Added net directory to initial implementation of c-libp2p-network.

net/socket.c

@@ -0,0 +1,109 @@
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <unistd.h>
+#include <stdint.h>
+#include <string.h>
+#include <arpa/inet.h>
+#include "socket.h"
+
+/* Create a TCP socket.
+ */
+int socket_tcp4(void)
+{
+   int s;
+
+   s = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);
+   if (s == -1) return -1;
+   return s;
+}
+
+/* associate an IP address with an port to a socket.
+ * first param is the socket file description
+ * second is an array of four bytes IP address
+ * in binary format, this function return 0 on sucess
+ * or -1 on error setting errno apropriated.
+ */
+int socket_bind4(int s, uint32_t ip, uint16_t port)
+{
+   struct sockaddr_in sa;
+
+   bzero(&sa, sizeof sa);
+   sa.sin_family = AF_INET;
+   sa.sin_port = htons(port);
+   sa.sin_addr.s_addr = ip;
+
+   return bind(s, (struct sockaddr *) &sa, sizeof sa);
+}
+
+/* Same as socket_bind4(), but set SO_REUSEADDR before
+ */
+int socket_bind4_reuse(int s, uint32_t ip, uint16_t port)
+{
+   int opt = 1;
+   setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof opt);
+   return socket_bind4(s, ip, port);
+}
+
+/* Accept a connection in a socket and return ip and port of
+ * remote connection at pointers passed as parameters.
+ */
+int socket_accept4(int s, uint32_t *ip, uint16_t *port)
+{
+   struct sockaddr_in sa;
+   socklen_t dummy = sizeof sa;
+   int fd;
+
+   fd = accept(s, (struct sockaddr *) &sa, &dummy);
+   if (fd == -1) return -1;
+
+   *ip = sa.sin_addr.s_addr;
+   *port = ntohs(sa.sin_port);
+
+   return fd;
+}
+
+/* retrieve local ip and port information from a socket.
+ */
+int socket_local4(int s, uint32_t *ip, uint16_t *port)
+{
+   struct sockaddr_in sa;
+   socklen_t dummy = sizeof sa;
+
+   if (getsockname(s, (struct sockaddr *) &sa, &dummy) == -1) return -1;
+   *ip = sa.sin_addr.s_addr;
+   *port = ntohs(sa.sin_port);
+   return 0;
+}
+
+/* start a client connection.
+ */
+int socket_connect4(int s, uint32_t ip, uint16_t port)
+{
+   struct sockaddr_in sa;
+
+   memset(&sa, 0, sizeof sa);
+   sa.sin_family = AF_INET;
+   sa.sin_port = htons(port);
+   sa.sin_addr.s_addr = ip;
+
+   return connect(s, (struct sockaddr *) &sa, sizeof sa);
+}
+
+/* bind and listen to a socket.
+ */
+int socket_listen(int s, uint32_t *localip, uint16_t *localport)
+{
+   if (socket_bind4_reuse(s, *localip, *localport) == -1) {
+      close(s);
+      return -1;
+   }
+   if (socket_local4(s, localip, localport) == -1) {
+      close(s);
+      return -1;
+   }
+   if (listen(s, 1) == -1) {
+      close(s);
+      return -1;
+   }
+   return s;
+}

net/socket.h

@@ -0,0 +1,11 @@
+#ifndef SOCKET_H
+   #define SOCKET_H
+
+   int socket_tcp4(void);
+   int socket_bind4(int s, uint32_t ip, uint16_t port);
+   int socket_bind4_reuse(int s, uint32_t ip, uint16_t port);
+   int socket_accept4(int s, uint32_t *ip, uint16_t *port);
+   int socket_local4(int s, uint32_t *ip, uint16_t *port);
+   int socket_connect4(int s, uint32_t ip, uint16_t port);
+   int socket_listen(int s, uint32_t *localip, uint16_t *localport);
+#endif