freebsd-dev/lib/libtermcap/termcap.c
Peter Wemm a987686543 s/geteid/geteuid/ - it's lucky I have a large supply of left-over pointy
hats from Tristan's last birthday party. :-]
1997-11-29 11:39:31 +00:00

306 lines
8.3 KiB
C

/*
* Copyright (c) 1980, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifndef lint
static char sccsid[] = "@(#)termcap.c 8.1 (Berkeley) 6/4/93";
#endif /* not lint */
#define PBUFSIZ 512 /* max length of filename path */
#define PVECSIZ 32 /* max number of names in path */
#define TBUFSIZ 1024 /* max length of tgetent buffer */
#include <stdio.h>
#include <ctype.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <termios.h>
#include <signal.h>
#include <errno.h>
#include <sys/syscall.h>
#include "termcap.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; /* termcap buffer */
static int use_issetugid = 1; /* 0 = not present, 1 = try it, 2 = exists */
/*
* Get an entry for terminal name in buffer bp from the termcap file.
*/
int
tgetent(char *bp, const char *name)
{
register char *p;
register char *cp;
char *dummy;
char **fname;
char *home;
int i;
char pathbuf[PBUFSIZ]; /* holds raw path of filenames */
char *pathvec[PVECSIZ]; /* to point to names in pathbuf */
char **pvec; /* holds usable tail of path vector */
char *termpath;
struct termios tty;
dummy = NULL;
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 */
strncpy(pathbuf, home, PBUFSIZ - 1); /* $HOME first */
pathbuf[PBUFSIZ - 2] = '\0'; /* -2 because we add a slash */
p += strlen(pathbuf); /* path, looking in */
*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 */
pathbuf[PBUFSIZ - 1] = '\0';
#ifdef SYS_issetugid
/*
* This stuff is to try and detect the presence of the issetugid()
* syscall without breaking dynamic linking during compiles.. Sigh.
*/
othersyscall:
if (use_issetugid) {
struct sigaction sa, osa;
int sigsys_installed = 0;
int unsafe;
if (use_issetugid == 1) {
bzero(&sa, sizeof(sa));
sa.sa_handler = SIG_IGN;
if (sigaction(SIGSYS, &sa, &osa) >= 0)
sigsys_installed = 1;
}
errno = 0;
unsafe = syscall(SYS_issetugid);
if (sigsys_installed == 1) {
int oerrno = errno;
sigaction(SIGSYS, &osa, NULL);
errno = oerrno;
}
if (errno == ENOSYS || errno == EINVAL) {
use_issetugid = 0;
goto othersyscall;
} else if (sigsys_installed == 1)
sigsys_installed = 2;
if (unsafe)
strcpy(pathbuf, _PATH_DEF_SEC);
} else
#endif /* SYS_issetugid */
/* issetugid() not in kernel or undefined - try second best */
if (getuid() != geteuid() || getgid() != getegid())
strcpy(pathbuf, _PATH_DEF_SEC);
*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 != '/')
if (cgetset(cp) < 0)
return(-2);
i = cgetent(&dummy, pathvec, (char *)name);
if (i == 0) {
char *pd, *ps, *tok, *s, *tcs;
size_t len;
pd = bp;
ps = dummy;
if ((tok = strchr(ps, ':')) == NULL) {
len = strlen(ps);
if (len >= TBUFSIZ)
i = -1;
else
strcpy(pd, ps);
goto done;
}
len = tok - ps + 1;
if (pd + len + 1 - bp >= TBUFSIZ) {
i = -1;
goto done;
}
memcpy(pd, ps, len);
ps += len;
pd += len;
*pd = '\0';
tcs = pd - 1;
for (;;) {
while ((tok = strsep(&ps, ":")) != NULL &&
(*tok == '\0' || *tok == '\\' || !isgraph(*tok)))
;
if (tok == NULL)
break;
for (s = tcs; s != NULL && s[1] != '\0'; s = strchr(s, ':')) {
s++;
if (s[0] == tok[0] && s[1] == tok[1])
goto skip_it;
}
len = strlen(tok);
if (pd + len + 1 - bp >= TBUFSIZ) {
i = -1;
break;
}
memcpy(pd, tok, len);
pd += len;
*pd++ = ':';
*pd = '\0';
skip_it: ;
}
}
done:
if ( i == 0
&& ( tcgetattr(STDERR_FILENO, &tty) != -1
|| tcgetattr(STDOUT_FILENO, &tty) != -1
)
)
__set_ospeed(cfgetospeed(&tty));
if (dummy)
free(dummy);
/* no tc reference loop return code in libterm XXX */
if (i == -3)
return(-1);
return(i + 1);
}
/*
* 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(const char *id)
{
long num;
if (cgetnum(tbuf, (char *)id, &num) == 0)
return(num);
else
return(-1);
}
/*
* 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(const char *id)
{
return(cgetcap(tbuf, (char *)id, ':') != NULL);
}
/*
* 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(const char *id, char **area)
{
char ids[3];
char *s;
int i;
/*
* XXX
* This is for all the boneheaded programs that relied on tgetstr
* to look only at the first 2 characters of the string passed...
*/
*ids = *id;
ids[1] = id[1];
ids[2] = '\0';
if ((i = cgetstr(tbuf, ids, &s)) < 0)
return NULL;
strcpy(*area, s);
*area += i + 1;
return(s);
}