a bit cosmetic

Author: alexander-naumov

sockets/RAW/icmp.c

@@ -1,3 +1,9 @@
+/* icmp.c: simple ICMP request implementaion
+ *
+ * Alexander Naumov <posix.ru@gmail.com>
+ *
+ */
+
 #include <error.h>
 #include <fcntl.h>
 #include <unistd.h>
@@ -20,93 +26,90 @@ struct protoent *proto=NULL;
 
 struct packet
 {
-    struct icmphdr hdr;
-    char msg[PACKETSIZE-sizeof(struct icmphdr)];
+	struct icmphdr hdr;
+	char msg[PACKETSIZE-sizeof(struct icmphdr)];
 };
 
-
 void usage()
 {
-    printf("USAGE:\t  ccns <IP_address>\n");
-    exit(1);
+	printf("USAGE:\ticmp <IP_address>\n");
+	exit(1);
 }
 
-
 unsigned short checksum(void *b, int len)
 {
-    unsigned short *buf = b;
-    unsigned int sum=0;
-    unsigned short result;
-
-    for(sum = 0; len > 1; len -= 2)
-        sum += *buf++;
-    if(len == 1)
-        sum += *(unsigned char*)buf;
-    sum = (sum >> 16) + (sum & 0xFFFF);
-    sum += (sum >> 16);
-    result = ~sum;
-    return result;
+	unsigned short *buf = b;
+	unsigned int sum=0;
+	unsigned short result;
+
+	for(sum = 0; len > 1; len -= 2)
+		sum += *buf++;
+	if(len == 1)
+		sum += *(unsigned char*)buf;
+	sum = (sum >> 16) + (sum & 0xFFFF);
+	sum += (sum >> 16);
+	result = ~sum;
+	return result;
 }
 
 int ping(char *host)
 {
-    struct hostent *hname;
-    struct sockaddr_in addr;
+	struct hostent *hname;
+	struct sockaddr_in addr;
 
-    proto = getprotobyname("ICMP");
-    hname = gethostbyname(host);
+	proto = getprotobyname("ICMP");
+	hname = gethostbyname(host);
 
-    bzero(&addr, sizeof(addr));
+	bzero(&addr, sizeof(addr));
 
-    addr.sin_family = hname->h_addrtype;
-    addr.sin_port = 0;
-    addr.sin_addr.s_addr = *(long*)hname->h_addr;
+	addr.sin_family = hname->h_addrtype;
+	addr.sin_port = 0;
+	addr.sin_addr.s_addr = *(long*)hname->h_addr;
 
-    const int val=255;
-    int i, sd, cnt=0;
-    struct packet pckt;
-    struct sockaddr_in r_addr;
+	const int val=255;
+	int i, sd, cnt=0;
+	struct packet pckt;
+	struct sockaddr_in r_addr;
 
-    sd = socket(AF_INET, SOCK_RAW, IPPROTO_ICMP);
-    if (sd < 0) {
-        perror("socket");
-        exit(1);
-    }
+	sd = socket(AF_INET, SOCK_RAW, IPPROTO_ICMP);
+	if (sd < 0) {
+		perror("socket");
+		exit(1);
+	}
 
-    if (setsockopt(sd, SOL_IP, IP_TTL, &val, sizeof(val)) != 0)
-        perror("Set TTL option");
+	if (setsockopt(sd, SOL_IP, IP_TTL, &val, sizeof(val)) != 0)
+		perror("Set TTL option");
 
-    if (fcntl(sd, F_SETFL, O_NONBLOCK) != 0 )
-        perror("Request nonblocking I/O");
+	if (fcntl(sd, F_SETFL, O_NONBLOCK) != 0 )
+		perror("Request nonblocking I/O");
 
-    int count, icmp = 0;
-    for(count = 0; count < 4; count++) {
-        int len = sizeof(r_addr);
+	int count, icmp = 0;
+	for(count = 0; count < 4; count++) {
+		int len = sizeof(r_addr);
 
-        bzero(&pckt, sizeof(pckt));
-        pckt.hdr.type = ICMP_ECHO;
-        pckt.hdr.un.echo.id = pid;
+		bzero(&pckt, sizeof(pckt));
+		pckt.hdr.type = ICMP_ECHO;
+		pckt.hdr.un.echo.id = pid;
 
-        for(i = 0; i < sizeof(pckt.msg)-1; i++)
-            pckt.msg[i] = i+'0';
+		for(i = 0; i < sizeof(pckt.msg)-1; i++)
+			pckt.msg[i] = i+'0';
 
-        pckt.msg[i] = 0;
-        pckt.hdr.un.echo.sequence = cnt++;
-        pckt.hdr.checksum = checksum(&pckt, sizeof(pckt));
+		pckt.msg[i] = 0;
+		pckt.hdr.un.echo.sequence = cnt++;
+		pckt.hdr.checksum = checksum(&pckt, sizeof(pckt));
 
 		printf("Msg #%d\n", cnt);
-        if (sendto(sd, &pckt, sizeof(pckt), 0, (struct sockaddr*)&addr, sizeof(addr)) <= 0 )
-            perror("sendto");
+		if (sendto(sd, &pckt, sizeof(pckt), 0, (struct sockaddr*)&addr, sizeof(addr)) <= 0 )
+			perror("sendto");
 
-        sleep(1);
+		sleep(1);
 
-        if (recvfrom(sd, &pckt, sizeof(pckt), 0, (struct sockaddr*)&r_addr, &len) > 0 ) {
-            icmp++;
+		if (recvfrom(sd, &pckt, sizeof(pckt), 0, (struct sockaddr*)&r_addr, &len) > 0 ) {
+			icmp++;
 			printf("***Got message!***\n");
-            if (icmp > 1)
-                return icmp;
-        }
-
+			if (icmp > 1)
+				return icmp;
+		}
 	}
     return icmp;
 }
@@ -120,7 +123,7 @@ int main(int argc, char *argv[])
 		printf("PING\t\tOK\n");
     else
 		printf("PING\t\tNO_ANSWER\n");
-    
+
 	return 0;
 }