OpenSolaris_b135/cmd/tip/remcap.c
/*
* Copyright 2001 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
/*
* Copyright (c) 1983 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"
/*
* remcap - routines for dealing with the remote host data base
*
* derived from termcap
*/
#ifdef USG
#include <sys/types.h>
#include <fcntl.h> /* for O_RDONLY */
#else
#include <sys/file.h> /* for O_RDONLY */
#include <ctype.h>
#endif
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <ctype.h>
#ifndef BUFSIZ
#define BUFSIZ 1024
#endif
#define MAXHOP 32 /* max number of tc= indirections */
#define SYSREMOTE "/etc/remote" /* system remote file */
#define tgetent rgetent
#define tnchktc rnchktc
#define tnamatch rnamatch
#define tgetnum rgetnum
#define tgetflag rgetflag
#define tgetstr rgetstr
#define E_TERMCAP RM = SYSREMOTE
#define V_TERMCAP "REMOTE"
#define V_TERM "HOST"
char *RM;
/*
* 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 *remotefile;
static char *tskip(char *);
static char *tdecode(char *, char **);
char *tgetstr(char *, char **);
int getent(char *, char *, char *, int);
int tnchktc(void);
int tnamatch(char *);
extern void myperm(void);
extern void userperm(void);
/*
* If we use a user specified entry to get the device name,
* we need to open the device as the user.
*/
int trusted_device = 0;
/*
* 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, int len)
{
char lbuf[BUFSIZ], *cp, *p;
int rc1, rc2;
trusted_device = 1;
remotefile = cp = getenv(V_TERMCAP);
if (cp == (char *)0 || strcmp(cp, SYSREMOTE) == 0) {
remotefile = cp = SYSREMOTE;
return (getent(bp, name, cp, len));
} else {
if ((rc1 = getent(bp, name, cp, len)) != 1)
*bp = '\0';
remotefile = cp = SYSREMOTE;
rc2 = getent(lbuf, name, cp, sizeof (lbuf));
if (rc1 != 1 && rc2 != 1)
return (rc2);
if (rc2 == 1) {
p = lbuf;
if (rc1 == 1)
while (*p++ != ':')
;
if (strlen(bp) + strlen(p) >= len) {
(void) write(2, "Remcap entry too long\n", 23);
return (-1);
}
(void) strcat(bp, p);
}
tbuf = bp;
return (1);
}
}
int
getent(char *bp, char *name, char *cp, int len)
{
int c;
int i = 0, cnt = 0;
char ibuf[BUFSIZ], *cp2;
int tf;
int safe = 1; /* reset only when we open the user's $REMOTE */
tbuf = bp;
tf = 0;
/*
* 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 != '/') {
cp2 = getenv(V_TERM);
if (cp2 == (char *)0 || strcmp(name, cp2) == 0) {
if (strstr(cp, "dv=") != 0)
trusted_device = 0;
(void) strncpy(bp, cp, len-1);
bp[len-1] = '\0';
return (tnchktc());
} else
tf = open(E_TERMCAP, O_RDONLY);
} else {
/* open SYSREMOTE as uucp, other files as user */
safe = strcmp(cp, SYSREMOTE) == 0;
if (!safe)
userperm();
tf = open(RM = cp, O_RDONLY);
if (!safe)
myperm();
}
}
if (tf == 0)
tf = open(E_TERMCAP, O_RDONLY);
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+len) {
(void) write(2, "Remcap entry too long\n", 23);
break;
} else
*cp++ = c;
}
*cp = 0;
/*
* The real work for the match.
*/
if (tnamatch(name)) {
/*
* if a dv= entry is obtained from $REMOTE,
* switch off trusted_device status
*/
if (!safe && strstr(bp, "dv=") != 0)
trusted_device = 0;
(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[64]; /* 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) {
(void) write(2, "Bad remcap entry\n", 18);
return (0);
}
p++;
/* p now points to beginning of last field */
if (p[0] != 't' || p[1] != 'c')
return (1);
(void) strlcpy(tcname, p+3, sizeof (tcname));
q = tcname;
while (*q && *q != ':')
q++;
*q = 0;
if (++hopcount > MAXHOP) {
(void) write(2, "Infinite tc= loop\n", 18);
return (0);
}
if (getent(tcbuf, tcname, remotefile, sizeof (tcbuf)) != 1) {
if (strcmp(remotefile, SYSREMOTE) == 0)
return (0);
else if (getent(tcbuf, tcname, SYSREMOTE, sizeof (tcbuf)) != 1)
return (0);
}
for (q = tcbuf; *q++ != ':'; )
;
l = p - holdtbuf + strlen(q);
if (l > BUFSIZ) {
(void) write(2, "Remcap entry too long\n", 23);
q[BUFSIZ - (p-holdtbuf)] = 0;
}
(void) strcpy(p, q);
tbuf = holdtbuf;
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++ = c;
}
*cp++ = 0;
str = *area;
*area = cp;
return (str);
}