usr.bin/tip/tip/remcap.c

   1 /*
   2  * Copyright (c) 1983, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  *
  33  * @(#)remcap.c 8.1 (Berkeley) 6/6/93
  34  */
  35
  36 /*
  37  * remcap - routines for dealing with the remote host data base
  38  *
  39  * derived from termcap
  40  */
  41 #include <sys/types.h>
  42 #include <fcntl.h>
  43 #include <ctype.h>
  44 #include <stdlib.h>
  45 #include "pathnames.h"
  46
  47 #ifndef BUFSIZ
  48 #define BUFSIZ          1024
  49 #endif
  50 #define MAXHOP          32              /* max number of tc= indirections */
  51
  52 #define tgetent         rgetent
  53 #define tnchktc         rnchktc
  54 #define tnamatch        rnamatch
  55 #define tgetnum         rgetnum
  56 #define tgetflag        rgetflag
  57 #define tgetstr         rgetstr
  58 #define E_TERMCAP       RM = _PATH_REMOTE
  59 #define V_TERMCAP       "REMOTE"
  60 #define V_TERM          "HOST"
  61
  62 char    *RM;
  63
  64 /*
  65  * termcap - routines for dealing with the terminal capability data base
  66  *
  67  * BUG:         Should use a "last" pointer in tbuf, so that searching
  68  *              for capabilities alphabetically would not be a n**2/2
  69  *              process when large numbers of capabilities are given.
  70  * Note:        If we add a last pointer now we will screw up the
  71  *              tc capability. We really should compile termcap.
  72  *
  73  * Essentially all the work here is scanning and decoding escapes
  74  * in string capabilities.  We don't use stdio because the editor
  75  * doesn't, and because living w/o it is not hard.
  76  */
  77
  78 static  char *tbuf;
  79 static  int hopcount;   /* detect infinite loops in termcap, init 0 */
  80 static  char *tskip();
  81 char    *tgetstr();
  82 static  char *tdecode();
  83 static  char *remotefile;
  84
  85 /*
  86  * Get an entry for terminal name in buffer bp,
  87  * from the termcap file.  Parse is very rudimentary;
  88  * we just notice escaped newlines.
  89  */
  90 tgetent(bp, name)
  91         char *bp, *name;
  92 {
  93         char lbuf[BUFSIZ], *cp, *p;
  94         int rc1, rc2;
  95
  96         remotefile = cp = getenv(V_TERMCAP);
  97         if (cp == (char *)0 || strcmp(cp, _PATH_REMOTE) == 0) {
  98                 remotefile = cp = _PATH_REMOTE;
  99                 return (getent(bp, name, cp));
 100         } else {
 101                 if ((rc1 = getent(bp, name, cp)) != 1)
 102                         *bp = '\0';
 103                 remotefile = cp = _PATH_REMOTE;
 104                 rc2 = getent(lbuf, name, cp);
 105                 if (rc1 != 1 && rc2 != 1)
 106                         return (rc2);
 107                 if (rc2 == 1) {
 108                         p = lbuf;
 109                         if (rc1 == 1)
 110                                 while (*p++ != ':')
 111                                         ;
 112                         if (strlen(bp) + strlen(p) > BUFSIZ) {
 113                                 write(2, "Remcap entry too long\n", 23);
 114                                 return (-1);
 115                         }
 116                         strcat(bp, p);
 117                 }
 118                 tbuf = bp;
 119                 return (1);
 120         }
 121 }
 122
 123 getent(bp, name, cp)
 124         char *bp, *name, *cp;
 125 {
 126         register int c;
 127         register int i = 0, cnt = 0;
 128         char ibuf[BUFSIZ], *cp2;
 129         int tf;
 130
 131         tbuf = bp;
 132         tf = 0;
 133         /*
 134          * TERMCAP can have one of two things in it. It can be the
 135          * name of a file to use instead of /etc/termcap. In this
 136          * case it better start with a "/". Or it can be an entry to
 137          * use so we don't have to read the file. In this case it
 138          * has to already have the newlines crunched out.
 139          */
 140         if (cp && *cp) {
 141                 if (*cp!='/') {
 142                         cp2 = getenv(V_TERM);
 143                         if (cp2 == (char *)0 || strcmp(name,cp2) == 0) {
 144                                 strcpy(bp,cp);
 145                                 return (tnchktc());
 146                         } else
 147                                 tf = open(E_TERMCAP, O_RDONLY);
 148                 } else
 149                         tf = open(RM = cp, O_RDONLY);
 150         }
 151         if (tf == 0)
 152                 tf = open(E_TERMCAP, O_RDONLY);
 153         if (tf < 0)
 154                 return (-1);
 155         for (;;) {
 156                 cp = bp;
 157                 for (;;) {
 158                         if (i == cnt) {
 159                                 cnt = read(tf, ibuf, BUFSIZ);
 160                                 if (cnt <= 0) {
 161                                         close(tf);
 162                                         return (0);
 163                                 }
 164                                 i = 0;
 165                         }
 166                         c = ibuf[i++];
 167                         if (c == '\n') {
 168                                 if (cp > bp && cp[-1] == '\\') {
 169                                         cp--;
 170                                         continue;
 171                                 }
 172                                 break;
 173                         }
 174                         if (cp >= bp+BUFSIZ) {
 175                                 write(2,"Remcap entry too long\n", 23);
 176                                 break;
 177                         } else
 178                                 *cp++ = c;
 179                 }
 180                 *cp = 0;
 181
 182                 /*
 183                  * The real work for the match.
 184                  */
 185                 if (tnamatch(name)) {
 186                         close(tf);
 187                         return (tnchktc());
 188                 }
 189         }
 190 }
 191
 192 /*
 193  * tnchktc: check the last entry, see if it's tc=xxx. If so,
 194  * recursively find xxx and append that entry (minus the names)
 195  * to take the place of the tc=xxx entry. This allows termcap
 196  * entries to say "like an HP2621 but doesn't turn on the labels".
 197  * Note that this works because of the left to right scan.
 198  */
 199 tnchktc()
 200 {
 201         register char *p, *q;
 202         char tcname[16];        /* name of similar terminal */
 203         char tcbuf[BUFSIZ];
 204         char *holdtbuf = tbuf;
 205         int l;
 206         char *cp;
 207
 208         p = tbuf + strlen(tbuf) - 2;    /* before the last colon */
 209         while (*--p != ':')
 210                 if (p<tbuf) {
 211                         write(2, "Bad remcap entry\n", 18);
 212                         return (0);
 213                 }
 214         p++;
 215         /* p now points to beginning of last field */
 216         if (p[0] != 't' || p[1] != 'c')
 217                 return (1);
 218         strcpy(tcname, p+3);
 219         q = tcname;
 220         while (*q && *q != ':')
 221                 q++;
 222         *q = 0;
 223         if (++hopcount > MAXHOP) {
 224                 write(2, "Infinite tc= loop\n", 18);
 225                 return (0);
 226         }
 227         if (getent(tcbuf, tcname, remotefile) != 1) {
 228                 if (strcmp(remotefile, _PATH_REMOTE) == 0)
 229                         return (0);
 230                 else if (getent(tcbuf, tcname, _PATH_REMOTE) != 1)
 231                         return (0);
 232         }
 233         for (q = tcbuf; *q++ != ':'; )
 234                 ;
 235         l = p - holdtbuf + strlen(q);
 236         if (l > BUFSIZ) {
 237                 write(2, "Remcap entry too long\n", 23);
 238                 q[BUFSIZ - (p-holdtbuf)] = 0;
 239         }
 240         strcpy(p, q);
 241         tbuf = holdtbuf;
 242         return (1);
 243 }
 244
 245 /*
 246  * Tnamatch deals with name matching.  The first field of the termcap
 247  * entry is a sequence of names separated by |'s, so we compare
 248  * against each such name.  The normal : terminator after the last
 249  * name (before the first field) stops us.
 250  */
 251 tnamatch(np)
 252         char *np;
 253 {
 254         register char *Np, *Bp;
 255
 256         Bp = tbuf;
 257         if (*Bp == '#')
 258                 return (0);
 259         for (;;) {
 260                 for (Np = np; *Np && *Bp == *Np; Bp++, Np++)
 261                         continue;
 262                 if (*Np == 0 && (*Bp == '|' || *Bp == ':' || *Bp == 0))
 263                         return (1);
 264                 while (*Bp && *Bp != ':' && *Bp != '|')
 265                         Bp++;
 266                 if (*Bp == 0 || *Bp == ':')
 267                         return (0);
 268                 Bp++;
 269         }
 270 }
 271
 272 /*
 273  * Skip to the next field.  Notice that this is very dumb, not
 274  * knowing about \: escapes or any such.  If necessary, :'s can be put
 275  * into the termcap file in octal.
 276  */
 277 static char *
 278 tskip(bp)
 279         register char *bp;
 280 {
 281
 282         while (*bp && *bp != ':')
 283                 bp++;
 284         if (*bp == ':')
 285                 bp++;
 286         return (bp);
 287 }
 288
 289 /*
 290  * Return the (numeric) option id.
 291  * Numeric options look like
 292  *      li#80
 293  * i.e. the option string is separated from the numeric value by
 294  * a # character.  If the option is not found we return -1.
 295  * Note that we handle octal numbers beginning with 0.
 296  */
 297 tgetnum(id)
 298         char *id;
 299 {
 300         register int i, base;
 301         register char *bp = tbuf;
 302
 303         for (;;) {
 304                 bp = tskip(bp);
 305                 if (*bp == 0)
 306                         return (-1);
 307                 if (*bp++ != id[0] || *bp == 0 || *bp++ != id[1])
 308                         continue;
 309                 if (*bp == '@')
 310                         return (-1);
 311                 if (*bp != '#')
 312                         continue;
 313                 bp++;
 314                 base = 10;
 315                 if (*bp == '0')
 316                         base = 8;
 317                 i = 0;
 318                 while (isdigit(*bp))
 319                         i *= base, i += *bp++ - '0';
 320                 return (i);
 321         }
 322 }
 323
 324 /*
 325  * Handle a flag option.
 326  * Flag options are given "naked", i.e. followed by a : or the end
 327  * of the buffer.  Return 1 if we find the option, or 0 if it is
 328  * not given.
 329  */
 330 tgetflag(id)
 331         char *id;
 332 {
 333         register char *bp = tbuf;
 334
 335         for (;;) {
 336                 bp = tskip(bp);
 337                 if (!*bp)
 338                         return (0);
 339                 if (*bp++ == id[0] && *bp != 0 && *bp++ == id[1]) {
 340                         if (!*bp || *bp == ':')
 341                                 return (1);
 342                         else if (*bp == '@')
 343                                 return (0);
 344                 }
 345         }
 346 }
 347
 348 /*
 349  * Get a string valued option.
 350  * These are given as
 351  *      cl=^Z
 352  * Much decoding is done on the strings, and the strings are
 353  * placed in area, which is a ref parameter which is updated.
 354  * No checking on area overflow.
 355  */
 356 char *
 357 tgetstr(id, area)
 358         char *id, **area;
 359 {
 360         register char *bp = tbuf;
 361
 362         for (;;) {
 363                 bp = tskip(bp);
 364                 if (!*bp)
 365                         return (0);
 366                 if (*bp++ != id[0] || *bp == 0 || *bp++ != id[1])
 367                         continue;
 368                 if (*bp == '@')
 369                         return (0);
 370                 if (*bp != '=')
 371                         continue;
 372                 bp++;
 373                 return (tdecode(bp, area));
 374         }
 375 }
 376
 377 /*
 378  * Tdecode does the grung work to decode the
 379  * string capability escapes.
 380  */
 381 static char *
 382 tdecode(str, area)
 383         register char *str;
 384         char **area;
 385 {
 386         register char *cp;
 387         register int c;
 388         register char *dp;
 389         int i;
 390
 391         cp = *area;
 392         while ((c = *str++) && c != ':') {
 393                 switch (c) {
 394
 395                 case '^':
 396                         c = *str++ & 037;
 397                         break;
 398
 399                 case '\\':
 400                         dp = "E\033^^\\\\::n\nr\rt\tb\bf\f";
 401                         c = *str++;
 402 nextc:
 403                         if (*dp++ == c) {
 404                                 c = *dp++;
 405                                 break;
 406                         }
 407                         dp++;
 408                         if (*dp)
 409                                 goto nextc;
 410                         if (isdigit(c)) {
 411                                 c -= '0', i = 2;
 412                                 do
 413                                         c <<= 3, c |= *str++ - '0';
 414                                 while (--i && isdigit(*str));
 415                         }
 416                         break;
 417                 }
 418                 *cp++ = c;
 419         }
 420         *cp++ = 0;
 421         str = *area;
 422         *area = cp;
 423         return (str);
 424 }