[unix-history] / .ref-fdb8e4aac282b72d4670aa3a26d9bba07afc7e6f / usr / src / lib / libterm / termcap.c

/*
 * Copyright (c) 1980 The Regents of the University of California.
 * All rights reserved.
 *
 * %sccs.include.redist.c%
 */

#ifndef lint
static char sccsid[] = "@(#)termcap.c	5.5 (Berkeley) %G%";
#endif /* not lint */

#define	BUFSIZ		1024
#define MAXHOP		32	/* max number of tc= indirections */
#define	PBUFSIZ		512	/* max length of filename path */
#define	PVECSIZ		32	/* max number of names in path */

#include <ctype.h>
#include "pathnames.h"

/*
 * termcap - routines for dealing with the terminal capability data base
 *
 * BUG:		Should use a "last" pointer in tbuf, so that searching
 *		for capabilities alphabetically would not be a n**2/2
 *		process when large numbers of capabilities are given.
 * Note:	If we add a last pointer now we will screw up the
 *		tc capability. We really should compile termcap.
 *
 * Essentially all the work here is scanning and decoding escapes
 * in string capabilities.  We don't use stdio because the editor
 * doesn't, and because living w/o it is not hard.
 */

static	char *tbuf;
static	int hopcount;	/* detect infinite loops in termcap, init 0 */
static	char pathbuf[PBUFSIZ];		/* holds raw path of filenames */
static	char *pathvec[PVECSIZ];		/* to point to names in pathbuf */
static	char **pvec;			/* holds usable tail of path vector */
char	*tskip();
char	*tgetstr();
char	*tdecode();
char	*getenv();

/*
 * Get an entry for terminal name in buffer bp from the termcap file.
 */
tgetent(bp, name)
	char *bp, *name;
{
	register char *p;
	register char *cp;
	register int c;
	char *term, *home, *termpath;
	char **fname = pathvec;

	pvec = pathvec;
	tbuf = bp;
	p = pathbuf;
	cp = getenv("TERMCAP");
	/*
	 * TERMCAP can have one of two things in it. It can be the
	 * name of a file to use instead of /etc/termcap. In this
	 * case it better start with a "/". Or it can be an entry to
	 * use so we don't have to read the file. In this case it
	 * has to already have the newlines crunched out.  If TERMCAP
	 * does not hold a file name then a path of names is searched
	 * instead.  The path is found in the TERMPATH variable, or
	 * becomes "$HOME/.termcap /etc/termcap" if no TERMPATH exists.
	 */
	if (!cp || *cp != '/') {	/* no TERMCAP or it holds an entry */
		if (termpath = getenv("TERMPATH"))
			strncpy(pathbuf, termpath, PBUFSIZ);
		else {
			if (home = getenv("HOME")) {	/* set up default */
				p += strlen(home);	/* path, looking in */
				strcpy(pathbuf, home);	/* $HOME first */
				*p++ = '/';
			}	/* if no $HOME look in current directory */
			strncpy(p, _PATH_DEF, PBUFSIZ - (p - pathbuf));
		}
	}
	else				/* user-defined name in TERMCAP */
		strncpy(pathbuf, cp, PBUFSIZ);	/* still can be tokenized */

	*fname++ = pathbuf;	/* tokenize path into vector of names */
	while (*++p)
		if (*p == ' ' || *p == ':') {
			*p = '\0';
			while (*++p)
				if (*p != ' ' && *p != ':')
					break;
			if (*p == '\0')
				break;
			*fname++ = p;
			if (fname >= pathvec + PVECSIZ) {
				fname--;
				break;
			}
		}
	*fname = (char *) 0;			/* mark end of vector */
	if (cp && *cp && *cp != '/') {
		tbuf = cp;
		c = tnamatch(name);
		tbuf = bp;
		if (c) {
			strcpy(bp,cp);
			return (tnchktc());
		}
	}
	return (tfindent(bp, name));	/* find terminal entry in path */
}

/*
 * tfindent - reads through the list of files in pathvec as if they were one
 * continuous file searching for terminal entries along the way.  It will
 * participate in indirect recursion if the call to tnchktc() finds a tc=
 * field, which is only searched for in the current file and files ocurring
 * after it in pathvec.  The usable part of this vector is kept in the global
 * variable pvec.  Terminal entries may not be broken across files.  Parse is
 * very rudimentary; we just notice escaped newlines.
 */
tfindent(bp, name)
	char *bp, *name;
{
	register char *cp;
	register int c;
	register int i, cnt;
	char ibuf[BUFSIZ];
	int opencnt = 0;
	int tf;

	tbuf = bp;
nextfile:
	i = cnt = 0;
	while (*pvec && (tf = open(*pvec, 0)) < 0)
		pvec++;
	if (!*pvec)
		return (opencnt ? 0 : -1);
	opencnt++;
	for (;;) {
		cp = bp;
		for (;;) {
			if (i == cnt) {
				cnt = read(tf, ibuf, BUFSIZ);
				if (cnt <= 0) {
					close(tf);
					pvec++;
					goto nextfile;
				}
				i = 0;
			}
			c = ibuf[i++];
			if (c == '\n') {
				if (cp > bp && cp[-1] == '\\'){
					cp--;
					continue;
				}
				break;
			}
			if (cp >= bp+BUFSIZ) {
				write(2,"Termcap entry too long\n", 23);
				break;
			} else
				*cp++ = c;
		}
		*cp = 0;

		/*
		 * The real work for the match.
		 */
		if (tnamatch(name)) {
			close(tf);
			return(tnchktc());
		}
	}
}

/*
 * tnchktc: check the last entry, see if it's tc=xxx. If so,
 * recursively find xxx and append that entry (minus the names)
 * to take the place of the tc=xxx entry. This allows termcap
 * entries to say "like an HP2621 but doesn't turn on the labels".
 * Note that this works because of the left to right scan.
 */
tnchktc()
{
	register char *p, *q;
	char tcname[16];	/* name of similar terminal */
	char tcbuf[BUFSIZ];
	char *holdtbuf = tbuf;
	int l;

	p = tbuf + strlen(tbuf) - 2;	/* before the last colon */
	while (*--p != ':')
		if (p<tbuf) {
			write(2, "Bad termcap entry\n", 18);
			return (0);
		}
	p++;
	/* p now points to beginning of last field */
	if (p[0] != 't' || p[1] != 'c')
		return(1);
	strcpy(tcname,p+3);
	q = tcname;
	while (*q && *q != ':')
		q++;
	*q = 0;
	if (++hopcount > MAXHOP) {
		write(2, "Infinite tc= loop\n", 18);
		return (0);
	}
	if (tfindent(tcbuf, tcname) != 1) {
		hopcount = 0;		/* unwind recursion */
		return(0);
	}
	for (q=tcbuf; *q != ':'; q++)
		;
	l = p - holdtbuf + strlen(q);
	if (l > BUFSIZ) {
		write(2, "Termcap entry too long\n", 23);
		q[BUFSIZ - (p-tbuf)] = 0;
	}
	strcpy(p, q+1);
	tbuf = holdtbuf;
	hopcount = 0;			/* unwind recursion */
	return(1);
}

/*
 * Tnamatch deals with name matching.  The first field of the termcap
 * entry is a sequence of names separated by |'s, so we compare
 * against each such name.  The normal : terminator after the last
 * name (before the first field) stops us.
 */
tnamatch(np)
	char *np;
{
	register char *Np, *Bp;

	Bp = tbuf;
	if (*Bp == '#')
		return(0);
	for (;;) {
		for (Np = np; *Np && *Bp == *Np; Bp++, Np++)
			continue;
		if (*Np == 0 && (*Bp == '|' || *Bp == ':' || *Bp == 0))
			return (1);
		while (*Bp && *Bp != ':' && *Bp != '|')
			Bp++;
		if (*Bp == 0 || *Bp == ':')
			return (0);
		Bp++;
	}
}

/*
 * Skip to the next field.  Notice that this is very dumb, not
 * knowing about \: escapes or any such.  If necessary, :'s can be put
 * into the termcap file in octal.
 */
static char *
tskip(bp)
	register char *bp;
{

	while (*bp && *bp != ':')
		bp++;
	if (*bp == ':')
		bp++;
	return (bp);
}

/*
 * Return the (numeric) option id.
 * Numeric options look like
 *	li#80
 * i.e. the option string is separated from the numeric value by
 * a # character.  If the option is not found we return -1.
 * Note that we handle octal numbers beginning with 0.
 */
tgetnum(id)
	char *id;
{
	register int i, base;
	register char *bp = tbuf;

	for (;;) {
		bp = tskip(bp);
		if (*bp == 0)
			return (-1);
		if (*bp++ != id[0] || *bp == 0 || *bp++ != id[1])
			continue;
		if (*bp == '@')
			return(-1);
		if (*bp != '#')
			continue;
		bp++;
		base = 10;
		if (*bp == '0')
			base = 8;
		i = 0;
		while (isdigit(*bp))
			i *= base, i += *bp++ - '0';
		return (i);
	}
}

/*
 * Handle a flag option.
 * Flag options are given "naked", i.e. followed by a : or the end
 * of the buffer.  Return 1 if we find the option, or 0 if it is
 * not given.
 */
tgetflag(id)
	char *id;
{
	register char *bp = tbuf;

	for (;;) {
		bp = tskip(bp);
		if (!*bp)
			return (0);
		if (*bp++ == id[0] && *bp != 0 && *bp++ == id[1]) {
			if (!*bp || *bp == ':')
				return (1);
			else if (*bp == '@')
				return(0);
		}
	}
}

/*
 * Get a string valued option.
 * These are given as
 *	cl=^Z
 * Much decoding is done on the strings, and the strings are
 * placed in area, which is a ref parameter which is updated.
 * No checking on area overflow.
 */
char *
tgetstr(id, area)
	char *id, **area;
{
	register char *bp = tbuf;

	for (;;) {
		bp = tskip(bp);
		if (!*bp)
			return (0);
		if (*bp++ != id[0] || *bp == 0 || *bp++ != id[1])
			continue;
		if (*bp == '@')
			return(0);
		if (*bp != '=')
			continue;
		bp++;
		return (tdecode(bp, area));
	}
}

/*
 * Tdecode does the grung work to decode the
 * string capability escapes.
 */
static char *
tdecode(str, area)
	register char *str;
	char **area;
{
	register char *cp;
	register int c;
	register char *dp;
	int i;

	cp = *area;
	while ((c = *str++) && c != ':') {
		switch (c) {

		case '^':
			c = *str++ & 037;
			break;

		case '\\':
			dp = "E\033^^\\\\::n\nr\rt\tb\bf\f";
			c = *str++;
nextc:
			if (*dp++ == c) {
				c = *dp++;
				break;
			}
			dp++;
			if (*dp)
				goto nextc;
			if (isdigit(c)) {
				c -= '0', i = 2;
				do
					c <<= 3, c |= *str++ - '0';
				while (--i && isdigit(*str));
			}
			break;
		}
		*cp++ = c;
	}
	*cp++ = 0;
	str = *area;
	*area = cp;
	return (str);
}
Commit	Line	Data
6468808a	1	/*
31a14b65 KB	2	* Copyright (c) 1980 The Regents of the University of California.
	3	* All rights reserved.
	4	*
9c1340a5	5	* %sccs.include.redist.c%
6468808a DF	6	*/
6468808a DF	7
7bc051a7	8	#ifndef lint
9c1340a5	9	static char sccsid[] = "@(#)termcap.c 5.5 (Berkeley) %G%";
31a14b65	10	#endif /* not lint */
7bc051a7 SL	11
	12	#define BUFSIZ 1024
	13	#define MAXHOP 32 /* max number of tc= indirections */
d89a08fa JK	14	#define PBUFSIZ 512 /* max length of filename path */
d89a08fa JK	15	#define PVECSIZ 32 /* max number of names in path */
7bc051a7 SL	16
7bc051a7 SL	17	#include <ctype.h>
e5f47b7a KB	18	#include "pathnames.h"
e5f47b7a KB	19
7bc051a7 SL	20	/*
	21	* termcap - routines for dealing with the terminal capability data base
	22	*
	23	* BUG: Should use a "last" pointer in tbuf, so that searching
	24	* for capabilities alphabetically would not be a n**2/2
	25	* process when large numbers of capabilities are given.
	26	* Note: If we add a last pointer now we will screw up the
	27	* tc capability. We really should compile termcap.
	28	*
	29	* Essentially all the work here is scanning and decoding escapes
	30	* in string capabilities. We don't use stdio because the editor
	31	* doesn't, and because living w/o it is not hard.
	32	*/
	33
	34	static char *tbuf;
	35	static int hopcount; /* detect infinite loops in termcap, init 0 */
d89a08fa JK	36	static char pathbuf[PBUFSIZ]; /* holds raw path of filenames */
	37	static char pathvec[PVECSIZ]; / to point to names in pathbuf */
	38	static char *pvec; / holds usable tail of path vector */
7bc051a7 SL	39	char *tskip();
	40	char *tgetstr();
	41	char *tdecode();
	42	char *getenv();
	43
	44	/*
d89a08fa	45	* Get an entry for terminal name in buffer bp from the termcap file.
7bc051a7 SL	46	*/
	47	tgetent(bp, name)
	48	char bp, name;
	49	{
d89a08fa	50	register char *p;
7bc051a7 SL	51	register char *cp;
7bc051a7 SL	52	register int c;
d89a08fa JK	53	char term, home, *termpath;
d89a08fa JK	54	char **fname = pathvec;
7bc051a7	55
d89a08fa	56	pvec = pathvec;
7bc051a7	57	tbuf = bp;
d89a08fa	58	p = pathbuf;
7bc051a7 SL	59	cp = getenv("TERMCAP");
	60	/*
	61	* TERMCAP can have one of two things in it. It can be the
	62	* name of a file to use instead of /etc/termcap. In this
	63	* case it better start with a "/". Or it can be an entry to
	64	* use so we don't have to read the file. In this case it
d89a08fa JK	65	* has to already have the newlines crunched out. If TERMCAP
	66	* does not hold a file name then a path of names is searched
	67	* instead. The path is found in the TERMPATH variable, or
	68	* becomes "$HOME/.termcap /etc/termcap" if no TERMPATH exists.
7bc051a7	69	*/
d89a08fa JK	70	if (!cp \|\| cp != '/') { / no TERMCAP or it holds an entry */
	71	if (termpath = getenv("TERMPATH"))
	72	strncpy(pathbuf, termpath, PBUFSIZ);
	73	else {
	74	if (home = getenv("HOME")) { /* set up default */
	75	p += strlen(home); /* path, looking in */
	76	strcpy(pathbuf, home); /* $HOME first */
	77	*p++ = '/';
	78	} /* if no $HOME look in current directory */
e5f47b7a	79	strncpy(p, _PATH_DEF, PBUFSIZ - (p - pathbuf));
e42cb6f9	80	}
7bc051a7	81	}
d89a08fa JK	82	else /* user-defined name in TERMCAP */
d89a08fa JK	83	strncpy(pathbuf, cp, PBUFSIZ); /* still can be tokenized */
e5f47b7a	84
d89a08fa JK	85	fname++ = pathbuf; / tokenize path into vector of names */
	86	while (*++p)
	87	if (p == ' ' \|\| p == ':') {
	88	*p = '\0';
	89	while (*++p)
	90	if (p != ' ' && p != ':')
	91	break;
	92	if (*p == '\0')
	93	break;
	94	*fname++ = p;
	95	if (fname >= pathvec + PVECSIZ) {
	96	fname--;
	97	break;
	98	}
	99	}
	100	fname = (char ) 0; /* mark end of vector */
	101	if (cp && cp && cp != '/') {
	102	tbuf = cp;
	103	c = tnamatch(name);
	104	tbuf = bp;
	105	if (c) {
	106	strcpy(bp,cp);
	107	return (tnchktc());
	108	}
	109	}
	110	return (tfindent(bp, name)); /* find terminal entry in path */
	111	}
	112
	113	/*
	114	* tfindent - reads through the list of files in pathvec as if they were one
	115	* continuous file searching for terminal entries along the way. It will
	116	* participate in indirect recursion if the call to tnchktc() finds a tc=
	117	* field, which is only searched for in the current file and files ocurring
	118	* after it in pathvec. The usable part of this vector is kept in the global
	119	* variable pvec. Terminal entries may not be broken across files. Parse is
	120	* very rudimentary; we just notice escaped newlines.
	121	*/
	122	tfindent(bp, name)
	123	char bp, name;
	124	{
	125	register char *cp;
	126	register int c;
	127	register int i, cnt;
	128	char ibuf[BUFSIZ];
	129	int opencnt = 0;
	130	int tf;
	131
	132	tbuf = bp;
	133	nextfile:
	134	i = cnt = 0;
	135	while (pvec && (tf = open(pvec, 0)) < 0)
	136	pvec++;
	137	if (!*pvec)
	138	return (opencnt ? 0 : -1);
	139	opencnt++;
7bc051a7 SL	140	for (;;) {
	141	cp = bp;
	142	for (;;) {
	143	if (i == cnt) {
	144	cnt = read(tf, ibuf, BUFSIZ);
	145	if (cnt <= 0) {
	146	close(tf);
d89a08fa JK	147	pvec++;
d89a08fa JK	148	goto nextfile;
7bc051a7 SL	149	}
	150	i = 0;
	151	}
	152	c = ibuf[i++];
	153	if (c == '\n') {
	154	if (cp > bp && cp[-1] == '\\'){
	155	cp--;
	156	continue;
	157	}
	158	break;
	159	}
	160	if (cp >= bp+BUFSIZ) {
	161	write(2,"Termcap entry too long\n", 23);
	162	break;
	163	} else
	164	*cp++ = c;
	165	}
	166	*cp = 0;
	167
	168	/*
	169	* The real work for the match.
	170	*/
	171	if (tnamatch(name)) {
	172	close(tf);
	173	return(tnchktc());
	174	}
	175	}
	176	}
	177
	178	/*
	179	* tnchktc: check the last entry, see if it's tc=xxx. If so,
	180	* recursively find xxx and append that entry (minus the names)
	181	* to take the place of the tc=xxx entry. This allows termcap
	182	* entries to say "like an HP2621 but doesn't turn on the labels".
	183	* Note that this works because of the left to right scan.
	184	*/
	185	tnchktc()
	186	{
	187	register char p, q;
	188	char tcname[16]; /* name of similar terminal */
	189	char tcbuf[BUFSIZ];
	190	char *holdtbuf = tbuf;
	191	int l;
	192
	193	p = tbuf + strlen(tbuf) - 2; /* before the last colon */
	194	while (*--p != ':')
	195	if (p<tbuf) {
	196	write(2, "Bad termcap entry\n", 18);
	197	return (0);
	198	}
	199	p++;
	200	/* p now points to beginning of last field */
	201	if (p[0] != 't' \|\| p[1] != 'c')
	202	return(1);
	203	strcpy(tcname,p+3);
	204	q = tcname;
4a8ecd7e	205	while (q && q != ':')
7bc051a7 SL	206	q++;
	207	*q = 0;
	208	if (++hopcount > MAXHOP) {
	209	write(2, "Infinite tc= loop\n", 18);
	210	return (0);
	211	}
d89a08fa	212	if (tfindent(tcbuf, tcname) != 1) {
e97efd50	213	hopcount = 0; /* unwind recursion */
7bc051a7	214	return(0);
e97efd50	215	}
7bc051a7 SL	216	for (q=tcbuf; *q != ':'; q++)
	217	;
	218	l = p - holdtbuf + strlen(q);
	219	if (l > BUFSIZ) {
	220	write(2, "Termcap entry too long\n", 23);
	221	q[BUFSIZ - (p-tbuf)] = 0;
	222	}
	223	strcpy(p, q+1);
	224	tbuf = holdtbuf;
e97efd50	225	hopcount = 0; /* unwind recursion */
7bc051a7 SL	226	return(1);
	227	}
	228
	229	/*
	230	* Tnamatch deals with name matching. The first field of the termcap
	231	* entry is a sequence of names separated by \|'s, so we compare
	232	* against each such name. The normal : terminator after the last
	233	* name (before the first field) stops us.
	234	*/
	235	tnamatch(np)
	236	char *np;
	237	{
	238	register char Np, Bp;
	239
	240	Bp = tbuf;
	241	if (*Bp == '#')
	242	return(0);
	243	for (;;) {
	244	for (Np = np; Np && Bp == *Np; Bp++, Np++)
	245	continue;
	246	if (Np == 0 && (Bp == '\|' \|\| Bp == ':' \|\| Bp == 0))
	247	return (1);
	248	while (Bp && Bp != ':' && *Bp != '\|')
	249	Bp++;
	250	if (Bp == 0 \|\| Bp == ':')
	251	return (0);
	252	Bp++;
	253	}
	254	}
	255
	256	/*
	257	* Skip to the next field. Notice that this is very dumb, not
	258	* knowing about \: escapes or any such. If necessary, :'s can be put
	259	* into the termcap file in octal.
	260	*/
	261	static char *
	262	tskip(bp)
	263	register char *bp;
	264	{
	265
	266	while (bp && bp != ':')
	267	bp++;
	268	if (*bp == ':')
	269	bp++;
	270	return (bp);
	271	}
	272
	273	/*
	274	* Return the (numeric) option id.
	275	* Numeric options look like
	276	* li#80
	277	* i.e. the option string is separated from the numeric value by
	278	* a # character. If the option is not found we return -1.
	279	* Note that we handle octal numbers beginning with 0.
	280	*/
	281	tgetnum(id)
	282	char *id;
	283	{
	284	register int i, base;
	285	register char *bp = tbuf;
	286
	287	for (;;) {
	288	bp = tskip(bp);
	289	if (*bp == 0)
290	return (-1);
291	if (bp++ != id[0] \|\| bp == 0 \|\| *bp++ != id[1])
292	continue;
293	if (*bp == '@')
294	return(-1);
295	if (*bp != '#')
296	continue;
297	bp++;
298	base = 10;
299	if (*bp == '0')
300	base = 8;
301	i = 0;
302	while (isdigit(*bp))
303	i = base, i += bp++ - '0';
304	return (i);
305	}
306	}
307
308	/*
309	* Handle a flag option.
310	* Flag options are given "naked", i.e. followed by a : or the end
311	* of the buffer. Return 1 if we find the option, or 0 if it is
312	* not given.
313	*/
314	tgetflag(id)
315	char *id;
316	{
317	register char *bp = tbuf;
318
319	for (;;) {
320	bp = tskip(bp);
321	if (!*bp)
322	return (0);
323	if (bp++ == id[0] && bp != 0 && *bp++ == id[1]) {
324	if (!bp \|\| bp == ':')
325	return (1);
326	else if (*bp == '@')
327	return(0);
328	}
329	}
330	}
331
332	/*
333	* Get a string valued option.
334	* These are given as
335	* cl=^Z
336	* Much decoding is done on the strings, and the strings are
337	* placed in area, which is a ref parameter which is updated.
338	* No checking on area overflow.
339	*/
340	char *
341	tgetstr(id, area)
342	char id, *area;
343	{
344	register char *bp = tbuf;
345
346	for (;;) {
347	bp = tskip(bp);
348	if (!*bp)
349	return (0);
350	if (bp++ != id[0] \|\| bp == 0 \|\| *bp++ != id[1])
351	continue;
352	if (*bp == '@')
353	return(0);
354	if (*bp != '=')
355	continue;
356	bp++;
357	return (tdecode(bp, area));
358	}
359	}
360
361	/*
362	* Tdecode does the grung work to decode the
363	* string capability escapes.
364	*/
365	static char *
366	tdecode(str, area)
367	register char *str;
368	char **area;
369	{
370	register char *cp;
371	register int c;
372	register char *dp;
373	int i;
374
375	cp = *area;
376	while ((c = *str++) && c != ':') {
377	switch (c) {
378
379	case '^':
380	c = *str++ & 037;
381	break;
382
383	case '\\':
384	dp = "E\033^^\\\\::n\nr\rt\tb\bf\f";
385	c = *str++;
386	nextc:
387	if (*dp++ == c) {
388	c = *dp++;
389	break;
390	}
391	dp++;
392	if (*dp)
393	goto nextc;
394	if (isdigit(c)) {
395	c -= '0', i = 2;
396	do
397	c <<= 3, c \|= *str++ - '0';
398	while (--i && isdigit(*str));
399	}
400	break;
401	}
402	*cp++ = c;
403	}
404	*cp++ = 0;
405	str = *area;
406	*area = cp;
407	return (str);
408	}