tip.c

Linux平台怎么建立socket服务器端和client客户端

/*****************************************************************************/

/*
 *	tip.c -- simple tip/cu program.
 *
 *	(C) Copyright 1999, Greg Ungerer ([e-mail]).
 * 	(C) Copyright 2000, Lineo Inc. (www.lineo.com) 
 *
 *	Modified 5 May 2000, Rick Stevenson.
 *		Added -f option to pass XON/XOFF characters through
 *		to remote end.
 */

/*****************************************************************************/

#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <fcntl.h>
#include <getopt.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/termios.h>
#include <sys/time.h>

#ifndef EMBED
#include <sys/select.h>
#endif

/*****************************************************************************/

char *version = "1.0.0";

/*****************************************************************************/

/*
 *	Define some parity flags, internal use only.
 */
#define	PARITY_NONE	0
#define	PARITY_EVEN	1
#define	PARITY_ODD	2

/*
 *	Default port settings.
 */
int		clocal = 0;
int		hardware = 0;
int		software = 0;
int		passflow = 0;
int		parity = PARITY_NONE;
int		databits = 8;
unsigned int	baud = 9600;

char		*devname;
int		gotdevice = 0;

/*
 *	Working termios settings.
 */
struct termios	savetio;


/*
 *	Temporary buffer to use when working.
 */
unsigned char	buf[512];

/*****************************************************************************/

/*
 *	Baud rate table for baud rate conversions.
 */
typedef struct baudmap {
	unsigned int	baud;
	unsigned int	flag;
} baudmap_t;


struct baudmap	baudtable[] = {
	{ 0, B0 },
	{ 50, B50 },
	{ 75, B75 },
	{ 110, B110 },
	{ 134, B134 },
	{ 150, B150 },
	{ 200, B200 },
	{ 300, B300 },
	{ 600, B600 },
	{ 1200, B1200 },
	{ 1800, B1800 },
	{ 2400, B2400 },
	{ 4800, B4800 },
	{ 9600, B9600 },
	{ 19200, B19200 },
	{ 38400, B38400 },
	{ 57600, B57600 },
	{ 115200, B115200 },
	{ 230400, B230400 },
	{ 460800, B460800 }
};

#define	NRBAUDS		(sizeof(baudtable) / sizeof(struct baudmap))


/*****************************************************************************/
/*
 *	Verify that the supplied baud rate is valid.
 */

int baud2flag(unsigned int speed)
{
	int	i;

	for (i = 0; (i < NRBAUDS); i++) {
		if (speed == baudtable[i].baud)
			return(baudtable[i].flag);
	}
	return(-1);
}

/*****************************************************************************/

void restorelocaltermios()
{
	if (tcsetattr(1, TCSAFLUSH, &savetio) < 0) {
		fprintf(stderr, "ERROR: ioctl(TCSETA) failed, errno=%d\n",
			errno);
		exit(0);
	}
}

/*****************************************************************************/

void savelocaltermios()
{
	if (tcgetattr(1, &savetio) < 0) {
		fprintf(stderr, "ERROR: ioctl(TCGETA) failed, errno=%d\n",
			errno);
		exit(0);
	}
}

/*****************************************************************************/

/*
 *	Set local port to raw mode, no input mappings.
 */

int setlocaltermios()
{
	struct termios	tio;

	if (tcgetattr(1, &tio) < 0) {
		fprintf(stderr, "ERROR: ioctl(TCGETA) failed, errno=%d\n",
			errno);
		exit(1);
	}

	if (passflow)
		tio.c_iflag &= ~(ICRNL|IXON);
	else
		tio.c_iflag &= ~ICRNL;
	tio.c_lflag = 0;
	tio.c_cc[VMIN] = 1;
	tio.c_cc[VTIME] = 0;

	if (tcsetattr(1, TCSAFLUSH, &tio) < 0) {
		fprintf(stderr, "ERROR: ioctl(TCSETA) failed, errno=%d\n",
			errno);
		exit(1);
	}
	return(0);
}

/*****************************************************************************/

/*
 *	Set up remote (connect) port termio settings according to
 *	user specification.
 */

int setremotetermios(int fd)
{
	struct termios	tio;

	memset(&tio, 0, sizeof(tio));
	tio.c_cflag = CREAD | HUPCL | baud2flag(baud);

	if (clocal)
		tio.c_cflag |= CLOCAL;

	switch (parity) {
	case PARITY_ODD:	tio.c_cflag |= PARENB | PARODD; break;
	case PARITY_EVEN:	tio.c_cflag |= PARENB; break;
	default:		break;
	}

	tio.c_cflag |= ((databits == 7) ? CS7 : CS8);

	if (software)
		tio.c_iflag |= IXON | IXOFF;
	if (hardware)
		tio.c_cflag |= CRTSCTS;

	tio.c_cc[VMIN] = 1;
	tio.c_cc[VTIME] = 0;

	if (tcsetattr(fd, TCSAFLUSH, &tio) < 0) {
		fprintf(stderr, "ERROR: ioctl(TCSETS) failed\n");
		exit(1);
	}
	return(0);
}

/*****************************************************************************/

/*
 *	Do the connection session. Pass data between local and remote
 *	ports.
 */

int loopit(int fd)
{
	fd_set	infds;
	int	maxfd, n;
	int	partialescape = 0;

	maxfd = fd + 1;

	for (;;) {
		FD_ZERO(&infds);
		FD_SET(1, &infds);
		FD_SET(fd, &infds);

		if (select(maxfd, &infds, NULL, NULL, NULL) < 0) {
			fprintf(stderr, "ERROR: select() failed, errno=%d\n",
				errno);
			exit(1);
		}

		if (FD_ISSET(fd, &infds)) {
			if ((n = read(fd, buf, sizeof(buf))) < 0) {
				fprintf(stderr, "ERROR: read(fd=%d) failed, "
					"errno=%d\n", fd, errno);
				exit(1);
			}
			if (n == 0)
				break;
			if (write(1, buf, n) < 0) {
				fprintf(stderr, "ERROR: write(fd=%d) failed, "
					"errno=%d\n", 1, errno);
				exit(1);
			}
		}

		if (FD_ISSET(1, &infds)) {
			if ((n = read(1, buf, sizeof(buf))) < 0) {
				fprintf(stderr, "ERROR: read(fd=%d) failed, "
					"errno=%d\n", 1, errno);
				exit(1);
			}

			if (n == 0)
				break;
			if ((n == 1) && (buf[0] == 0x1d))
				break;
			if ((n == 1) && (buf[0] == 0x1))
				break;
			if (partialescape) {
				if (buf[0] == '.')
					break;
				write(fd, "~", 1);
			}
			partialescape = ((n == 1) && (buf[0] == '~')) ? 1 : 0;

			if (write(fd, buf, n) < 0) {
				fprintf(stderr, "ERROR: write(fd=%d) failed, "
					"errno=%d\n", fd, errno);
				exit(1);
			}
		}
	}
}

/*****************************************************************************/

void usage(FILE *fp, int rc)
{
	fprintf(fp, "Usage: tip [-h?eonxrc78] [-s speed] [-l device] "
		"[device]\n\n");
	fprintf(fp, "        -h?       this help\n");
	fprintf(fp, "        -7        7 data bits\n");
	fprintf(fp, "        -8        8 data bits (default)\n");
	fprintf(fp, "        -e        even parity\n");
	fprintf(fp, "        -o        odd parity\n");
	fprintf(fp, "        -n        no parity (default)\n");
	fprintf(fp, "        -s        baud rate (default 9600)\n");
	fprintf(fp, "        -c        use clocal mode (no disconnect)\n");
	fprintf(fp, "        -l        device to use\n");
	fprintf(fp, "        -x        use software flow (xon/xoff)\n");
	fprintf(fp, "        -r        use hardware flow (rts/cts)\n");
	fprintf(fp, "        -f        pass xon/xoff flow control to remote\n");
	exit(rc);
}

/*****************************************************************************/

int main(int argc, char *argv[])
{
	int	fd, c;

	gotdevice = 0;

	while ((c = getopt(argc, argv, "eonxrcf78h?s:l:")) > 0) {
		switch (c) {
		case 'v':
			printf("%s: version %s\n", argv[0], version);
			exit(0);
		case '7':
			databits = 7;
			break;
		case '8':
			databits = 8;
			break;
		case 'r':
			hardware++;
			break;
		case 'x':
			software++;
			break;
		case 'f':
			passflow++;
			break;
		case 'o':
			parity = PARITY_ODD;
			break;
		case 'e':
			parity = PARITY_EVEN;
			break;
		case 'n':
			parity = PARITY_NONE;
			break;
		case 's':
			baud = atoi(optarg);
			if (baud2flag(baud) < 0) {
				fprintf(stderr,
					"ERROR: baud speed specified %d\n",
					baud);
				exit(1);
			}
			break;
		case 'c':
			clocal++;
			break;
		case 'l':
			gotdevice++;
			devname = optarg;
			break;
		case 'h':
		case '?':
			usage(stdout, 0);
			break;
		default:
			fprintf(stderr, "ERROR: unkown option '%c'\n", c);
			usage(stderr, 1);
			break;
		}
	}

	if ((optind < argc) && (gotdevice == 0)) {
		gotdevice++;
		devname = argv[optind++];
	}

	if (gotdevice == 0) {
		fprintf(stderr, "ERROR: no device specified\n");
		usage(stderr, 1);
	}
	if (optind < argc) {
		fprintf(stderr, "ERROR: too many arguments\n");
		usage(stderr, 1);
	}

	/*
	 *	Check device is real, and open it.
	 */
	if ((fd = open(devname, (O_RDWR | O_NDELAY))) < 0) {
		fprintf(stderr, "ERROR: failed to open %s, errno=%d\n",
			devname, errno);
		exit(0);
	}

	setremotetermios(fd);
	savelocaltermios();
	setlocaltermios();

	printf("Connected.\n");
	loopit(fd);

	restorelocaltermios();
	close(fd);
	printf("Disconnected.\n");
	exit(0);
}

/*****************************************************************************/