usr/src/cmd/troff/n8.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  */
  22 /*
  23  * Copyright 2003 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26
  27 /*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
  28 /*        All Rights Reserved   */
  29
  30 /*
  31  * University Copyright- Copyright (c) 1982, 1986, 1988
  32  * The Regents of the University of California
  33  * All Rights Reserved
  34  *
  35  * University Acknowledgment- Portions of this document are derived from
  36  * software developed by the University of California, Berkeley, and its
  37  * contributors.
  38  */
  39
  40 #pragma ident   "%Z%%M% %I%     %E% SMI"
  41
  42 #include        <ctype.h>
  43 #include        "tdef.h"
  44 #include "ext.h"
  45 #define HY_BIT  0200    /* stuff in here only works for ascii */
  46
  47 /*
  48  * troff8.c
  49  *
  50  * hyphenation
  51  */
  52
  53 char    hbuf[NHEX];
  54 char    *nexth = hbuf;
  55 tchar   *hyend;
  56 #define THRESH 160 /*digram goodness threshold*/
  57 int     thresh = THRESH;
  58
  59 int
  60 hyphen(wp)
  61         tchar *wp;
  62 {
  63         int     j;
  64         tchar *i;
  65
  66         i = wp;
  67         while (punct(cbits(*i++)))
  68                 ;
  69         if (!alph(cbits(*--i)))
  70                 return (0);
  71         wdstart = i++;
  72         while (alph(cbits(*i++)))
  73                 ;
  74         hyend = wdend = --i - 1;
  75         while (punct(cbits(*i++)))
  76                 ;
  77         if (*--i)
  78                 return (0);
  79         if ((wdend - wdstart - 4) < 0)
  80                 return (0);
  81         hyp = hyptr;
  82         *hyp = 0;
  83         hyoff = 2;
  84         if (!exword() && !suffix())
  85                 digram();
  86         *hyp++ = 0;
  87         if (*hyptr)
  88                 for (j = 1; j; ) {
  89                         j = 0;
  90                         for (hyp = hyptr + 1; *hyp != 0; hyp++) {
  91                                 if (*(hyp - 1) > *hyp) {
  92                                         j++;
  93                                         i = *hyp;
  94                                         *hyp = *(hyp - 1);
  95                                         *(hyp - 1) = i;
  96                                 }
  97                         }
  98                 }
  99
 100         return (0);
 101 }
 102
 103
 104 int
 105 punct(i)
 106 {
 107         if (!i || alph(i))
 108                 return(0);
 109         else
 110                 return(1);
 111 }
 112
 113
 114 int
 115 alph(i)
 116 {
 117         if (i >= 'a' && i <= 'z' || i >= 'A' && i <= 'Z')
 118                 return(1);
 119         else
 120                 return(0);
 121 }
 122
 123
 124 int
 125 caseht()
 126 {
 127         thresh = THRESH;
 128         if (skip())
 129                 return (0);
 130         noscale++;
 131         thresh = atoi();
 132         noscale = 0;
 133
 134         return (0);
 135 }
 136
 137
 138 int
 139 casehw()
 140 {
 141         int     i, k;
 142         char    *j;
 143         tchar t;
 144
 145         k = 0;
 146         while (!skip()) {
 147                 if ((j = nexth) >= (hbuf + NHEX - 2))
 148                         goto full;
 149                 for (; ; ) {
 150                         if (ismot(t = getch()))
 151                                 continue;
 152                         i = cbits(t);
 153                         if (i == ' ' || i == '\n') {
 154                                 *j++ = 0;
 155                                 nexth = j;
 156                                 *j = 0;
 157                                 if (i == ' ')
 158                                         break;
 159                                 else
 160                                         return (0);
 161                         }
 162                         if (i == '-') {
 163                                 k = HY_BIT;
 164                                 continue;
 165                         }
 166                         *j++ = maplow(i) | k;
 167                         k = 0;
 168                         if (j >= (hbuf + NHEX - 2))
 169                                 goto full;
 170                 }
 171         }
 172         return (0);
 173 full:
 174         errprint(gettext("exception word list full."));
 175         *nexth = 0;
 176
 177         return (0);
 178 }
 179
 180
 181 int
 182 exword()
 183 {
 184         tchar *w;
 185         char    *e;
 186         char    *save;
 187
 188         e = hbuf;
 189         while (1) {
 190                 save = e;
 191                 if (*e == 0)
 192                         return(0);
 193                 w = wdstart;
 194                 while (*e && w <= hyend && (*e & 0177) == maplow(cbits(*w))) {
 195                         e++;
 196                         w++;
 197                 };
 198                 if (!*e) {
 199                         if (w-1 == hyend || (w == wdend && maplow(cbits(*w)) == 's')) {
 200                                 w = wdstart;
 201                                 for (e = save; *e; e++) {
 202                                         if (*e & HY_BIT)
 203                                                 *hyp++ = w;
 204                                         if (hyp > (hyptr + NHYP - 1))
 205                                                 hyp = hyptr + NHYP - 1;
 206                                         w++;
 207                                 }
 208                                 return(1);
 209                         } else {
 210                                 e++;
 211                                 continue;
 212                         }
 213                 } else
 214                         while (*e++)
 215                                 ;
 216         }
 217
 218         return (0);
 219 }
 220
 221
 222 int
 223 suffix()
 224 {
 225         tchar *w;
 226         char    *s, *s0;
 227         tchar i;
 228         extern char     *suftab[];
 229         extern tchar *chkvow();
 230
 231 again:
 232         if (!alph(cbits(i = cbits(*hyend))))
 233                 return(0);
 234         if (i < 'a')
 235                 i -= 'A' - 'a';
 236         if ((s0 = suftab[i-'a']) == 0)
 237                 return(0);
 238         for (; ; ) {
 239                 if ((i = *s0 & 017) == 0)
 240                         return(0);
 241                 s = s0 + i - 1;
 242                 w = hyend - 1;
 243                 while (s > s0 && w >= wdstart && (*s & 0177) == maplow(cbits(*w))) {
 244                         s--;
 245                         w--;
 246                 }
 247                 if (s == s0)
 248                         break;
 249                 s0 += i;
 250         }
 251         s = s0 + i - 1;
 252         w = hyend;
 253         if (*s0 & HY_BIT)
 254                 goto mark;
 255         while (s > s0) {
 256                 w--;
 257                 if (*s-- & HY_BIT) {
 258 mark:
 259                         hyend = w - 1;
 260                         if (*s0 & 0100)
 261                                 continue;
 262                         if (!chkvow(w))
 263                                 return(0);
 264                         *hyp++ = w;
 265                 }
 266         }
 267         if (*s0 & 040)
 268                 return(0);
 269         if (exword())
 270                 return(1);
 271         goto again;
 272 }
 273
 274
 275 int
 276 maplow(i)
 277 int     i;
 278 {
 279         if (ischar(i) && isupper(i))
 280                 i = tolower(i);
 281         return(i);
 282 }
 283
 284
 285 int
 286 vowel(i)
 287 int     i;
 288 {
 289         switch (maplow(i)) {
 290         case 'a':
 291         case 'e':
 292         case 'i':
 293         case 'o':
 294         case 'u':
 295         case 'y':
 296                 return(1);
 297         default:
 298                 return(0);
 299         }
 300 }
 301
 302
 303 tchar *chkvow(w)
 304 tchar *w;
 305 {
 306         while (--w >= wdstart)
 307                 if (vowel(cbits(*w)))
 308                         return(w);
 309         return(0);
 310 }
 311
 312
 313 int
 314 digram()
 315 {
 316         tchar *w;
 317         int     val;
 318         tchar * nhyend, *maxw;
 319         int     maxval;
 320         extern char     bxh[26][13], bxxh[26][13], xxh[26][13], xhx[26][13], hxx[26][13];
 321
 322 again:
 323         if (!(w = chkvow(hyend + 1)))
 324                 return (0);
 325         hyend = w;
 326         if (!(w = chkvow(hyend)))
 327                 return (0);
 328         nhyend = w;
 329         maxval = 0;
 330         w--;
 331         while ((++w < hyend) && (w < (wdend - 1))) {
 332                 val = 1;
 333                 if (w == wdstart)
 334                         val *= dilook('a', cbits(*w), bxh);
 335                 else if (w == wdstart + 1)
 336                         val *= dilook(cbits(*(w-1)), cbits(*w), bxxh);
 337                 else
 338                         val *= dilook(cbits(*(w-1)), cbits(*w), xxh);
 339                 val *= dilook(cbits(*w), cbits(*(w+1)), xhx);
 340                 val *= dilook(cbits(*(w+1)), cbits(*(w+2)), hxx);
 341                 if (val > maxval) {
 342                         maxval = val;
 343                         maxw = w + 1;
 344                 }
 345         }
 346         hyend = nhyend;
 347         if (maxval > thresh)
 348                 *hyp++ = maxw;
 349         goto again;
 350 }
 351
 352
 353 int
 354 dilook(a, b, t)
 355 int     a, b;
 356 char    t[26][13];
 357 {
 358         int     i, j;
 359
 360         i = t[maplow(a)-'a'][(j = maplow(b)-'a')/2];
 361         if (!(j & 01))
 362                 i >>= 4;
 363         return(i & 017);
 364 }
 365
 366