tcp_sink windows impl

include/spdlog/details/tcp_client-windows.h

+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#define WIN32_LEAN_AND_MEAN
+// tcp client helper
+#include <spdlog/common.h>
+#include <spdlog/details/os.h>
+
+#include <windows.h>
+#include <winsock2.h>
+#include <ws2tcpip.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string>
+
+// Need to link with Ws2_32.lib, Mswsock.lib, and Advapi32.lib
+#pragma comment(lib, "Ws2_32.lib")
+#pragma comment(lib, "Mswsock.lib")
+#pragma comment(lib, "AdvApi32.lib")
+
+namespace spdlog {
+namespace details {
+class tcp_client
+{
+    SOCKET socket_ = INVALID_SOCKET;
+
+    static bool winsock_initialized_()
+    {
+        SOCKET s = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
+        if (s == INVALID_SOCKET)
+        {
+            return false;
+        }
+        else
+        {
+            closesocket(s);
+            return true;
+        }
+    }
+
+    static void init_winsock_()
+    {
+        WSADATA wsaData;
+        auto rv = WSAStartup(MAKEWORD(2, 2), &wsaData);
+        if (rv != 0)
+        {
+            throw_winsock_error_("WSAStartup failed", ::WSAGetLastError());
+        }
+    }
+
+    static void throw_winsock_error_(const std::string& msg, int last_error)
+    {
+        char buf[512];
+        ::FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS, 
+            NULL,
+            last_error,
+            MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), 
+            buf, (sizeof(buf) / sizeof(char)), NULL);
+
+        SPDLOG_THROW(spdlog_ex(fmt::format("tcp_sink - {}: {}", msg, buf)));
+    }
+
+public:
+    bool is_connected() const
+    {
+        return socket_ != INVALID_SOCKET;
+    }
+
+    void close()
+    {
+        ::closesocket(socket_);
+        socket_ = INVALID_SOCKET;
+        WSACleanup();
+    }
+
+    SOCKET fd() const
+    {
+        return socket_;
+    }
+
+    ~tcp_client()
+    {
+        close();
+    }
+
+    // try to connect or throw on failure
+    void connect(const std::string &host, int port)
+    {
+        // initialize winsock if needed
+        if (!winsock_initialized_())
+        {
+            init_winsock_();
+        }
+
+        if (is_connected())
+        {
+            close();
+        }
+        struct addrinfo hints
+        {};
+        ZeroMemory(&hints, sizeof(hints));
+
+        hints.ai_family = AF_INET;       // IPv4
+        hints.ai_socktype = SOCK_STREAM; // TCP
+        hints.ai_flags = AI_NUMERICSERV; // port passed as as numeric value
+        hints.ai_protocol = 0;
+
+        auto port_str = std::to_string(port);
+        struct addrinfo *addrinfo_result;
+        auto rv = ::getaddrinfo(host.c_str(), port_str.c_str(), &hints, &addrinfo_result);
+        int last_error = 0;
+        if (rv != 0)
+        {            
+            last_error = ::WSAGetLastError();
+            WSACleanup();
+            throw_winsock_error_("getaddrinfo failed", last_error);
+        }
+
+        // Try each address until we successfully connect(2).
+        
+        for (auto *rp = addrinfo_result; rp != nullptr; rp = rp->ai_next)
+        {
+            socket_ = socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol);
+            if (socket_ == INVALID_SOCKET)
+            {
+                last_error = ::WSAGetLastError();                
+                WSACleanup();
+                continue;
+            }
+            if (::connect(socket_, rp->ai_addr, (int)rp->ai_addrlen) == 0)
+            {
+                break;
+            }
+            else
+            {
+                last_error = ::WSAGetLastError();
+                close();
+            }
+        }
+        ::freeaddrinfo(addrinfo_result);
+        if (socket_ == INVALID_SOCKET)
+        {
+            WSACleanup();            
+            throw_winsock_error_("connect failed", last_error);
+        }
+
+        // set TCP_NODELAY
+        int enable_flag = 1;
+        ::setsockopt(socket_, IPPROTO_TCP, TCP_NODELAY, (char *)&enable_flag, sizeof(enable_flag));
+    }
+
+    // Send exactly n_bytes of the given data.
+    // On error close the connection and throw.
+    void send(const char *data, size_t n_bytes)
+    {
+        size_t bytes_sent = 0;
+        while (bytes_sent < n_bytes)
+        {
+            const int send_flags = 0;
+            auto write_result = ::send(socket_, data + bytes_sent, (int)(n_bytes - bytes_sent), send_flags);
+            if (write_result == SOCKET_ERROR)
+            {                
+                int last_error = ::WSAGetLastError();
+                close();
+                throw_winsock_error_("send failed", last_error);
+            }
+
+            if (write_result == 0) // (probably should not happen but in any case..)
+            {
+                break;
+            }
+            bytes_sent += static_cast<size_t>(write_result);
+        }
+    }
+};
+} // namespace details
+} // namespace spdlog
\ No newline at end of file

include/spdlog/sinks/tcp_sink.h

@@ -6,7 +6,12 @@
 #include <spdlog/common.h>
 #include <spdlog/sinks/base_sink.h>
 #include <spdlog/details/null_mutex.h>
+#ifdef _WIN32
+#include <spdlog/details/tcp_client-windows.h>
+#else
 #include <spdlog/details/tcp_client.h>
+#endif
+
 #include <mutex>
 #include <string>
 #include <chrono>
@@ -26,11 +31,12 @@ struct tcp_sink_config
 {
     std::string server_host;
     int server_port;
-    bool lazy_connect = false; // connect on first log call instead of in construction
+    bool lazy_connect;  // connect on first log call instead of in construction
 
-    tcp_sink_config(std::string host, int port)
+    tcp_sink_config(std::string host, int port, bool lazy_connect)
         : server_host{std::move(host)}
         , server_port{port}
+        , lazy_connect{lazy_connect}
     {}
 };
 
@@ -40,8 +46,9 @@ class tcp_sink : public spdlog::sinks::base_sink<Mutex>
 public:
     // connect to tcp host/port or throw if failed
     // host can be hostname or ip address
-    explicit tcp_sink(tcp_sink_config sink_config)
-        : config_{std::move(sink_config)}
+
+    explicit tcp_sink(tcp_sink_config sink_config):
+        config_{std::move(sink_config)}
     {
         if (!config_.lazy_connect)
         {
@@ -49,6 +56,8 @@ public:
         }
     }
 
+  
+
     ~tcp_sink() override = default;
 
 protected: