Common c63fb05: Add TCPSocket::connect with timeout

2 files changed, 120 insertions, 1 deletions

diff --git a/lib/Socket.cpp b/lib/Socket.cpp
index 7ff6b5e..d12c970 100644
--- a/lib/Socket.cpp
+++ b/lib/Socket.cpp
@@ -409,6 +409,121 @@ bool TCPSocket::valid() const
     return m_sock != -1;
 }
 
+void TCPSocket::connect(const std::string& hostname, int port, int timeout_ms)
+{
+    if (m_sock != INVALID_SOCKET) {
+        throw std::logic_error("You may only connect an invalid TCPSocket");
+    }
+
+    char service[NI_MAXSERV];
+    snprintf(service, NI_MAXSERV-1, "%d", port);
+
+    /* Obtain address(es) matching host/port */
+    struct addrinfo hints;
+    memset(&hints, 0, sizeof(struct addrinfo));
+    hints.ai_family = AF_INET;
+    hints.ai_socktype = SOCK_STREAM;
+    hints.ai_flags = 0;
+    hints.ai_protocol = 0;
+
+    struct addrinfo *result, *rp;
+    int s = getaddrinfo(hostname.c_str(), service, &hints, &result);
+    if (s != 0) {
+        throw runtime_error(string("getaddrinfo failed: ") + gai_strerror(s));
+    }
+
+    int flags = 0;
+
+    /* getaddrinfo() returns a list of address structures.
+       Try each address until we successfully connect(2).
+       If socket(2) (or connect(2)) fails, we (close the socket
+       and) try the next address. */
+
+    for (rp = result; rp != nullptr; rp = rp->ai_next) {
+        int sfd = ::socket(rp->ai_family, rp->ai_socktype,
+                rp->ai_protocol);
+        if (sfd == -1)
+            continue;
+
+        flags = fcntl(sfd, F_GETFL);
+        if (flags == -1) {
+            std::string errstr(strerror(errno));
+            throw std::runtime_error("TCP: Could not get socket flags: " + errstr);
+        }
+
+        if (fcntl(sfd, F_SETFL, flags | O_NONBLOCK) == -1) {
+            std::string errstr(strerror(errno));
+            throw std::runtime_error("TCP: Could not set O_NONBLOCK: " + errstr);
+        }
+
+        int ret = ::connect(sfd, rp->ai_addr, rp->ai_addrlen);
+        if (ret == 0) {
+            m_sock = sfd;
+            break;
+        }
+        if (ret == -1 and errno == EINPROGRESS) {
+            m_sock = sfd;
+            struct pollfd fds[1];
+            fds[0].fd = m_sock;
+            fds[0].events = POLLOUT;
+
+            int retval = poll(fds, 1, timeout_ms);
+
+            if (retval == -1) {
+                std::string errstr(strerror(errno));
+                ::close(m_sock);
+                freeaddrinfo(result);
+                throw runtime_error("TCP: connect error on poll: " + errstr);
+            }
+            else if (retval > 0) {
+                int so_error = 0;
+                socklen_t len = sizeof(so_error);
+
+                if (getsockopt(m_sock, SOL_SOCKET, SO_ERROR, &so_error, &len) == -1) {
+                    std::string errstr(strerror(errno));
+                    ::close(m_sock);
+                    freeaddrinfo(result);
+                    throw runtime_error("TCP: getsockopt error connect: " + errstr);
+                }
+
+                if (so_error == 0) {
+                    break;
+                }
+            }
+            else {
+                ::close(m_sock);
+                freeaddrinfo(result);
+                throw runtime_error("Timeout on connect");
+            }
+            break;
+        }
+
+        ::close(sfd);
+    }
+
+    if (m_sock != INVALID_SOCKET) {
+#if defined(HAVE_SO_NOSIGPIPE)
+        int val = 1;
+        if (setsockopt(m_sock, SOL_SOCKET, SO_NOSIGPIPE, &val, sizeof(val))
+                == SOCKET_ERROR) {
+            throw runtime_error("Can't set SO_NOSIGPIPE");
+        }
+#endif
+    }
+
+    // Don't keep the socket blocking
+    if (fcntl(m_sock, F_SETFL, flags) == -1) {
+        std::string errstr(strerror(errno));
+        throw std::runtime_error("TCP: Could not set O_NONBLOCK: " + errstr);
+    }
+
+    freeaddrinfo(result);
+
+    if (rp == nullptr) {
+        throw runtime_error("Could not connect");
+    }
+}
+
 void TCPSocket::connect(const std::string& hostname, int port, bool nonblock)
 {
     if (m_sock != INVALID_SOCKET) {
@@ -447,11 +562,15 @@ void TCPSocket::connect(const std::string& hostname, int port, bool nonblock)
             int flags = fcntl(sfd, F_GETFL);
             if (flags == -1) {
                 std::string errstr(strerror(errno));
+                freeaddrinfo(result);
+                ::close(sfd);
                 throw std::runtime_error("TCP: Could not get socket flags: " + errstr);
             }
 
             if (fcntl(sfd, F_SETFL, flags | O_NONBLOCK) == -1) {
                 std::string errstr(strerror(errno));
+                freeaddrinfo(result);
+                ::close(sfd);
                 throw std::runtime_error("TCP: Could not set O_NONBLOCK: " + errstr);
             }
         }
@@ -480,7 +599,6 @@ void TCPSocket::connect(const std::string& hostname, int port, bool nonblock)
     if (rp == nullptr) {
         throw runtime_error("Could not connect");
     }
-
 }
 
 void TCPSocket::listen(int port, const string& name)
diff --git a/lib/Socket.h b/lib/Socket.h
index 33cdc05..08607a5 100644
--- a/lib/Socket.h
+++ b/lib/Socket.h
@@ -168,6 +168,7 @@ class TCPSocket {
 
         bool valid(void) const;
         void connect(const std::string& hostname, int port, bool nonblock = false);
+        void connect(const std::string& hostname, int port, int timeout_ms);
         void listen(int port, const std::string& name);
         void close(void);