glob.c

它通过提供glibc兼容使得应用程序移植到较小的c 库时相当得容易. 它能够应用到带虚拟存储的Linux和uClinux上.在大多数带MMU部件的平台上为使它更加紧凑,它也能够编译成共享库.uClib

/* Copyright (C) 1991, 1992, 1993, 1994, 1995 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 <stdlib.h>
#include <string.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <dirent.h>
#include <malloc.h>
#include <fnmatch.h>
#include <glob.h>

extern __ptr_t (*__glob_opendir_hook) __P ((const char *directory));
extern void (*__glob_closedir_hook) __P ((__ptr_t stream));
extern const char *(*__glob_readdir_hook) __P ((__ptr_t stream));


static int glob_pattern_p __P ((const char *pattern, int quote));
static int glob_in_dir __P ((const char *pattern, const char *directory,
			     int flags,
			     int (*errfunc) __P ((const char *, int)),
			     glob_t *pglob));
static int prefix_array __P ((const char *prefix, char **array, size_t n,
			      int add_slash));
static int collated_compare __P ((const __ptr_t, const __ptr_t));

/* Do glob searching for PATTERN, placing results in PGLOB.
   The bits defined above may be set in FLAGS.
   If a directory cannot be opened or read and ERRFUNC is not nil,
   it is called with the pathname that caused the error, and the
   `errno' value from the failing call; if it returns non-zero
   `glob' returns GLOB_ABEND; if it returns zero, the error is ignored.
   If memory cannot be allocated for PGLOB, GLOB_NOSPACE is returned.
   Otherwise, `glob' returns zero.  */
int
glob (pattern, flags, errfunc, pglob)
     const char *pattern;
     int flags;
     int (*errfunc) __P ((const char *, int));
     glob_t *pglob;
{
  const char *filename;
  char *dirname;
  size_t dirlen;
  int status;
  int oldcount;

  if (pattern == NULL || pglob == NULL || (flags & ~__GLOB_FLAGS) != 0)
    {
      errno = EINVAL;
      return -1;
    }

  /* Find the filename.  */
  filename = strrchr (pattern, '/');
  if (filename == NULL)
    {
      filename = pattern;
      dirname = (char *) ".";
      dirlen = 0;
    }
  else if (filename == pattern)
    {
      /* "/pattern".  */
      dirname = (char *) "/";
      dirlen = 1;
      ++filename;
    }
  else
    {
      dirlen = filename - pattern;
      dirname = (char *) alloca (dirlen + 1);
      memcpy (dirname, pattern, dirlen);
      dirname[dirlen] = '\0';
      ++filename;
    }

  if (filename[0] == '\0' && dirlen > 1)
    /* "pattern/".  Expand "pattern", appending slashes.  */
    {
      int val = glob (dirname, flags | GLOB_MARK, errfunc, pglob);
      if (val == 0)
	pglob->gl_flags = (pglob->gl_flags & ~GLOB_MARK) | (flags & GLOB_MARK);
      return val;
    }

  if (!(flags & GLOB_APPEND))
    {
      pglob->gl_pathc = 0;
      pglob->gl_pathv = NULL;
    }

  oldcount = pglob->gl_pathc;

  if (glob_pattern_p (dirname, !(flags & GLOB_NOESCAPE)))
    {
      /* The directory name contains metacharacters, so we
	 have to glob for the directory, and then glob for
	 the pattern in each directory found.  */
      glob_t dirs;
      register int i;

      status = glob (dirname,
		     ((flags & (GLOB_ERR | GLOB_NOCHECK | GLOB_NOESCAPE)) |
		      GLOB_NOSORT),
		     errfunc, &dirs);
      if (status != 0)
	return status;

      /* We have successfully globbed the preceding directory name.
	 For each name we found, call glob_in_dir on it and FILENAME,
	 appending the results to PGLOB.  */
      for (i = 0; i < dirs.gl_pathc; ++i)
	{
	  int oldcount;

#ifdef	SHELL
	  {
	    /* Make globbing interruptible in the bash shell. */
	    extern int interrupt_state;

	    if (interrupt_state)
	      {
		globfree (&dirs);
		globfree (&files);
		return GLOB_ABEND;
	      }
	  }
#endif /* SHELL.  */

	  oldcount = pglob->gl_pathc;
	  status = glob_in_dir (filename, dirs.gl_pathv[i],
				(flags | GLOB_APPEND) & ~GLOB_NOCHECK,
				errfunc, pglob);
	  if (status == GLOB_NOMATCH)
	    /* No matches in this directory.  Try the next.  */
	    continue;

	  if (status != 0)
	    {
	      globfree (&dirs);
	      globfree (pglob);
	      return status;
	    }

	  /* Stick the directory on the front of each name.  */
	  if (prefix_array (dirs.gl_pathv[i],
			    &pglob->gl_pathv[oldcount],
			    pglob->gl_pathc - oldcount,
			    flags & GLOB_MARK))
	    {
	      globfree (&dirs);
	      globfree (pglob);
	      return GLOB_NOSPACE;
	    }
	}

      flags |= GLOB_MAGCHAR;

      if (pglob->gl_pathc == oldcount)
      {
	/* No matches.  */
	if (flags & GLOB_NOCHECK)
	{
	    size_t len = strlen (pattern) + 1;
	    char *patcopy = (char *) malloc (len);
	    if (patcopy == NULL)
	      return GLOB_NOSPACE;
	    memcpy (patcopy, pattern, len);

	    pglob->gl_pathv
	      = (char **) realloc (pglob->gl_pathv,
				   (pglob->gl_pathc +
				    ((flags & GLOB_DOOFFS) ?
				     pglob->gl_offs : 0) +
				    1 + 1) *
				   sizeof (char *));
	    if (pglob->gl_pathv == NULL)
	      {
		free (patcopy);
		return GLOB_NOSPACE;
	      }

	    if (flags & GLOB_DOOFFS)
	      while (pglob->gl_pathc < pglob->gl_offs)
		pglob->gl_pathv[pglob->gl_pathc++] = NULL;

	    pglob->gl_pathv[pglob->gl_pathc++] = patcopy;
	    pglob->gl_pathv[pglob->gl_pathc] = NULL;
	    pglob->gl_flags = flags;
	}
	else 
	{
	  return GLOB_NOMATCH;
	}
      }
    }
  else
    {
      status = glob_in_dir (filename, dirname, flags, errfunc, pglob);
      if (status != 0)
	return status;

      if (dirlen > 0)
	{
	  /* Stick the directory on the front of each name.  */
	  if (prefix_array (dirname,
			    &pglob->gl_pathv[oldcount],
			    pglob->gl_pathc - oldcount,
			    flags & GLOB_MARK))
	    {
	      globfree (pglob);
	      return GLOB_NOSPACE;
	    }
	}
    }

  if (flags & GLOB_MARK)
    {
      /* Append slashes to directory names.  glob_in_dir has already
	 allocated the extra character for us.  */
      int i;
      struct stat st;
      for (i = oldcount; i < pglob->gl_pathc; ++i)
	if (lstat (pglob->gl_pathv[i], &st) == 0 &&
	    S_ISDIR (st.st_mode))
	  strcat (pglob->gl_pathv[i], "/");
    }

  if (!(flags & GLOB_NOSORT))
    /* Sort the vector.  */
    qsort ((__ptr_t) &pglob->gl_pathv[oldcount],
	   pglob->gl_pathc - oldcount,
	   sizeof (char *), (__compar_fn_t)collated_compare);

  return 0;
}


/* Free storage allocated in PGLOB by a previous `glob' call.  */
void
globfree (pglob)
     register glob_t *pglob;
{
  if (pglob->gl_pathv != NULL)
    {
      register int i;
      for (i = 0; i < pglob->gl_pathc; ++i)
	if (pglob->gl_pathv[i] != NULL)
	  free ((__ptr_t) pglob->gl_pathv[i]);
      free ((__ptr_t) pglob->gl_pathv);
    }
}


/* Do a collated comparison of A and B.  */
static int
collated_compare (a, b)
     const __ptr_t a;
     const __ptr_t b;
{
  const char *const s1 = *(const char *const *) a;
  const char *const s2 = *(const char *const *) b;

  if (s1 == s2)
    return 0;
  if (s1 == NULL)
    return 1;
  if (s2 == NULL)
    return -1;
  return strcoll (s1, s2);
}


/* Prepend DIRNAME to each of N members of ARRAY, replacing ARRAY's
   elements in place.  Return nonzero if out of memory, zero if successful.
   A slash is inserted between DIRNAME and each elt of ARRAY,
   unless DIRNAME is just "/".  Each old element of ARRAY is freed.
   If ADD_SLASH is non-zero, allocate one character more than
   necessary, so that a slash can be appended later.  */
static int
prefix_array (dirname, array, n, add_slash)
     const char *dirname;
     char **array;
     size_t n;
     int add_slash;
{
  register size_t i;
  size_t dirlen = strlen (dirname);

  if (dirlen == 1 && dirname[0] == '/')
    /* DIRNAME is just "/", so normal prepending would get us "//foo".
       We want "/foo" instead, so don't prepend any chars from DIRNAME.  */
    dirlen = 0;

  for (i = 0; i < n; ++i)
    {
      size_t eltlen = strlen (array[i]) + 1;
      char *new = (char *) malloc (dirlen + 1 + eltlen + (add_slash ? 1 : 0));
      if (new == NULL)
	{
	  while (i > 0)
	    free ((__ptr_t) array[--i]);
	  return 1;
	}

      memcpy (new, dirname, dirlen);
      new[dirlen] = '/';
      memcpy (&new[dirlen + 1], array[i], eltlen);
      free ((__ptr_t) array[i]);
      array[i] = new;
    }

  return 0;
}


/* Return nonzero if PATTERN contains any metacharacters.
   Metacharacters can be quoted with backslashes if QUOTE is nonzero.  */
static int
glob_pattern_p (pattern, quote)
     const char *pattern;
     int quote;
{
  register const char *p;
  int open = 0;

  for (p = pattern; *p != '\0'; ++p)
    switch (*p)
      {
      case '?':
      case '*':
	return 1;

      case '\\':
	if (quote)
	  ++p;
	break;

      case '[':
	open = 1;
	break;

      case ']':
	if (open)
	  return 1;
	break;
      }

  return 0;
}


/* Like `glob', but PATTERN is a final pathname component,
   and matches are searched for in DIRECTORY.
   The GLOB_NOSORT bit in FLAGS is ignored.  No sorting is ever done.
   The GLOB_APPEND flag is assumed to be set (always appends).  */
static int
glob_in_dir (pattern, directory, flags, errfunc, pglob)
     const char *pattern;
     const char *directory;
     int flags;
     int (*errfunc) __P ((const char *, int));
     glob_t *pglob;
{
  __ptr_t stream;

  struct globlink
    {
      struct globlink *next;
      char *name;
    };
  struct globlink *names = NULL;
  size_t nfound = 0;
  int meta;

  stream = (__glob_opendir_hook ? (*__glob_opendir_hook) (directory)
	   : (__ptr_t) opendir (directory));
  if (stream == NULL)
    {
      if ((errfunc != NULL && (*errfunc) (directory, errno)) ||
	  (flags & GLOB_ERR))
	return GLOB_ABORTED;
    }

  meta = glob_pattern_p (pattern, !(flags & GLOB_NOESCAPE));

  if (meta)
    flags |= GLOB_MAGCHAR;

  while (1)
    {
      const char *name;
      size_t len;

      if (__glob_readdir_hook)
	{
	  name = (*__glob_readdir_hook) (stream);
	  if (name == NULL)
	    break;
	  len = 0;
	}
      else
	{
	  struct dirent *d = readdir ((DIR *) stream);
	  if (d == NULL)
	    break;
	  if (! (d->d_ino != 0))
	    continue;
	  name = d->d_name;
#ifdef	HAVE_D_NAMLEN
	  len = d->d_namlen;
#else
	  len = 0;
#endif
	}
		
      if ((!meta && strcmp (pattern, name) == 0)
	  || fnmatch (pattern, name,
		      (!(flags & GLOB_PERIOD) ? FNM_PERIOD : 0) |
		      ((flags & GLOB_NOESCAPE) ? FNM_NOESCAPE : 0)) == 0)
	{
	  struct globlink *new
	    = (struct globlink *) alloca (sizeof (struct globlink));
	  if (len == 0)
	    len = strlen (name);
	  new->name
	    = (char *) malloc (len + ((flags & GLOB_MARK) ? 1 : 0) + 1);
	  if (new->name == NULL)
	    goto memory_error;
	  memcpy ((__ptr_t) new->name, name, len);
	  new->name[len] = '\0';
	  new->next = names;
	  names = new;
	  ++nfound;
	  if (!meta)
	    break;
	}
    }

  if (nfound == 0 && (flags & GLOB_NOCHECK))
    {
      size_t len = strlen (pattern);
      nfound = 1;
      names = (struct globlink *) alloca (sizeof (struct globlink));
      names->next = NULL;
      names->name = (char *) malloc (len + (flags & GLOB_MARK ? 1 : 0) + 1);
      if (names->name == NULL)
	goto memory_error;
      memcpy (names->name, pattern, len);
      names->name[len] = '\0';
    }

  pglob->gl_pathv
    = (char **) realloc (pglob->gl_pathv,
			 (pglob->gl_pathc +
			  ((flags & GLOB_DOOFFS) ? pglob->gl_offs : 0) +
			  nfound + 1) *
			 sizeof (char *));
  if (pglob->gl_pathv == NULL)
    goto memory_error;

  if (flags & GLOB_DOOFFS)
    while (pglob->gl_pathc < pglob->gl_offs)
      pglob->gl_pathv[pglob->gl_pathc++] = NULL;

  for (; names != NULL; names = names->next)
    pglob->gl_pathv[pglob->gl_pathc++] = names->name;
  pglob->gl_pathv[pglob->gl_pathc] = NULL;

  pglob->gl_flags = flags;

  {
    int save = errno;
    if (__glob_closedir_hook)
      (*__glob_closedir_hook) (stream);
    else
      (void) closedir ((DIR *) stream);
    errno = save;
  }
  return nfound == 0 ? GLOB_NOMATCH : 0;

 memory_error:
  {
    int save = errno;
    if (__glob_closedir_hook)
      (*__glob_closedir_hook) (stream);
    else
      (void) closedir ((DIR *) stream);
    errno = save;
  }
  while (names != NULL)
    {
      if (names->name != NULL)
	free ((__ptr_t) names->name);
      names = names->next;
    }
  return GLOB_NOSPACE;
}