mandoc.c

   1 /*      $Id: mandoc.c,v 1.110 2018/12/14 06:33:14 schwarze Exp $ */
   2 /*
   3  * Copyright (c) 2008-2011, 2014 Kristaps Dzonsons <kristaps@bsd.lv>
   4  * Copyright (c) 2011-2015, 2017, 2018 Ingo Schwarze <schwarze@openbsd.org>
   5  *
   6  * Permission to use, copy, modify, and distribute this software for any
   7  * purpose with or without fee is hereby granted, provided that the above
   8  * copyright notice and this permission notice appear in all copies.
   9  *
  10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHORS DISCLAIM ALL WARRANTIES
  11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR
  13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  17  */
  18 #include "config.h"
  19
  20 #include <sys/types.h>
  21
  22 #include <assert.h>
  23 #include <ctype.h>
  24 #include <errno.h>
  25 #include <limits.h>
  26 #include <stdlib.h>
  27 #include <stdio.h>
  28 #include <string.h>
  29 #include <time.h>
  30
  31 #include "mandoc_aux.h"
  32 #include "mandoc.h"
  33 #include "roff.h"
  34 #include "libmandoc.h"
  35
  36 static  int      a2time(time_t *, const char *, const char *);
  37 static  char    *time2a(time_t);
  38
  39
  40 enum mandoc_esc
  41 mandoc_escape(const char **end, const char **start, int *sz)
  42 {
  43         const char      *local_start;
  44         int              local_sz, c, i;
  45         char             term;
  46         enum mandoc_esc  gly;
  47
  48         /*
  49          * When the caller doesn't provide return storage,
  50          * use local storage.
  51          */
  52
  53         if (NULL == start)
  54                 start = &local_start;
  55         if (NULL == sz)
  56                 sz = &local_sz;
  57
  58         /*
  59          * Beyond the backslash, at least one input character
  60          * is part of the escape sequence.  With one exception
  61          * (see below), that character won't be returned.
  62          */
  63
  64         gly = ESCAPE_ERROR;
  65         *start = ++*end;
  66         *sz = 0;
  67         term = '\0';
  68
  69         switch ((*start)[-1]) {
  70         /*
  71          * First the glyphs.  There are several different forms of
  72          * these, but each eventually returns a substring of the glyph
  73          * name.
  74          */
  75         case '(':
  76                 gly = ESCAPE_SPECIAL;
  77                 *sz = 2;
  78                 break;
  79         case '[':
  80                 gly = ESCAPE_SPECIAL;
  81                 term = ']';
  82                 break;
  83         case 'C':
  84                 if ('\'' != **start)
  85                         return ESCAPE_ERROR;
  86                 *start = ++*end;
  87                 gly = ESCAPE_SPECIAL;
  88                 term = '\'';
  89                 break;
  90
  91         /*
  92          * Escapes taking no arguments at all.
  93          */
  94         case 'd':
  95         case 'u':
  96         case ',':
  97         case '/':
  98                 return ESCAPE_IGNORE;
  99         case 'p':
 100                 return ESCAPE_BREAK;
 101
 102         /*
 103          * The \z escape is supposed to output the following
 104          * character without advancing the cursor position.
 105          * Since we are mostly dealing with terminal mode,
 106          * let us just skip the next character.
 107          */
 108         case 'z':
 109                 return ESCAPE_SKIPCHAR;
 110
 111         /*
 112          * Handle all triggers matching \X(xy, \Xx, and \X[xxxx], where
 113          * 'X' is the trigger.  These have opaque sub-strings.
 114          */
 115         case 'F':
 116         case 'g':
 117         case 'k':
 118         case 'M':
 119         case 'm':
 120         case 'n':
 121         case 'V':
 122         case 'Y':
 123                 gly = ESCAPE_IGNORE;
 124                 /* FALLTHROUGH */
 125         case 'f':
 126                 if (ESCAPE_ERROR == gly)
 127                         gly = ESCAPE_FONT;
 128                 switch (**start) {
 129                 case '(':
 130                         *start = ++*end;
 131                         *sz = 2;
 132                         break;
 133                 case '[':
 134                         *start = ++*end;
 135                         term = ']';
 136                         break;
 137                 default:
 138                         *sz = 1;
 139                         break;
 140                 }
 141                 break;
 142         case '*':
 143                 if (strncmp(*start, "(.T", 3) != 0)
 144                         abort();
 145                 gly = ESCAPE_DEVICE;
 146                 *start = ++*end;
 147                 *sz = 2;
 148                 break;
 149
 150         /*
 151          * These escapes are of the form \X'Y', where 'X' is the trigger
 152          * and 'Y' is any string.  These have opaque sub-strings.
 153          * The \B and \w escapes are handled in roff.c, roff_res().
 154          */
 155         case 'A':
 156         case 'b':
 157         case 'D':
 158         case 'R':
 159         case 'X':
 160         case 'Z':
 161                 gly = ESCAPE_IGNORE;
 162                 /* FALLTHROUGH */
 163         case 'o':
 164                 if (**start == '\0')
 165                         return ESCAPE_ERROR;
 166                 if (gly == ESCAPE_ERROR)
 167                         gly = ESCAPE_OVERSTRIKE;
 168                 term = **start;
 169                 *start = ++*end;
 170                 break;
 171
 172         /*
 173          * These escapes are of the form \X'N', where 'X' is the trigger
 174          * and 'N' resolves to a numerical expression.
 175          */
 176         case 'h':
 177         case 'H':
 178         case 'L':
 179         case 'l':
 180         case 'S':
 181         case 'v':
 182         case 'x':
 183                 if (strchr(" %&()*+-./0123456789:<=>", **start)) {
 184                         if ('\0' != **start)
 185                                 ++*end;
 186                         return ESCAPE_ERROR;
 187                 }
 188                 switch ((*start)[-1]) {
 189                 case 'h':
 190                         gly = ESCAPE_HORIZ;
 191                         break;
 192                 case 'l':
 193                         gly = ESCAPE_HLINE;
 194                         break;
 195                 default:
 196                         gly = ESCAPE_IGNORE;
 197                         break;
 198                 }
 199                 term = **start;
 200                 *start = ++*end;
 201                 break;
 202
 203         /*
 204          * Special handling for the numbered character escape.
 205          * XXX Do any other escapes need similar handling?
 206          */
 207         case 'N':
 208                 if ('\0' == **start)
 209                         return ESCAPE_ERROR;
 210                 (*end)++;
 211                 if (isdigit((unsigned char)**start)) {
 212                         *sz = 1;
 213                         return ESCAPE_IGNORE;
 214                 }
 215                 (*start)++;
 216                 while (isdigit((unsigned char)**end))
 217                         (*end)++;
 218                 *sz = *end - *start;
 219                 if ('\0' != **end)
 220                         (*end)++;
 221                 return ESCAPE_NUMBERED;
 222
 223         /*
 224          * Sizes get a special category of their own.
 225          */
 226         case 's':
 227                 gly = ESCAPE_IGNORE;
 228
 229                 /* See +/- counts as a sign. */
 230                 if ('+' == **end || '-' == **end || ASCII_HYPH == **end)
 231                         *start = ++*end;
 232
 233                 switch (**end) {
 234                 case '(':
 235                         *start = ++*end;
 236                         *sz = 2;
 237                         break;
 238                 case '[':
 239                         *start = ++*end;
 240                         term = ']';
 241                         break;
 242                 case '\'':
 243                         *start = ++*end;
 244                         term = '\'';
 245                         break;
 246                 case '3':
 247                 case '2':
 248                 case '1':
 249                         *sz = (*end)[-1] == 's' &&
 250                             isdigit((unsigned char)(*end)[1]) ? 2 : 1;
 251                         break;
 252                 default:
 253                         *sz = 1;
 254                         break;
 255                 }
 256
 257                 break;
 258
 259         /*
 260          * Anything else is assumed to be a glyph.
 261          * In this case, pass back the character after the backslash.
 262          */
 263         default:
 264                 gly = ESCAPE_SPECIAL;
 265                 *start = --*end;
 266                 *sz = 1;
 267                 break;
 268         }
 269
 270         assert(ESCAPE_ERROR != gly);
 271
 272         /*
 273          * Read up to the terminating character,
 274          * paying attention to nested escapes.
 275          */
 276
 277         if ('\0' != term) {
 278                 while (**end != term) {
 279                         switch (**end) {
 280                         case '\0':
 281                                 return ESCAPE_ERROR;
 282                         case '\\':
 283                                 (*end)++;
 284                                 if (ESCAPE_ERROR ==
 285                                     mandoc_escape(end, NULL, NULL))
 286                                         return ESCAPE_ERROR;
 287                                 break;
 288                         default:
 289                                 (*end)++;
 290                                 break;
 291                         }
 292                 }
 293                 *sz = (*end)++ - *start;
 294         } else {
 295                 assert(*sz > 0);
 296                 if ((size_t)*sz > strlen(*start))
 297                         return ESCAPE_ERROR;
 298                 *end += *sz;
 299         }
 300
 301         /* Run post-processors. */
 302
 303         switch (gly) {
 304         case ESCAPE_FONT:
 305                 if (*sz == 2) {
 306                         if (**start == 'C') {
 307                                 if ((*start)[1] == 'W' ||
 308                                     (*start)[1] == 'R') {
 309                                         gly = ESCAPE_FONTCW;
 310                                         break;
 311                                 }
 312                                 /*
 313                                  * Treat other constant-width font modes
 314                                  * just like regular font modes.
 315                                  */
 316                                 (*start)++;
 317                                 (*sz)--;
 318                         } else {
 319                                 if ((*start)[0] == 'B' && (*start)[1] == 'I')
 320                                         gly = ESCAPE_FONTBI;
 321                                 break;
 322                         }
 323                 } else if (*sz != 1) {
 324                         if (*sz == 0)
 325                                 gly = ESCAPE_FONTPREV;
 326                         break;
 327                 }
 328
 329                 switch (**start) {
 330                 case '3':
 331                 case 'B':
 332                         gly = ESCAPE_FONTBOLD;
 333                         break;
 334                 case '2':
 335                 case 'I':
 336                         gly = ESCAPE_FONTITALIC;
 337                         break;
 338                 case 'P':
 339                         gly = ESCAPE_FONTPREV;
 340                         break;
 341                 case '1':
 342                 case 'R':
 343                         gly = ESCAPE_FONTROMAN;
 344                         break;
 345                 }
 346                 break;
 347         case ESCAPE_SPECIAL:
 348                 if (**start == 'c') {
 349                         if (*sz == 1) {
 350                                 gly = ESCAPE_NOSPACE;
 351                                 break;
 352                         }
 353                         if (*sz < 6 || *sz > 7 ||
 354                             strncmp(*start, "char", 4) != 0 ||
 355                             (int)strspn(*start + 4, "0123456789") + 4 < *sz)
 356                                 break;
 357                         c = 0;
 358                         for (i = 4; i < *sz; i++)
 359                                 c = 10 * c + ((*start)[i] - '0');
 360                         if (c < 0x21 || (c > 0x7e && c < 0xa0) || c > 0xff)
 361                                 break;
 362                         *start += 4;
 363                         *sz -= 4;
 364                         gly = ESCAPE_NUMBERED;
 365                         break;
 366                 }
 367
 368                 /*
 369                  * Unicode escapes are defined in groff as \[u0000]
 370                  * to \[u10FFFF], where the contained value must be
 371                  * a valid Unicode codepoint.  Here, however, only
 372                  * check the length and range.
 373                  */
 374                 if (**start != 'u' || *sz < 5 || *sz > 7)
 375                         break;
 376                 if (*sz == 7 && ((*start)[1] != '1' || (*start)[2] != '0'))
 377                         break;
 378                 if (*sz == 6 && (*start)[1] == '0')
 379                         break;
 380                 if (*sz == 5 && (*start)[1] == 'D' &&
 381                     strchr("89ABCDEF", (*start)[2]) != NULL)
 382                         break;
 383                 if ((int)strspn(*start + 1, "0123456789ABCDEFabcdef")
 384                     + 1 == *sz)
 385                         gly = ESCAPE_UNICODE;
 386                 break;
 387         default:
 388                 break;
 389         }
 390
 391         return gly;
 392 }
 393
 394 /*
 395  * Parse a quoted or unquoted roff-style request or macro argument.
 396  * Return a pointer to the parsed argument, which is either the original
 397  * pointer or advanced by one byte in case the argument is quoted.
 398  * NUL-terminate the argument in place.
 399  * Collapse pairs of quotes inside quoted arguments.
 400  * Advance the argument pointer to the next argument,
 401  * or to the NUL byte terminating the argument line.
 402  */
 403 char *
 404 mandoc_getarg(char **cpp, int ln, int *pos)
 405 {
 406         char     *start, *cp;
 407         int       quoted, pairs, white;
 408
 409         /* Quoting can only start with a new word. */
 410         start = *cpp;
 411         quoted = 0;
 412         if ('"' == *start) {
 413                 quoted = 1;
 414                 start++;
 415         }
 416
 417         pairs = 0;
 418         white = 0;
 419         for (cp = start; '\0' != *cp; cp++) {
 420
 421                 /*
 422                  * Move the following text left
 423                  * after quoted quotes and after "\\" and "\t".
 424                  */
 425                 if (pairs)
 426                         cp[-pairs] = cp[0];
 427
 428                 if ('\\' == cp[0]) {
 429                         /*
 430                          * In copy mode, translate double to single
 431                          * backslashes and backslash-t to literal tabs.
 432                          */
 433                         switch (cp[1]) {
 434                         case 't':
 435                                 cp[0] = '\t';
 436                                 /* FALLTHROUGH */
 437                         case '\\':
 438                                 pairs++;
 439                                 cp++;
 440                                 break;
 441                         case ' ':
 442                                 /* Skip escaped blanks. */
 443                                 if (0 == quoted)
 444                                         cp++;
 445                                 break;
 446                         default:
 447                                 break;
 448                         }
 449                 } else if (0 == quoted) {
 450                         if (' ' == cp[0]) {
 451                                 /* Unescaped blanks end unquoted args. */
 452                                 white = 1;
 453                                 break;
 454                         }
 455                 } else if ('"' == cp[0]) {
 456                         if ('"' == cp[1]) {
 457                                 /* Quoted quotes collapse. */
 458                                 pairs++;
 459                                 cp++;
 460                         } else {
 461                                 /* Unquoted quotes end quoted args. */
 462                                 quoted = 2;
 463                                 break;
 464                         }
 465                 }
 466         }
 467
 468         /* Quoted argument without a closing quote. */
 469         if (1 == quoted)
 470                 mandoc_msg(MANDOCERR_ARG_QUOTE, ln, *pos, NULL);
 471
 472         /* NUL-terminate this argument and move to the next one. */
 473         if (pairs)
 474                 cp[-pairs] = '\0';
 475         if ('\0' != *cp) {
 476                 *cp++ = '\0';
 477                 while (' ' == *cp)
 478                         cp++;
 479         }
 480         *pos += (int)(cp - start) + (quoted ? 1 : 0);
 481         *cpp = cp;
 482
 483         if ('\0' == *cp && (white || ' ' == cp[-1]))
 484                 mandoc_msg(MANDOCERR_SPACE_EOL, ln, *pos, NULL);
 485
 486         return start;
 487 }
 488
 489 static int
 490 a2time(time_t *t, const char *fmt, const char *p)
 491 {
 492         struct tm        tm;
 493         char            *pp;
 494
 495         memset(&tm, 0, sizeof(struct tm));
 496
 497         pp = NULL;
 498 #if HAVE_STRPTIME
 499         pp = strptime(p, fmt, &tm);
 500 #endif
 501         if (NULL != pp && '\0' == *pp) {
 502                 *t = mktime(&tm);
 503                 return 1;
 504         }
 505
 506         return 0;
 507 }
 508
 509 static char *
 510 time2a(time_t t)
 511 {
 512         struct tm       *tm;
 513         char            *buf, *p;
 514         size_t           ssz;
 515         int              isz;
 516
 517         tm = localtime(&t);
 518         if (tm == NULL)
 519                 return NULL;
 520
 521         /*
 522          * Reserve space:
 523          * up to 9 characters for the month (September) + blank
 524          * up to 2 characters for the day + comma + blank
 525          * 4 characters for the year and a terminating '\0'
 526          */
 527
 528         p = buf = mandoc_malloc(10 + 4 + 4 + 1);
 529
 530         if ((ssz = strftime(p, 10 + 1, "%B ", tm)) == 0)
 531                 goto fail;
 532         p += (int)ssz;
 533
 534         /*
 535          * The output format is just "%d" here, not "%2d" or "%02d".
 536          * That's also the reason why we can't just format the
 537          * date as a whole with "%B %e, %Y" or "%B %d, %Y".
 538          * Besides, the present approach is less prone to buffer
 539          * overflows, in case anybody should ever introduce the bug
 540          * of looking at LC_TIME.
 541          */
 542
 543         if ((isz = snprintf(p, 4 + 1, "%d, ", tm->tm_mday)) == -1)
 544                 goto fail;
 545         p += isz;
 546
 547         if (strftime(p, 4 + 1, "%Y", tm) == 0)
 548                 goto fail;
 549         return buf;
 550
 551 fail:
 552         free(buf);
 553         return NULL;
 554 }
 555
 556 char *
 557 mandoc_normdate(struct roff_man *man, char *in, int ln, int pos)
 558 {
 559         char            *cp;
 560         time_t           t;
 561
 562         /* No date specified: use today's date. */
 563
 564         if (in == NULL || *in == '\0' || strcmp(in, "$" "Mdocdate$") == 0) {
 565                 mandoc_msg(MANDOCERR_DATE_MISSING, ln, pos, NULL);
 566                 return time2a(time(NULL));
 567         }
 568
 569         /* Valid mdoc(7) date format. */
 570
 571         if (a2time(&t, "$" "Mdocdate: %b %d %Y $", in) ||
 572             a2time(&t, "%b %d, %Y", in)) {
 573                 cp = time2a(t);
 574                 if (t > time(NULL) + 86400)
 575                         mandoc_msg(MANDOCERR_DATE_FUTURE, ln, pos, "%s", cp);
 576                 else if (*in != '$' && strcmp(in, cp) != 0)
 577                         mandoc_msg(MANDOCERR_DATE_NORM, ln, pos, "%s", cp);
 578                 return cp;
 579         }
 580
 581         /* In man(7), do not warn about the legacy format. */
 582
 583         if (a2time(&t, "%Y-%m-%d", in) == 0)
 584                 mandoc_msg(MANDOCERR_DATE_BAD, ln, pos, "%s", in);
 585         else if (t > time(NULL) + 86400)
 586                 mandoc_msg(MANDOCERR_DATE_FUTURE, ln, pos, "%s", in);
 587         else if (man->macroset == MACROSET_MDOC)
 588                 mandoc_msg(MANDOCERR_DATE_LEGACY, ln, pos, "Dd %s", in);
 589
 590         /* Use any non-mdoc(7) date verbatim. */
 591
 592         return mandoc_strdup(in);
 593 }
 594
 595 int
 596 mandoc_eos(const char *p, size_t sz)
 597 {
 598         const char      *q;
 599         int              enclosed, found;
 600
 601         if (0 == sz)
 602                 return 0;
 603
 604         /*
 605          * End-of-sentence recognition must include situations where
 606          * some symbols, such as `)', allow prior EOS punctuation to
 607          * propagate outward.
 608          */
 609
 610         enclosed = found = 0;
 611         for (q = p + (int)sz - 1; q >= p; q--) {
 612                 switch (*q) {
 613                 case '\"':
 614                 case '\'':
 615                 case ']':
 616                 case ')':
 617                         if (0 == found)
 618                                 enclosed = 1;
 619                         break;
 620                 case '.':
 621                 case '!':
 622                 case '?':
 623                         found = 1;
 624                         break;
 625                 default:
 626                         return found &&
 627                             (!enclosed || isalnum((unsigned char)*q));
 628                 }
 629         }
 630
 631         return found && !enclosed;
 632 }
 633
 634 /*
 635  * Convert a string to a long that may not be <0.
 636  * If the string is invalid, or is less than 0, return -1.
 637  */
 638 int
 639 mandoc_strntoi(const char *p, size_t sz, int base)
 640 {
 641         char             buf[32];
 642         char            *ep;
 643         long             v;
 644
 645         if (sz > 31)
 646                 return -1;
 647
 648         memcpy(buf, p, sz);
 649         buf[(int)sz] = '\0';
 650
 651         errno = 0;
 652         v = strtol(buf, &ep, base);
 653
 654         if (buf[0] == '\0' || *ep != '\0')
 655                 return -1;
 656
 657         if (v > INT_MAX)
 658                 v = INT_MAX;
 659         if (v < INT_MIN)
 660                 v = INT_MIN;
 661
 662         return (int)v;
 663 }