[unix-history] / usr / src / usr.bin / tftp / main.c

/*	main.c	4.2	82/10/08	*/

/*
 * TFTP User Program -- Command Interface.
 */
#include <sys/types.h>
#include <net/in.h>
#include <sys/socket.h>
#include <signal.h>
#include <stdio.h>
#include <errno.h>
#include <setjmp.h>
#include <ctype.h>
#include <netdb.h>

struct	sockaddr_in sin = { AF_INET };
int	f;
int	options;
int	trace;
int	verbose;
int	connected;
char	mode[32];
char	line[200];
int	margc;
char	*margv[20];
char	*prompt = "tftp";
jmp_buf	toplevel;
int	intr();
struct	servent *sp;

int	quit(), help(), setverbose(), settrace(), status();
int	get(), put(), setpeer(), setmode();

#define HELPINDENT (sizeof("connect"))

struct cmd {
	char	*name;
	char	*help;
	int	(*handler)();
};

char	vhelp[] = "toggle verbose mode";
char	thelp[] = "toggle packet tracing";
char	chelp[] = "connect to remote tftp";
char	qhelp[] = "exit tftp";
char	hhelp[] = "print help information";
char	shelp[] = "send file";
char	rhelp[] = "receive file";
char	mhelp[] = "set file transfer mode";
char	sthelp[] = "show current status";

struct cmd cmdtab[] = {
	{ "connect",	chelp,		setpeer },
	{ "mode",	mhelp,		setmode },
	{ "put",	shelp,		put },
	{ "get",	rhelp,		get },
	{ "quit",	qhelp,		quit },
	{ "verbose",	vhelp,		setverbose },
	{ "trace",	thelp,		settrace },
	{ "status",	sthelp,		status },
	{ "?",		hhelp,		help },
	0
};

struct	cmd *getcmd();
char	*tail();
char	*index();
char	*rindex();

main(argc, argv)
	char *argv[];
{
	sp = getservbyname("tftp", "udp");
	if (sp == 0) {
		fprintf(stderr, "tftp: udp/tftp: unknown service\n");
		exit(1);
	}
	sin.sin_port = htons(sp->s_port);
	if (argc > 1 && !strcmp(argv[1], "-d")) {
		options |= SO_DEBUG;
		argc--, argv++;
	}
	f = socket(SOCK_DGRAM, 0, 0, options);
	if (f < 0) {
		perror("socket");
		exit(3);
	}
	strcpy(mode, "netascii");
	if (argc > 1) {
		if (setjmp(toplevel) != 0)
			exit(0);
		setpeer(argc, argv);
	}
	setjmp(toplevel);
	for (;;)
		command(1);
}

char	*hostname;
char	hnamebuf[32];

setpeer(argc, argv)
	int argc;
	char *argv[];
{
	register int c;
	struct hostent *host;

	if (argc < 2) {
		strcpy(line, "Connect ");
		printf("(to) ");
		gets(&line[strlen(line)]);
		makeargv();
		argc = margc;
		argv = margv;
	}
	if (argc > 3) {
		printf("usage: %s host-name [port]\n", argv[0]);
		return;
	}
	host = gethostbyname(argv[1]);
	if (host) {
		bcopy(host->h_addr, &sin.sin_addr, host->h_length);
		hostname = host->h_name;
	} else {
		sin.sin_addr.s_addr = inet_addr(argv[1]);
		if (sin.sin_addr.s_addr == -1) {
			connected = 0;
			printf("%s: unknown host\n", argv[1]);
			return;
		}
		strcpy(hnamebuf, argv[1]);
		hostname = hnamebuf;
	}
	sin.sin_port = sp->s_port;
	if (argc == 3) {
		sin.sin_port = atoi(argv[2]);
		if (sin.sin_port < 0) {
			printf("%s: bad port number\n", argv[2]);
			connected = 0;
			return;
		}
	}
#if vax || pdp11
	sin.sin_port = htons(sin.sin_port);
#endif
	connected = 1;
}

struct	modes {
	char *m_name;
	char *m_mode;
} modes[] = {
	{ "ascii",	"netascii" },
	{ "binary",	"octect" },
	{ "mail",	"mail" },
	{ 0,		0 }
};

setmode(argc, argv)
	char *argv[];
{
	register struct modes *p;

	if (argc > 2) {
		char *sep;

		printf("usage: %s [", argv[0]);
		sep = " ";
		for (p = modes; p->m_name; p++) {
			printf("%s%s", sep, p->m_name);
			if (*sep == ' ')
				sep = " | ";
		}
		printf(" ]\n");
		return;
	}
	if (argc < 2) {
		printf("Using %s mode to transfer files.\n", mode);
		return;
	}
	for (p = modes; p->m_name; p++)
		if (strcmp(argv[1], p->m_name) == 0)
			break;
	if (p->m_name)
		strcpy(mode, p->m_mode);
	else
		printf("%s: unknown mode\n", argv[1]);
}

/*
 * Send file(s).
 */
put(argc, argv)
	char *argv[];
{
	int fd;
	register int n, addr;
	register char *cp, *targ;

	if (argc < 2) {
		strcpy(line, "send ");
		printf("(file) ");
		gets(&line[strlen(line)]);
		makeargv();
		argc = margc;
		argv = margv;
	}
	if (argc < 2) {
		putusage(argv[0]);
		return;
	}
	targ = argv[argc - 1];
	if (index(argv[argc - 1], ':')) {
		char *cp;
		struct hostent *hp;

		for (n = 1; n < argc - 1; n++)
			if (index(argv[n], ':')) {
				putusage(argv[0]);
				return;
			}
		cp = argv[argc - 1];
		targ = index(cp, ':');
		*targ++ = 0;
		hp = gethostbyname(cp);
		if (hp == 0) {
			printf("%s: Unknown host.\n", cp);
			return;
		}
		bcopy(hp->h_addr, &sin.sin_addr, hp->h_length);
		sin.sin_family = hp->h_addrtype;
		connected = 1;
		hostname = hp->h_name;
	}
	if (!connected) {
		printf("No target machine specified.\n");
		return;
	}
	sigset(SIGINT, intr);
	if (argc < 4) {
		cp = argc == 2 ? tail(targ) : argv[1];
		fd = open(cp);
		if (fd < 0) {
			perror(cp);
			return;
		}
		sendfile(fd, targ);
		return;
	}
	cp = index(targ, '\0'); 
	*cp++ = '/';
	for (n = 1; n < argc - 1; n++) {
		strcpy(cp, tail(argv[n]));
		fd = open(argv[n], 0);
		if (fd < 0) {
			perror(argv[n]);
			continue;
		}
		sendfile(fd, targ);
	}
}

putusage(s)
	char *s;
{
	printf("usage: %s file ... host:target, or\n", s);
	printf("       %s file ... target (when already connected)\n", s);
}

/*
 * Receive file(s).
 */
get(argc, argv)
	char *argv[];
{
	int fd;
	register int n, addr;
	register char *cp;
	char *src;

	if (argc < 2) {
		strcpy(line, "get ");
		printf("(files) ");
		gets(&line[strlen(line)]);
		makeargv();
		argc = margc;
		argv = margv;
	}
	if (argc < 2) {
		getusage(argv[0]);
		return;
	}
	if (!connected)
		for (n = 1; n < argc - 1; n++)
			if (index(argv[n], ':') == 0) {
				getusage(argv[0]);
				return;
			}
	sigset(SIGINT, intr);
	for (n = 1; argc == 2 || n < argc - 1; n++) {
		src = index(argv[n], ':');
		if (src == NULL)
			src = argv[n];
		else {
			struct hostent *hp;

			*src++ = 0;
			hp = gethostbyname(argv[n]);
			if (hp == 0) {
				printf("%s: Unknown host.\n", argv[n]);
				continue;
			}
			bcopy(hp->h_addr, &sin.sin_addr, hp->h_length);
			sin.sin_family = hp->h_addrtype;
			connected = 1;
			hostname = hp->h_name;
		}
		if (argc < 4) {
			cp = argc == 3 ? argv[2] : tail(src);
			fd = creat(cp, 0644);
			if (fd < 0) {
				perror(cp);
				return;
			}
			recvfile(fd, src);
			break;
		}
		cp = index(argv[argc - 1], '\0');
		*cp++ = '/';
		strcpy(cp, tail(src));
		fd = creat(src, 0644);
		if (fd < 0) {
			perror(src);
			continue;
		}
		recvfile(fd, src);
	}
}

getusage(s)
{
	printf("usage: %s host:file host:file ... file, or\n", s);
	printf("       %s file file ... file if connected\n", s);
}

status(argc, argv)
	char *argv[];
{
	if (connected)
		printf("Connected to %s.\n", hostname);
	else
		printf("Not connected.\n");
	printf("Mode: %s Verbose: %s Tracing: %s\n", mode,
		verbose ? "on" : "off", trace ? "on" : "off");
}

intr()
{
	longjmp(toplevel, -1);
}

char *
tail(filename)
	char *filename;
{
	register char *s;
	
	while (*filename) {
		s = rindex(filename, '/');
		if (s == NULL)
			break;
		if (s[1])
			return (s + 1);
		*s = '\0';
	}
	return (filename);
}

/*
 * Command parser.
 */
command(top)
	int top;
{
	register struct cmd *c;

	if (!top)
		putchar('\n');
	else
		sigset(SIGINT, SIG_DFL);
	for (;;) {
		printf("%s> ", prompt);
		if (gets(line) == 0)
			break;
		if (line[0] == 0)
			break;
		makeargv();
		c = getcmd(margv[0]);
		if (c == (struct cmd *)-1) {
			printf("?Ambiguous command\n");
			continue;
		}
		if (c == 0) {
			printf("?Invalid command\n");
			continue;
		}
		(*c->handler)(margc, margv);
		if (c->handler != help)
			break;
	}
	longjmp(toplevel, 1);
}

struct cmd *
getcmd(name)
	register char *name;
{
	register char *p, *q;
	register struct cmd *c, *found;
	register int nmatches, longest;

	longest = 0;
	nmatches = 0;
	found = 0;
	for (c = cmdtab; p = c->name; c++) {
		for (q = name; *q == *p++; q++)
			if (*q == 0)		/* exact match? */
				return (c);
		if (!*q) {			/* the name was a prefix */
			if (q - name > longest) {
				longest = q - name;
				nmatches = 1;
				found = c;
			} else if (q - name == longest)
				nmatches++;
		}
	}
	if (nmatches > 1)
		return ((struct cmd *)-1);
	return (found);
}

/*
 * Slice a string up into argc/argv.
 */
makeargv()
{
	register char *cp;
	register char **argp = margv;

	margc = 0;
	for (cp = line; *cp;) {
		while (isspace(*cp))
			cp++;
		if (*cp == '\0')
			break;
		*argp++ = cp;
		margc += 1;
		while (*cp != '\0' && !isspace(*cp))
			cp++;
		if (*cp == '\0')
			break;
		*cp++ = '\0';
	}
	*argp++ = 0;
}

/*VARARGS*/
quit()
{
	exit(0);
}

/*
 * Help command.
 * Call each command handler with argc == 0 and argv[0] == name.
 */
help(argc, argv)
	int argc;
	char *argv[];
{
	register struct cmd *c;

	if (argc == 1) {
		printf("Commands may be abbreviated.  Commands are:\n\n");
		for (c = cmdtab; c->name; c++)
			printf("%-*s\t%s\n", HELPINDENT, c->name, c->help);
		return;
	}
	while (--argc > 0) {
		register char *arg;
		arg = *++argv;
		c = getcmd(arg);
		if (c == (struct cmd *)-1)
			printf("?Ambiguous help command %s\n", arg);
		else if (c == (struct cmd *)0)
			printf("?Invalid help command %s\n", arg);
		else
			printf("%s\n", c->help);
	}
}

/*
 * Call routine with argc, argv set from args (terminated by 0).
 */
/* VARARGS2 */
call(routine, args)
	int (*routine)();
	int args;
{
	register int *argp;
	register int argc;

	for (argc = 0, argp = &args; *argp++ != 0; argc++)
		;
	(*routine)(argc, &args);
}

/*VARARGS*/
settrace()
{
	trace = !trace;
	printf("Packet tracing %s.\n", trace ? "on" : "off");
}

/*VARARGS*/
setverbose()
{
	verbose = !verbose;
	printf("Verbose mode %s.\n", verbose ? "on" : "off");
}
Commit	Line	Data
4d5e33bd	1	/* main.c 4.2 82/10/08 */
c3353d83 SL	2
	3	/*
	4	* TFTP User Program -- Command Interface.
	5	*/
	6	#include <sys/types.h>
	7	#include <net/in.h>
	8	#include <sys/socket.h>
	9	#include <signal.h>
	10	#include <stdio.h>
	11	#include <errno.h>
	12	#include <setjmp.h>
	13	#include <ctype.h>
4d5e33bd	14	#include <netdb.h>
c3353d83	15
4d5e33bd	16	struct sockaddr_in sin = { AF_INET };
c3353d83 SL	17	int f;
	18	int options;
	19	int trace;
	20	int verbose;
	21	int connected;
	22	char mode[32];
	23	char line[200];
	24	int margc;
	25	char *margv[20];
	26	char *prompt = "tftp";
	27	jmp_buf toplevel;
	28	int intr();
4d5e33bd	29	struct servent *sp;
c3353d83 SL	30
	31	int quit(), help(), setverbose(), settrace(), status();
	32	int get(), put(), setpeer(), setmode();
	33
	34	#define HELPINDENT (sizeof("connect"))
	35
	36	struct cmd {
	37	char *name;
	38	char *help;
	39	int (*handler)();
	40	};
	41
	42	char vhelp[] = "toggle verbose mode";
	43	char thelp[] = "toggle packet tracing";
	44	char chelp[] = "connect to remote tftp";
	45	char qhelp[] = "exit tftp";
	46	char hhelp[] = "print help information";
	47	char shelp[] = "send file";
	48	char rhelp[] = "receive file";
	49	char mhelp[] = "set file transfer mode";
	50	char sthelp[] = "show current status";
	51
	52	struct cmd cmdtab[] = {
	53	{ "connect", chelp, setpeer },
	54	{ "mode", mhelp, setmode },
	55	{ "put", shelp, put },
	56	{ "get", rhelp, get },
	57	{ "quit", qhelp, quit },
	58	{ "verbose", vhelp, setverbose },
	59	{ "trace", thelp, settrace },
	60	{ "status", sthelp, status },
	61	{ "?", hhelp, help },
	62	0
	63	};
	64
	65	struct cmd *getcmd();
	66	char *tail();
	67	char *index();
	68	char *rindex();
	69
	70	main(argc, argv)
	71	char *argv[];
	72	{
4d5e33bd SL	73	sp = getservbyname("tftp", "udp");
	74	if (sp == 0) {
	75	fprintf(stderr, "tftp: udp/tftp: unknown service\n");
	76	exit(1);
	77	}
	78	sin.sin_port = htons(sp->s_port);
c3353d83 SL	79	if (argc > 1 && !strcmp(argv[1], "-d")) {
	80	options \|= SO_DEBUG;
	81	argc--, argv++;
	82	}
	83	f = socket(SOCK_DGRAM, 0, 0, options);
	84	if (f < 0) {
	85	perror("socket");
	86	exit(3);
	87	}
c3353d83 SL	88	strcpy(mode, "netascii");
	89	if (argc > 1) {
	90	if (setjmp(toplevel) != 0)
	91	exit(0);
	92	setpeer(argc, argv);
	93	}
	94	setjmp(toplevel);
	95	for (;;)
	96	command(1);
	97	}
	98
4d5e33bd SL	99	char *hostname;
4d5e33bd SL	100	char hnamebuf[32];
c3353d83 SL	101
	102	setpeer(argc, argv)
	103	int argc;
	104	char *argv[];
	105	{
	106	register int c;
4d5e33bd	107	struct hostent *host;
c3353d83 SL	108
	109	if (argc < 2) {
	110	strcpy(line, "Connect ");
	111	printf("(to) ");
	112	gets(&line[strlen(line)]);
	113	makeargv();
	114	argc = margc;
	115	argv = margv;
	116	}
	117	if (argc > 3) {
	118	printf("usage: %s host-name [port]\n", argv[0]);
	119	return;
	120	}
4d5e33bd SL	121	host = gethostbyname(argv[1]);
	122	if (host) {
	123	bcopy(host->h_addr, &sin.sin_addr, host->h_length);
	124	hostname = host->h_name;
	125	} else {
	126	sin.sin_addr.s_addr = inet_addr(argv[1]);
	127	if (sin.sin_addr.s_addr == -1) {
	128	connected = 0;
	129	printf("%s: unknown host\n", argv[1]);
	130	return;
	131	}
	132	strcpy(hnamebuf, argv[1]);
	133	hostname = hnamebuf;
c3353d83	134	}
4d5e33bd	135	sin.sin_port = sp->s_port;
c3353d83 SL	136	if (argc == 3) {
	137	sin.sin_port = atoi(argv[2]);
	138	if (sin.sin_port < 0) {
	139	printf("%s: bad port number\n", argv[2]);
	140	connected = 0;
	141	return;
	142	}
4d5e33bd	143	}
c3353d83	144	#if vax \|\| pdp11
4d5e33bd	145	sin.sin_port = htons(sin.sin_port);
c3353d83	146	#endif
c3353d83 SL	147	connected = 1;
	148	}
	149
	150	struct modes {
	151	char *m_name;
	152	char *m_mode;
	153	} modes[] = {
	154	{ "ascii", "netascii" },
	155	{ "binary", "octect" },
	156	{ "mail", "mail" },
	157	{ 0, 0 }
	158	};
	159
	160	setmode(argc, argv)
	161	char *argv[];
	162	{
	163	register struct modes *p;
	164
	165	if (argc > 2) {
	166	char *sep;
	167
	168	printf("usage: %s [", argv[0]);
	169	sep = " ";
	170	for (p = modes; p->m_name; p++) {
	171	printf("%s%s", sep, p->m_name);
	172	if (*sep == ' ')
	173	sep = " \| ";
	174	}
	175	printf(" ]\n");
	176	return;
	177	}
	178	if (argc < 2) {
	179	printf("Using %s mode to transfer files.\n", mode);
	180	return;
	181	}
	182	for (p = modes; p->m_name; p++)
	183	if (strcmp(argv[1], p->m_name) == 0)
	184	break;
	185	if (p->m_name)
	186	strcpy(mode, p->m_mode);
	187	else
	188	printf("%s: unknown mode\n", argv[1]);
	189	}
	190
	191	/*
	192	* Send file(s).
	193	*/
	194	put(argc, argv)
	195	char *argv[];
	196	{
	197	int fd;
	198	register int n, addr;
	199	register char cp, targ;
	200
	201	if (argc < 2) {
	202	strcpy(line, "send ");
	203	printf("(file) ");
	204	gets(&line[strlen(line)]);
	205	makeargv();
	206	argc = margc;
	207	argv = margv;
	208	}
	209	if (argc < 2) {
	210	putusage(argv[0]);
211	return;
212	}
213	targ = argv[argc - 1];
214	if (index(argv[argc - 1], ':')) {
4d5e33bd SL	215	char *cp;
4d5e33bd SL	216	struct hostent *hp;
c3353d83 SL	217
	218	for (n = 1; n < argc - 1; n++)
	219	if (index(argv[n], ':')) {
	220	putusage(argv[0]);
	221	return;
	222	}
4d5e33bd SL	223	cp = argv[argc - 1];
4d5e33bd SL	224	targ = index(cp, ':');
c3353d83	225	*targ++ = 0;
4d5e33bd SL	226	hp = gethostbyname(cp);
	227	if (hp == 0) {
	228	printf("%s: Unknown host.\n", cp);
c3353d83 SL	229	return;
c3353d83 SL	230	}
4d5e33bd SL	231	bcopy(hp->h_addr, &sin.sin_addr, hp->h_length);
4d5e33bd SL	232	sin.sin_family = hp->h_addrtype;
c3353d83	233	connected = 1;
4d5e33bd	234	hostname = hp->h_name;
c3353d83 SL	235	}
	236	if (!connected) {
	237	printf("No target machine specified.\n");
	238	return;
	239	}
	240	sigset(SIGINT, intr);
	241	if (argc < 4) {
	242	cp = argc == 2 ? tail(targ) : argv[1];
	243	fd = open(cp);
	244	if (fd < 0) {
	245	perror(cp);
	246	return;
	247	}
	248	sendfile(fd, targ);
	249	return;
	250	}
	251	cp = index(targ, '\0');
	252	*cp++ = '/';
	253	for (n = 1; n < argc - 1; n++) {
	254	strcpy(cp, tail(argv[n]));
	255	fd = open(argv[n], 0);
	256	if (fd < 0) {
	257	perror(argv[n]);
	258	continue;
	259	}
	260	sendfile(fd, targ);
	261	}
	262	}
	263
	264	putusage(s)
	265	char *s;
	266	{
	267	printf("usage: %s file ... host:target, or\n", s);
	268	printf(" %s file ... target (when already connected)\n", s);
	269	}
	270
	271	/*
	272	* Receive file(s).
	273	*/
	274	get(argc, argv)
	275	char *argv[];
	276	{
	277	int fd;
	278	register int n, addr;
	279	register char *cp;
	280	char *src;
	281
	282	if (argc < 2) {
	283	strcpy(line, "get ");
	284	printf("(files) ");
	285	gets(&line[strlen(line)]);
	286	makeargv();
	287	argc = margc;
	288	argv = margv;
	289	}
	290	if (argc < 2) {
	291	getusage(argv[0]);
	292	return;
	293	}
	294	if (!connected)
	295	for (n = 1; n < argc - 1; n++)
	296	if (index(argv[n], ':') == 0) {
	297	getusage(argv[0]);
	298	return;
299	}
300	sigset(SIGINT, intr);
301	for (n = 1; argc == 2 \|\| n < argc - 1; n++) {
302	src = index(argv[n], ':');
303	if (src == NULL)
304	src = argv[n];
305	else {
4d5e33bd SL	306	struct hostent *hp;
4d5e33bd SL	307
c3353d83	308	*src++ = 0;
4d5e33bd SL	309	hp = gethostbyname(argv[n]);
4d5e33bd SL	310	if (hp == 0) {
c3353d83 SL	311	printf("%s: Unknown host.\n", argv[n]);
	312	continue;
	313	}
4d5e33bd SL	314	bcopy(hp->h_addr, &sin.sin_addr, hp->h_length);
4d5e33bd SL	315	sin.sin_family = hp->h_addrtype;
c3353d83	316	connected = 1;
4d5e33bd	317	hostname = hp->h_name;
c3353d83 SL	318	}
	319	if (argc < 4) {
	320	cp = argc == 3 ? argv[2] : tail(src);
	321	fd = creat(cp, 0644);
	322	if (fd < 0) {
	323	perror(cp);
	324	return;
	325	}
	326	recvfile(fd, src);
	327	break;
	328	}
	329	cp = index(argv[argc - 1], '\0');
	330	*cp++ = '/';
	331	strcpy(cp, tail(src));
	332	fd = creat(src, 0644);
	333	if (fd < 0) {
	334	perror(src);
	335	continue;
	336	}
	337	recvfile(fd, src);
	338	}
	339	}
	340
	341	getusage(s)
	342	{
	343	printf("usage: %s host:file host:file ... file, or\n", s);
	344	printf(" %s file file ... file if connected\n", s);
	345	}
	346
	347	status(argc, argv)
	348	char *argv[];
	349	{
	350	if (connected)
4d5e33bd	351	printf("Connected to %s.\n", hostname);
c3353d83 SL	352	else
	353	printf("Not connected.\n");
	354	printf("Mode: %s Verbose: %s Tracing: %s\n", mode,
	355	verbose ? "on" : "off", trace ? "on" : "off");
	356	}
	357
	358	intr()
	359	{
	360	longjmp(toplevel, -1);
	361	}
	362
	363	char *
	364	tail(filename)
	365	char *filename;
	366	{
	367	register char *s;
	368
	369	while (*filename) {
	370	s = rindex(filename, '/');
	371	if (s == NULL)
	372	break;
	373	if (s[1])
	374	return (s + 1);
	375	*s = '\0';
	376	}
	377	return (filename);
	378	}
	379
	380	/*
	381	* Command parser.
	382	*/
	383	command(top)
	384	int top;
	385	{
	386	register struct cmd *c;
	387
	388	if (!top)
	389	putchar('\n');
	390	else
	391	sigset(SIGINT, SIG_DFL);
	392	for (;;) {
	393	printf("%s> ", prompt);
	394	if (gets(line) == 0)
	395	break;
	396	if (line[0] == 0)
	397	break;
	398	makeargv();
	399	c = getcmd(margv[0]);
	400	if (c == (struct cmd *)-1) {
	401	printf("?Ambiguous command\n");
	402	continue;
	403	}
	404	if (c == 0) {
	405	printf("?Invalid command\n");
	406	continue;
	407	}
	408	(*c->handler)(margc, margv);
	409	if (c->handler != help)
	410	break;
	411	}
	412	longjmp(toplevel, 1);
	413	}
	414
	415	struct cmd *
416	getcmd(name)
417	register char *name;
418	{
419	register char p, q;
420	register struct cmd c, found;
421	register int nmatches, longest;
422
423	longest = 0;
424	nmatches = 0;
425	found = 0;
426	for (c = cmdtab; p = c->name; c++) {
427	for (q = name; q == p++; q++)
428	if (q == 0) / exact match? */
429	return (c);
430	if (!q) { / the name was a prefix */
431	if (q - name > longest) {
432	longest = q - name;
433	nmatches = 1;
434	found = c;
435	} else if (q - name == longest)
436	nmatches++;
437	}
438	}
439	if (nmatches > 1)
440	return ((struct cmd *)-1);
441	return (found);
442	}
443
444	/*
445	* Slice a string up into argc/argv.
446	*/
447	makeargv()
448	{
449	register char *cp;
450	register char **argp = margv;
451
452	margc = 0;
453	for (cp = line; *cp;) {
454	while (isspace(*cp))
455	cp++;
456	if (*cp == '\0')
457	break;
458	*argp++ = cp;
459	margc += 1;
460	while (cp != '\0' && !isspace(cp))
461	cp++;
462	if (*cp == '\0')
463	break;
464	*cp++ = '\0';
465	}
466	*argp++ = 0;
467	}
468
469	/VARARGS/
470	quit()
471	{
472	exit(0);
473	}
474
475	/*
476	* Help command.
477	* Call each command handler with argc == 0 and argv[0] == name.
478	*/
479	help(argc, argv)
480	int argc;
481	char *argv[];
482	{
483	register struct cmd *c;
484
485	if (argc == 1) {
486	printf("Commands may be abbreviated. Commands are:\n\n");
487	for (c = cmdtab; c->name; c++)
488	printf("%-*s\t%s\n", HELPINDENT, c->name, c->help);
489	return;
490	}
491	while (--argc > 0) {
492	register char *arg;
493	arg = *++argv;
494	c = getcmd(arg);
495	if (c == (struct cmd *)-1)
496	printf("?Ambiguous help command %s\n", arg);
497	else if (c == (struct cmd *)0)
498	printf("?Invalid help command %s\n", arg);
499	else
500	printf("%s\n", c->help);
501	}
502	}
503
504	/*
505	* Call routine with argc, argv set from args (terminated by 0).
506	*/
507	/* VARARGS2 */
508	call(routine, args)
509	int (*routine)();
510	int args;
511	{
512	register int *argp;
513	register int argc;
514
515	for (argc = 0, argp = &args; *argp++ != 0; argc++)
516	;
517	(*routine)(argc, &args);
518	}
519
520	/VARARGS/
521	settrace()
522	{
523	trace = !trace;
524	printf("Packet tracing %s.\n", trace ? "on" : "off");
525	}
526
527	/VARARGS/
528	setverbose()
529	{
530	verbose = !verbose;
531	printf("Verbose mode %s.\n", verbose ? "on" : "off");
532	}