termcap.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
* Copyright 1997 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
/* Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */
/* All Rights Reserved */
/*
* Copyright (c) 1980 Regents of the University of California.
* All rights reserved. The Berkeley software License Agreement
* specifies the terms and conditions for redistribution.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
/*LINTLIBRARY*/
#if 0
static char
sccsid[] = "@(#)termcap.c 1.11 88/02/08 SMI"; /* from UCB 5.1 6/5/85 */
#endif
#define BUFSIZ 1024
#define MAXHOP 32 /* max number of tc= indirections */
#define E_TERMCAP "/etc/termcap"
#include <sys/types.h>
#include <unistd.h>
#include <stdlib.h>
#include <stddef.h>
#include <string.h>
#include <strings.h>
#include <ctype.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 */
/* forward declarations */
static char *tdecode(char *, char **);
static void tngetsize(char *);
static char *tskip(char *bp);
static char *appendsmalldec(char *, int);
int tnamatch(char *);
int tnchktc(void);
/*
* Get an entry for terminal name in buffer bp,
* from the termcap file. Parse is very rudimentary;
* we just notice escaped newlines.
*/
int
tgetent(char *bp, char *name)
{
char *cp;
int c;
int i = 0;
ssize_t cnt = 0;
char ibuf[BUFSIZ];
int tf;
tbuf = bp;
tf = -1;
#ifndef V6
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 (cp && *cp) {
if (*cp == '/') {
tf = open(cp, 0);
} else {
tbuf = cp;
c = tnamatch(name);
tbuf = bp;
if (c) {
(void) strcpy(bp, cp);
return (tnchktc());
}
}
}
if (tf < 0)
tf = open(E_TERMCAP, 0);
#else
tf = open(E_TERMCAP, 0);
#endif
if (tf < 0)
return (-1);
for (;;) {
cp = bp;
for (;;) {
if (i == cnt) {
cnt = read(tf, ibuf, BUFSIZ);
if (cnt <= 0) {
(void) close(tf);
return (0);
}
i = 0;
}
c = ibuf[i++];
if (c == '\n') {
if (cp > bp && cp[-1] == '\\') {
cp--;
continue;
}
break;
}
if (cp >= bp+BUFSIZ) {
(void) write(2, "Termcap entry too long\n", 23);
break;
} else
*cp++ = (char) c;
}
*cp = 0;
/*
* The real work for the match.
*/
if (tnamatch(name)) {
(void) 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.
*/
int
tnchktc(void)
{
char *p, *q;
char tcname[16]; /* name of similar terminal */
char tcbuf[BUFSIZ];
char *holdtbuf = tbuf;
ptrdiff_t l;
p = tbuf + strlen(tbuf) - 2; /* before the last colon */
while (*--p != ':')
if (p < tbuf) {
(void) 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') {
tngetsize(tbuf);
return (1);
}
(void) strcpy(tcname, p+3);
q = tcname;
while (*q && *q != ':')
q++;
*q = 0;
if (++hopcount > MAXHOP) {
(void) write(2, "Infinite tc= loop\n", 18);
return (0);
}
if (tgetent(tcbuf, tcname) != 1) {
hopcount = 0; /* unwind recursion */
return (0);
}
for (q = tcbuf; *q != ':'; q++)
;
l = p - holdtbuf + strlen(q);
if (l > BUFSIZ) {
(void) write(2, "Termcap entry too long\n", 23);
q[BUFSIZ - (p-tbuf)] = 0;
}
(void) strcpy(p, q+1);
tbuf = holdtbuf;
hopcount = 0; /* unwind recursion */
tngetsize(tbuf);
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.
*/
int
tnamatch(char *np)
{
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(char *bp)
{
while (*bp && *bp != ':')
bp++;
if (*bp == ':') {
do {
bp++;
while (isspace(*bp))
bp++;
} while (*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.
*/
int
tgetnum(char *id)
{
int i, base;
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.
*/
int
tgetflag(char *id)
{
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(char *id, char **area)
{
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(char *str, char **area)
{
char *cp;
int c;
char *dp;
int i;
cp = *area;
while (((c = *str++) != 0) && 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++ = (char) c;
}
*cp++ = 0;
str = *area;
*area = cp;
return (str);
}
#include <sys/ioctl.h>
static void
tngetsize(char *bp)
{
struct winsize ws;
char *np, *cp;
if (ioctl(1, TIOCGWINSZ, (char *)&ws) < 0)
return;
if (ws.ws_row == 0 || ws.ws_col == 0 ||
ws.ws_row > 999 || ws.ws_col > 999)
return;
cp = index(bp, ':'); /* find start of description */
bp = rindex(bp, 0); /* find end of description */
np = bp + 15; /* allow enough room for stuff below */
while (bp >= cp) /* move description right 15 chars */
*np-- = *bp--;
bp++; /* bp now points to where ':' used to be */
*bp++ = ':';
*bp++ = 'l';
*bp++ = 'i';
*bp++ = '#';
bp = appendsmalldec(bp, ws.ws_row);
*bp++ = ':';
*bp++ = 'c';
*bp++ = 'o';
*bp++ = '#';
bp = appendsmalldec(bp, ws.ws_col);
*bp++ = ':';
while (bp <= np) /* space fill to start of orig description */
*bp++ = ' ';
}
static char *
appendsmalldec(char *bp, int val)
{
int i;
if ((i = val / 100) != 0) {
*bp++ = '0' + i;
val %= 100;
if (0 == val / 10)
*bp++ = '0'; /* place holder because next test fails */
}
if ((i = val / 10) != 0)
*bp++ = '0' + i;
*bp++ = '0' + val % 10;
return (bp);
}