mandoc.c

   1 /*      $Id: mandoc.c,v 1.107 2018/08/20 18:06:56 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                                 /*
 308                                  * Treat constant-width font modes
 309                                  * just like regular font modes.
 310                                  */
 311                                 (*start)++;
 312                                 (*sz)--;
 313                         } else {
 314                                 if ((*start)[0] == 'B' && (*start)[1] == 'I')
 315                                         gly = ESCAPE_FONTBI;
 316                                 break;
 317                         }
 318                 } else if (*sz != 1) {
 319                         if (*sz == 0)
 320                                 gly = ESCAPE_FONTPREV;
 321                         break;
 322                 }
 323
 324                 switch (**start) {
 325                 case '3':
 326                 case 'B':
 327                         gly = ESCAPE_FONTBOLD;
 328                         break;
 329                 case '2':
 330                 case 'I':
 331                         gly = ESCAPE_FONTITALIC;
 332                         break;
 333                 case 'P':
 334                         gly = ESCAPE_FONTPREV;
 335                         break;
 336                 case '1':
 337                 case 'R':
 338                         gly = ESCAPE_FONTROMAN;
 339                         break;
 340                 }
 341                 break;
 342         case ESCAPE_SPECIAL:
 343                 if (**start == 'c') {
 344                         if (*sz == 1) {
 345                                 gly = ESCAPE_NOSPACE;
 346                                 break;
 347                         }
 348                         if (*sz < 6 || *sz > 7 ||
 349                             strncmp(*start, "char", 4) != 0 ||
 350                             (int)strspn(*start + 4, "0123456789") + 4 < *sz)
 351                                 break;
 352                         c = 0;
 353                         for (i = 4; i < *sz; i++)
 354                                 c = 10 * c + ((*start)[i] - '0');
 355                         if (c < 0x21 || (c > 0x7e && c < 0xa0) || c > 0xff)
 356                                 break;
 357                         *start += 4;
 358                         *sz -= 4;
 359                         gly = ESCAPE_NUMBERED;
 360                         break;
 361                 }
 362
 363                 /*
 364                  * Unicode escapes are defined in groff as \[u0000]
 365                  * to \[u10FFFF], where the contained value must be
 366                  * a valid Unicode codepoint.  Here, however, only
 367                  * check the length and range.
 368                  */
 369                 if (**start != 'u' || *sz < 5 || *sz > 7)
 370                         break;
 371                 if (*sz == 7 && ((*start)[1] != '1' || (*start)[2] != '0'))
 372                         break;
 373                 if (*sz == 6 && (*start)[1] == '0')
 374                         break;
 375                 if (*sz == 5 && (*start)[1] == 'D' &&
 376                     strchr("89ABCDEF", (*start)[2]) != NULL)
 377                         break;
 378                 if ((int)strspn(*start + 1, "0123456789ABCDEFabcdef")
 379                     + 1 == *sz)
 380                         gly = ESCAPE_UNICODE;
 381                 break;
 382         default:
 383                 break;
 384         }
 385
 386         return gly;
 387 }
 388
 389 /*
 390  * Parse a quoted or unquoted roff-style request or macro argument.
 391  * Return a pointer to the parsed argument, which is either the original
 392  * pointer or advanced by one byte in case the argument is quoted.
 393  * NUL-terminate the argument in place.
 394  * Collapse pairs of quotes inside quoted arguments.
 395  * Advance the argument pointer to the next argument,
 396  * or to the NUL byte terminating the argument line.
 397  */
 398 char *
 399 mandoc_getarg(struct mparse *parse, char **cpp, int ln, int *pos)
 400 {
 401         char     *start, *cp;
 402         int       quoted, pairs, white;
 403
 404         /* Quoting can only start with a new word. */
 405         start = *cpp;
 406         quoted = 0;
 407         if ('"' == *start) {
 408                 quoted = 1;
 409                 start++;
 410         }
 411
 412         pairs = 0;
 413         white = 0;
 414         for (cp = start; '\0' != *cp; cp++) {
 415
 416                 /*
 417                  * Move the following text left
 418                  * after quoted quotes and after "\\" and "\t".
 419                  */
 420                 if (pairs)
 421                         cp[-pairs] = cp[0];
 422
 423                 if ('\\' == cp[0]) {
 424                         /*
 425                          * In copy mode, translate double to single
 426                          * backslashes and backslash-t to literal tabs.
 427                          */
 428                         switch (cp[1]) {
 429                         case 't':
 430                                 cp[0] = '\t';
 431                                 /* FALLTHROUGH */
 432                         case '\\':
 433                                 pairs++;
 434                                 cp++;
 435                                 break;
 436                         case ' ':
 437                                 /* Skip escaped blanks. */
 438                                 if (0 == quoted)
 439                                         cp++;
 440                                 break;
 441                         default:
 442                                 break;
 443                         }
 444                 } else if (0 == quoted) {
 445                         if (' ' == cp[0]) {
 446                                 /* Unescaped blanks end unquoted args. */
 447                                 white = 1;
 448                                 break;
 449                         }
 450                 } else if ('"' == cp[0]) {
 451                         if ('"' == cp[1]) {
 452                                 /* Quoted quotes collapse. */
 453                                 pairs++;
 454                                 cp++;
 455                         } else {
 456                                 /* Unquoted quotes end quoted args. */
 457                                 quoted = 2;
 458                                 break;
 459                         }
 460                 }
 461         }
 462
 463         /* Quoted argument without a closing quote. */
 464         if (1 == quoted)
 465                 mandoc_msg(MANDOCERR_ARG_QUOTE, parse, ln, *pos, NULL);
 466
 467         /* NUL-terminate this argument and move to the next one. */
 468         if (pairs)
 469                 cp[-pairs] = '\0';
 470         if ('\0' != *cp) {
 471                 *cp++ = '\0';
 472                 while (' ' == *cp)
 473                         cp++;
 474         }
 475         *pos += (int)(cp - start) + (quoted ? 1 : 0);
 476         *cpp = cp;
 477
 478         if ('\0' == *cp && (white || ' ' == cp[-1]))
 479                 mandoc_msg(MANDOCERR_SPACE_EOL, parse, ln, *pos, NULL);
 480
 481         return start;
 482 }
 483
 484 static int
 485 a2time(time_t *t, const char *fmt, const char *p)
 486 {
 487         struct tm        tm;
 488         char            *pp;
 489
 490         memset(&tm, 0, sizeof(struct tm));
 491
 492         pp = NULL;
 493 #if HAVE_STRPTIME
 494         pp = strptime(p, fmt, &tm);
 495 #endif
 496         if (NULL != pp && '\0' == *pp) {
 497                 *t = mktime(&tm);
 498                 return 1;
 499         }
 500
 501         return 0;
 502 }
 503
 504 static char *
 505 time2a(time_t t)
 506 {
 507         struct tm       *tm;
 508         char            *buf, *p;
 509         size_t           ssz;
 510         int              isz;
 511
 512         tm = localtime(&t);
 513         if (tm == NULL)
 514                 return NULL;
 515
 516         /*
 517          * Reserve space:
 518          * up to 9 characters for the month (September) + blank
 519          * up to 2 characters for the day + comma + blank
 520          * 4 characters for the year and a terminating '\0'
 521          */
 522
 523         p = buf = mandoc_malloc(10 + 4 + 4 + 1);
 524
 525         if ((ssz = strftime(p, 10 + 1, "%B ", tm)) == 0)
 526                 goto fail;
 527         p += (int)ssz;
 528
 529         /*
 530          * The output format is just "%d" here, not "%2d" or "%02d".
 531          * That's also the reason why we can't just format the
 532          * date as a whole with "%B %e, %Y" or "%B %d, %Y".
 533          * Besides, the present approach is less prone to buffer
 534          * overflows, in case anybody should ever introduce the bug
 535          * of looking at LC_TIME.
 536          */
 537
 538         if ((isz = snprintf(p, 4 + 1, "%d, ", tm->tm_mday)) == -1)
 539                 goto fail;
 540         p += isz;
 541
 542         if (strftime(p, 4 + 1, "%Y", tm) == 0)
 543                 goto fail;
 544         return buf;
 545
 546 fail:
 547         free(buf);
 548         return NULL;
 549 }
 550
 551 char *
 552 mandoc_normdate(struct roff_man *man, char *in, int ln, int pos)
 553 {
 554         char            *cp;
 555         time_t           t;
 556
 557         /* No date specified: use today's date. */
 558
 559         if (in == NULL || *in == '\0' || strcmp(in, "$" "Mdocdate$") == 0) {
 560                 mandoc_msg(MANDOCERR_DATE_MISSING, man->parse, ln, pos, NULL);
 561                 return time2a(time(NULL));
 562         }
 563
 564         /* Valid mdoc(7) date format. */
 565
 566         if (a2time(&t, "$" "Mdocdate: %b %d %Y $", in) ||
 567             a2time(&t, "%b %d, %Y", in)) {
 568                 cp = time2a(t);
 569                 if (t > time(NULL) + 86400)
 570                         mandoc_msg(MANDOCERR_DATE_FUTURE, man->parse,
 571                             ln, pos, cp);
 572                 else if (*in != '$' && strcmp(in, cp) != 0)
 573                         mandoc_msg(MANDOCERR_DATE_NORM, man->parse,
 574                             ln, pos, cp);
 575                 return cp;
 576         }
 577
 578         /* In man(7), do not warn about the legacy format. */
 579
 580         if (a2time(&t, "%Y-%m-%d", in) == 0)
 581                 mandoc_msg(MANDOCERR_DATE_BAD, man->parse, ln, pos, in);
 582         else if (t > time(NULL) + 86400)
 583                 mandoc_msg(MANDOCERR_DATE_FUTURE, man->parse, ln, pos, in);
 584         else if (man->macroset == MACROSET_MDOC)
 585                 mandoc_vmsg(MANDOCERR_DATE_LEGACY, man->parse,
 586                     ln, pos, "Dd %s", in);
 587
 588         /* Use any non-mdoc(7) date verbatim. */
 589
 590         return mandoc_strdup(in);
 591 }
 592
 593 int
 594 mandoc_eos(const char *p, size_t sz)
 595 {
 596         const char      *q;
 597         int              enclosed, found;
 598
 599         if (0 == sz)
 600                 return 0;
 601
 602         /*
 603          * End-of-sentence recognition must include situations where
 604          * some symbols, such as `)', allow prior EOS punctuation to
 605          * propagate outward.
 606          */
 607
 608         enclosed = found = 0;
 609         for (q = p + (int)sz - 1; q >= p; q--) {
 610                 switch (*q) {
 611                 case '\"':
 612                 case '\'':
 613                 case ']':
 614                 case ')':
 615                         if (0 == found)
 616                                 enclosed = 1;
 617                         break;
 618                 case '.':
 619                 case '!':
 620                 case '?':
 621                         found = 1;
 622                         break;
 623                 default:
 624                         return found &&
 625                             (!enclosed || isalnum((unsigned char)*q));
 626                 }
 627         }
 628
 629         return found && !enclosed;
 630 }
 631
 632 /*
 633  * Convert a string to a long that may not be <0.
 634  * If the string is invalid, or is less than 0, return -1.
 635  */
 636 int
 637 mandoc_strntoi(const char *p, size_t sz, int base)
 638 {
 639         char             buf[32];
 640         char            *ep;
 641         long             v;
 642
 643         if (sz > 31)
 644                 return -1;
 645
 646         memcpy(buf, p, sz);
 647         buf[(int)sz] = '\0';
 648
 649         errno = 0;
 650         v = strtol(buf, &ep, base);
 651
 652         if (buf[0] == '\0' || *ep != '\0')
 653                 return -1;
 654
 655         if (v > INT_MAX)
 656                 v = INT_MAX;
 657         if (v < INT_MIN)
 658                 v = INT_MIN;
 659
 660         return (int)v;
 661 }