Merge pull request #597 from Qv2ray/dev-nonblock-TCPing

add nonblocking TCPing

makespec/BUILDVERSION

@@ -1 +1 @@
-5366
+5367

src/components/latency/QvTCPing.cpp

@@ -2,7 +2,9 @@
     #include <WS2tcpip.h>
     #include <WinSock2.h>
 #else
+    #include <fcntl.h>
     #include <netdb.h>
+    #include <sys/select.h>
     #include <sys/socket.h>
     #include <sys/time.h>
     #include <unistd.h>
@@ -11,6 +13,110 @@
 #include "QvTCPing.hpp"
 #include "core/handler/ConfigHandler.hpp"
 
+#ifdef _WIN32
+using qv_socket_t = SOCKET;
+#else
+using qv_socket_t = int;
+#endif
+namespace
+{
+    inline int setnonblocking(qv_socket_t sockno, int &opt)
+    {
+#ifdef _WIN32
+        ULONG block = 1;
+        if (ioctlsocket(sockno, FIONBIO, &block) == SOCKET_ERROR)
+        {
+            return -1;
+        }
+#else
+        if ((opt = fcntl(sockno, F_GETFL, NULL)) < 0)
+        {
+            // get socket flags
+            return -1;
+        }
+        if (fcntl(sockno, F_SETFL, opt | O_NONBLOCK) < 0)
+        {
+            // set socket non-blocking
+            return -1;
+        }
+#endif
+        return 0;
+    }
+
+    inline int setblocking(qv_socket_t sockno, int &opt)
+    {
+#ifdef _WIN32
+        ULONG block = 0;
+        if (ioctlsocket(sockno, FIONBIO, &block) == SOCKET_ERROR)
+        {
+            return -1;
+        }
+#else
+        if (fcntl(sockno, F_SETFL, opt) < 0)
+        {
+            // reset socket flags
+            return -1;
+        }
+#endif
+        return 0;
+    }
+
+    int connect_wait(qv_socket_t sockno, struct sockaddr *addr, size_t addrlen, int timeout_sec = 5)
+    {
+        int res;
+        int opt;
+        timeval tv = { 0 };
+        tv.tv_sec = timeout_sec;
+        tv.tv_usec = 0;
+        if ((res = setnonblocking(sockno, opt)) != 0)
+            return -1;
+        if ((res = ::connect(sockno, addr, addrlen)) < 0)
+        {
+#ifdef _WIN32
+            if (WSAGetLastError() != WSAEWOULDBLOCK)
+            {
+#else
+            if (errno == EINPROGRESS)
+            {
+#endif
+                // connecting
+                fd_set wait_set;
+                FD_ZERO(&wait_set);
+                FD_SET(sockno, &wait_set);
+                res = select(sockno + 1, NULL, &wait_set, NULL, &tv);
+            }
+        }
+        else
+        {
+            // connect immediately
+            res = 1;
+        }
+        if (setblocking(sockno, opt) != 0)
+        {
+            return -1;
+        }
+        if (res < 0)
+        {
+            // an error occured
+            return -1;
+        }
+        else if (res == 0)
+        {
+            // timeout
+            return 1;
+        }
+        else
+        {
+            socklen_t len = sizeof(opt);
+            if (getsockopt(sockno, SOL_SOCKET, SO_ERROR, reinterpret_cast<char *>(&opt), &len) < 0)
+            {
+                return -1;
+            }
+        }
+        return 0;
+    }
+} // namespace
+
 namespace Qv2ray::components::tcping
 {
     static int resolveHost(const std::string &host, int portnr, struct addrinfo **res);
@@ -159,11 +265,8 @@ namespace Qv2ray::components::tcping
 
     int testLatency(struct addrinfo *addr, std::chrono::system_clock::time_point *start, std::chrono::system_clock::time_point *end)
     {
-#ifdef _WIN32
-        SOCKET fd;
-#else
-        int fd;
-#endif
+        qv_socket_t fd;
+
         const int on = 1;
         /* int flags; */
         int rv = 0;
@@ -198,7 +301,7 @@ namespace Qv2ray::components::tcping
             /* connect to peer */
             // Qt has its own connect() function in QObject....
             // So we add "::" here
-            if (::connect(fd, addr->ai_addr, addr->ai_addrlen) == 0)
+            if (connect_wait(fd, addr->ai_addr, addr->ai_addrlen) == 0)
             {
                 *end = system_clock::now();
 #ifdef Q_OS_WIN