New module 'scandir'.

2 files changed, 192 insertions, 2 deletions

diff --git a/lib/dirent.in.h b/lib/dirent.in.h
index 2b1d0a52a2..40824c56b7 100644
--- a/lib/dirent.in.h
+++ b/lib/dirent.in.h
@@ -1,5 +1,5 @@
 /* A GNU-like <dirent.h>.
-   Copyright (C) 2006-2008 Free Software Foundation, Inc.
+   Copyright (C) 2006-2009 Free Software Foundation, Inc.
 
    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -42,7 +42,7 @@ extern DIR * opendir (const char *);
 extern int closedir (DIR *);
 #endif
 
-/* Declare GNU extensions.  */
+/* Declare other POSIX functions.  */
 
 #if @GNULIB_DIRFD@
 # if !@HAVE_DECL_DIRFD@ && !defined dirfd
@@ -58,6 +58,24 @@ extern int dirfd (DIR const *dir);
      dirfd (d))
 #endif
 
+#if @GNULIB_SCANDIR@
+/* Scan the directory DIR, calling FILTER on each directory entry.
+   Entries for which FILTER returns nonzero are individually malloc'd,
+   sorted using qsort with CMP, and collected in a malloc'd array in
+   *NAMELIST.  Returns the number of entries selected, or -1 on error.  */
+# if !@HAVE_SCANDIR@
+extern int scandir (const char *dir, struct dirent ***namelist,
+		    int (*filter) (const struct dirent *),
+		    int (*cmp) (const struct dirent **, const struct dirent **));
+# endif
+#elif defined GNULIB_POSIXCHECK
+# undef scandir
+# define scandir(d,n,f,c) \
+    (GL_LINK_WARNING ("scandir is unportable - " \
+                      "use gnulib module scandir for portability"), \
+     scandir (d, n, f, c))
+#endif
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/lib/scandir.c b/lib/scandir.c
new file mode 100644
index 0000000000..8b34070e86
--- /dev/null
+++ b/lib/scandir.c
@@ -0,0 +1,172 @@
+/* Copyright (C) 1992-1998, 2000, 2002, 2003, 2009 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   This program is free software; you can redistribute it and/or modify it
+   under the terms of the GNU General Public License as published by the
+   Free Software Foundation; either version 2, or (at your option) any
+   later version.
+
+   This program 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 General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software Foundation,
+   Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
+
+#include <config.h>
+
+#include <dirent.h>
+
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#if _LIBC
+# include <bits/libc-lock.h>
+#endif
+
+#if ! defined __builtin_expect && __GNUC__ < 3
+# define __builtin_expect(expr, expected) (expr)
+#endif
+
+#undef select
+
+#if _LIBC
+# ifndef SCANDIR
+#  define SCANDIR scandir
+#  define READDIR __readdir
+#  define DIRENT_TYPE struct dirent
+# endif
+#else
+# define SCANDIR scandir
+# define READDIR readdir
+# define DIRENT_TYPE struct dirent
+# define __opendir opendir
+# define __closedir closedir
+# define __set_errno(val) errno = (val)
+#endif
+
+#ifndef SCANDIR_CANCEL
+# define SCANDIR_CANCEL
+struct scandir_cancel_struct
+{
+  DIR *dp;
+  void *v;
+  size_t cnt;
+};
+
+# if _LIBC
+static void
+cancel_handler (void *arg)
+{
+  struct scandir_cancel_struct *cp = arg;
+  size_t i;
+  void **v = cp->v;
+
+  for (i = 0; i < cp->cnt; ++i)
+    free (v[i]);
+  free (v);
+  (void) __closedir (cp->dp);
+}
+# endif
+#endif
+
+
+int
+SCANDIR (const char *dir,
+	 DIRENT_TYPE ***namelist,
+	 int (*select) (const DIRENT_TYPE *),
+	 int (*cmp) (const DIRENT_TYPE **, const DIRENT_TYPE **))
+{
+  DIR *dp = __opendir (dir);
+  DIRENT_TYPE **v = NULL;
+  size_t vsize = 0;
+  struct scandir_cancel_struct c;
+  DIRENT_TYPE *d;
+  int save;
+
+  if (dp == NULL)
+    return -1;
+
+  save = errno;
+  __set_errno (0);
+
+  c.dp = dp;
+  c.v = NULL;
+  c.cnt = 0;
+#if _LIBC
+  __libc_cleanup_push (cancel_handler, &c);
+#endif
+
+  while ((d = READDIR (dp)) != NULL)
+    {
+      int use_it = select == NULL;
+
+      if (! use_it)
+	{
+	  use_it = select (d);
+	  /* The select function might have changed errno.  It was
+	     zero before and it need to be again to make the latter
+	     tests work.  */
+	  __set_errno (0);
+	}
+
+      if (use_it)
+	{
+	  DIRENT_TYPE *vnew;
+	  size_t dsize;
+
+	  /* Ignore errors from select or readdir */
+	  __set_errno (0);
+
+	  if (__builtin_expect (c.cnt == vsize, 0))
+	    {
+	      DIRENT_TYPE **new;
+	      if (vsize == 0)
+		vsize = 10;
+	      else
+		vsize *= 2;
+	      new = (DIRENT_TYPE **) realloc (v, vsize * sizeof (*v));
+	      if (new == NULL)
+		break;
+	      v = new;
+	      c.v = (void *) v;
+	    }
+
+	  dsize = &d->d_name[_D_ALLOC_NAMLEN (d)] - (char *) d;
+	  vnew = (DIRENT_TYPE *) malloc (dsize);
+	  if (vnew == NULL)
+	    break;
+
+	  v[c.cnt++] = (DIRENT_TYPE *) memcpy (vnew, d, dsize);
+	}
+    }
+
+  if (__builtin_expect (errno, 0) != 0)
+    {
+      save = errno;
+
+      while (c.cnt > 0)
+	free (v[--c.cnt]);
+      free (v);
+      c.cnt = -1;
+    }
+  else
+    {
+      /* Sort the list if we have a comparison function to sort with.  */
+      if (cmp != NULL)
+	qsort (v, c.cnt, sizeof (*v), (int (*) (const void *, const void *)) cmp);
+
+      *namelist = v;
+    }
+
+#if _LIBC
+  __libc_cleanup_pop (0);
+#endif
+
+  (void) __closedir (dp);
+  __set_errno (save);
+
+  return c.cnt;
+}