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/*
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 *  fndsockserver.c
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 *  Copyright 2006 Ramon de Carvalho Valle <[email protected]>
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 *
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 *  This program is free software; you can redistribute it and/or modify
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 *  it under the terms of the GNU General Public License as published by
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 *  the Free Software Foundation; either version 2 of the License, or
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 *  (at your option) any later version.
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 *
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 *  This program is distributed in the hope that it will be useful,
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 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
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 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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 *  GNU General Public License for more details.
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 *
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 *  You should have received a copy of the GNU General Public License
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 *  along with this program; if not, write to the Free Software
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 *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
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 *
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 */
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <sys/types.h>
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#include <sys/socket.h>
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#include <arpa/inet.h>
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#include <netdb.h>
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#include <sys/select.h>
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#include <unistd.h>
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#include <errno.h>
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#define BACKLOG 5
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int
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hexdump(char *buf, int len)
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{
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	int i, j;
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	for (i=0; i<len; i++) {
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		for (j=0; j<16; j++) {
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			if (i+j >= len)
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				printf("%3s","");
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			else
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				printf("%02x ", (unsigned char)buf[i+j]);
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		}
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		printf("%3s","");
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		for (j=0; j<16; j++) {
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			if (i+j >= len)
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				printf("%1s","");
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			else
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				if (buf[i+j]>'\x1f' && buf[i+j]<'\x7f')
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					printf("%c", buf[i+j]);
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				else
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					printf(".");
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		}
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		i += 15;
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		printf("\n");
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	}
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	return 0;
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}
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int
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main(int argc, char **argv)
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{
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	char *addr = "0.0.0.0";
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	int port = 1234;
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	int c, s;
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	int debug = 0, verbose = 0;
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	struct sockaddr_in sin;
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	struct hostent *he;
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	while ((c = getopt(argc, argv, "a:dp:v")) != -1) {
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		switch (c) {
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		case 'a':
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			addr = optarg;
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			break;
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		case 'd':
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			debug = 1;
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			break;
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		case 'p':
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			port = atoi(optarg);
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			break;
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		case 'v':
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			verbose = 1;
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		}
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	}
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	if ((s = socket(AF_INET, SOCK_STREAM, 0)) == -1) {
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		perror("socket");
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		exit(EXIT_FAILURE);
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	}
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	memset(&sin, 0, sizeof(sin));
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	sin.sin_family = AF_INET;
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	sin.sin_port = htons(port);
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	if ((sin.sin_addr.s_addr = inet_addr(addr)) == -1) {
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		if ((he = gethostbyname(addr)) == NULL) {
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			errno = EADDRNOTAVAIL;
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			perror("gethostbyname");
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			exit(EXIT_FAILURE);
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		}
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		memcpy(&sin.sin_addr.s_addr, he->h_addr, 4);
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	}
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	if (bind(s, (struct sockaddr *)&sin, sizeof(sin)) == -1) {
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		perror("bind");
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		exit(EXIT_FAILURE);
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	}
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	if (listen(s, BACKLOG) == -1) {
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		perror("listen");
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		exit(EXIT_FAILURE);
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	}
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	if (debug || verbose)
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		printf("listening on %s:%d\n", addr, port);
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	while (1) {
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		int tmp;
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		struct sockaddr_in sin;
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		socklen_t sin_len = sizeof(sin);
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		if((tmp = accept(s, (struct sockaddr *)&sin, &sin_len)) == -1) {
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			perror("accept");
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			exit(EXIT_FAILURE);
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		}
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		if (debug || verbose)
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			printf("accepted connection from %s:%d\n", inet_ntoa(sin.sin_addr),
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			ntohs(sin.sin_port));
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		if (!fork()) {
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			int count;
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			char buf[1024];
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			count = recv(tmp, buf, sizeof(buf), 0);
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			if (debug)
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				hexdump(buf, count);
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			if (debug || verbose)
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				printf("%d bytes received\n", count);
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			sleep(2);
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#if defined(_AIX) || (defined(__linux__) && defined(__powerpc64__))
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			{
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				/* fake function descriptor */
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				unsigned long fdesc[2] = {(unsigned long)buf, 0};
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				(*(void (*)())fdesc)();
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			}
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#else
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			(*(void (*)())buf)();
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#endif
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			exit(EXIT_SUCCESS);
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		}
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	}
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	exit(EXIT_SUCCESS);
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}
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