2.11BSD#431 - /usr/src/libexec/getty/gettytab.c

   1: /*
   2:  * Copyright (c) 1980 Regents of the University of California.
   3:  * All rights reserved.  The Berkeley software License Agreement
   4:  * specifies the terms and conditions for redistribution.
   5:  */
   6: 
   7: #ifndef lint
   8: static char sccsid[] = "@(#)gettytab.c	5.1 (Berkeley) 4/29/85";
   9: #endif not lint
  10: 
  11: #include <ctype.h>
  12: 
  13: #define TABBUFSIZ   512
  14: 
  15: static  char *tbuf;
  16: int hopcount;   /* detect infinite loops in termcap, init 0 */
  17: char    *skip();
  18: char    *getstr();
  19: char    *decode();
  20: 
  21: /*
  22:  * Get an entry for terminal name in buffer bp,
  23:  * from the termcap file.  Parse is very rudimentary;
  24:  * we just notice escaped newlines.
  25:  */
  26: getent(bp, name)
  27:     char *bp, *name;
  28: {
  29:     register char *cp;
  30:     register int c;
  31:     register int i = 0, cnt = 0;
  32:     char ibuf[TABBUFSIZ];
  33:     char *cp2;
  34:     int tf;
  35: 
  36:     tbuf = bp;
  37:     tf = open("/etc/gettytab", 0);
  38:     if (tf < 0)
  39:         return (-1);
  40:     for (;;) {
  41:         cp = bp;
  42:         for (;;) {
  43:             if (i == cnt) {
  44:                 cnt = read(tf, ibuf, TABBUFSIZ);
  45:                 if (cnt <= 0) {
  46:                     close(tf);
  47:                     return (0);
  48:                 }
  49:                 i = 0;
  50:             }
  51:             c = ibuf[i++];
  52:             if (c == '\n') {
  53:                 if (cp > bp && cp[-1] == '\\'){
  54:                     cp--;
  55:                     continue;
  56:                 }
  57:                 break;
  58:             }
  59:             if (cp >= bp+TABBUFSIZ) {
  60:                 write(2,"Gettytab entry too long\n", 24);
  61:                 break;
  62:             } else
  63:                 *cp++ = c;
  64:         }
  65:         *cp = 0;
  66: 
  67:         /*
  68: 		 * The real work for the match.
  69: 		 */
  70:         if (namatch(name)) {
  71:             close(tf);
  72:             return(nchktc());
  73:         }
  74:     }
  75: }
  76: 
  77: /*
  78:  * tnchktc: check the last entry, see if it's tc=xxx. If so,
  79:  * recursively find xxx and append that entry (minus the names)
  80:  * to take the place of the tc=xxx entry. This allows termcap
  81:  * entries to say "like an HP2621 but doesn't turn on the labels".
  82:  * Note that this works because of the left to right scan.
  83:  */
  84: #define MAXHOP  32
  85: nchktc()
  86: {
  87:     register char *p, *q;
  88:     char tcname[16];    /* name of similar terminal */
  89:     char tcbuf[TABBUFSIZ];
  90:     char *holdtbuf = tbuf;
  91:     int l;
  92: 
  93:     p = tbuf + strlen(tbuf) - 2;    /* before the last colon */
  94:     while (*--p != ':')
  95:         if (p<tbuf) {
  96:             write(2, "Bad gettytab entry\n", 19);
  97:             return (0);
  98:         }
  99:     p++;
 100:     /* p now points to beginning of last field */
 101:     if (p[0] != 't' || p[1] != 'c')
 102:         return(1);
 103:     strcpy(tcname,p+3);
 104:     q = tcname;
 105:     while (q && *q != ':')
 106:         q++;
 107:     *q = 0;
 108:     if (++hopcount > MAXHOP) {
 109:         write(2, "Getty: infinite tc= loop\n", 25);
 110:         return (0);
 111:     }
 112:     if (getent(tcbuf, tcname) != 1)
 113:         return(0);
 114:     for (q=tcbuf; *q != ':'; q++)
 115:         ;
 116:     l = p - holdtbuf + strlen(q);
 117:     if (l > TABBUFSIZ) {
 118:         write(2, "Gettytab entry too long\n", 24);
 119:         q[TABBUFSIZ - (p-tbuf)] = 0;
 120:     }
 121:     strcpy(p, q+1);
 122:     tbuf = holdtbuf;
 123:     return(1);
 124: }
 125: 
 126: /*
 127:  * Tnamatch deals with name matching.  The first field of the termcap
 128:  * entry is a sequence of names separated by |'s, so we compare
 129:  * against each such name.  The normal : terminator after the last
 130:  * name (before the first field) stops us.
 131:  */
 132: namatch(np)
 133:     char *np;
 134: {
 135:     register char *Np, *Bp;
 136: 
 137:     Bp = tbuf;
 138:     if (*Bp == '#')
 139:         return(0);
 140:     for (;;) {
 141:         for (Np = np; *Np && *Bp == *Np; Bp++, Np++)
 142:             continue;
 143:         if (*Np == 0 && (*Bp == '|' || *Bp == ':' || *Bp == 0))
 144:             return (1);
 145:         while (*Bp && *Bp != ':' && *Bp != '|')
 146:             Bp++;
 147:         if (*Bp == 0 || *Bp == ':')
 148:             return (0);
 149:         Bp++;
 150:     }
 151: }
 152: 
 153: /*
 154:  * Skip to the next field.  Notice that this is very dumb, not
 155:  * knowing about \: escapes or any such.  If necessary, :'s can be put
 156:  * into the termcap file in octal.
 157:  */
 158: static char *
 159: skip(bp)
 160:     register char *bp;
 161: {
 162: 
 163:     while (*bp && *bp != ':')
 164:         bp++;
 165:     while (*bp == ':')
 166:         bp++;
 167:     return (bp);
 168: }
 169: 
 170: /*
 171:  * Return the (numeric) option id.
 172:  * Numeric options look like
 173:  *	li#80
 174:  * i.e. the option string is separated from the numeric value by
 175:  * a # character.  If the option is not found we return -1.
 176:  * Note that we handle octal numbers beginning with 0.
 177:  */
 178: long
 179: getnum(id)
 180:     char *id;
 181: {
 182:     register long i, base;
 183:     register char *bp = tbuf;
 184: 
 185:     for (;;) {
 186:         bp = skip(bp);
 187:         if (*bp == 0)
 188:             return (-1);
 189:         if (*bp++ != id[0] || *bp == 0 || *bp++ != id[1])
 190:             continue;
 191:         if (*bp == '@')
 192:             return(-1);
 193:         if (*bp != '#')
 194:             continue;
 195:         bp++;
 196:         base = 10;
 197:         if (*bp == '0')
 198:             base = 8;
 199:         i = 0;
 200:         while (isdigit(*bp))
 201:             i *= base, i += *bp++ - '0';
 202:         return (i);
 203:     }
 204: }
 205: 
 206: /*
 207:  * Handle a flag option.
 208:  * Flag options are given "naked", i.e. followed by a : or the end
 209:  * of the buffer.  Return 1 if we find the option, or 0 if it is
 210:  * not given.
 211:  */
 212: getflag(id)
 213:     char *id;
 214: {
 215:     register char *bp = tbuf;
 216: 
 217:     for (;;) {
 218:         bp = skip(bp);
 219:         if (!*bp)
 220:             return (-1);
 221:         if (*bp++ == id[0] && *bp != 0 && *bp++ == id[1]) {
 222:             if (!*bp || *bp == ':')
 223:                 return (1);
 224:             else if (*bp == '!')
 225:                 return (0);
 226:             else if (*bp == '@')
 227:                 return(-1);
 228:         }
 229:     }
 230: }
 231: 
 232: /*
 233:  * Get a string valued option.
 234:  * These are given as
 235:  *	cl=^Z
 236:  * Much decoding is done on the strings, and the strings are
 237:  * placed in area, which is a ref parameter which is updated.
 238:  * No checking on area overflow.
 239:  */
 240: char *
 241: getstr(id, area)
 242:     char *id, **area;
 243: {
 244:     register char *bp = tbuf;
 245: 
 246:     for (;;) {
 247:         bp = skip(bp);
 248:         if (!*bp)
 249:             return (0);
 250:         if (*bp++ != id[0] || *bp == 0 || *bp++ != id[1])
 251:             continue;
 252:         if (*bp == '@')
 253:             return(0);
 254:         if (*bp != '=')
 255:             continue;
 256:         bp++;
 257:         return (decode(bp, area));
 258:     }
 259: }
 260: 
 261: /*
 262:  * Tdecode does the grung work to decode the
 263:  * string capability escapes.
 264:  */
 265: static char *
 266: decode(str, area)
 267:     register char *str;
 268:     char **area;
 269: {
 270:     register char *cp;
 271:     register int c;
 272:     register char *dp;
 273:     int i;
 274: 
 275:     cp = *area;
 276:     while ((c = *str++) && c != ':') {
 277:         switch (c) {
 278: 
 279:         case '^':
 280:             c = *str++ & 037;
 281:             break;
 282: 
 283:         case '\\':
 284:             dp = "E\033^^\\\\::n\nr\rt\tb\bf\f";
 285:             c = *str++;
 286: nextc:
 287:             if (*dp++ == c) {
 288:                 c = *dp++;
 289:                 break;
 290:             }
 291:             dp++;
 292:             if (*dp)
 293:                 goto nextc;
 294:             if (isdigit(c)) {
 295:                 c -= '0', i = 2;
 296:                 do
 297:                     c <<= 3, c |= *str++ - '0';
 298:                 while (--i && isdigit(*str));
 299:             }
 300:             break;
 301:         }
 302:         *cp++ = c;
 303:     }
 304:     *cp++ = 0;
 305:     str = *area;
 306:     *area = cp;
 307:     return (str);
 308: }

Defined functions

Defined variables

Defined macros