usr.bin/vgrind/vgrindefs.c

   1 /*
   2  * Copyright (c) 1980, 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  * @(#)vgrindefs.c      8.1 (Berkeley) 6/6/93
  34  *
  35  * $DragonFly: src/usr.bin/vgrind/vgrindefs.c,v 1.5 2008/10/16 01:52:34 swildner Exp $
  36  */
  37
  38 #define BUFSIZ  1024
  39 #define MAXHOP  32      /* max number of tc= indirections */
  40
  41 #include <ctype.h>
  42 /*
  43  * grindcap - routines for dealing with the language definitions data base
  44  *      (code stolen almost totally from termcap)
  45  *
  46  * BUG:         Should use a "last" pointer in tbuf, so that searching
  47  *              for capabilities alphabetically would not be a n**2/2
  48  *              process when large numbers of capabilities are given.
  49  * Note:        If we add a last pointer now we will screw up the
  50  *              tc capability. We really should compile termcap.
  51  *
  52  * Essentially all the work here is scanning and decoding escapes
  53  * in string capabilities.  We don't use stdio because the editor
  54  * doesn't, and because living w/o it is not hard.
  55  */
  56
  57 static  char *tbuf;
  58 static  char *filename;
  59 static  int hopcount;   /* detect infinite loops in termcap, init 0 */
  60 char    *tskip();
  61 char    *tgetstr();
  62 char    *tdecode();
  63
  64 /*
  65  * Get an entry for terminal name in buffer bp,
  66  * from the termcap file.  Parse is very rudimentary;
  67  * we just notice escaped newlines.
  68  */
  69 int
  70 tgetent(char *bp, char *name, char *file)
  71 {
  72         char *cp;
  73         int c;
  74         int i = 0, cnt = 0;
  75         char ibuf[BUFSIZ];
  76         char *cp2;
  77         int tf;
  78
  79         tbuf = bp;
  80         tf = 0;
  81         filename = file;
  82         tf = open(filename, 0);
  83         if (tf < 0)
  84                 return (-1);
  85         for (;;) {
  86                 cp = bp;
  87                 for (;;) {
  88                         if (i == cnt) {
  89                                 cnt = read(tf, ibuf, BUFSIZ);
  90                                 if (cnt <= 0) {
  91                                         close(tf);
  92                                         return (0);
  93                                 }
  94                                 i = 0;
  95                         }
  96                         c = ibuf[i++];
  97                         if (c == '\n') {
  98                                 if (cp > bp && cp[-1] == '\\'){
  99                                         cp--;
 100                                         continue;
 101                                 }
 102                                 break;
 103                         }
 104                         if (cp >= bp+BUFSIZ) {
 105                                 write(2,"Vgrind entry too long\n", 23);
 106                                 break;
 107                         } else
 108                                 *cp++ = c;
 109                 }
 110                 *cp = 0;
 111
 112                 /*
 113                  * The real work for the match.
 114                  */
 115                 if (tnamatch(name)) {
 116                         close(tf);
 117                         return(tnchktc());
 118                 }
 119         }
 120 }
 121
 122 /*
 123  * tnchktc: check the last entry, see if it's tc=xxx. If so,
 124  * recursively find xxx and append that entry (minus the names)
 125  * to take the place of the tc=xxx entry. This allows termcap
 126  * entries to say "like an HP2621 but doesn't turn on the labels".
 127  * Note that this works because of the left to right scan.
 128  */
 129 int
 130 tnchktc(void)
 131 {
 132         char *p, *q;
 133         char tcname[16];        /* name of similar terminal */
 134         char tcbuf[BUFSIZ];
 135         char *holdtbuf = tbuf;
 136         int l;
 137
 138         p = tbuf + strlen(tbuf) - 2;    /* before the last colon */
 139         while (*--p != ':')
 140                 if (p<tbuf) {
 141                         write(2, "Bad vgrind entry\n", 18);
 142                         return (0);
 143                 }
 144         p++;
 145         /* p now points to beginning of last field */
 146         if (p[0] != 't' || p[1] != 'c')
 147                 return(1);
 148         strcpy(tcname,p+3);
 149         q = tcname;
 150         while (q && *q != ':')
 151                 q++;
 152         *q = 0;
 153         if (++hopcount > MAXHOP) {
 154                 write(2, "Infinite tc= loop\n", 18);
 155                 return (0);
 156         }
 157         if (tgetent(tcbuf, tcname, filename) != 1)
 158                 return(0);
 159         for (q=tcbuf; *q != ':'; q++)
 160                 ;
 161         l = p - holdtbuf + strlen(q);
 162         if (l > BUFSIZ) {
 163                 write(2, "Vgrind entry too long\n", 23);
 164                 q[BUFSIZ - (p-tbuf)] = 0;
 165         }
 166         strcpy(p, q+1);
 167         tbuf = holdtbuf;
 168         return(1);
 169 }
 170
 171 /*
 172  * Tnamatch deals with name matching.  The first field of the termcap
 173  * entry is a sequence of names separated by |'s, so we compare
 174  * against each such name.  The normal : terminator after the last
 175  * name (before the first field) stops us.
 176  */
 177 int
 178 tnamatch(char *np)
 179 {
 180         char *Np, *Bp;
 181
 182         Bp = tbuf;
 183         if (*Bp == '#')
 184                 return(0);
 185         for (;;) {
 186                 for (Np = np; *Np && *Bp == *Np; Bp++, Np++)
 187                         continue;
 188                 if (*Np == 0 && (*Bp == '|' || *Bp == ':' || *Bp == 0))
 189                         return (1);
 190                 while (*Bp && *Bp != ':' && *Bp != '|')
 191                         Bp++;
 192                 if (*Bp == 0 || *Bp == ':')
 193                         return (0);
 194                 Bp++;
 195         }
 196 }
 197
 198 /*
 199  * Skip to the next field.  Notice that this is very dumb, not
 200  * knowing about \: escapes or any such.  If necessary, :'s can be put
 201  * into the termcap file in octal.
 202  */
 203 static char *
 204 tskip(char *bp)
 205 {
 206
 207         while (*bp && *bp != ':')
 208                 bp++;
 209         if (*bp == ':')
 210                 bp++;
 211         return (bp);
 212 }
 213
 214 /*
 215  * Return the (numeric) option id.
 216  * Numeric options look like
 217  *      li#80
 218  * i.e. the option string is separated from the numeric value by
 219  * a # character.  If the option is not found we return -1.
 220  * Note that we handle octal numbers beginning with 0.
 221  */
 222 int
 223 tgetnum(char *id)
 224 {
 225         int i, base;
 226         char *bp = tbuf;
 227
 228         for (;;) {
 229                 bp = tskip(bp);
 230                 if (*bp == 0)
 231                         return (-1);
 232                 if (*bp++ != id[0] || *bp == 0 || *bp++ != id[1])
 233                         continue;
 234                 if (*bp == '@')
 235                         return(-1);
 236                 if (*bp != '#')
 237                         continue;
 238                 bp++;
 239                 base = 10;
 240                 if (*bp == '0')
 241                         base = 8;
 242                 i = 0;
 243                 while (isdigit(*bp))
 244                         i *= base, i += *bp++ - '0';
 245                 return (i);
 246         }
 247 }
 248
 249 /*
 250  * Handle a flag option.
 251  * Flag options are given "naked", i.e. followed by a : or the end
 252  * of the buffer.  Return 1 if we find the option, or 0 if it is
 253  * not given.
 254  */
 255 int
 256 tgetflag(char *id)
 257 {
 258         char *bp = tbuf;
 259
 260         for (;;) {
 261                 bp = tskip(bp);
 262                 if (!*bp)
 263                         return (0);
 264                 if (*bp++ == id[0] && *bp != 0 && *bp++ == id[1]) {
 265                         if (!*bp || *bp == ':')
 266                                 return (1);
 267                         else if (*bp == '@')
 268                                 return(0);
 269                 }
 270         }
 271 }
 272
 273 /*
 274  * Get a string valued option.
 275  * These are given as
 276  *      cl=^Z
 277  * Much decoding is done on the strings, and the strings are
 278  * placed in area, which is a ref parameter which is updated.
 279  * No checking on area overflow.
 280  */
 281 char *
 282 tgetstr(char *id, char **area)
 283 {
 284         char *bp = tbuf;
 285
 286         for (;;) {
 287                 bp = tskip(bp);
 288                 if (!*bp)
 289                         return (0);
 290                 if (*bp++ != id[0] || *bp == 0 || *bp++ != id[1])
 291                         continue;
 292                 if (*bp == '@')
 293                         return(0);
 294                 if (*bp != '=')
 295                         continue;
 296                 bp++;
 297                 return (tdecode(bp, area));
 298         }
 299 }
 300
 301 /*
 302  * Tdecode does the grung work to decode the
 303  * string capability escapes.
 304  */
 305 static char *
 306 tdecode(char *str, char **area)
 307 {
 308         char *cp;
 309         int c;
 310         int i;
 311
 312         cp = *area;
 313         while (c = *str++) {
 314             if (c == ':' && *(cp-1) != '\\')
 315                 break;
 316             *cp++ = c;
 317         }
 318         *cp++ = 0;
 319         str = *area;
 320         *area = cp;
 321         return (str);
 322 }