Added code to print the target system with each down message.

This allows for multiple cpings to run in the same window in the
background and be able to tell which host missed pings.

Author: horner

README.md

@@ -3,7 +3,7 @@ cping
 
 A cooler version of ping that has a -F threshold in milliseconds option.  With -F specified, only 
 packets that miss the threshold are printed.  Also, if the target host goes down, the duration of the downtime
-is printed in summary.
+is printed in summary.  Also mutiple cpings can be run in the background (ie: ```cping -F 10 host &```) and the output will show which host missed a ping threshold.
 
 ```
 $ cping -F 30 google.com

cping.c

@@ -94,7 +94,7 @@ int maxpacket = sizeof(outpack);
 
 static int broadcast_pings = 0;
 
-static char *pr_addr(__u32);
+char *pr_addr(__u32);
 static void pr_options(unsigned char * cp, int hlen);
 static void pr_iph(struct iphdr *ip);
 static void usage(void) __attribute__((noreturn));

cping_common.c

@@ -60,7 +60,11 @@ int ident;			/* process id to identify our packets */
 
 static int screen_width = INT_MAX;
 
-static int checktimeout(int ours)
+char *pr_addr(__u32);
+
+extern struct sockaddr_in whereto;   /* who to ping */
+
+static int checktimeout(int ours, char *from)
 {
 // DRH---  NOT THREAD SAFE!
 	static int init=0;
@@ -87,14 +91,14 @@ static int checktimeout(int ours)
   	stime+=4;
 
 	if (ours==1) {
-		if (firstline==0) printf("%20.20s System responed to a ping.  Down for %f secs          \n", stime, ret/1000000.0);
+		if (firstline==0) printf("%20.20s System (%s) responed to a ping.  Down for %f secs          \n", stime, from, ret/1000000.0);
 		tmp=tvold;
 	 	tvold=tvnew;
 	 	tvnew=tmp;
 		firstline=1;
 	} else {
 		if ((tvnew->tv_sec - tvold->tv_sec)>2) {
-			printf("%20.20s Missing pings.  Down for %f secs          \r", stime, ret/1000000.0);
+			printf("%20.20s (%s) Missing pings.  Down for %f secs          \r", stime, from, ret/1000000.0);
 			fflush(stdout);
 			if (firstline) {
 				printf("\n");
@@ -651,7 +655,7 @@ void main_loop(int icmp_sock, __u8 *packet, int packlen)
 
 			if (cc < 0) {
 				if (errno == EAGAIN || errno == EINTR) {
-					checktimeout(0);
+					checktimeout(0, pr_addr(whereto.sin_addr.s_addr));
 					break;
 				}
 				if (!receive_error_msg()) {
@@ -683,15 +687,15 @@ void main_loop(int icmp_sock, __u8 *packet, int packlen)
 
 				not_ours = parse_reply(&msg, cc, addrbuf, recv_timep);
 				if (not_ours) {
-					checktimeout(0);
+					checktimeout(0, pr_addr(whereto.sin_addr.s_addr));
 				} else {
-					checktimeout(1);
+					checktimeout(1, pr_addr(whereto.sin_addr.s_addr));
 				}
 			}
 
 			/* See? ... someone runs another ping on this host. */ 
 			if (not_ours) {
-				checktimeout(0);
+				checktimeout(0, pr_addr(whereto.sin_addr.s_addr));
 				install_filter();
 			}