mandoc.c

   1 /*      $Id: mandoc.c,v 1.53 2011/05/24 21:31:23 kristaps Exp $ */
   2 /*
   3  * Copyright (c) 2008, 2009, 2010 Kristaps Dzonsons <kristaps@bsd.lv>
   4  * Copyright (c) 2011 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 #ifdef HAVE_CONFIG_H
  19 #include "config.h"
  20 #endif
  21
  22 #include <sys/types.h>
  23
  24 #include <assert.h>
  25 #include <ctype.h>
  26 #include <errno.h>
  27 #include <limits.h>
  28 #include <stdlib.h>
  29 #include <stdio.h>
  30 #include <string.h>
  31 #include <time.h>
  32
  33 #include "mandoc.h"
  34 #include "libmandoc.h"
  35
  36 #define DATESIZE 32
  37
  38 static  int      a2time(time_t *, const char *, const char *);
  39 static  char    *time2a(time_t);
  40 static  int      numescape(const char *);
  41
  42 /*
  43  * Pass over recursive numerical expressions.  This context of this
  44  * function is important: it's only called within character-terminating
  45  * escapes (e.g., \s[xxxyyy]), so all we need to do is handle initial
  46  * recursion: we don't care about what's in these blocks.
  47  * This returns the number of characters skipped or -1 if an error
  48  * occurs (the caller should bail).
  49  */
  50 static int
  51 numescape(const char *start)
  52 {
  53         int              i;
  54         size_t           sz;
  55         const char      *cp;
  56
  57         i = 0;
  58
  59         /* The expression consists of a subexpression. */
  60
  61         if ('\\' == start[i]) {
  62                 cp = &start[++i];
  63                 /*
  64                  * Read past the end of the subexpression.
  65                  * Bail immediately on errors.
  66                  */
  67                 if (ESCAPE_ERROR == mandoc_escape(&cp, NULL, NULL))
  68                         return(-1);
  69                 return(i + cp - &start[i]);
  70         }
  71
  72         if ('(' != start[i++])
  73                 return(0);
  74
  75         /*
  76          * A parenthesised subexpression.  Read until the closing
  77          * parenthesis, making sure to handle any nested subexpressions
  78          * that might ruin our parse.
  79          */
  80
  81         while (')' != start[i]) {
  82                 sz = strcspn(&start[i], ")\\");
  83                 i += (int)sz;
  84
  85                 if ('\0' == start[i])
  86                         return(-1);
  87                 else if ('\\' != start[i])
  88                         continue;
  89
  90                 cp = &start[++i];
  91                 if (ESCAPE_ERROR == mandoc_escape(&cp, NULL, NULL))
  92                         return(-1);
  93                 i += cp - &start[i];
  94         }
  95
  96         /* Read past the terminating ')'. */
  97         return(++i);
  98 }
  99
 100 enum mandoc_esc
 101 mandoc_escape(const char **end, const char **start, int *sz)
 102 {
 103         char             c, term, numeric;
 104         int              i, lim, ssz, rlim;
 105         const char      *cp, *rstart;
 106         enum mandoc_esc  gly;
 107
 108         cp = *end;
 109         rstart = cp;
 110         if (start)
 111                 *start = rstart;
 112         i = lim = 0;
 113         gly = ESCAPE_ERROR;
 114         term = numeric = '\0';
 115
 116         switch ((c = cp[i++])) {
 117         /*
 118          * First the glyphs.  There are several different forms of
 119          * these, but each eventually returns a substring of the glyph
 120          * name.
 121          */
 122         case ('('):
 123                 gly = ESCAPE_SPECIAL;
 124                 lim = 2;
 125                 break;
 126         case ('['):
 127                 gly = ESCAPE_SPECIAL;
 128                 /*
 129                  * Unicode escapes are defined in groff as \[uXXXX] to
 130                  * \[u10FFFF], where the contained value must be a valid
 131                  * Unicode codepoint.  Here, however, only check whether
 132                  * it's not a zero-width escape.
 133                  */
 134                 if ('u' == cp[i] && ']' != cp[i + 1])
 135                         gly = ESCAPE_UNICODE;
 136                 term = ']';
 137                 break;
 138         case ('C'):
 139                 if ('\'' != cp[i])
 140                         return(ESCAPE_ERROR);
 141                 gly = ESCAPE_SPECIAL;
 142                 term = '\'';
 143                 break;
 144
 145         /*
 146          * Handle all triggers matching \X(xy, \Xx, and \X[xxxx], where
 147          * 'X' is the trigger.  These have opaque sub-strings.
 148          */
 149         case ('F'):
 150                 /* FALLTHROUGH */
 151         case ('g'):
 152                 /* FALLTHROUGH */
 153         case ('k'):
 154                 /* FALLTHROUGH */
 155         case ('M'):
 156                 /* FALLTHROUGH */
 157         case ('m'):
 158                 /* FALLTHROUGH */
 159         case ('n'):
 160                 /* FALLTHROUGH */
 161         case ('V'):
 162                 /* FALLTHROUGH */
 163         case ('Y'):
 164                 if (ESCAPE_ERROR == gly)
 165                         gly = ESCAPE_IGNORE;
 166                 /* FALLTHROUGH */
 167         case ('f'):
 168                 if (ESCAPE_ERROR == gly)
 169                         gly = ESCAPE_FONT;
 170
 171                 rstart= &cp[i];
 172                 if (start)
 173                         *start = rstart;
 174
 175                 switch (cp[i++]) {
 176                 case ('('):
 177                         lim = 2;
 178                         break;
 179                 case ('['):
 180                         term = ']';
 181                         break;
 182                 default:
 183                         lim = 1;
 184                         i--;
 185                         break;
 186                 }
 187                 break;
 188
 189         /*
 190          * These escapes are of the form \X'Y', where 'X' is the trigger
 191          * and 'Y' is any string.  These have opaque sub-strings.
 192          */
 193         case ('A'):
 194                 /* FALLTHROUGH */
 195         case ('b'):
 196                 /* FALLTHROUGH */
 197         case ('D'):
 198                 /* FALLTHROUGH */
 199         case ('o'):
 200                 /* FALLTHROUGH */
 201         case ('R'):
 202                 /* FALLTHROUGH */
 203         case ('X'):
 204                 /* FALLTHROUGH */
 205         case ('Z'):
 206                 if ('\'' != cp[i++])
 207                         return(ESCAPE_ERROR);
 208                 gly = ESCAPE_IGNORE;
 209                 term = '\'';
 210                 break;
 211
 212         /*
 213          * These escapes are of the form \X'N', where 'X' is the trigger
 214          * and 'N' resolves to a numerical expression.
 215          */
 216         case ('B'):
 217                 /* FALLTHROUGH */
 218         case ('h'):
 219                 /* FALLTHROUGH */
 220         case ('H'):
 221                 /* FALLTHROUGH */
 222         case ('L'):
 223                 /* FALLTHROUGH */
 224         case ('l'):
 225                 /* FALLTHROUGH */
 226         case ('N'):
 227                 if (ESCAPE_ERROR == gly)
 228                         gly = ESCAPE_NUMBERED;
 229                 /* FALLTHROUGH */
 230         case ('S'):
 231                 /* FALLTHROUGH */
 232         case ('v'):
 233                 /* FALLTHROUGH */
 234         case ('w'):
 235                 /* FALLTHROUGH */
 236         case ('x'):
 237                 if (ESCAPE_ERROR == gly)
 238                         gly = ESCAPE_IGNORE;
 239                 if ('\'' != cp[i++])
 240                         return(ESCAPE_ERROR);
 241                 term = numeric = '\'';
 242                 break;
 243
 244         /*
 245          * Sizes get a special category of their own.
 246          */
 247         case ('s'):
 248                 gly = ESCAPE_IGNORE;
 249
 250                 rstart = &cp[i];
 251                 if (start)
 252                         *start = rstart;
 253
 254                 /* See +/- counts as a sign. */
 255                 c = cp[i];
 256                 if ('+' == c || '-' == c || ASCII_HYPH == c)
 257                         ++i;
 258
 259                 switch (cp[i++]) {
 260                 case ('('):
 261                         lim = 2;
 262                         break;
 263                 case ('['):
 264                         term = numeric = ']';
 265                         break;
 266                 case ('\''):
 267                         term = numeric = '\'';
 268                         break;
 269                 default:
 270                         lim = 1;
 271                         i--;
 272                         break;
 273                 }
 274
 275                 /* See +/- counts as a sign. */
 276                 c = cp[i];
 277                 if ('+' == c || '-' == c || ASCII_HYPH == c)
 278                         ++i;
 279
 280                 break;
 281
 282         /*
 283          * Anything else is assumed to be a glyph.
 284          */
 285         default:
 286                 gly = ESCAPE_SPECIAL;
 287                 lim = 1;
 288                 i--;
 289                 break;
 290         }
 291
 292         assert(ESCAPE_ERROR != gly);
 293
 294         rstart = &cp[i];
 295         if (start)
 296                 *start = rstart;
 297
 298         /*
 299          * If a terminating block has been specified, we need to
 300          * handle the case of recursion, which could have their
 301          * own terminating blocks that mess up our parse.  This, by the
 302          * way, means that the "start" and "size" values will be
 303          * effectively meaningless.
 304          */
 305
 306         ssz = 0;
 307         if (numeric && -1 == (ssz = numescape(&cp[i])))
 308                 return(ESCAPE_ERROR);
 309
 310         i += ssz;
 311         rlim = -1;
 312
 313         /*
 314          * We have a character terminator.  Try to read up to that
 315          * character.  If we can't (i.e., we hit the nil), then return
 316          * an error; if we can, calculate our length, read past the
 317          * terminating character, and exit.
 318          */
 319
 320         if ('\0' != term) {
 321                 *end = strchr(&cp[i], term);
 322                 if ('\0' == *end)
 323                         return(ESCAPE_ERROR);
 324
 325                 rlim = *end - &cp[i];
 326                 if (sz)
 327                         *sz = rlim;
 328                 (*end)++;
 329                 goto out;
 330         }
 331
 332         assert(lim > 0);
 333
 334         /*
 335          * We have a numeric limit.  If the string is shorter than that,
 336          * stop and return an error.  Else adjust our endpoint, length,
 337          * and return the current glyph.
 338          */
 339
 340         if ((size_t)lim > strlen(&cp[i]))
 341                 return(ESCAPE_ERROR);
 342
 343         rlim = lim;
 344         if (sz)
 345                 *sz = rlim;
 346
 347         *end = &cp[i] + lim;
 348
 349 out:
 350         assert(rlim >= 0 && rstart);
 351
 352         /* Run post-processors. */
 353
 354         switch (gly) {
 355         case (ESCAPE_FONT):
 356                 if (1 != rlim)
 357                         break;
 358                 switch (*rstart) {
 359                 case ('3'):
 360                         /* FALLTHROUGH */
 361                 case ('B'):
 362                         gly = ESCAPE_FONTBOLD;
 363                         break;
 364                 case ('2'):
 365                         /* FALLTHROUGH */
 366                 case ('I'):
 367                         gly = ESCAPE_FONTITALIC;
 368                         break;
 369                 case ('P'):
 370                         gly = ESCAPE_FONTPREV;
 371                         break;
 372                 case ('1'):
 373                         /* FALLTHROUGH */
 374                 case ('R'):
 375                         gly = ESCAPE_FONTROMAN;
 376                         break;
 377                 }
 378                 break;
 379         case (ESCAPE_SPECIAL):
 380                 if (1 != rlim)
 381                         break;
 382                 if ('c' == *rstart)
 383                         gly = ESCAPE_NOSPACE;
 384                 break;
 385         default:
 386                 break;
 387         }
 388
 389         return(gly);
 390 }
 391
 392 void *
 393 mandoc_calloc(size_t num, size_t size)
 394 {
 395         void            *ptr;
 396
 397         ptr = calloc(num, size);
 398         if (NULL == ptr) {
 399                 perror(NULL);
 400                 exit((int)MANDOCLEVEL_SYSERR);
 401         }
 402
 403         return(ptr);
 404 }
 405
 406
 407 void *
 408 mandoc_malloc(size_t size)
 409 {
 410         void            *ptr;
 411
 412         ptr = malloc(size);
 413         if (NULL == ptr) {
 414                 perror(NULL);
 415                 exit((int)MANDOCLEVEL_SYSERR);
 416         }
 417
 418         return(ptr);
 419 }
 420
 421
 422 void *
 423 mandoc_realloc(void *ptr, size_t size)
 424 {
 425
 426         ptr = realloc(ptr, size);
 427         if (NULL == ptr) {
 428                 perror(NULL);
 429                 exit((int)MANDOCLEVEL_SYSERR);
 430         }
 431
 432         return(ptr);
 433 }
 434
 435
 436 char *
 437 mandoc_strdup(const char *ptr)
 438 {
 439         char            *p;
 440
 441         p = strdup(ptr);
 442         if (NULL == p) {
 443                 perror(NULL);
 444                 exit((int)MANDOCLEVEL_SYSERR);
 445         }
 446
 447         return(p);
 448 }
 449
 450 /*
 451  * Parse a quoted or unquoted roff-style request or macro argument.
 452  * Return a pointer to the parsed argument, which is either the original
 453  * pointer or advanced by one byte in case the argument is quoted.
 454  * Null-terminate the argument in place.
 455  * Collapse pairs of quotes inside quoted arguments.
 456  * Advance the argument pointer to the next argument,
 457  * or to the null byte terminating the argument line.
 458  */
 459 char *
 460 mandoc_getarg(struct mparse *parse, char **cpp, int ln, int *pos)
 461 {
 462         char     *start, *cp;
 463         int       quoted, pairs, white;
 464
 465         /* Quoting can only start with a new word. */
 466         start = *cpp;
 467         quoted = 0;
 468         if ('"' == *start) {
 469                 quoted = 1;
 470                 start++;
 471         }
 472
 473         pairs = 0;
 474         white = 0;
 475         for (cp = start; '\0' != *cp; cp++) {
 476                 /* Move left after quoted quotes and escaped backslashes. */
 477                 if (pairs)
 478                         cp[-pairs] = cp[0];
 479                 if ('\\' == cp[0]) {
 480                         if ('\\' == cp[1]) {
 481                                 /* Poor man's copy mode. */
 482                                 pairs++;
 483                                 cp++;
 484                         } else if (0 == quoted && ' ' == cp[1])
 485                                 /* Skip escaped blanks. */
 486                                 cp++;
 487                 } else if (0 == quoted) {
 488                         if (' ' == cp[0]) {
 489                                 /* Unescaped blanks end unquoted args. */
 490                                 white = 1;
 491                                 break;
 492                         }
 493                 } else if ('"' == cp[0]) {
 494                         if ('"' == cp[1]) {
 495                                 /* Quoted quotes collapse. */
 496                                 pairs++;
 497                                 cp++;
 498                         } else {
 499                                 /* Unquoted quotes end quoted args. */
 500                                 quoted = 2;
 501                                 break;
 502                         }
 503                 }
 504         }
 505
 506         /* Quoted argument without a closing quote. */
 507         if (1 == quoted)
 508                 mandoc_msg(MANDOCERR_BADQUOTE, parse, ln, *pos, NULL);
 509
 510         /* Null-terminate this argument and move to the next one. */
 511         if (pairs)
 512                 cp[-pairs] = '\0';
 513         if ('\0' != *cp) {
 514                 *cp++ = '\0';
 515                 while (' ' == *cp)
 516                         cp++;
 517         }
 518         *pos += (int)(cp - start) + (quoted ? 1 : 0);
 519         *cpp = cp;
 520
 521         if ('\0' == *cp && (white || ' ' == cp[-1]))
 522                 mandoc_msg(MANDOCERR_EOLNSPACE, parse, ln, *pos, NULL);
 523
 524         return(start);
 525 }
 526
 527 static int
 528 a2time(time_t *t, const char *fmt, const char *p)
 529 {
 530         struct tm        tm;
 531         char            *pp;
 532
 533         memset(&tm, 0, sizeof(struct tm));
 534
 535         pp = strptime(p, fmt, &tm);
 536         if (NULL != pp && '\0' == *pp) {
 537                 *t = mktime(&tm);
 538                 return(1);
 539         }
 540
 541         return(0);
 542 }
 543
 544 static char *
 545 time2a(time_t t)
 546 {
 547         struct tm        tm;
 548         char            *buf, *p;
 549         size_t           ssz;
 550         int              isz;
 551
 552         localtime_r(&t, &tm);
 553
 554         /*
 555          * Reserve space:
 556          * up to 9 characters for the month (September) + blank
 557          * up to 2 characters for the day + comma + blank
 558          * 4 characters for the year and a terminating '\0'
 559          */
 560         p = buf = mandoc_malloc(10 + 4 + 4 + 1);
 561
 562         if (0 == (ssz = strftime(p, 10 + 1, "%B ", &tm)))
 563                 goto fail;
 564         p += (int)ssz;
 565
 566         if (-1 == (isz = snprintf(p, 4 + 1, "%d, ", tm.tm_mday)))
 567                 goto fail;
 568         p += isz;
 569
 570         if (0 == strftime(p, 4 + 1, "%Y", &tm))
 571                 goto fail;
 572         return(buf);
 573
 574 fail:
 575         free(buf);
 576         return(NULL);
 577 }
 578
 579 char *
 580 mandoc_normdate(struct mparse *parse, char *in, int ln, int pos)
 581 {
 582         char            *out;
 583         time_t           t;
 584
 585         if (NULL == in || '\0' == *in ||
 586             0 == strcmp(in, "$" "Mdocdate$")) {
 587                 mandoc_msg(MANDOCERR_NODATE, parse, ln, pos, NULL);
 588                 time(&t);
 589         }
 590         else if (!a2time(&t, "$" "Mdocdate: %b %d %Y $", in) &&
 591             !a2time(&t, "%b %d, %Y", in) &&
 592             !a2time(&t, "%Y-%m-%d", in)) {
 593                 mandoc_msg(MANDOCERR_BADDATE, parse, ln, pos, NULL);
 594                 t = 0;
 595         }
 596         out = t ? time2a(t) : NULL;
 597         return(out ? out : mandoc_strdup(in));
 598 }
 599
 600 int
 601 mandoc_eos(const char *p, size_t sz, int enclosed)
 602 {
 603         const char *q;
 604         int found;
 605
 606         if (0 == sz)
 607                 return(0);
 608
 609         /*
 610          * End-of-sentence recognition must include situations where
 611          * some symbols, such as `)', allow prior EOS punctuation to
 612          * propagate outward.
 613          */
 614
 615         found = 0;
 616         for (q = p + (int)sz - 1; q >= p; q--) {
 617                 switch (*q) {
 618                 case ('\"'):
 619                         /* FALLTHROUGH */
 620                 case ('\''):
 621                         /* FALLTHROUGH */
 622                 case (']'):
 623                         /* FALLTHROUGH */
 624                 case (')'):
 625                         if (0 == found)
 626                                 enclosed = 1;
 627                         break;
 628                 case ('.'):
 629                         /* FALLTHROUGH */
 630                 case ('!'):
 631                         /* FALLTHROUGH */
 632                 case ('?'):
 633                         found = 1;
 634                         break;
 635                 default:
 636                         return(found && (!enclosed || isalnum((unsigned char)*q)));
 637                 }
 638         }
 639
 640         return(found && !enclosed);
 641 }
 642
 643 int
 644 mandoc_hyph(const char *start, const char *c)
 645 {
 646
 647         /*
 648          * Choose whether to break at a hyphenated character.  We only
 649          * do this if it's free-standing within a word.
 650          */
 651
 652         /* Skip first/last character of buffer. */
 653         if (c == start || '\0' == *(c + 1))
 654                 return(0);
 655         /* Skip first/last character of word. */
 656         if ('\t' == *(c + 1) || '\t' == *(c - 1))
 657                 return(0);
 658         if (' ' == *(c + 1) || ' ' == *(c - 1))
 659                 return(0);
 660         /* Skip double invocations. */
 661         if ('-' == *(c + 1) || '-' == *(c - 1))
 662                 return(0);
 663         /* Skip escapes. */
 664         if ('\\' == *(c - 1))
 665                 return(0);
 666
 667         return(1);
 668 }
 669
 670 /*
 671  * Find out whether a line is a macro line or not.  If it is, adjust the
 672  * current position and return one; if it isn't, return zero and don't
 673  * change the current position.
 674  */
 675 int
 676 mandoc_getcontrol(const char *cp, int *ppos)
 677 {
 678         int             pos;
 679
 680         pos = *ppos;
 681
 682         if ('\\' == cp[pos] && '.' == cp[pos + 1])
 683                 pos += 2;
 684         else if ('.' == cp[pos] || '\'' == cp[pos])
 685                 pos++;
 686         else
 687                 return(0);
 688
 689         while (' ' == cp[pos] || '\t' == cp[pos])
 690                 pos++;
 691
 692         *ppos = pos;
 693         return(1);
 694 }
 695
 696 /*
 697  * Convert a string to a long that may not be <0.
 698  * If the string is invalid, or is less than 0, return -1.
 699  */
 700 int
 701 mandoc_strntou(const char *p, size_t sz, int base)
 702 {
 703         char             buf[32];
 704         char            *ep;
 705         long             v;
 706
 707         if (sz > 31)
 708                 return(-1);
 709
 710         memcpy(buf, p, sz);
 711         buf[(int)sz] = '\0';
 712
 713         errno = 0;
 714         v = strtol(buf, &ep, base);
 715
 716         if (buf[0] == '\0' || *ep != '\0')
 717                 return(-1);
 718
 719         if ((errno == ERANGE &&
 720                         (v == LONG_MAX || v == LONG_MIN)) ||
 721                         (v > INT_MAX || v < 0))
 722                 return(-1);
 723
 724         return((int)v);
 725 }
 726