1/*
2 * Copyright 2008-2010, Haiku, Inc. All Rights Reserved.
3 * Distributed under the terms of the MIT License.
4 *
5 * Authors:
6 *		Yin Qiu
7 */
8
9
10#include <errno.h>
11#include <netdb.h>
12#include <netinet/in.h>
13#include <stdio.h>
14#include <stdlib.h>
15#include <string.h>
16#include <sys/socket.h>
17#include <unistd.h>
18
19
20#define MAX_LENGTH 4096
21
22
23extern const char* __progname;
24
25
26int
27main(int argc, char** argv)
28{
29	if (argc < 2) {
30		fprintf(stderr, "Usage: %s <host> [<port>]\n"
31			"Sends a UDP datagram to the specified target.\n"
32			"<port> defaults to 9999.\n", __progname);
33		return 1;
34	}
35
36	struct hostent* host = gethostbyname(argv[1]);
37	if (host == NULL) {
38		perror("gethostbyname");
39		return 1;
40	}
41
42	uint16_t port = 9999;
43	if (argc > 2)
44		port = atol(argv[2]);
45
46	struct sockaddr_in serverAddr;
47	memset(&serverAddr, 0, sizeof(struct sockaddr_in));
48	serverAddr.sin_family = AF_INET;
49	serverAddr.sin_port = htons(port);
50	serverAddr.sin_addr = *((struct in_addr*)host->h_addr);
51
52	int sockfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
53	// We need to call connect() to receive async ICMP errors
54	if (connect(sockfd, (struct sockaddr*)&serverAddr,
55			sizeof(struct sockaddr_in)) < 0) {
56		fprintf(stderr, "Calling connect() on UDP socket failed: %s\n",
57			strerror(errno));
58		return 1;
59	}
60
61	const char* string = "Hello";
62	ssize_t bytes = write(sockfd, string, strlen(string));
63	if (bytes < 0) {
64		fprintf(stderr, "UDP send failed: %s\n", strerror(errno));
65		return 1;
66	}
67
68	printf("%zd bytes sent to remote server.\n", bytes);
69
70	char buffer[MAX_LENGTH];
71	bytes = read(sockfd, buffer, MAX_LENGTH);
72	if (bytes > 0) {
73		printf("Received %zd bytes from remote host\n", bytes);
74		printf("%s\n", buffer);
75	} else {
76		// We are expecting this
77		printf("Error: %s\n", strerror(errno));
78	}
79	close(sockfd);
80	printf("Socket closed.\n");
81
82	return 0;
83}
84