- if(ch && chan_){
- if(*ch){
- (*ch)->decref();
- }
- *ch = chan_;
- (*ch)->incref();
- }
+void rpcc::get_latest_connection(shared_ptr<connection> & ch) {
+ lock ml(chan_m_);
+ if (!chan_ || chan_->isdead())
+ chan_ = connection::to_dst(dst_, this, lossytest_);
+
+ if (chan_)
+ ch = chan_;
}
-// PollMgr's thread is being used to
-// make this upcall from connection object to rpcc.
+// PollMgr's thread is being used to
+// make this upcall from connection object to rpcc.
// this funtion must not block.
//
-// this function keeps no reference for connection *c
+// this function keeps no reference for connection *c
bool
-rpcc::got_pdu(connection *c, char *b, int sz)
+rpcc::got_pdu(const shared_ptr<connection> &, const string & b)
{
- unmarshall rep(b, sz);
- reply_header h;
- rep.unpack_reply_header(&h);
-
- if(!rep.ok()){
- jsl_log(JSL_DBG_1, "rpcc:got_pdu unmarshall header failed!!!\n");
- return true;
- }
-
- ScopedLock ml(&m_);
-
- update_xid_rep(h.xid);
-
- if(calls_.find(h.xid) == calls_.end()){
- jsl_log(JSL_DBG_2, "rpcc::got_pdu xid %d no pending request\n", h.xid);
- return true;
- }
- caller *ca = calls_[h.xid];
-
- ScopedLock cl(&ca->m);
- if(!ca->done){
- ca->un->take_in(rep);
- ca->intret = h.ret;
- if(ca->intret < 0){
- jsl_log(JSL_DBG_2, "rpcc::got_pdu: RPC reply error for xid %d intret %d\n",
- h.xid, ca->intret);
- }
- ca->done = 1;
- }
- VERIFY(pthread_cond_broadcast(&ca->c) == 0);
- return true;
-}
+ unmarshall rep(b, true);
+ rpc_protocol::reply_header h;
+ rep.unpack_header(h);
-// assumes thread holds mutex m
-void
-rpcc::update_xid_rep(unsigned int xid)
-{
- std::list<unsigned int>::iterator it;
+ if (!rep.ok()) {
+ IF_LEVEL(1) LOG("unmarshall header failed!!!");
+ return true;
+ }
- if(xid <= xid_rep_window_.front()){
- return;
- }
+ lock ml(m_);
- for (it = xid_rep_window_.begin(); it != xid_rep_window_.end(); it++){
- if(*it > xid){
- xid_rep_window_.insert(it, xid);
- goto compress;
- }
- }
- xid_rep_window_.push_back(xid);
+ update_xid_rep(h.xid, ml);
-compress:
- it = xid_rep_window_.begin();
- for (it++; it != xid_rep_window_.end(); it++){
- while (xid_rep_window_.front() + 1 == *it)
- xid_rep_window_.pop_front();
- }
+ if (calls_.find(h.xid) == calls_.end()) {
+ IF_LEVEL(2) LOG("xid " << h.xid << " no pending request");
+ return true;
+ }
+ caller *ca = calls_[h.xid];
+
+ lock cl(ca->m);
+ if (!ca->done) {
+ *ca->rep = b;
+ ca->intret = h.ret;
+ if (ca->intret < 0) {
+ IF_LEVEL(2) LOG("RPC reply error for xid " << h.xid << " intret " << ca->intret);
+ }
+ ca->done = 1;
+ }
+ ca->c.notify_all();
+ return true;
}
+void rpcc::update_xid_rep(xid_t xid, lock & m_lock) {
+ VERIFY(m_lock);
+ if (xid <= xid_rep_window_.front())
+ return;
-rpcs::rpcs(unsigned int p1, int count)
- : port_(p1), counting_(count), curr_counts_(count), lossytest_(0), reachable_ (true)
-{
- VERIFY(pthread_mutex_init(&procs_m_, 0) == 0);
- VERIFY(pthread_mutex_init(&count_m_, 0) == 0);
- VERIFY(pthread_mutex_init(&reply_window_m_, 0) == 0);
- VERIFY(pthread_mutex_init(&conss_m_, 0) == 0);
+ for (auto it = xid_rep_window_.begin(); it != xid_rep_window_.end(); it++) {
+ if (*it > xid) {
+ xid_rep_window_.insert(it, xid);
+ goto compress;
+ }
+ }
+ xid_rep_window_.push_back(xid);
- set_rand_seed();
- nonce_ = random();
- jsl_log(JSL_DBG_2, "rpcs::rpcs created with nonce %d\n", nonce_);
+compress:
+ auto it = xid_rep_window_.begin();
+ for (it++; it != xid_rep_window_.end(); it++) {
+ while (xid_rep_window_.front() + 1 == *it)
+ xid_rep_window_.pop_front();
+ }
+}
- char *loss_env = getenv("RPC_LOSSY");
- if(loss_env != NULL){
- lossytest_ = atoi(loss_env);
- }
+rpcs::rpcs(in_port_t p1) : port_(p1)
+{
+ set_rand_seed();
+ nonce_ = (nonce_t)random();
+ IF_LEVEL(2) LOG("created with nonce " << nonce_);
- reg(rpc_const::bind, this, &rpcs::rpcbind);
- dispatchpool_ = new ThrPool(6,false);
+ reg(rpc_protocol::bind, &rpcs::rpcbind, this);
+}
- listener_ = new tcpsconn(this, port_, lossytest_);
+void rpcs::start() {
+ char *loss_env = getenv("RPC_LOSSY");
+ listener_.reset(new connection_listener(this, port_, loss_env ? atoi(loss_env) : 0));
}
-rpcs::~rpcs()
-{
- // must delete listener before dispatchpool
- delete listener_;
- delete dispatchpool_;
- free_reply_window();
+rpcs::~rpcs() {
+ // must delete listener before dispatchpool
+ listener_ = nullptr;
+ dispatchpool_ = nullptr;
}
-bool
-rpcs::got_pdu(connection *c, char *b, int sz)
-{
- if(!reachable_){
- jsl_log(JSL_DBG_1, "rpcss::got_pdu: not reachable\n");
- return true;
- }
+bool rpcs::got_pdu(const shared_ptr<connection> & c, const string & b) {
+ if (!reachable_) {
+ IF_LEVEL(1) LOG("not reachable");
+ return true;
+ }
- djob_t *j = new djob_t(c, b, sz);
- c->incref();
- bool succ = dispatchpool_->addObjJob(this, &rpcs::dispatch, j);
- if(!succ || !reachable_){
- c->decref();
- delete j;
- }
- return succ;
+ return dispatchpool_->addJob(std::bind(&rpcs::dispatch, this, c, b));
}
-void
-rpcs::reg1(unsigned int proc, handler *h)
-{
- ScopedLock pl(&procs_m_);
- VERIFY(procs_.count(proc) == 0);
- procs_[proc] = h;
- VERIFY(procs_.count(proc) >= 1);
-}
+void rpcs::dispatch(shared_ptr<connection> c, const string & buf) {
+ unmarshall req(buf, true);
-void
-rpcs::updatestat(unsigned int proc)
-{
- ScopedLock cl(&count_m_);
- counts_[proc]++;
- curr_counts_--;
- if(curr_counts_ == 0){
- std::map<int, int>::iterator i;
- printf("RPC STATS: ");
- for (i = counts_.begin(); i != counts_.end(); i++){
- printf("%x:%d ", i->first, i->second);
- }
- printf("\n");
-
- ScopedLock rwl(&reply_window_m_);
- std::map<unsigned int,std::list<reply_t> >::iterator clt;
-
- unsigned int totalrep = 0, maxrep = 0;
- for (clt = reply_window_.begin(); clt != reply_window_.end(); clt++){
- totalrep += clt->second.size();
- if(clt->second.size() > maxrep)
- maxrep = clt->second.size();
- }
- jsl_log(JSL_DBG_1, "REPLY WINDOW: clients %d total reply %d max per client %d\n",
- (int) reply_window_.size()-1, totalrep, maxrep);
- curr_counts_ = counting_;
- }
-}
+ rpc_protocol::request_header h;
+ req.unpack_header(h);
+ proc_id_t proc = h.proc;
-void
-rpcs::dispatch(djob_t *j)
-{
- connection *c = j->conn;
- unmarshall req(j->buf, j->sz);
- delete j;
-
- req_header h;
- req.unpack_req_header(&h);
- int proc = h.proc;
-
- if(!req.ok()){
- jsl_log(JSL_DBG_1, "rpcs:dispatch unmarshall header failed!!!\n");
- c->decref();
- return;
- }
-
- jsl_log(JSL_DBG_2,
- "rpcs::dispatch: rpc %u (proc %x, last_rep %u) from clt %u for srv instance %u \n",
- h.xid, proc, h.xid_rep, h.clt_nonce, h.srv_nonce);
-
- marshall rep;
- reply_header rh(h.xid,0);
-
- // is client sending to an old instance of server?
- if(h.srv_nonce != 0 && h.srv_nonce != nonce_){
- jsl_log(JSL_DBG_2,
- "rpcs::dispatch: rpc for an old server instance %u (current %u) proc %x\n",
- h.srv_nonce, nonce_, h.proc);
- rh.ret = rpc_const::oldsrv_failure;
- rep.pack_reply_header(rh);
- c->send(rep.cstr(),rep.size());
- return;
- }
-
- handler *f;
- // is RPC proc a registered procedure?
- {
- ScopedLock pl(&procs_m_);
- if(procs_.count(proc) < 1){
- fprintf(stderr, "rpcs::dispatch: unknown proc %x.\n",
- proc);
- c->decref();
- VERIFY(0);
- return;
- }
-
- f = procs_[proc];
- }
-
- rpcs::rpcstate_t stat;
- char *b1;
- int sz1;
-
- if(h.clt_nonce){
- // have i seen this client before?
- {
- ScopedLock rwl(&reply_window_m_);
- // if we don't know about this clt_nonce, create a cleanup object
- if(reply_window_.find(h.clt_nonce) == reply_window_.end()){
- VERIFY (reply_window_[h.clt_nonce].size() == 0); // create
- reply_window_[h.clt_nonce].push_back(reply_t(-1)); // store starting reply xid
- jsl_log(JSL_DBG_2,
- "rpcs::dispatch: new client %u xid %d chan %d, total clients %d\n",
- h.clt_nonce, h.xid, c->channo(), (int)reply_window_.size()-1);
- }
- }
-
- // save the latest good connection to the client
- {
- ScopedLock rwl(&conss_m_);
- if(conns_.find(h.clt_nonce) == conns_.end()){
- c->incref();
- conns_[h.clt_nonce] = c;
- } else if(conns_[h.clt_nonce]->compare(c) < 0){
- conns_[h.clt_nonce]->decref();
- c->incref();
- conns_[h.clt_nonce] = c;
- }
- }
-
- stat = checkduplicate_and_update(h.clt_nonce, h.xid,
- h.xid_rep, &b1, &sz1);
- } else {
- // this client does not require at most once logic
- stat = NEW;
- }
-
- switch (stat){
- case NEW: // new request
- if(counting_){
- updatestat(proc);
- }
-
- rh.ret = f->fn(req, rep);
- if (rh.ret == rpc_const::unmarshal_args_failure) {
- fprintf(stderr, "rpcs::dispatch: failed to"
- " unmarshall the arguments. You are"
- " probably calling RPC 0x%x with wrong"
- " types of arguments.\n", proc);
- VERIFY(0);
- }
- VERIFY(rh.ret >= 0);
-
- rep.pack_reply_header(rh);
- rep.take_buf(&b1,&sz1);
-
- jsl_log(JSL_DBG_2,
- "rpcs::dispatch: sending and saving reply of size %d for rpc %u, proc %x ret %d, clt %u\n",
- sz1, h.xid, proc, rh.ret, h.clt_nonce);
-
- if(h.clt_nonce > 0){
- // only record replies for clients that require at-most-once logic
- add_reply(h.clt_nonce, h.xid, b1, sz1);
- }
-
- // get the latest connection to the client
- {
- ScopedLock rwl(&conss_m_);
- if(c->isdead() && c != conns_[h.clt_nonce]){
- c->decref();
- c = conns_[h.clt_nonce];
- c->incref();
- }
- }
-
- c->send(b1, sz1);
- if(h.clt_nonce == 0){
- // reply is not added to at-most-once window, free it
- free(b1);
- }
- break;
- case INPROGRESS: // server is working on this request
- break;
- case DONE: // duplicate and we still have the response
- c->send(b1, sz1);
- break;
- case FORGOTTEN: // very old request and we don't have the response anymore
- jsl_log(JSL_DBG_2, "rpcs::dispatch: very old request %u from %u\n",
- h.xid, h.clt_nonce);
- rh.ret = rpc_const::atmostonce_failure;
- rep.pack_reply_header(rh);
- c->send(rep.cstr(),rep.size());
- break;
- }
- c->decref();
+ if (!req.ok()) {
+ IF_LEVEL(1) LOG("unmarshall header failed");
+ return;
+ }
+
+ IF_LEVEL(2) LOG("rpc " << h.xid << " (proc " << hex << proc << ", last_rep " <<
+ dec << h.xid_rep << ") from clt " << h.clt_nonce << " for srv instance " << h.srv_nonce);
+
+ marshall rep;
+ rpc_protocol::reply_header rh{h.xid,0};
+
+ // is client sending to an old instance of server?
+ if (h.srv_nonce != 0 && h.srv_nonce != nonce_) {
+ IF_LEVEL(2) LOG("rpc for an old server instance " << h.srv_nonce <<
+ " (current " << nonce_ << ") proc " << hex << h.proc);
+ rh.ret = rpc_protocol::oldsrv_failure;
+ rep.pack_header(rh);
+ c->send(rep);
+ return;
+ }
+
+ handler *f;
+ // is RPC proc a registered procedure?
+ {
+ lock pl(procs_m_);
+ if (procs_.count(proc) < 1) {
+ LOG("unknown proc 0x" << hex << proc << " with h.srv_nonce=" << h.srv_nonce << ", my srv_nonce=" << nonce_);
+ VERIFY(0);
+ return;
+ }
+
+ f = procs_[proc];
+ }
+
+ // have i seen this client before?
+ {
+ lock rwl(reply_window_m_);
+ // if we don't know about this clt_nonce, create a cleanup object
+ if (reply_window_.find(h.clt_nonce) == reply_window_.end()) {
+ VERIFY (reply_window_[h.clt_nonce].size() == 0); // create
+ reply_window_[h.clt_nonce].push_back(reply_t(-1)); // store starting reply xid
+ IF_LEVEL(2) LOG("new client " << h.clt_nonce << " xid " << h.xid <<
+ " chan " << c->fd << ", total clients " << (reply_window_.size()-1));
+ }
+ }
+
+ // save the latest good connection to the client
+ {
+ lock rwl(conns_m_);
+ if (conns_.find(h.clt_nonce) == conns_.end())
+ conns_[h.clt_nonce] = c;
+ else if (conns_[h.clt_nonce]->create_time < c->create_time)
+ conns_[h.clt_nonce] = c;
+ }
+
+ string b1;
+
+ switch (check_duplicate_and_update(h.clt_nonce, h.xid, h.xid_rep, b1)) {
+ case NEW: // new request
+ rh.ret = (*f)(forward<unmarshall>(req), rep);
+ if (rh.ret == rpc_protocol::unmarshall_args_failure) {
+ LOG("failed to unmarshall the arguments. You are " <<
+ "probably calling RPC 0x" << hex << proc << " with the wrong " <<
+ "types of arguments.");
+ VERIFY(0);
+ }
+ VERIFY(rh.ret >= 0);
+
+ rep.pack_header(rh);
+ b1 = rep;
+
+ IF_LEVEL(2) LOG("sending and saving reply of size " << b1.size() << " for rpc " <<
+ h.xid << ", proc " << hex << proc << " ret " << dec << rh.ret << ", clt " << h.clt_nonce);
+
+ add_reply(h.clt_nonce, h.xid, b1);
+
+ // get the latest connection to the client
+ {
+ lock rwl(conns_m_);
+ if (c->isdead())
+ c = conns_[h.clt_nonce];
+ }
+
+ c->send(rep);
+ break;
+ case INPROGRESS: // server is working on this request
+ break;
+ case DONE: // duplicate and we still have the response
+ c->send(b1);
+ break;
+ case FORGOTTEN: // very old request and we don't have the response anymore
+ IF_LEVEL(2) LOG("very old request " << h.xid << " from " << h.clt_nonce);
+ rh.ret = rpc_protocol::atmostonce_failure;
+ rep.pack_header(rh);
+ c->send(rep);
+ break;
+ }
}
// rpcs::dispatch calls this when an RPC request arrives.
// returns one of:
// NEW: never seen this xid before.
// INPROGRESS: seen this xid, and still processing it.
-// DONE: seen this xid, previous reply returned in *b and *sz.
+// DONE: seen this xid, previous reply returned in b.
// FORGOTTEN: might have seen this xid, but deleted previous reply.
-rpcs::rpcstate_t
-rpcs::checkduplicate_and_update(unsigned int clt_nonce, unsigned int xid,
- unsigned int xid_rep, char **b, int *sz)
+rpcs::rpcstate_t
+rpcs::check_duplicate_and_update(nonce_t clt_nonce, xid_t xid,
+ xid_t xid_rep, string & b)
{
- ScopedLock rwl(&reply_window_m_);
+ lock rwl(reply_window_m_);
- std::list<reply_t> &l = reply_window_[clt_nonce];
+ list<reply_t> & l = reply_window_[clt_nonce];
VERIFY(l.size() > 0);
VERIFY(xid >= xid_rep);
- unsigned int past_xid_rep = l.begin()->xid;
+ xid_t past_xid_rep = l.begin()->xid;
- std::list<reply_t>::iterator start = l.begin(), it;
- it = ++start;
+ list<reply_t>::iterator start = l.begin(), it = ++start;
- if (past_xid_rep < xid_rep || past_xid_rep == (unsigned int)-1) {
+ if (past_xid_rep < xid_rep || past_xid_rep == -1) {
// scan for deletion candidates
- for (; it != l.end() && it->xid < xid_rep; it++) {
- if (it->cb_present)
- free(it->buf);
- }
+ while (it != l.end() && it->xid < xid_rep)
+ it++;
l.erase(start, it);
l.begin()->xid = xid_rep;
}
- if (xid < past_xid_rep && past_xid_rep != (unsigned int)-1)
+ if (xid < past_xid_rep && past_xid_rep != -1)
return FORGOTTEN;
// skip non-deletion candidates
if (it != l.end() && it->xid == xid) {
if (it->cb_present) {
// return information about the remembered reply
- *b = it->buf;
- *sz = it->sz;
+ b = it->buf;
return DONE;
- } else {
- return INPROGRESS;
}
+ return INPROGRESS;
} else {
// remember that a new request has arrived
l.insert(it, reply_t(xid));
}
// rpcs::dispatch calls add_reply when it is sending a reply to an RPC,
-// and passes the return value in b and sz.
-// add_reply() should remember b and sz.
-// free_reply_window() and checkduplicate_and_update is responsible for
-// calling free(b).
-void
-rpcs::add_reply(unsigned int clt_nonce, unsigned int xid,
- char *b, int sz)
-{
- ScopedLock rwl(&reply_window_m_);
+// and passes the return value in b.
+// add_reply() should remember b.
+void rpcs::add_reply(nonce_t clt_nonce, xid_t xid, const string & b) {
+ lock rwl(reply_window_m_);
// remember the RPC reply value
- std::list<reply_t> &l = reply_window_[clt_nonce];
- std::list<reply_t>::iterator it = l.begin();
+ list<reply_t> & l = reply_window_[clt_nonce];
+ list<reply_t>::iterator it = l.begin();
// skip to our place in the list
for (it++; it != l.end() && it->xid < xid; it++);
// there should already be an entry, so whine if there isn't
if (it == l.end() || it->xid != xid) {
- fprintf(stderr, "Could not find reply struct in add_reply");
- l.insert(it, reply_t(xid, b, sz));
+ LOG("Could not find reply struct in add_reply");
+ l.insert(it, reply_t(xid, b));
} else {
- *it = reply_t(xid, b, sz);
+ *it = reply_t(xid, b);
}
}
-void
-rpcs::free_reply_window(void)
-{
- std::map<unsigned int,std::list<reply_t> >::iterator clt;
- std::list<reply_t>::iterator it;
-
- ScopedLock rwl(&reply_window_m_);
- for (clt = reply_window_.begin(); clt != reply_window_.end(); clt++){
- for (it = clt->second.begin(); it != clt->second.end(); it++){
- if (it->cb_present)
- free(it->buf);
- }
- clt->second.clear();
- }
- reply_window_.clear();
-}
-
-// rpc handler
-int
-rpcs::rpcbind(int a, int &r)
-{
- jsl_log(JSL_DBG_2, "rpcs::rpcbind called return nonce %u\n", nonce_);
- r = nonce_;
- return 0;
-}
-
-void
-marshall::rawbyte(unsigned char x)
-{
- if(_ind >= _capa){
- _capa *= 2;
- VERIFY (_buf != NULL);
- _buf = (char *)realloc(_buf, _capa);
- VERIFY(_buf);
- }
- _buf[_ind++] = x;
-}
-
-void
-marshall::rawbytes(const char *p, int n)
-{
- if((_ind+n) > _capa){
- _capa = _capa > n? 2*_capa:(_capa+n);
- VERIFY (_buf != NULL);
- _buf = (char *)realloc(_buf, _capa);
- VERIFY(_buf);
- }
- memcpy(_buf+_ind, p, n);
- _ind += n;
-}
-
-marshall &
-operator<<(marshall &m, bool x)
-{
- m.rawbyte(x);
- return m;
-}
-
-marshall &
-operator<<(marshall &m, unsigned char x)
-{
- m.rawbyte(x);
- return m;
-}
-
-marshall &
-operator<<(marshall &m, char x)
-{
- m << (unsigned char) x;
- return m;
-}
-
-
-marshall &
-operator<<(marshall &m, unsigned short x)
-{
- m.rawbyte((x >> 8) & 0xff);
- m.rawbyte(x & 0xff);
- return m;
-}
-
-marshall &
-operator<<(marshall &m, short x)
-{
- m << (unsigned short) x;
- return m;
-}
-
-marshall &
-operator<<(marshall &m, unsigned int x)
-{
- // network order is big-endian
- m.rawbyte((x >> 24) & 0xff);
- m.rawbyte((x >> 16) & 0xff);
- m.rawbyte((x >> 8) & 0xff);
- m.rawbyte(x & 0xff);
- return m;
-}
-
-marshall &
-operator<<(marshall &m, int x)
-{
- m << (unsigned int) x;
- return m;
-}
-
-marshall &
-operator<<(marshall &m, const std::string &s)
-{
- m << (unsigned int) s.size();
- m.rawbytes(s.data(), s.size());
- return m;
-}
-
-marshall &
-operator<<(marshall &m, unsigned long long x)
-{
- m << (unsigned int) (x >> 32);
- m << (unsigned int) x;
- return m;
-}
-
-void
-marshall::pack(int x)
-{
- rawbyte((x >> 24) & 0xff);
- rawbyte((x >> 16) & 0xff);
- rawbyte((x >> 8) & 0xff);
- rawbyte(x & 0xff);
-}
-
-void
-unmarshall::unpack(int *x)
-{
- (*x) = (rawbyte() & 0xff) << 24;
- (*x) |= (rawbyte() & 0xff) << 16;
- (*x) |= (rawbyte() & 0xff) << 8;
- (*x) |= rawbyte() & 0xff;
-}
-
-// take the contents from another unmarshall object
-void
-unmarshall::take_in(unmarshall &another)
-{
- if(_buf)
- free(_buf);
- another.take_buf(&_buf, &_sz);
- _ind = RPC_HEADER_SZ;
- _ok = _sz >= RPC_HEADER_SZ?true:false;
-}
-
-bool
-unmarshall::okdone()
-{
- if(ok() && _ind == _sz){
- return true;
- } else {
- return false;
- }
+rpc_protocol::status rpcs::rpcbind(nonce_t & r) {
+ IF_LEVEL(2) LOG("called return nonce " << nonce_);
+ r = nonce_;
+ return 0;
}
-unsigned int
-unmarshall::rawbyte()
-{
- char c = 0;
- if(_ind >= _sz)
- _ok = false;
- else
- c = _buf[_ind++];
- return c;
-}
-
-unmarshall &
-operator>>(unmarshall &u, bool &x)
-{
- x = (bool) u.rawbyte() ;
- return u;
-}
-
-unmarshall &
-operator>>(unmarshall &u, unsigned char &x)
-{
- x = (unsigned char) u.rawbyte() ;
- return u;
-}
-
-unmarshall &
-operator>>(unmarshall &u, char &x)
-{
- x = (char) u.rawbyte();
- return u;
-}
-
-
-unmarshall &
-operator>>(unmarshall &u, unsigned short &x)
-{
- x = (u.rawbyte() & 0xff) << 8;
- x |= u.rawbyte() & 0xff;
- return u;
-}
-
-unmarshall &
-operator>>(unmarshall &u, short &x)
-{
- x = (u.rawbyte() & 0xff) << 8;
- x |= u.rawbyte() & 0xff;
- return u;
-}
-
-unmarshall &
-operator>>(unmarshall &u, unsigned int &x)
-{
- x = (u.rawbyte() & 0xff) << 24;
- x |= (u.rawbyte() & 0xff) << 16;
- x |= (u.rawbyte() & 0xff) << 8;
- x |= u.rawbyte() & 0xff;
- return u;
-}
-
-unmarshall &
-operator>>(unmarshall &u, int &x)
-{
- x = (u.rawbyte() & 0xff) << 24;
- x |= (u.rawbyte() & 0xff) << 16;
- x |= (u.rawbyte() & 0xff) << 8;
- x |= u.rawbyte() & 0xff;
- return u;
-}
-
-unmarshall &
-operator>>(unmarshall &u, unsigned long long &x)
-{
- unsigned int h, l;
- u >> h;
- u >> l;
- x = l | ((unsigned long long) h << 32);
- return u;
-}
-
-unmarshall &
-operator>>(unmarshall &u, std::string &s)
-{
- unsigned sz;
- u >> sz;
- if(u.ok())
- u.rawbytes(s, sz);
- return u;
-}
-
-void
-unmarshall::rawbytes(std::string &ss, unsigned int n)
-{
- if((_ind+n) > (unsigned)_sz){
- _ok = false;
- } else {
- std::string tmps = std::string(_buf+_ind, n);
- swap(ss, tmps);
- VERIFY(ss.size() == n);
- _ind += n;
- }
-}
-
-bool operator<(const sockaddr_in &a, const sockaddr_in &b){
- return ((a.sin_addr.s_addr < b.sin_addr.s_addr) ||
- ((a.sin_addr.s_addr == b.sin_addr.s_addr) &&
- ((a.sin_port < b.sin_port))));
-}
-
-/*---------------auxilary function--------------*/
-void
-make_sockaddr(const char *hostandport, struct sockaddr_in *dst){
-
- char host[200];
- const char *localhost = "127.0.0.1";
- const char *port = index(hostandport, ':');
- if(port == NULL){
- memcpy(host, localhost, strlen(localhost)+1);
- port = hostandport;
- } else {
- memcpy(host, hostandport, port-hostandport);
- host[port-hostandport] = '\0';
- port++;
- }
-
- make_sockaddr(host, port, dst);
-
-}
+static sockaddr_in make_sockaddr(const string & hostandport) {
+ string host = "127.0.0.1";
+ string port = hostandport;
+ auto colon = hostandport.find(':');
+ if (colon != string::npos) {
+ host = hostandport.substr(0, colon);
+ port = hostandport.substr(colon+1);
+ }
-void
-make_sockaddr(const char *host, const char *port, struct sockaddr_in *dst){
-
- in_addr_t a;
-
- bzero(dst, sizeof(*dst));
- dst->sin_family = AF_INET;
-
- a = inet_addr(host);
- if(a != INADDR_NONE){
- dst->sin_addr.s_addr = a;
- } else {
- struct hostent *hp = gethostbyname(host);
- if(hp == 0 || hp->h_length != 4){
- fprintf(stderr, "cannot find host name %s\n", host);
- exit(1);
- }
- dst->sin_addr.s_addr = ((struct in_addr *)(hp->h_addr))->s_addr;
- }
- dst->sin_port = htons(atoi(port));
-}
+ sockaddr_in dst{}; // zero initialize
+ dst.sin_family = AF_INET;
-int
-cmp_timespec(const struct timespec &a, const struct timespec &b)
-{
- if(a.tv_sec > b.tv_sec)
- return 1;
- else if(a.tv_sec < b.tv_sec)
- return -1;
- else {
- if(a.tv_nsec > b.tv_nsec)
- return 1;
- else if(a.tv_nsec < b.tv_nsec)
- return -1;
- else
- return 0;
- }
-}
+ struct in_addr a{inet_addr(host.c_str())};
-void
-add_timespec(const struct timespec &a, int b, struct timespec *result)
-{
- // convert to millisec, add timeout, convert back
- result->tv_sec = a.tv_sec + b/1000;
- result->tv_nsec = a.tv_nsec + (b % 1000) * 1000000;
- VERIFY(result->tv_nsec >= 0);
- while (result->tv_nsec > 1000000000){
- result->tv_sec++;
- result->tv_nsec-=1000000000;
- }
-}
+ if (a.s_addr != INADDR_NONE)
+ dst.sin_addr.s_addr = a.s_addr;
+ else {
+ struct hostent *hp = gethostbyname(host.c_str());
-int
-diff_timespec(const struct timespec &end, const struct timespec &start)
-{
- int diff = (end.tv_sec > start.tv_sec)?(end.tv_sec-start.tv_sec)*1000:0;
- VERIFY(diff || end.tv_sec == start.tv_sec);
- if(end.tv_nsec > start.tv_nsec){
- diff += (end.tv_nsec-start.tv_nsec)/1000000;
- } else {
- diff -= (start.tv_nsec-end.tv_nsec)/1000000;
- }
- return diff;
+ if (!hp || hp->h_length != 4 || hp->h_addrtype != AF_INET) {
+ LOG_NONMEMBER("cannot find host name " << host);
+ exit(1);
+ }
+ memcpy(&a, hp->h_addr_list[0], sizeof(in_addr_t));
+ dst.sin_addr.s_addr = a.s_addr;
+ }
+ dst.sin_port = hton((in_port_t)stoi(port));
+ return dst;
}