add: relay/piface support

helpers/bind_server.c

@@ -0,0 +1,51 @@
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <netdb.h>
+#include <sys/socket.h>
+#include <errno.h>
+
+#include <logger.h>
+#include <helpers.h>
+
+int
+helper_bind_tcp_server(char* addr, uint16_t port, int max_client_backlog)
+{
+    char port_str[6];
+    sprintf(port_str, "%d", port);
+
+    struct addrinfo hints, *res;
+    int fd;
+    int status;
+
+    memset(&hints, 0, sizeof hints);
+    hints.ai_family = AF_UNSPEC;
+    hints.ai_socktype = SOCK_STREAM;
+    hints.ai_flags = AI_PASSIVE;
+
+    if ((status = getaddrinfo(addr, port_str, &hints, &res)) != 0)
+    {
+        LOG_ERROR("getaddrinfo: %s", gai_strerror(status));
+        return -1;
+    }
+
+    fd = socket(res->ai_family, res->ai_socktype, res->ai_protocol);
+
+    if ((status = bind(fd, res->ai_addr, res->ai_addrlen)) == -1)
+    {
+        LOG_ERROR("error binding socket: %s", strerror(errno));
+        freeaddrinfo(res);
+        return -1;
+    }
+
+    if ((status = listen(fd, max_client_backlog)) == -1)
+    {
+        LOG_ERROR("error setting up listener: %s", strerror(errno));
+        freeaddrinfo(res);
+        return -1;
+    }
+
+    freeaddrinfo(res);
+
+    return fd;
+}

helpers/connect_server.c

@@ -5,33 +5,35 @@
 #include <sys/socket.h>
 
 #include <logger.h>
-#include <helper.h>
+#include <helpers.h>
 
 int
-helper_connect_server(char* host, char* port)
+helper_connect_tcp_server(char* host, uint16_t port)
 {
-  int s, status;
-  struct addrinfo hints, *res;
-  memset(&hints, 0, sizeof hints);
-  hints.ai_family = AF_INET; //set IP Protocol flag (IPv4 or IPv6 - we don't care)
-  hints.ai_socktype = SOCK_STREAM; //set socket flag
+    char port_str[6];
+    sprintf(port_str, "%d", port);
 
-  if ((status = getaddrinfo(host, port, &hints, &res)) != 0) { //getaddrinfo() will evaluate the given address, using the hints-flags and port, and return an IP address and other server infos
-      fprintf(stderr, "getaddrinfo: %s\n", gai_strerror(status));
-      exit(EXIT_FAILURE);
-  }
+    int s, status;
+    struct addrinfo hints, *res;
+    memset(&hints, 0, sizeof hints);
+    hints.ai_family = AF_INET; //set IP Protocol flag (IPv4 or IPv6 - we don't care)
+    hints.ai_socktype = SOCK_STREAM; //set socket flag
 
-  //res got filled out by getaddrinfo() for us
-  s = socket(res->ai_family, res->ai_socktype, res->ai_protocol); //creating Socket
+    if ((status = getaddrinfo(host, port_str, &hints, &res)) != 0) { //getaddrinfo() will evaluate the given address, using the hints-flags and port, and return an IP address and other server infos
+        LOG_ERROR("getaddrinfo: %s\n", gai_strerror(status));
+        return -1;
+    }
 
-  if ((status = connect(s, res->ai_addr, res->ai_addrlen)) != 0) {
-      fprintf(stderr, "Keine Verbindung mit dem Netzwerk möglich.\n");
-      freeaddrinfo(res);
-      exit(EXIT_FAILURE);
-  }
+    //res got filled out by getaddrinfo() for us
+    s = socket(res->ai_family, res->ai_socktype, res->ai_protocol); //creating Socket
 
-  freeaddrinfo(res);
+    if ((status = connect(s, res->ai_addr, res->ai_addrlen)) != 0) {
+        LOG_ERROR("connect() failed");
+        freeaddrinfo(res);
+        return -1;
+    }
 
-  return s;
+    freeaddrinfo(res);
+
+    return s;
 }
-

helpers/get_port.c

@@ -0,0 +1,24 @@
+#include <sys/socket.h>
+#include <arpa/inet.h>
+#include <stdint.h>
+#include <errno.h>
+#include <string.h>
+
+#include <helpers.h>
+#include <logger.h>
+
+uint16_t
+helper_get_port(int sock)
+{
+    struct sockaddr_in sin;
+    socklen_t len = sizeof(sin);
+    if (getsockname(sock, (struct sockaddr *)&sin, &len) == -1)
+    {
+        LOG_ERROR("could not get socket name for port: %s", strerror(errno));
+        return 0;
+    }
+    else
+    {
+        return ntohs(sin.sin_port);
+    }
+}

helpers/open_discovery_socket.c

@@ -0,0 +1,57 @@
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <netdb.h>
+#include <sys/socket.h>
+
+#include <logger.h>
+#include <helpers.h>
+
+int
+helper_open_discovery_socket(uint16_t discovery_port)
+{
+    struct addrinfo hints, *res;
+    int fd, status;
+
+    memset(&hints, 0, sizeof hints);
+    hints.ai_family = AF_INET; // use ipv4
+    hints.ai_socktype = SOCK_DGRAM; //set socket flag
+    hints.ai_flags = AI_PASSIVE; // get my IP
+
+    char discovery_port_str[6];
+    sprintf(discovery_port_str, "%u", discovery_port);
+
+    //get connection info for our computer
+    if ((status = getaddrinfo(NULL, discovery_port_str, &hints, &res)) != 0)
+    {
+        LOG_FATAL("getaddrinfo: %s", gai_strerror(status));
+        freeaddrinfo(res);
+        exit(EXIT_FAILURE);
+    }
+
+    //creating socket
+    fd = socket(res->ai_family, res->ai_socktype, res->ai_protocol);
+    int yes = 1;
+
+    // lose the pesky "Address already in use" error message
+    if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(yes)) == -1)
+    {
+        LOG_FATAL("setsockopt: %s", strerror(errno));
+        freeaddrinfo(res);
+        exit(EXIT_FAILURE);
+    }
+
+    if (bind(fd, res->ai_addr, res->ai_addrlen) == -1)
+    {
+        LOG_FATAL("bind: %s", strerror(errno));
+        freeaddrinfo(res);
+        exit(EXIT_FAILURE);
+    }
+
+    freeaddrinfo(res);
+
+    LOG_INFO("opened discovery socket on port %u", discovery_port);
+
+    return fd;
+}