--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/intercom/udp.cpp	Fri Jun 25 09:57:52 2010 +0200
@@ -0,0 +1,157 @@
+/* udp.cpp
+ *
+ * Copyright (C) DFS Deutsche Flugsicherung (2004, 2005). 
+ * All Rights Reserved.
+ *
+ * UDP functions for IPv4
+ * Multicast Doc: /usr/share/doc/howto/en/html/Multicast-HOWTO.html
+ *
+ * Version 0.2
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+ /* Socket io */
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <netdb.h>
+#include <sys/time.h>
+#include <unistd.h>
+#include <sys/errno.h>
+#include <assert.h>
+
+#include "udp.h"
+#include "intercomd.h"
+
+int UDP_recv_init(int port)
+/* starte UDP LAN Empfang. Programm-Exit bei Fehler! */
+/* return: Filedescriptor fuer Empfang */
+/* in port: UDP Port Nummer */
+{
+  int fd;
+  struct sockaddr_in sock;
+  int local_flag;
+  socklen_t local_flagsize;
+
+  /* init UDP local1 */
+  fd = socket(AF_INET, SOCK_DGRAM, 0);
+  if (fd < 0) {
+    fprintf(stderr, "if_recv_init(): socket() failed\n");
+    exit(1);
+  }
+
+  memset((char *) &sock, 0, sizeof(sock));
+  sock.sin_family = AF_INET;
+  sock.sin_addr.s_addr = htonl(INADDR_ANY);
+  sock.sin_port = htons(port);
+  if (bind(fd, (struct sockaddr *) &sock, sizeof(sock)) < 0) {
+    fprintf(stderr, "if_recv_init(): bind() failed\n");
+    exit(2);
+  }
+  local_flagsize = sizeof(int);
+  if (getsockopt(fd, SOL_SOCKET, SO_RCVBUF, (char *) &local_flag,
+      &local_flagsize) < 0) {
+    fprintf(stderr, "if_recv_init(): getsockopt() failed\n");
+    exit(3);
+  }
+  /* printf("SO_RCVBUF=%d\n", local_flag); */
+
+  /* printf("init socket\n"); */
+  return fd;
+}
+
+void UDP::send_init(char *foreign_name, int foreign_port, int local_fd_)
+/* Starte Versand von UDP Meldungen auf LAN */
+/* in foreign_name: IP-Adresse auf die gesendet wird */
+/* in foreign_port: UDP-Port auf den gesendet wird */
+{
+  struct hostent *foreign_host;
+  int local_flag;
+  socklen_t local_flagsize;
+
+  local_fd = local_fd_;
+
+  /* turn on broadcast */
+  local_flagsize = sizeof(int);
+  if (getsockopt(local_fd, SOL_SOCKET, SO_BROADCAST,
+      (char *) &local_flag, &local_flagsize) < 0) {
+    fprintf(stderr, "udp_send_init(): getsockopt() failed\n");
+    exit(3);
+  }
+  if (local_flag == 0) {
+    local_flag = 1;
+    setsockopt(local_fd, SOL_SOCKET, SO_BROADCAST, (char *) &local_flag,
+      sizeof(int));
+    local_flagsize = sizeof(int);
+    if (getsockopt(local_fd, SOL_SOCKET, SO_BROADCAST,
+        (char *) &local_flag, &local_flagsize) < 0) {
+      fprintf(stderr, "udp_send_init() SO_BROADCAST failed\n");
+      exit(3);
+    }
+  }
+
+  /* init foreign part */
+  memset((char *) &foreign_sock, 0, sizeof(foreign_sock));
+
+  foreign_host = gethostbyname(foreign_name);
+  if (foreign_host == NULL || foreign_host->h_length == 0) {
+    fprintf(stderr, "udp_send_init(): gethostbyname() failed");
+    exit(1);
+  }
+  memcpy(&foreign_sock.sin_addr.s_addr, foreign_host->h_addr_list[0],
+    foreign_host->h_length);
+  foreign_sock.sin_family = AF_INET;
+  foreign_sock.sin_port = htons(foreign_port);
+
+
+  in_addr_t to_ip = ntohl(foreign_sock.sin_addr.s_addr);
+  char s[20];
+  print_gui("c %s\n", iptoa(s, to_ip));
+}
+
+void UDP::send(char *buf, int bytes)
+/* Sende UDP Meldung auf LAN */
+/* in buf: Meldung */
+/* in bytes: Laenge der Meldung */
+{
+  int len;
+
+  len = sendto(local_fd,
+    buf, bytes,
+    0, (struct sockaddr *) &foreign_sock, sizeof(foreign_sock));
+  if (len != bytes) {
+    fprintf(stderr, "udp_send(): sendto() foreign failed ret=%d\n",
+      len);
+  }
+}
+
+void UDP::send_close()
+{
+  memset((char *) &foreign_sock, 0, sizeof(foreign_sock));
+}
+
+// IP to ASCII
+char *iptoa(char *buf, in_addr_t ip)
+{
+  int i1 = ip >> 24;
+  int i2 = (ip >> 16) & 0xFF;
+  int i3 = (ip >> 8) & 0xFF;
+  int i4 = ip & 0xFF;
+
+  sprintf(buf, "%d.%d.%d.%d", i1, i2, i3, i4);
+
+  return buf;
+}
+
+// ASCII to IP
+in_addr_t atoip(char *buf)
+{
+  int i1, i2, i3, i4;
+
+  sscanf(buf, "%d.%d.%d.%d", &i1, &i2, &i3, &i4);
+
+  return i1 << 24 | i2 << 16 | i3 << 8 | i4;
+}