gnu/usr.bin/tar/fnmatch.c

/* Copyright (C) 1991, 1992 Free Software Foundation, Inc.

This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.

This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
Library General Public License for more details.

You should have received a copy of the GNU Library General Public
License along with this library; see the file COPYING.LIB.  If
not, write to the Free Software Foundation, Inc., 675 Mass Ave,
Cambridge, MA 02139, USA.  */

#include <errno.h>
#include <fnmatch.h>

#if !defined(__GNU_LIBRARY__) && !defined(STDC_HEADERS)
extern int errno;
#endif

/* Match STRING against the filename pattern PATTERN, returning zero if
   it matches, nonzero if not.  */
int
fnmatch (pattern, string, flags)
     const char *pattern;
     const char *string;
     int flags;
{
  register const char *p = pattern, *n = string;
  register char c;

  if ((flags & ~__FNM_FLAGS) != 0)
    {
      errno = EINVAL;
      return -1;
    }

  while ((c = *p++) != '\0')
    {
      switch (c)
        {
        case '?':
          if (*n == '\0')
            return FNM_NOMATCH;
          else if ((flags & FNM_PATHNAME) && *n == '/')
            return FNM_NOMATCH;
          else if ((flags & FNM_PERIOD) && *n == '.' &&
                   (n == string || ((flags & FNM_PATHNAME) && n[-1] == '/')))
            return FNM_NOMATCH;
          break;

        case '\\':
          if (!(flags & FNM_NOESCAPE))
            c = *p++;
          if (*n != c)
            return FNM_NOMATCH;
          break;

        case '*':
          if ((flags & FNM_PERIOD) && *n == '.' &&
              (n == string || ((flags & FNM_PATHNAME) && n[-1] == '/')))
            return FNM_NOMATCH;

          for (c = *p++; c == '?' || c == '*'; c = *p++, ++n)
            if (((flags & FNM_PATHNAME) && *n == '/') ||
                (c == '?' && *n == '\0'))
              return FNM_NOMATCH;

          if (c == '\0')
            return 0;

          {
            char c1 = (!(flags & FNM_NOESCAPE) && c == '\\') ? *p : c;
            for (--p; *n != '\0'; ++n)
              if ((c == '[' || *n == c1) &&
                  fnmatch (p, n, flags & ~FNM_PERIOD) == 0)
                return 0;
            return FNM_NOMATCH;
          }

        case '[':
          {
            /* Nonzero if the sense of the character class is inverted.  */
            register int not;

            if (*n == '\0')
              return FNM_NOMATCH;

            if ((flags & FNM_PERIOD) && *n == '.' &&
                (n == string || ((flags & FNM_PATHNAME) && n[-1] == '/')))
              return FNM_NOMATCH;

            not = (*p == '!' || *p == '^');
            if (not)
              ++p;

            c = *p++;
            for (;;)
              {
                register char cstart = c, cend = c;

                if (!(flags & FNM_NOESCAPE) && c == '\\')
                  cstart = cend = *p++;

                if (c == '\0')
                  /* [ (unterminated) loses.  */
                  return FNM_NOMATCH;

                c = *p++;

                if ((flags & FNM_PATHNAME) && c == '/')
                  /* [/] can never match.  */
                  return FNM_NOMATCH;

                if (c == '-' && *p != ']')
                  {
                    cend = *p++;
                    if (!(flags & FNM_NOESCAPE) && cend == '\\')
                      cend = *p++;
                    if (cend == '\0')
                      return FNM_NOMATCH;
                    c = *p++;
                  }

                if (*n >= cstart && *n <= cend)
                  goto matched;

                if (c == ']')
                  break;
              }
            if (!not)
              return FNM_NOMATCH;
            break;

          matched:;
            /* Skip the rest of the [...] that already matched.  */
            while (c != ']')
              {
                if (c == '\0')
                  /* [... (unterminated) loses.  */
                  return FNM_NOMATCH;

                c = *p++;
                if (!(flags & FNM_NOESCAPE) && c == '\\')
                  /* 1003.2d11 is unclear if this is right.  %%% */
                  ++p;
              }
            if (not)
              return FNM_NOMATCH;
          }
          break;

        default:
          if (c != *n)
            return FNM_NOMATCH;
        }

      ++n;
    }

  if (*n == '\0')
    return 0;

  if ((flags & FNM_LEADING_DIR) && *n == '/')
    /* The FNM_LEADING_DIR flag says that "foo*" matches "foobar/frobozz".  */
    return 0;

  return FNM_NOMATCH;
}