lib/roken/glob.c

   1 /*
   2  * Copyright (c) 1989, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * This code is derived from software contributed to Berkeley by
   6  * Guido van Rossum.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  * 3. Neither the name of the University nor the names of its contributors
  17  *    may be used to endorse or promote products derived from this software
  18  *    without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  */
  32
  33 /*
  34  * glob(3) -- a superset of the one defined in POSIX 1003.2.
  35  *
  36  * The [!...] convention to negate a range is supported (SysV, Posix, ksh).
  37  *
  38  * Optional extra services, controlled by flags not defined by POSIX:
  39  *
  40  * GLOB_QUOTE:
  41  *      Escaping convention: \ inhibits any special meaning the following
  42  *      character might have (except \ at end of string is retained).
  43  * GLOB_MAGCHAR:
  44  *      Set in gl_flags if pattern contained a globbing character.
  45  * GLOB_NOMAGIC:
  46  *      Same as GLOB_NOCHECK, but it will only append pattern if it did
  47  *      not contain any magic characters.  [Used in csh style globbing]
  48  * GLOB_ALTDIRFUNC:
  49  *      Use alternately specified directory access functions.
  50  * GLOB_TILDE:
  51  *      expand ~user/foo to the /home/dir/of/user/foo
  52  * GLOB_BRACE:
  53  *      expand {1,2}{a,b} to 1a 1b 2a 2b
  54  * gl_matchc:
  55  *      Number of matches in the current invocation of glob.
  56  */
  57
  58 #include <config.h>
  59
  60 #ifdef HAVE_SYS_PARAM_H
  61 #include <sys/param.h>
  62 #endif
  63 #ifdef HAVE_SYS_TYPES_H
  64 #include <sys/types.h>
  65 #endif
  66 #ifdef HAVE_SYS_STAT_H
  67 #include <sys/stat.h>
  68 #endif
  69
  70 #include <ctype.h>
  71 #ifdef HAVE_DIRENT_H
  72 #include <dirent.h>
  73 #endif
  74 #include <errno.h>
  75 #ifdef HAVE_PWD_H
  76 #include <pwd.h>
  77 #endif
  78 #include <stdio.h>
  79 #include <stdlib.h>
  80 #include <string.h>
  81 #ifdef HAVE_UNISTD_H
  82 #include <unistd.h>
  83 #endif
  84 #ifdef HAVE_LIMITS_H
  85 #include <limits.h>
  86 #endif
  87
  88 #include "glob.h"
  89 #include "roken.h"
  90
  91 #ifndef ARG_MAX
  92 #define ARG_MAX _POSIX_ARG_MAX
  93 #endif
  94
  95 #define CHAR_DOLLAR             '$'
  96 #define CHAR_DOT                '.'
  97 #define CHAR_EOS                '\0'
  98 #define CHAR_LBRACKET           '['
  99 #define CHAR_NOT                '!'
 100 #define CHAR_QUESTION           '?'
 101 #define CHAR_QUOTE              '\\'
 102 #define CHAR_RANGE              '-'
 103 #define CHAR_RBRACKET           ']'
 104 #define CHAR_SEP                '/'
 105 #define CHAR_STAR               '*'
 106 #define CHAR_TILDE              '~'
 107 #define CHAR_UNDERSCORE         '_'
 108 #define CHAR_LBRACE             '{'
 109 #define CHAR_RBRACE             '}'
 110 #define CHAR_SLASH              '/'
 111 #define CHAR_COMMA              ','
 112
 113 #ifndef DEBUG
 114
 115 #define M_QUOTE         0x8000
 116 #define M_PROTECT       0x4000
 117 #define M_MASK          0xffff
 118 #define M_ASCII         0x00ff
 119
 120 typedef u_short Char;
 121
 122 #else
 123
 124 #define M_QUOTE         0x80
 125 #define M_PROTECT       0x40
 126 #define M_MASK          0xff
 127 #define M_ASCII         0x7f
 128
 129 typedef char Char;
 130
 131 #endif
 132
 133
 134 #define CHAR(c)         ((Char)((c)&M_ASCII))
 135 #define META(c)         ((Char)((c)|M_QUOTE))
 136 #define M_ALL           META('*')
 137 #define M_END           META(']')
 138 #define M_NOT           META('!')
 139 #define M_ONE           META('?')
 140 #define M_RNG           META('-')
 141 #define M_SET           META('[')
 142 #define ismeta(c)       (((c)&M_QUOTE) != 0)
 143
 144
 145 static int       compare (const void *, const void *);
 146 static void      g_Ctoc (const Char *, char *);
 147 static int       g_lstat (Char *, struct stat *, glob_t *);
 148 static DIR      *g_opendir (Char *, glob_t *);
 149 static Char     *g_strchr (const Char *, int);
 150 #ifdef notdef
 151 static Char     *g_strcat (Char *, const Char *);
 152 #endif
 153 static int       g_stat (Char *, struct stat *, glob_t *);
 154 static int       glob0 (const Char *, glob_t *);
 155 static int       glob1 (Char *, glob_t *, size_t *);
 156 static int       glob2 (Char *, Char *, Char *, glob_t *, size_t *);
 157 static int       glob3 (Char *, Char *, Char *, Char *, glob_t *, size_t *);
 158 static int       globextend (const Char *, glob_t *, size_t *);
 159 static const Char *      globtilde (const Char *, Char *, glob_t *);
 160 static int       globexp1 (const Char *, glob_t *);
 161 static int       globexp2 (const Char *, const Char *, glob_t *, int *);
 162 static int       match (Char *, Char *, Char *);
 163 #ifdef DEBUG
 164 static void      qprintf (const char *, Char *);
 165 #endif
 166
 167 ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
 168 glob(const char *pattern,
 169      int flags,
 170      int (*errfunc)(const char *, int),
 171      glob_t *pglob)
 172 {
 173         const u_char *patnext;
 174         int c;
 175         Char *bufnext, *bufend, patbuf[MaxPathLen+1];
 176
 177         patnext = (const u_char *) pattern;
 178         if (!(flags & GLOB_APPEND)) {
 179                 pglob->gl_pathc = 0;
 180                 pglob->gl_pathv = NULL;
 181                 if (!(flags & GLOB_DOOFFS))
 182                         pglob->gl_offs = 0;
 183         }
 184         pglob->gl_flags = flags & ~GLOB_MAGCHAR;
 185         pglob->gl_errfunc = errfunc;
 186         pglob->gl_matchc = 0;
 187
 188         bufnext = patbuf;
 189         bufend = bufnext + MaxPathLen;
 190         if (flags & GLOB_QUOTE) {
 191                 /* Protect the quoted characters. */
 192                 while (bufnext < bufend && (c = *patnext++) != CHAR_EOS)
 193                         if (c == CHAR_QUOTE) {
 194                                 if ((c = *patnext++) == CHAR_EOS) {
 195                                         c = CHAR_QUOTE;
 196                                         --patnext;
 197                                 }
 198                                 *bufnext++ = c | M_PROTECT;
 199                         }
 200                         else
 201                                 *bufnext++ = c;
 202         }
 203         else
 204             while (bufnext < bufend && (c = *patnext++) != CHAR_EOS)
 205                     *bufnext++ = c;
 206         *bufnext = CHAR_EOS;
 207
 208         if (flags & GLOB_BRACE)
 209             return globexp1(patbuf, pglob);
 210         else
 211             return glob0(patbuf, pglob);
 212 }
 213
 214 /*
 215  * Expand recursively a glob {} pattern. When there is no more expansion
 216  * invoke the standard globbing routine to glob the rest of the magic
 217  * characters
 218  */
 219 static int globexp1(const Char *pattern, glob_t *pglob)
 220 {
 221         const Char* ptr = pattern;
 222         int rv;
 223
 224         /* Protect a single {}, for find(1), like csh */
 225         if (pattern[0] == CHAR_LBRACE && pattern[1] == CHAR_RBRACE && pattern[2] == CHAR_EOS)
 226                 return glob0(pattern, pglob);
 227
 228         while ((ptr = (const Char *) g_strchr(ptr, CHAR_LBRACE)) != NULL)
 229                 if (!globexp2(ptr, pattern, pglob, &rv))
 230                         return rv;
 231
 232         return glob0(pattern, pglob);
 233 }
 234
 235
 236 /*
 237  * Recursive brace globbing helper. Tries to expand a single brace.
 238  * If it succeeds then it invokes globexp1 with the new pattern.
 239  * If it fails then it tries to glob the rest of the pattern and returns.
 240  */
 241 static int globexp2(const Char *ptr, const Char *pattern,
 242                     glob_t *pglob, int *rv)
 243 {
 244         int     i;
 245         Char   *lm, *ls;
 246         const Char *pe, *pm, *pl;
 247         Char    patbuf[MaxPathLen + 1];
 248
 249         /* copy part up to the brace */
 250         for (lm = patbuf, pm = pattern; pm != ptr; *lm++ = *pm++)
 251                 continue;
 252         ls = lm;
 253
 254         /* Find the balanced brace */
 255         for (i = 0, pe = ++ptr; *pe; pe++)
 256                 if (*pe == CHAR_LBRACKET) {
 257                         /* Ignore everything between [] */
 258                         for (pm = pe++; *pe != CHAR_RBRACKET && *pe != CHAR_EOS; pe++)
 259                                 continue;
 260                         if (*pe == CHAR_EOS) {
 261                                 /*
 262                                  * We could not find a matching CHAR_RBRACKET.
 263                                  * Ignore and just look for CHAR_RBRACE
 264                                  */
 265                                 pe = pm;
 266                         }
 267                 }
 268                 else if (*pe == CHAR_LBRACE)
 269                         i++;
 270                 else if (*pe == CHAR_RBRACE) {
 271                         if (i == 0)
 272                                 break;
 273                         i--;
 274                 }
 275
 276         /* Non matching braces; just glob the pattern */
 277         if (i != 0 || *pe == CHAR_EOS) {
 278                 *rv = glob0(patbuf, pglob);
 279                 return 0;
 280         }
 281
 282         for (i = 0, pl = pm = ptr; pm <= pe; pm++)
 283                 switch (*pm) {
 284                 case CHAR_LBRACKET:
 285                         /* Ignore everything between [] */
 286                         for (pl = pm++; *pm != CHAR_RBRACKET && *pm != CHAR_EOS; pm++)
 287                                 continue;
 288                         if (*pm == CHAR_EOS) {
 289                                 /*
 290                                  * We could not find a matching CHAR_RBRACKET.
 291                                  * Ignore and just look for CHAR_RBRACE
 292                                  */
 293                                 pm = pl;
 294                         }
 295                         break;
 296
 297                 case CHAR_LBRACE:
 298                         i++;
 299                         break;
 300
 301                 case CHAR_RBRACE:
 302                         if (i) {
 303                             i--;
 304                             break;
 305                         }
 306                         /* FALLTHROUGH */
 307                 case CHAR_COMMA:
 308                         if (i && *pm == CHAR_COMMA)
 309                                 break;
 310                         else {
 311                                 /* Append the current string */
 312                                 for (lm = ls; (pl < pm); *lm++ = *pl++)
 313                                         continue;
 314                                 /*
 315                                  * Append the rest of the pattern after the
 316                                  * closing brace
 317                                  */
 318                                 for (pl = pe + 1; (*lm++ = *pl++) != CHAR_EOS;)
 319                                         continue;
 320
 321                                 /* Expand the current pattern */
 322 #ifdef DEBUG
 323                                 qprintf("globexp2:", patbuf);
 324 #endif
 325                                 *rv = globexp1(patbuf, pglob);
 326
 327                                 /* move after the comma, to the next string */
 328                                 pl = pm + 1;
 329                         }
 330                         break;
 331
 332                 default:
 333                         break;
 334                 }
 335         *rv = 0;
 336         return 0;
 337 }
 338
 339
 340
 341 /*
 342  * expand tilde from the passwd file.
 343  */
 344 static const Char *
 345 globtilde(const Char *pattern, Char *patbuf, glob_t *pglob)
 346 {
 347         struct passwd *pwd;
 348         char *h;
 349         const Char *p;
 350         Char *b;
 351
 352         if (*pattern != CHAR_TILDE || !(pglob->gl_flags & GLOB_TILDE))
 353                 return pattern;
 354
 355         /* Copy up to the end of the string or / */
 356         for (p = pattern + 1, h = (char *) patbuf; *p && *p != CHAR_SLASH;
 357              *h++ = *p++)
 358                 continue;
 359
 360         *h = CHAR_EOS;
 361
 362         if (((char *) patbuf)[0] == CHAR_EOS) {
 363                 /*
 364                  * handle a plain ~ or ~/ by expanding $HOME
 365                  * first and then trying the password file
 366                  */
 367                 if ((h = getenv("HOME")) == NULL) {
 368                         if ((pwd = k_getpwuid(getuid())) == NULL)
 369                                 return pattern;
 370                         else
 371                                 h = pwd->pw_dir;
 372                 }
 373         }
 374         else {
 375                 /*
 376                  * Expand a ~user
 377                  */
 378                 if ((pwd = k_getpwnam((char*) patbuf)) == NULL)
 379                         return pattern;
 380                 else
 381                         h = pwd->pw_dir;
 382         }
 383
 384         /* Copy the home directory */
 385         for (b = patbuf; *h; *b++ = *h++)
 386                 continue;
 387
 388         /* Append the rest of the pattern */
 389         while ((*b++ = *p++) != CHAR_EOS)
 390                 continue;
 391
 392         return patbuf;
 393 }
 394
 395
 396 /*
 397  * The main glob() routine: compiles the pattern (optionally processing
 398  * quotes), calls glob1() to do the real pattern matching, and finally
 399  * sorts the list (unless unsorted operation is requested).  Returns 0
 400  * if things went well, nonzero if errors occurred.  It is not an error
 401  * to find no matches.
 402  */
 403 static int
 404 glob0(const Char *pattern, glob_t *pglob)
 405 {
 406         const Char *qpatnext;
 407         int c, ret, oldpathc;
 408         Char *bufnext, patbuf[MaxPathLen+1];
 409         size_t limit = 0;
 410
 411         qpatnext = globtilde(pattern, patbuf, pglob);
 412         oldpathc = pglob->gl_pathc;
 413         bufnext = patbuf;
 414
 415         /* We don't need to check for buffer overflow any more. */
 416         while ((c = *qpatnext++) != CHAR_EOS) {
 417                 switch (c) {
 418                 case CHAR_LBRACKET:
 419                         c = *qpatnext;
 420                         if (c == CHAR_NOT)
 421                                 ++qpatnext;
 422                         if (*qpatnext == CHAR_EOS ||
 423                             g_strchr(qpatnext+1, CHAR_RBRACKET) == NULL) {
 424                                 *bufnext++ = CHAR_LBRACKET;
 425                                 if (c == CHAR_NOT)
 426                                         --qpatnext;
 427                                 break;
 428                         }
 429                         *bufnext++ = M_SET;
 430                         if (c == CHAR_NOT)
 431                                 *bufnext++ = M_NOT;
 432                         c = *qpatnext++;
 433                         do {
 434                                 *bufnext++ = CHAR(c);
 435                                 if (*qpatnext == CHAR_RANGE &&
 436                                     (c = qpatnext[1]) != CHAR_RBRACKET) {
 437                                         *bufnext++ = M_RNG;
 438                                         *bufnext++ = CHAR(c);
 439                                         qpatnext += 2;
 440                                 }
 441                         } while ((c = *qpatnext++) != CHAR_RBRACKET);
 442                         pglob->gl_flags |= GLOB_MAGCHAR;
 443                         *bufnext++ = M_END;
 444                         break;
 445                 case CHAR_QUESTION:
 446                         pglob->gl_flags |= GLOB_MAGCHAR;
 447                         *bufnext++ = M_ONE;
 448                         break;
 449                 case CHAR_STAR:
 450                         pglob->gl_flags |= GLOB_MAGCHAR;
 451                         /* collapse adjacent stars to one,
 452                          * to avoid exponential behavior
 453                          */
 454                         if (bufnext == patbuf || bufnext[-1] != M_ALL)
 455                             *bufnext++ = M_ALL;
 456                         break;
 457                 default:
 458                         *bufnext++ = CHAR(c);
 459                         break;
 460                 }
 461         }
 462         *bufnext = CHAR_EOS;
 463 #ifdef DEBUG
 464         qprintf("glob0:", patbuf);
 465 #endif
 466
 467         if ((ret = glob1(patbuf, pglob, &limit)) != 0)
 468                 return(ret);
 469
 470         /*
 471          * If there was no match we are going to append the pattern
 472          * if GLOB_NOCHECK was specified or if GLOB_NOMAGIC was specified
 473          * and the pattern did not contain any magic characters
 474          * GLOB_NOMAGIC is there just for compatibility with csh.
 475          */
 476         if (pglob->gl_pathc == oldpathc &&
 477             ((pglob->gl_flags & GLOB_NOCHECK) ||
 478               ((pglob->gl_flags & GLOB_NOMAGIC) &&
 479                !(pglob->gl_flags & GLOB_MAGCHAR))))
 480                 return(globextend(pattern, pglob, &limit));
 481         else if (!(pglob->gl_flags & GLOB_NOSORT))
 482                 qsort(pglob->gl_pathv + pglob->gl_offs + oldpathc,
 483                     pglob->gl_pathc - oldpathc, sizeof(char *), compare);
 484         return(0);
 485 }
 486
 487 static int
 488 compare(const void *p, const void *q)
 489 {
 490         return(strcmp(*(char **)p, *(char **)q));
 491 }
 492
 493 static int
 494 glob1(Char *pattern, glob_t *pglob, size_t *limit)
 495 {
 496         Char pathbuf[MaxPathLen+1];
 497
 498         /* A null pathname is invalid -- POSIX 1003.1 sect. 2.4. */
 499         if (*pattern == CHAR_EOS)
 500                 return(0);
 501         return(glob2(pathbuf, pathbuf, pattern, pglob, limit));
 502 }
 503
 504 /*
 505  * The functions glob2 and glob3 are mutually recursive; there is one level
 506  * of recursion for each segment in the pattern that contains one or more
 507  * meta characters.
 508  */
 509
 510 #ifndef S_ISLNK
 511 #if defined(S_IFLNK) && defined(S_IFMT)
 512 #define S_ISLNK(mode) (((mode) & S_IFMT) == S_IFLNK)
 513 #else
 514 #define S_ISLNK(mode) 0
 515 #endif
 516 #endif
 517
 518 static int
 519 glob2(Char *pathbuf, Char *pathend, Char *pattern, glob_t *pglob,
 520       size_t *limit)
 521 {
 522         struct stat sb;
 523         Char *p, *q;
 524         int anymeta;
 525
 526         /*
 527          * Loop over pattern segments until end of pattern or until
 528          * segment with meta character found.
 529          */
 530         for (anymeta = 0;;) {
 531                 if (*pattern == CHAR_EOS) {             /* End of pattern? */
 532                         *pathend = CHAR_EOS;
 533                         if (g_lstat(pathbuf, &sb, pglob))
 534                                 return(0);
 535
 536                         if (((pglob->gl_flags & GLOB_MARK) &&
 537                             pathend[-1] != CHAR_SEP) && (S_ISDIR(sb.st_mode)
 538                             || (S_ISLNK(sb.st_mode) &&
 539                             (g_stat(pathbuf, &sb, pglob) == 0) &&
 540                             S_ISDIR(sb.st_mode)))) {
 541                                 *pathend++ = CHAR_SEP;
 542                                 *pathend = CHAR_EOS;
 543                         }
 544                         ++pglob->gl_matchc;
 545                         return(globextend(pathbuf, pglob, limit));
 546                 }
 547
 548                 /* Find end of next segment, copy tentatively to pathend. */
 549                 q = pathend;
 550                 p = pattern;
 551                 while (*p != CHAR_EOS && *p != CHAR_SEP) {
 552                         if (ismeta(*p))
 553                                 anymeta = 1;
 554                         *q++ = *p++;
 555                 }
 556
 557                 if (!anymeta) {         /* No expansion, do next segment. */
 558                         pathend = q;
 559                         pattern = p;
 560                         while (*pattern == CHAR_SEP)
 561                                 *pathend++ = *pattern++;
 562                 } else                  /* Need expansion, recurse. */
 563                         return(glob3(pathbuf, pathend, pattern, p, pglob,
 564                             limit));
 565         }
 566         /* NOTREACHED */
 567 }
 568
 569 static int
 570 glob3(Char *pathbuf, Char *pathend, Char *pattern, Char *restpattern,
 571       glob_t *pglob, size_t *limit)
 572 {
 573         struct dirent *dp;
 574         DIR *dirp;
 575         int ret;
 576         char buf[MaxPathLen];
 577
 578         /*
 579          * The readdirfunc declaration can't be prototyped, because it is
 580          * assigned, below, to two functions which are prototyped in glob.h
 581          * and dirent.h as taking pointers to differently typed opaque
 582          * structures.
 583          */
 584         struct dirent *(*readdirfunc)(void *);
 585
 586         *pathend = CHAR_EOS;
 587         errno = 0;
 588
 589         if ((dirp = g_opendir(pathbuf, pglob)) == NULL) {
 590                 /* TODO: don't call for ENOENT or ENOTDIR? */
 591                 if (pglob->gl_errfunc) {
 592                         g_Ctoc(pathbuf, buf);
 593                         if (pglob->gl_errfunc(buf, errno) ||
 594                             pglob->gl_flags & GLOB_ERR)
 595                                 return (GLOB_ABEND);
 596                 }
 597                 return(0);
 598         }
 599
 600         ret = 0;
 601
 602         /* Search directory for matching names. */
 603         if (pglob->gl_flags & GLOB_ALTDIRFUNC)
 604                 readdirfunc = pglob->gl_readdir;
 605         else
 606                 readdirfunc = (struct dirent *(*)(void *))readdir;
 607         while ((dp = (*readdirfunc)(dirp))) {
 608                 u_char *sc;
 609                 Char *dc;
 610
 611                 /* Initial CHAR_DOT must be matched literally. */
 612                 if (dp->d_name[0] == CHAR_DOT && *pattern != CHAR_DOT)
 613                         continue;
 614                 for (sc = (u_char *) dp->d_name, dc = pathend;
 615                      (*dc++ = *sc++) != CHAR_EOS;)
 616                         continue;
 617                 if (!match(pathend, pattern, restpattern)) {
 618                         *pathend = CHAR_EOS;
 619                         continue;
 620                 }
 621                 ret = glob2(pathbuf, --dc, restpattern, pglob, limit);
 622                 if (ret)
 623                         break;
 624         }
 625
 626         if (pglob->gl_flags & GLOB_ALTDIRFUNC)
 627                 (*pglob->gl_closedir)(dirp);
 628         else
 629                 closedir(dirp);
 630         return(ret);
 631 }
 632
 633
 634 /*
 635  * Extend the gl_pathv member of a glob_t structure to accomodate a new item,
 636  * add the new item, and update gl_pathc.
 637  *
 638  * This assumes the BSD realloc, which only copies the block when its size
 639  * crosses a power-of-two boundary; for v7 realloc, this would cause quadratic
 640  * behavior.
 641  *
 642  * Return 0 if new item added, error code if memory couldn't be allocated.
 643  *
 644  * Invariant of the glob_t structure:
 645  *      Either gl_pathc is zero and gl_pathv is NULL; or gl_pathc > 0 and
 646  *      gl_pathv points to (gl_offs + gl_pathc + 1) items.
 647  */
 648 static int
 649 globextend(const Char *path, glob_t *pglob, size_t *limit)
 650 {
 651         char **pathv;
 652         int i;
 653         size_t newsize, len;
 654         char *copy;
 655         const Char *p;
 656
 657         newsize = sizeof(*pathv) * (2 + pglob->gl_pathc + pglob->gl_offs);
 658         pathv = pglob->gl_pathv ?
 659                     realloc(pglob->gl_pathv, newsize) :
 660                     malloc(newsize);
 661         if (pathv == NULL)
 662                 return(GLOB_NOSPACE);
 663
 664         if (pglob->gl_pathv == NULL && pglob->gl_offs > 0) {
 665                 /* first time around -- clear initial gl_offs items */
 666                 pathv += pglob->gl_offs;
 667                 for (i = pglob->gl_offs; --i >= 0; )
 668                         *--pathv = NULL;
 669         }
 670         pglob->gl_pathv = pathv;
 671
 672         for (p = path; *p++;)
 673                 continue;
 674         len = (size_t)(p - path);
 675         *limit += len;
 676         if ((copy = malloc(len)) != NULL) {
 677                 g_Ctoc(path, copy);
 678                 pathv[pglob->gl_offs + pglob->gl_pathc++] = copy;
 679         }
 680         pathv[pglob->gl_offs + pglob->gl_pathc] = NULL;
 681
 682         if ((pglob->gl_flags & GLOB_LIMIT) && (newsize + *limit) >= ARG_MAX) {
 683                 errno = 0;
 684                 return(GLOB_NOSPACE);
 685         }
 686
 687         return(copy == NULL ? GLOB_NOSPACE : 0);
 688 }
 689
 690
 691 /*
 692  * pattern matching function for filenames.  Each occurrence of the *
 693  * pattern causes a recursion level.
 694  */
 695 static int
 696 match(Char *name, Char *pat, Char *patend)
 697 {
 698         int ok, negate_range;
 699         Char c, k;
 700
 701         while (pat < patend) {
 702                 c = *pat++;
 703                 switch (c & M_MASK) {
 704                 case M_ALL:
 705                         if (pat == patend)
 706                                 return(1);
 707                         do
 708                             if (match(name, pat, patend))
 709                                     return(1);
 710                         while (*name++ != CHAR_EOS);
 711                         return(0);
 712                 case M_ONE:
 713                         if (*name++ == CHAR_EOS)
 714                                 return(0);
 715                         break;
 716                 case M_SET:
 717                         ok = 0;
 718                         if ((k = *name++) == CHAR_EOS)
 719                                 return(0);
 720                         if ((negate_range = ((*pat & M_MASK) == M_NOT)) != CHAR_EOS)
 721                                 ++pat;
 722                         while (((c = *pat++) & M_MASK) != M_END)
 723                                 if ((*pat & M_MASK) == M_RNG) {
 724                                         if (c <= k && k <= pat[1])
 725                                                 ok = 1;
 726                                         pat += 2;
 727                                 } else if (c == k)
 728                                         ok = 1;
 729                         if (ok == negate_range)
 730                                 return(0);
 731                         break;
 732                 default:
 733                         if (*name++ != c)
 734                                 return(0);
 735                         break;
 736                 }
 737         }
 738         return(*name == CHAR_EOS);
 739 }
 740
 741 /* Free allocated data belonging to a glob_t structure. */
 742 ROKEN_LIB_FUNCTION void ROKEN_LIB_CALL
 743 globfree(glob_t *pglob)
 744 {
 745         int i;
 746         char **pp;
 747
 748         if (pglob->gl_pathv != NULL) {
 749                 pp = pglob->gl_pathv + pglob->gl_offs;
 750                 for (i = pglob->gl_pathc; i--; ++pp)
 751                         if (*pp)
 752                                 free(*pp);
 753                 free(pglob->gl_pathv);
 754                 pglob->gl_pathv = NULL;
 755         }
 756 }
 757
 758 static DIR *
 759 g_opendir(Char *str, glob_t *pglob)
 760 {
 761         char buf[MaxPathLen];
 762
 763         if (!*str)
 764                 strlcpy(buf, ".", sizeof(buf));
 765         else
 766                 g_Ctoc(str, buf);
 767
 768         if (pglob->gl_flags & GLOB_ALTDIRFUNC)
 769                 return((*pglob->gl_opendir)(buf));
 770
 771         return(opendir(buf));
 772 }
 773
 774 static int
 775 g_lstat(Char *fn, struct stat *sb, glob_t *pglob)
 776 {
 777         char buf[MaxPathLen];
 778
 779         g_Ctoc(fn, buf);
 780         if (pglob->gl_flags & GLOB_ALTDIRFUNC)
 781                 return((*pglob->gl_lstat)(buf, sb));
 782         return(lstat(buf, sb));
 783 }
 784
 785 static int
 786 g_stat(Char *fn, struct stat *sb, glob_t *pglob)
 787 {
 788         char buf[MaxPathLen];
 789
 790         g_Ctoc(fn, buf);
 791         if (pglob->gl_flags & GLOB_ALTDIRFUNC)
 792                 return((*pglob->gl_stat)(buf, sb));
 793         return(stat(buf, sb));
 794 }
 795
 796 static Char *
 797 g_strchr(const Char *str, int ch)
 798 {
 799         do {
 800                 if (*str == ch)
 801                         return (Char *)str;
 802         } while (*str++);
 803         return (NULL);
 804 }
 805
 806 #ifdef notdef
 807 static Char *
 808 g_strcat(Char *dst, const Char *src)
 809 {
 810         Char *sdst = dst;
 811
 812         while (*dst++)
 813                 continue;
 814         --dst;
 815         while((*dst++ = *src++) != CHAR_EOS)
 816             continue;
 817
 818         return (sdst);
 819 }
 820 #endif
 821
 822 static void
 823 g_Ctoc(const Char *str, char *buf)
 824 {
 825         char *dc;
 826
 827         for (dc = buf; (*dc++ = *str++) != CHAR_EOS;)
 828                 continue;
 829 }
 830
 831 #ifdef DEBUG
 832 static void
 833 qprintf(const Char *str, Char *s)
 834 {
 835         Char *p;
 836
 837         printf("%s:\n", str);
 838         for (p = s; *p; p++)
 839                 printf("%c", CHAR(*p));
 840         printf("\n");
 841         for (p = s; *p; p++)
 842                 printf("%c", *p & M_PROTECT ? '"' : ' ');
 843         printf("\n");
 844         for (p = s; *p; p++)
 845                 printf("%c", ismeta(*p) ? '_' : ' ');
 846         printf("\n");
 847 }
 848 #endif