mandoc.c

   1 /*      $Id: mandoc.c,v 1.58 2011/07/27 07:32:26 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 char *
 436 mandoc_strndup(const char *ptr, size_t sz)
 437 {
 438         char            *p;
 439
 440         p = mandoc_malloc(sz + 1);
 441         memcpy(p, ptr, sz);
 442         p[(int)sz] = '\0';
 443         return(p);
 444 }
 445
 446 char *
 447 mandoc_strdup(const char *ptr)
 448 {
 449         char            *p;
 450
 451         p = strdup(ptr);
 452         if (NULL == p) {
 453                 perror(NULL);
 454                 exit((int)MANDOCLEVEL_SYSERR);
 455         }
 456
 457         return(p);
 458 }
 459
 460 /*
 461  * Parse a quoted or unquoted roff-style request or macro argument.
 462  * Return a pointer to the parsed argument, which is either the original
 463  * pointer or advanced by one byte in case the argument is quoted.
 464  * Null-terminate the argument in place.
 465  * Collapse pairs of quotes inside quoted arguments.
 466  * Advance the argument pointer to the next argument,
 467  * or to the null byte terminating the argument line.
 468  */
 469 char *
 470 mandoc_getarg(struct mparse *parse, char **cpp, int ln, int *pos)
 471 {
 472         char     *start, *cp;
 473         int       quoted, pairs, white;
 474
 475         /* Quoting can only start with a new word. */
 476         start = *cpp;
 477         quoted = 0;
 478         if ('"' == *start) {
 479                 quoted = 1;
 480                 start++;
 481         }
 482
 483         pairs = 0;
 484         white = 0;
 485         for (cp = start; '\0' != *cp; cp++) {
 486                 /* Move left after quoted quotes and escaped backslashes. */
 487                 if (pairs)
 488                         cp[-pairs] = cp[0];
 489                 if ('\\' == cp[0]) {
 490                         if ('\\' == cp[1]) {
 491                                 /* Poor man's copy mode. */
 492                                 pairs++;
 493                                 cp++;
 494                         } else if (0 == quoted && ' ' == cp[1])
 495                                 /* Skip escaped blanks. */
 496                                 cp++;
 497                 } else if (0 == quoted) {
 498                         if (' ' == cp[0]) {
 499                                 /* Unescaped blanks end unquoted args. */
 500                                 white = 1;
 501                                 break;
 502                         }
 503                 } else if ('"' == cp[0]) {
 504                         if ('"' == cp[1]) {
 505                                 /* Quoted quotes collapse. */
 506                                 pairs++;
 507                                 cp++;
 508                         } else {
 509                                 /* Unquoted quotes end quoted args. */
 510                                 quoted = 2;
 511                                 break;
 512                         }
 513                 }
 514         }
 515
 516         /* Quoted argument without a closing quote. */
 517         if (1 == quoted)
 518                 mandoc_msg(MANDOCERR_BADQUOTE, parse, ln, *pos, NULL);
 519
 520         /* Null-terminate this argument and move to the next one. */
 521         if (pairs)
 522                 cp[-pairs] = '\0';
 523         if ('\0' != *cp) {
 524                 *cp++ = '\0';
 525                 while (' ' == *cp)
 526                         cp++;
 527         }
 528         *pos += (int)(cp - start) + (quoted ? 1 : 0);
 529         *cpp = cp;
 530
 531         if ('\0' == *cp && (white || ' ' == cp[-1]))
 532                 mandoc_msg(MANDOCERR_EOLNSPACE, parse, ln, *pos, NULL);
 533
 534         return(start);
 535 }
 536
 537 static int
 538 a2time(time_t *t, const char *fmt, const char *p)
 539 {
 540         struct tm        tm;
 541         char            *pp;
 542
 543         memset(&tm, 0, sizeof(struct tm));
 544
 545         pp = NULL;
 546 #ifdef  HAVE_STRPTIME
 547         pp = strptime(p, fmt, &tm);
 548 #endif
 549         if (NULL != pp && '\0' == *pp) {
 550                 *t = mktime(&tm);
 551                 return(1);
 552         }
 553
 554         return(0);
 555 }
 556
 557 static char *
 558 time2a(time_t t)
 559 {
 560         struct tm       *tm;
 561         char            *buf, *p;
 562         size_t           ssz;
 563         int              isz;
 564
 565         tm = localtime(&t);
 566
 567         /*
 568          * Reserve space:
 569          * up to 9 characters for the month (September) + blank
 570          * up to 2 characters for the day + comma + blank
 571          * 4 characters for the year and a terminating '\0'
 572          */
 573         p = buf = mandoc_malloc(10 + 4 + 4 + 1);
 574
 575         if (0 == (ssz = strftime(p, 10 + 1, "%B ", tm)))
 576                 goto fail;
 577         p += (int)ssz;
 578
 579         if (-1 == (isz = snprintf(p, 4 + 1, "%d, ", tm->tm_mday)))
 580                 goto fail;
 581         p += isz;
 582
 583         if (0 == strftime(p, 4 + 1, "%Y", tm))
 584                 goto fail;
 585         return(buf);
 586
 587 fail:
 588         free(buf);
 589         return(NULL);
 590 }
 591
 592 char *
 593 mandoc_normdate(struct mparse *parse, char *in, int ln, int pos)
 594 {
 595         char            *out;
 596         time_t           t;
 597
 598         if (NULL == in || '\0' == *in ||
 599             0 == strcmp(in, "$" "Mdocdate$")) {
 600                 mandoc_msg(MANDOCERR_NODATE, parse, ln, pos, NULL);
 601                 time(&t);
 602         }
 603         else if (!a2time(&t, "$" "Mdocdate: %b %d %Y $", in) &&
 604             !a2time(&t, "%b %d, %Y", in) &&
 605             !a2time(&t, "%Y-%m-%d", in)) {
 606                 mandoc_msg(MANDOCERR_BADDATE, parse, ln, pos, NULL);
 607                 t = 0;
 608         }
 609         out = t ? time2a(t) : NULL;
 610         return(out ? out : mandoc_strdup(in));
 611 }
 612
 613 int
 614 mandoc_eos(const char *p, size_t sz, int enclosed)
 615 {
 616         const char *q;
 617         int found;
 618
 619         if (0 == sz)
 620                 return(0);
 621
 622         /*
 623          * End-of-sentence recognition must include situations where
 624          * some symbols, such as `)', allow prior EOS punctuation to
 625          * propagate outward.
 626          */
 627
 628         found = 0;
 629         for (q = p + (int)sz - 1; q >= p; q--) {
 630                 switch (*q) {
 631                 case ('\"'):
 632                         /* FALLTHROUGH */
 633                 case ('\''):
 634                         /* FALLTHROUGH */
 635                 case (']'):
 636                         /* FALLTHROUGH */
 637                 case (')'):
 638                         if (0 == found)
 639                                 enclosed = 1;
 640                         break;
 641                 case ('.'):
 642                         /* FALLTHROUGH */
 643                 case ('!'):
 644                         /* FALLTHROUGH */
 645                 case ('?'):
 646                         found = 1;
 647                         break;
 648                 default:
 649                         return(found && (!enclosed || isalnum((unsigned char)*q)));
 650                 }
 651         }
 652
 653         return(found && !enclosed);
 654 }
 655
 656 /*
 657  * Find out whether a line is a macro line or not.  If it is, adjust the
 658  * current position and return one; if it isn't, return zero and don't
 659  * change the current position.
 660  */
 661 int
 662 mandoc_getcontrol(const char *cp, int *ppos)
 663 {
 664         int             pos;
 665
 666         pos = *ppos;
 667
 668         if ('\\' == cp[pos] && '.' == cp[pos + 1])
 669                 pos += 2;
 670         else if ('.' == cp[pos] || '\'' == cp[pos])
 671                 pos++;
 672         else
 673                 return(0);
 674
 675         while (' ' == cp[pos] || '\t' == cp[pos])
 676                 pos++;
 677
 678         *ppos = pos;
 679         return(1);
 680 }
 681
 682 /*
 683  * Convert a string to a long that may not be <0.
 684  * If the string is invalid, or is less than 0, return -1.
 685  */
 686 int
 687 mandoc_strntoi(const char *p, size_t sz, int base)
 688 {
 689         char             buf[32];
 690         char            *ep;
 691         long             v;
 692
 693         if (sz > 31)
 694                 return(-1);
 695
 696         memcpy(buf, p, sz);
 697         buf[(int)sz] = '\0';
 698
 699         errno = 0;
 700         v = strtol(buf, &ep, base);
 701
 702         if (buf[0] == '\0' || *ep != '\0')
 703                 return(-1);
 704
 705         if (v > INT_MAX)
 706                 v = INT_MAX;
 707         if (v < INT_MIN)
 708                 v = INT_MIN;
 709
 710         return((int)v);
 711 }