restructure and add server/client example

shared/src/TcpSocket.cpp

@@ -0,0 +1,169 @@
+
+#include <arpa/inet.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <netdb.h>
+
+#include <string>
+#include <functional>
+#include <cerrno>
+#include <cstring>
+#include <thread>
+
+namespace TcpSocket
+{
+
+  void setTimeout(int seconds, int sock)
+  {
+    struct timeval tv;
+    tv.tv_sec = seconds;
+    tv.tv_usec = 0;
+
+    setsockopt(sock, SOL_SOCKET, SO_RCVTIMEO, (char *)&tv, sizeof(tv));
+    setsockopt(sock, SOL_SOCKET, SO_SNDTIMEO, (char *)&tv, sizeof(tv));
+  }
+
+  ssize_t sendt(int sock, const void *bytes, size_t byteslength) { return send(sock, bytes, byteslength, 0); }
+
+  ssize_t recvt(int sock, void *bytes, size_t byteslength) { return recv(sock, bytes, byteslength, 0); }
+
+  void closet(int sock)
+  {
+    shutdown(sock, SHUT_RDWR);
+    close(sock);
+  }
+
+  std::string remoteAddress(sockaddr_in &address)
+  {
+    char ip[INET_ADDRSTRLEN];
+    inet_ntop(AF_INET, &(address.sin_addr), ip, INET_ADDRSTRLEN);
+
+    return std::string(ip);
+  }
+
+  int remotePort(sockaddr_in &address) { return ntohs(address.sin_port); }
+
+  int connectt(const char *host, uint16_t port)
+  {
+    struct addrinfo hints, *res, *it;
+    memset(&hints, 0, sizeof(hints));
+    hints.ai_family = AF_INET;
+    hints.ai_socktype = SOCK_STREAM;
+
+    // Get address info from DNS
+    int status = getaddrinfo(host, NULL, &hints, &res);
+    if (status != 0)
+    {
+      // onError(errno, "Invalid address." + std::string(gai_strerror(status)));
+      return -1;
+    }
+
+    sockaddr_in address;
+    for (it = res; it != NULL; it = it->ai_next)
+    {
+      if (it->ai_family == AF_INET)
+      { // IPv4
+        memcpy((void *)(&address), (void *)it->ai_addr, sizeof(sockaddr_in));
+        break; // for now, just get the first ip (ipv4).
+      }
+    }
+
+    freeaddrinfo(res);
+
+    int sock = socket(AF_INET, SOCK_STREAM, 0);
+
+    if (sock == -1)
+    {
+      // onError(errno, "Socket creating error.");
+      return -2;
+    }
+
+    address.sin_family = AF_INET;
+    address.sin_port = htons(port);
+
+    // setTimeout(5, sock);
+
+    // Try to connect.
+    status = connect(sock, (const sockaddr *)&address, sizeof(sockaddr_in));
+    if (status == -1)
+    {
+      // onError(errno, "Connection failed to the host.");
+      close(sock);
+      return -3;
+    }
+    return sock;
+  }
+
+  typedef std::function<void(int sock, sockaddr_in newSocketInfo)> OnNewConnectionCallBack;
+
+  int listent(const char *host, uint16_t port, OnNewConnectionCallBack callback)
+  {
+    sockaddr_in address;
+
+    int sock = socket(AF_INET, SOCK_STREAM, 0);
+
+    if (sock == -1)
+    {
+      // onError(errno, "Socket creating error.");
+      return -1;
+    }
+
+    int opt = 1;
+    setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(int));
+    setsockopt(sock, SOL_SOCKET, SO_REUSEPORT, &opt, sizeof(int));
+
+    int status = inet_pton(AF_INET, host, &address.sin_addr);
+    switch (status)
+    {
+    case -1:
+      close(sock);
+      // onError(errno, "Invalid address. Address type not supported.");
+      return -2;
+    case 0:
+      close(sock);
+      // onError(errno, "AF_INET is not supported. Please send message to developer.");
+      return -3;
+    default:
+      break;
+    }
+
+    address.sin_family = AF_INET;
+    address.sin_port = htons(port);
+
+    if (bind(sock, (const sockaddr *)&address, sizeof(address)) == -1)
+    {
+      // onError(errno, "Cannot bind the socket.");
+      close(sock);
+      return -4;
+    }
+    if (listen(sock, 20) == -1)
+    {
+      // onError(errno, "Error: Server can't listen the socket.");
+      close(sock);
+      return -5;
+    }
+
+    sockaddr_in newSocketInfo;
+    socklen_t newSocketInfoLength = sizeof(newSocketInfo);
+
+    int newSocketFileDescriptor = -1;
+    while (true)
+    {
+      newSocketFileDescriptor = accept(sock, (sockaddr *)&newSocketInfo, &newSocketInfoLength);
+      if (newSocketFileDescriptor == -1)
+      {
+        if (errno == EBADF || errno == EINVAL)
+          return -6;
+
+        return -7;
+      }
+
+      std::thread t(callback, newSocketFileDescriptor, newSocketInfo);
+      t.detach();
+    }
+
+    return 0;
+  }
+
+}