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. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  * @(#)vgrindefs.c      8.1 (Berkeley) 6/6/93
  30  *
  31  * $DragonFly: src/usr.bin/vgrind/vgrindefs.c,v 1.5 2008/10/16 01:52:34 swildner Exp $
  32  */
  33
  34 #define BUFSIZ  1024
  35 #define MAXHOP  32      /* max number of tc= indirections */
  36
  37 #include <ctype.h>
  38 /*
  39  * grindcap - routines for dealing with the language definitions data base
  40  *      (code stolen almost totally from termcap)
  41  *
  42  * BUG:         Should use a "last" pointer in tbuf, so that searching
  43  *              for capabilities alphabetically would not be a n**2/2
  44  *              process when large numbers of capabilities are given.
  45  * Note:        If we add a last pointer now we will screw up the
  46  *              tc capability. We really should compile termcap.
  47  *
  48  * Essentially all the work here is scanning and decoding escapes
  49  * in string capabilities.  We don't use stdio because the editor
  50  * doesn't, and because living w/o it is not hard.
  51  */
  52
  53 static  char *tbuf;
  54 static  char *filename;
  55 static  int hopcount;   /* detect infinite loops in termcap, init 0 */
  56 char    *tskip();
  57 char    *tgetstr();
  58 char    *tdecode();
  59
  60 /*
  61  * Get an entry for terminal name in buffer bp,
  62  * from the termcap file.  Parse is very rudimentary;
  63  * we just notice escaped newlines.
  64  */
  65 int
  66 tgetent(char *bp, char *name, char *file)
  67 {
  68         char *cp;
  69         int c;
  70         int i = 0, cnt = 0;
  71         char ibuf[BUFSIZ];
  72         char *cp2;
  73         int tf;
  74
  75         tbuf = bp;
  76         tf = 0;
  77         filename = file;
  78         tf = open(filename, 0);
  79         if (tf < 0)
  80                 return (-1);
  81         for (;;) {
  82                 cp = bp;
  83                 for (;;) {
  84                         if (i == cnt) {
  85                                 cnt = read(tf, ibuf, BUFSIZ);
  86                                 if (cnt <= 0) {
  87                                         close(tf);
  88                                         return (0);
  89                                 }
  90                                 i = 0;
  91                         }
  92                         c = ibuf[i++];
  93                         if (c == '\n') {
  94                                 if (cp > bp && cp[-1] == '\\'){
  95                                         cp--;
  96                                         continue;
  97                                 }
  98                                 break;
  99                         }
 100                         if (cp >= bp+BUFSIZ) {
 101                                 write(2,"Vgrind entry too long\n", 23);
 102                                 break;
 103                         } else
 104                                 *cp++ = c;
 105                 }
 106                 *cp = 0;
 107
 108                 /*
 109                  * The real work for the match.
 110                  */
 111                 if (tnamatch(name)) {
 112                         close(tf);
 113                         return(tnchktc());
 114                 }
 115         }
 116 }
 117
 118 /*
 119  * tnchktc: check the last entry, see if it's tc=xxx. If so,
 120  * recursively find xxx and append that entry (minus the names)
 121  * to take the place of the tc=xxx entry. This allows termcap
 122  * entries to say "like an HP2621 but doesn't turn on the labels".
 123  * Note that this works because of the left to right scan.
 124  */
 125 int
 126 tnchktc(void)
 127 {
 128         char *p, *q;
 129         char tcname[16];        /* name of similar terminal */
 130         char tcbuf[BUFSIZ];
 131         char *holdtbuf = tbuf;
 132         int l;
 133
 134         p = tbuf + strlen(tbuf) - 2;    /* before the last colon */
 135         while (*--p != ':')
 136                 if (p<tbuf) {
 137                         write(2, "Bad vgrind entry\n", 18);
 138                         return (0);
 139                 }
 140         p++;
 141         /* p now points to beginning of last field */
 142         if (p[0] != 't' || p[1] != 'c')
 143                 return(1);
 144         strcpy(tcname,p+3);
 145         q = tcname;
 146         while (q && *q != ':')
 147                 q++;
 148         *q = 0;
 149         if (++hopcount > MAXHOP) {
 150                 write(2, "Infinite tc= loop\n", 18);
 151                 return (0);
 152         }
 153         if (tgetent(tcbuf, tcname, filename) != 1)
 154                 return(0);
 155         for (q=tcbuf; *q != ':'; q++)
 156                 ;
 157         l = p - holdtbuf + strlen(q);
 158         if (l > BUFSIZ) {
 159                 write(2, "Vgrind entry too long\n", 23);
 160                 q[BUFSIZ - (p-tbuf)] = 0;
 161         }
 162         strcpy(p, q+1);
 163         tbuf = holdtbuf;
 164         return(1);
 165 }
 166
 167 /*
 168  * Tnamatch deals with name matching.  The first field of the termcap
 169  * entry is a sequence of names separated by |'s, so we compare
 170  * against each such name.  The normal : terminator after the last
 171  * name (before the first field) stops us.
 172  */
 173 int
 174 tnamatch(char *np)
 175 {
 176         char *Np, *Bp;
 177
 178         Bp = tbuf;
 179         if (*Bp == '#')
 180                 return(0);
 181         for (;;) {
 182                 for (Np = np; *Np && *Bp == *Np; Bp++, Np++)
 183                         continue;
 184                 if (*Np == 0 && (*Bp == '|' || *Bp == ':' || *Bp == 0))
 185                         return (1);
 186                 while (*Bp && *Bp != ':' && *Bp != '|')
 187                         Bp++;
 188                 if (*Bp == 0 || *Bp == ':')
 189                         return (0);
 190                 Bp++;
 191         }
 192 }
 193
 194 /*
 195  * Skip to the next field.  Notice that this is very dumb, not
 196  * knowing about \: escapes or any such.  If necessary, :'s can be put
 197  * into the termcap file in octal.
 198  */
 199 static char *
 200 tskip(char *bp)
 201 {
 202
 203         while (*bp && *bp != ':')
 204                 bp++;
 205         if (*bp == ':')
 206                 bp++;
 207         return (bp);
 208 }
 209
 210 /*
 211  * Return the (numeric) option id.
 212  * Numeric options look like
 213  *      li#80
 214  * i.e. the option string is separated from the numeric value by
 215  * a # character.  If the option is not found we return -1.
 216  * Note that we handle octal numbers beginning with 0.
 217  */
 218 int
 219 tgetnum(char *id)
 220 {
 221         int i, base;
 222         char *bp = tbuf;
 223
 224         for (;;) {
 225                 bp = tskip(bp);
 226                 if (*bp == 0)
 227                         return (-1);
 228                 if (*bp++ != id[0] || *bp == 0 || *bp++ != id[1])
 229                         continue;
 230                 if (*bp == '@')
 231                         return(-1);
 232                 if (*bp != '#')
 233                         continue;
 234                 bp++;
 235                 base = 10;
 236                 if (*bp == '0')
 237                         base = 8;
 238                 i = 0;
 239                 while (isdigit(*bp))
 240                         i *= base, i += *bp++ - '0';
 241                 return (i);
 242         }
 243 }
 244
 245 /*
 246  * Handle a flag option.
 247  * Flag options are given "naked", i.e. followed by a : or the end
 248  * of the buffer.  Return 1 if we find the option, or 0 if it is
 249  * not given.
 250  */
 251 int
 252 tgetflag(char *id)
 253 {
 254         char *bp = tbuf;
 255
 256         for (;;) {
 257                 bp = tskip(bp);
 258                 if (!*bp)
 259                         return (0);
 260                 if (*bp++ == id[0] && *bp != 0 && *bp++ == id[1]) {
 261                         if (!*bp || *bp == ':')
 262                                 return (1);
 263                         else if (*bp == '@')
 264                                 return(0);
 265                 }
 266         }
 267 }
 268
 269 /*
 270  * Get a string valued option.
 271  * These are given as
 272  *      cl=^Z
 273  * Much decoding is done on the strings, and the strings are
 274  * placed in area, which is a ref parameter which is updated.
 275  * No checking on area overflow.
 276  */
 277 char *
 278 tgetstr(char *id, char **area)
 279 {
 280         char *bp = tbuf;
 281
 282         for (;;) {
 283                 bp = tskip(bp);
 284                 if (!*bp)
 285                         return (0);
 286                 if (*bp++ != id[0] || *bp == 0 || *bp++ != id[1])
 287                         continue;
 288                 if (*bp == '@')
 289                         return(0);
 290                 if (*bp != '=')
 291                         continue;
 292                 bp++;
 293                 return (tdecode(bp, area));
 294         }
 295 }
 296
 297 /*
 298  * Tdecode does the grung work to decode the
 299  * string capability escapes.
 300  */
 301 static char *
 302 tdecode(char *str, char **area)
 303 {
 304         char *cp;
 305         int c;
 306         int i;
 307
 308         cp = *area;
 309         while (c = *str++) {
 310             if (c == ':' && *(cp-1) != '\\')
 311                 break;
 312             *cp++ = c;
 313         }
 314         *cp++ = 0;
 315         str = *area;
 316         *area = cp;
 317         return (str);
 318 }