1 files changed, 117 insertions, 0 deletions
diff --git a/pgm4/inet_dgrams.d/fancy_recv_udp.c b/pgm4/inet_dgrams.d/fancy_recv_udp.c
new file mode 100644
index 0000000..bb4c20a
--- /dev/null
+++ b/pgm4/inet_dgrams.d/fancy_recv_udp.c
@@ -0,0 +1,117 @@
+/*********************************************************************\
+* 		       FANCY_RECV_UDP.C				      *
+* Test of UDP/IP. Receive datagrams on internet socket bound to port  *
+* 0x3333 on the local host.					      *
+* 								      *
+* To use:							      *
+* 	1) On the appropriate host, invoke this code by		      *
+* 	   "fancy_recv_udp&".					      *
+* 	2) Invoke send_udp as many times as desired on the	      *
+* 	   remote host.						      *
+* 								      *
+* Phil Kearns							      *
+* April 11, 1987						      *
+* 								      *
+* Modified: April 10, 1992                                            *
+*      responds to input (CR) on stdin by cleanly shutting down       *
+*      also shuts down if no datagrams for a minute                   *
+\*********************************************************************/
+
+#include	<signal.h>
+#include	<errno.h>
+#include	<string.h>
+#include	<stdio.h>
+#include	<sys/socket.h>
+#include	<netinet/in.h>
+#include	<netdb.h>
+#include        <arpa/inet.h>
+#include        <stdlib.h>
+
+void printsin(struct sockaddr_in*, char*, char*);
+
+int main()
+{
+  int	socket_fd, cc, hits, ecode;
+  socklen_t fsize;
+  fd_set mask;
+  struct timeval timeout;
+  struct sockaddr_in	*s_in, from;
+  struct addrinfo hints, *addrlist;
+    
+  struct {
+    char    head;
+    u_long  body;
+    char    tail;
+  } msg;
+
+  memset(&hints, 0, sizeof(hints));
+  hints.ai_family = AF_INET; hints.ai_socktype = SOCK_DGRAM;
+  hints.ai_flags = AI_NUMERICSERV | AI_PASSIVE; hints.ai_protocol = 0;
+  hints.ai_canonname = NULL; hints.ai_addr = NULL;
+  hints.ai_next = NULL;
+
+  ecode = getaddrinfo(NULL, "13107", &hints, &addrlist);
+  if (ecode != 0) {
+    fprintf(stderr, "getaddrinfo: %s\n", gai_strerror(ecode));
+    exit(1);
+  }
+
+  s_in = (struct sockaddr_in *) addrlist->ai_addr;
+
+  printsin(s_in, "FANCY_RECV_UDP", "Local socket is:"); fflush(stdout);
+
+
+  socket_fd = socket (addrlist->ai_family, addrlist->ai_socktype, 0);
+  if (socket_fd < 0) {
+    perror ("fancy_recv_udp:socket");
+    exit (1);
+  }
+
+/*
+   bind port 0x3333 on the current host to the socket accessed through
+   socket_fd. If port in use, die.
+*/
+  if (bind(socket_fd, (struct sockaddr *)s_in, sizeof(struct sockaddr_in)) < 0) {
+    perror("fancy_recv_udp:bind");
+    exit(1);
+  }
+
+  for(;;) {
+    fsize = sizeof(from);
+/* Here's the new stuff. Hang a select on the file descriptors 0 (stdin)
+   and socket_fd looking to see if either descriptor is able to be read.
+   If it's stdin, shut down. If it's socket_fd, proceed as normal. If
+   Nothing happens for a minute, shut down also.
+*/
+    FD_ZERO(&mask);
+    FD_SET(0,&mask);
+    FD_SET(socket_fd,&mask);
+    timeout.tv_sec = 60;
+    timeout.tv_usec = 0;
+    if ((hits = select(socket_fd+1, &mask, (fd_set *)0, (fd_set *)0,
+                           &timeout)) < 0) {
+      perror("fancy_recv_udp:select");
+      exit(1);
+    }
+    if ( (hits==0) || ((hits>0) && (FD_ISSET(0,&mask))) ) {
+      printf("Shutting down\n");
+      exit(0);
+    }
+    cc = recvfrom(socket_fd,&msg,sizeof(msg),0,(struct sockaddr *)&from,&fsize);
+    if (cc < 0) perror("recv_udp:recvfrom");
+    printsin( &from, "recv_udp: ", "Packet from:");
+    printf("Got data ::%c%u%c\n",msg.head,ntohl(msg.body),msg.tail);
+    fflush(stdout);
+  }
+  exit(0);
+}
+
+void printsin(struct sockaddr_in *sin, char *m1, char *m2 )
+{
+  char fromip[INET_ADDRSTRLEN];
+
+  printf ("%s %s:\n", m1, m2);
+  printf ("  family %d, addr %s, port %d\n", sin -> sin_family,
+	    inet_ntop(AF_INET, &(sin->sin_addr.s_addr), fromip, sizeof(fromip)),
+            ntohs((unsigned short)(sin -> sin_port)));
+}