cmd/captoinfo/otermcap.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*  Copyright (c) 1988 AT&T */
/*    All Rights Reserved   */

#pragma ident   "%Z%%M% %I% %E% SMI"

/* Copyright (c) 1979 Regents of the University of California   */
/* Modified to:                         */
/* 1) remember the name of the first tc= parameter      */
/*  encountered during parsing.             */
/* 2) handle multiple invocations of tgetent().         */
/* 3) tskip() is now available outside of the library.      */
/* 4) remember $TERM name for error messages.           */
/* 5) have a larger buffer.                 */
/* 6) really fix the bug that 5) got around. This fix by    */
/*      Marion Hakanson, orstcs!hakanson        */


#include "otermcap.h"
#define MAXHOP  32  /* max number of tc= indirections */

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/uio.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>

#include <signal.h>   /* use this file to determine if this is SVR4.0 system */
#ifdef SIGSTOP /* SVR4.0 and beyond */
#define E_TERMCAP "/usr/share/lib/termcap"
#else
#define E_TERMCAP "/etc/termcap"
#endif

/*
 * 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 */
char    *tskip(char *);
char    *otgetstr(char *, char **);

/* Tony Hansen */
int TLHtcfound = 0;
char    TLHtcname[16];
static  char *termname;

static int _tgetent(char *, char *);
static int otnchktc(void);
static char *tdecode(char *, char **);
static int otnamatch(char *);
/*
 * Get an entry for terminal name in buffer bp,
 * from the termcap file.  Parse is very rudimentary;
 * we just notice escaped newlines.
 */
int
otgetent(char *bp, char *name)
{
    /* Tony Hansen */
    int ret;
    TLHtcfound = 0;
    hopcount = 0;
    termname = name;
    ret = _tgetent(bp, name);
    /*
     * There is some sort of bug in the check way down below to prevent
     * buffer overflow. I really don't want to track it down, so I
     * upped the standard buffer size and check here to see if the created
     * buffer is larger than the old buffer size.
     */
    if (strlen(bp) >= 1024)
        (void) fprintf(stderr,
            "tgetent(): TERM=%s: Termcap entry is too long.\n",
            termname);
    return (ret);
}

static int
_tgetent(char *bp, char *name)
{
    char *cp;
    int c;
    int i = 0, cnt = 0;
    char ibuf[TBUFSIZE];
    char *cp2;
    int tf;

    tbuf = bp;
    tf = 0;
#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 != '/') {
            cp2 = getenv("TERM");
            if (cp2 == (char *)0 || strcmp(name, cp2) == 0) {
                (void) strcpy(bp, cp);
                return (otnchktc());
            } else {
                tf = open(E_TERMCAP, 0);
            }
        } else
            tf = open(cp, 0);
    }
    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, TBUFSIZE);
                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 + TBUFSIZE) {
                (void) fprintf(stderr, "tgetent(): TERM=%s: "
                    "Termcap entry too long\n", termname);
                break;
            } else
                *cp++ = c;
        }
        *cp = 0;

        /*
         * The real work for the match.
         */
        if (otnamatch(name)) {
            (void) close(tf);
            return (otnchktc());
        }
    }
}

/*
 * otnchktc: 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.
 */
static int
otnchktc(void)
{
    char *p, *q;
#define TERMNAMESIZE 16
    char tcname[TERMNAMESIZE];  /* name of similar terminal */
    char tcbuf[TBUFSIZE];
    char *holdtbuf = tbuf;
    int l;

    p = tbuf + strlen(tbuf) - 2;    /* before the last colon */
    while (*--p != ':')
        if (p < tbuf) {
            (void) fprintf(stderr, "tnchktc(): TERM=%s: Bad "
                "termcap entry\n", termname);
            return (0);
        }
    p++;
    /* p now points to beginning of last field */
    if (p[0] != 't' || p[1] != 'c')
        return (1);
    (void) strncpy(tcname, p + 3, TERMNAMESIZE);    /* TLH */
    q = tcname;
    while (*q && *q != ':')
        q++;
    *q = 0;
    if (++hopcount > MAXHOP) {
        (void) fprintf(stderr, "tnchktc(): TERM=%s: Infinite tc= "
            "loop\n", termname);
        return (0);
    }
    if (_tgetent(tcbuf, tcname) != 1)
        return (0);
    /* Tony Hansen */
    TLHtcfound++;
    (void) strcpy(TLHtcname, tcname);

    for (q = tcbuf; *q != ':'; q++)
        ;
    l = p - holdtbuf + strlen(q);
    if (l > TBUFSIZE) {
        (void) fprintf(stderr, "tnchktc(): TERM=%s: Termcap entry "
            "too long\n", termname);
        q[TBUFSIZE - (p - holdtbuf)] = 0;
    }
    (void) strcpy(p, q + 1);
    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.
 */
static int
otnamatch(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.
 */
char *
tskip(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.
 */
int
otgetnum(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
otgetflag(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 *
otgetstr(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);
}