2.9BSD - /usr/src/ucb/vgrind/vgrindefs.c

   1: /* Copyright (c) 1979 Regents of the University of California */
   2: #define BUFSIZ  1024
   3: #define MAXHOP  32  /* max number of tc= indirections */
   4: 
   5: #include <ctype.h>
   6: #include "local/uparm.h"
   7: /*
   8:  * grindcap - routines for dealing with the language definitions data base
   9:  *	(code stolen almost totally from termcap)
  10:  *
  11:  * BUG:		Should use a "last" pointer in tbuf, so that searching
  12:  *		for capabilities alphabetically would not be a n**2/2
  13:  *		process when large numbers of capabilities are given.
  14:  * Note:	If we add a last pointer now we will screw up the
  15:  *		tc capability. We really should compile termcap.
  16:  *
  17:  * Essentially all the work here is scanning and decoding escapes
  18:  * in string capabilities.  We don't use stdio because the editor
  19:  * doesn't, and because living w/o it is not hard.
  20:  */
  21: 
  22: static  char *tbuf;
  23: static  int hopcount;   /* detect infinite loops in termcap, init 0 */
  24: char    *tskip();
  25: char    *tgetstr();
  26: char    *tdecode();
  27: char    *getenv();
  28: 
  29: /*
  30:  * Get an entry for terminal name in buffer bp,
  31:  * from the termcap file.  Parse is very rudimentary;
  32:  * we just notice escaped newlines.
  33:  */
  34: tgetent(bp, name, filename)
  35:     char *bp, *name, *filename;
  36: {
  37:     register char *cp;
  38:     register int c;
  39:     register int i = 0, cnt = 0;
  40:     char ibuf[BUFSIZ];
  41:     char *cp2;
  42:     int tf;
  43: 
  44:     tbuf = bp;
  45:     tf = 0;
  46:     tf = open(filename, 0);
  47:     if (tf < 0)
  48:         return (-1);
  49:     for (;;) {
  50:         cp = bp;
  51:         for (;;) {
  52:             if (i == cnt) {
  53:                 cnt = read(tf, ibuf, BUFSIZ);
  54:                 if (cnt <= 0) {
  55:                     close(tf);
  56:                     return (0);
  57:                 }
  58:                 i = 0;
  59:             }
  60:             c = ibuf[i++];
  61:             if (c == '\n') {
  62:                 if (cp > bp && cp[-1] == '\\'){
  63:                     cp--;
  64:                     continue;
  65:                 }
  66:                 break;
  67:             }
  68:             if (cp >= bp+BUFSIZ) {
  69:                 write(2,"Vgrind entry too long\n", 23);
  70:                 break;
  71:             } else
  72:                 *cp++ = c;
  73:         }
  74:         *cp = 0;
  75: 
  76:         /*
  77: 		 * The real work for the match.
  78: 		 */
  79:         if (tnamatch(name)) {
  80:             close(tf);
  81:             return(tnchktc());
  82:         }
  83:     }
  84: }
  85: 
  86: /*
  87:  * tnchktc: check the last entry, see if it's tc=xxx. If so,
  88:  * recursively find xxx and append that entry (minus the names)
  89:  * to take the place of the tc=xxx entry. This allows termcap
  90:  * entries to say "like an HP2621 but doesn't turn on the labels".
  91:  * Note that this works because of the left to right scan.
  92:  */
  93: tnchktc()
  94: {
  95:     register char *p, *q;
  96:     char tcname[16];    /* name of similar terminal */
  97:     char tcbuf[BUFSIZ];
  98:     char *holdtbuf = tbuf;
  99:     int l;
 100: 
 101:     p = tbuf + strlen(tbuf) - 2;    /* before the last colon */
 102:     while (*--p != ':')
 103:         if (p<tbuf) {
 104:             write(2, "Bad vgrind entry\n", 18);
 105:             return (0);
 106:         }
 107:     p++;
 108:     /* p now points to beginning of last field */
 109:     if (p[0] != 't' || p[1] != 'c')
 110:         return(1);
 111:     strcpy(tcname,p+3);
 112:     q = tcname;
 113:     while (q && *q != ':')
 114:         q++;
 115:     *q = 0;
 116:     if (++hopcount > MAXHOP) {
 117:         write(2, "Infinite tc= loop\n", 18);
 118:         return (0);
 119:     }
 120:     if (tgetent(tcbuf, tcname) != 1)
 121:         return(0);
 122:     for (q=tcbuf; *q != ':'; q++)
 123:         ;
 124:     l = p - holdtbuf + strlen(q);
 125:     if (l > BUFSIZ) {
 126:         write(2, "Vgrind entry too long\n", 23);
 127:         q[BUFSIZ - (p-tbuf)] = 0;
 128:     }
 129:     strcpy(p, q+1);
 130:     tbuf = holdtbuf;
 131:     return(1);
 132: }
 133: 
 134: /*
 135:  * Tnamatch deals with name matching.  The first field of the termcap
 136:  * entry is a sequence of names separated by |'s, so we compare
 137:  * against each such name.  The normal : terminator after the last
 138:  * name (before the first field) stops us.
 139:  */
 140: tnamatch(np)
 141:     char *np;
 142: {
 143:     register char *Np, *Bp;
 144: 
 145:     Bp = tbuf;
 146:     if (*Bp == '#')
 147:         return(0);
 148:     for (;;) {
 149:         for (Np = np; *Np && *Bp == *Np; Bp++, Np++)
 150:             continue;
 151:         if (*Np == 0 && (*Bp == '|' || *Bp == ':' || *Bp == 0))
 152:             return (1);
 153:         while (*Bp && *Bp != ':' && *Bp != '|')
 154:             Bp++;
 155:         if (*Bp == 0 || *Bp == ':')
 156:             return (0);
 157:         Bp++;
 158:     }
 159: }
 160: 
 161: /*
 162:  * Skip to the next field.  Notice that this is very dumb, not
 163:  * knowing about \: escapes or any such.  If necessary, :'s can be put
 164:  * into the termcap file in octal.
 165:  */
 166: static char *
 167: tskip(bp)
 168:     register char *bp;
 169: {
 170: 
 171:     while (*bp && *bp != ':')
 172:         bp++;
 173:     if (*bp == ':')
 174:         bp++;
 175:     return (bp);
 176: }
 177: 
 178: /*
 179:  * Return the (numeric) option id.
 180:  * Numeric options look like
 181:  *	li#80
 182:  * i.e. the option string is separated from the numeric value by
 183:  * a # character.  If the option is not found we return -1.
 184:  * Note that we handle octal numbers beginning with 0.
 185:  */
 186: tgetnum(id)
 187:     char *id;
 188: {
 189:     register int i, base;
 190:     register char *bp = tbuf;
 191: 
 192:     for (;;) {
 193:         bp = tskip(bp);
 194:         if (*bp == 0)
 195:             return (-1);
 196:         if (*bp++ != id[0] || *bp == 0 || *bp++ != id[1])
 197:             continue;
 198:         if (*bp == '@')
 199:             return(-1);
 200:         if (*bp != '#')
 201:             continue;
 202:         bp++;
 203:         base = 10;
 204:         if (*bp == '0')
 205:             base = 8;
 206:         i = 0;
 207:         while (isdigit(*bp))
 208:             i *= base, i += *bp++ - '0';
 209:         return (i);
 210:     }
 211: }
 212: 
 213: /*
 214:  * Handle a flag option.
 215:  * Flag options are given "naked", i.e. followed by a : or the end
 216:  * of the buffer.  Return 1 if we find the option, or 0 if it is
 217:  * not given.
 218:  */
 219: tgetflag(id)
 220:     char *id;
 221: {
 222:     register char *bp = tbuf;
 223: 
 224:     for (;;) {
 225:         bp = tskip(bp);
 226:         if (!*bp)
 227:             return (0);
 228:         if (*bp++ == id[0] && *bp != 0 && *bp++ == id[1]) {
 229:             if (!*bp || *bp == ':')
 230:                 return (1);
 231:             else if (*bp == '@')
 232:                 return(0);
 233:         }
 234:     }
 235: }
 236: 
 237: /*
 238:  * Get a string valued option.
 239:  * These are given as
 240:  *	cl=^Z
 241:  * Much decoding is done on the strings, and the strings are
 242:  * placed in area, which is a ref parameter which is updated.
 243:  * No checking on area overflow.
 244:  */
 245: char *
 246: tgetstr(id, area)
 247:     char *id, **area;
 248: {
 249:     register char *bp = tbuf;
 250: 
 251:     for (;;) {
 252:         bp = tskip(bp);
 253:         if (!*bp)
 254:             return (0);
 255:         if (*bp++ != id[0] || *bp == 0 || *bp++ != id[1])
 256:             continue;
 257:         if (*bp == '@')
 258:             return(0);
 259:         if (*bp != '=')
 260:             continue;
 261:         bp++;
 262:         return (tdecode(bp, area));
 263:     }
 264: }
 265: 
 266: /*
 267:  * Tdecode does the grung work to decode the
 268:  * string capability escapes.
 269:  */
 270: static char *
 271: tdecode(str, area)
 272:     register char *str;
 273:     char **area;
 274: {
 275:     register char *cp;
 276:     register int c;
 277:     int i;
 278: 
 279:     cp = *area;
 280:     while (c = *str++) {
 281:         if (c == ':' && *(cp-1) != '\\')
 282:         break;
 283:         *cp++ = c;
 284:     }
 285:     *cp++ = 0;
 286:     str = *area;
 287:     *area = cp;
 288:     return (str);
 289: }

Defined functions

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Defined macros