Imported Upstream version 1.5

[debian/gzip] / lib / savedir.c

diff --git a/lib/savedir.c b/lib/savedir.c
new file mode 100644 (file)
index 0000000..95dc6c6
--- /dev/null
+++ b/lib/savedir.c
@@ -0,0 +1,145 @@
+/* savedir.c -- save the list of files in a directory in a string
+
+   Copyright (C) 1990, 1997-2001, 2003-2006, 2009-2012 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
+   the Free Software Foundation; either version 3 of the License, 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, see <http://www.gnu.org/licenses/>.  */
+
+/* Written by David MacKenzie <djm@gnu.ai.mit.edu>. */
+
+#include <config.h>
+
+#include "savedir.h"
+
+#include <sys/types.h>
+
+#include <errno.h>
+
+#include "dirent--.h"
+#ifndef _D_EXACT_NAMLEN
+# define _D_EXACT_NAMLEN(dp)    strlen ((dp)->d_name)
+#endif
+
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "xalloc.h"
+
+#ifndef NAME_SIZE_DEFAULT
+# define NAME_SIZE_DEFAULT 512
+#endif
+
+/* Return a freshly allocated string containing the file names
+   in directory DIRP, separated by '\0' characters;
+   the end is marked by two '\0' characters in a row.
+   Return NULL (setting errno) if DIRP cannot be read.
+   If DIRP is NULL, return NULL without affecting errno.  */
+
+char *
+streamsavedir (DIR *dirp)
+{
+  char *name_space;
+  size_t allocated = NAME_SIZE_DEFAULT;
+  size_t used = 0;
+  int save_errno;
+
+  if (dirp == NULL)
+    return NULL;
+
+  name_space = xmalloc (allocated);
+
+  for (;;)
+    {
+      struct dirent const *dp;
+      char const *entry;
+
+      errno = 0;
+      dp = readdir (dirp);
+      if (! dp)
+        break;
+
+      /* Skip "", ".", and "..".  "" is returned by at least one buggy
+         implementation: Solaris 2.4 readdir on NFS file systems.  */
+      entry = dp->d_name;
+      if (entry[entry[0] != '.' ? 0 : entry[1] != '.' ? 1 : 2] != '\0')
+        {
+          size_t entry_size = _D_EXACT_NAMLEN (dp) + 1;
+          if (used + entry_size < used)
+            xalloc_die ();
+          if (allocated <= used + entry_size)
+            {
+              do
+                {
+                  if (2 * allocated < allocated)
+                    xalloc_die ();
+                  allocated *= 2;
+                }
+              while (allocated <= used + entry_size);
+
+              name_space = xrealloc (name_space, allocated);
+            }
+          memcpy (name_space + used, entry, entry_size);
+          used += entry_size;
+        }
+    }
+  name_space[used] = '\0';
+  save_errno = errno;
+  if (save_errno != 0)
+    {
+      free (name_space);
+      errno = save_errno;
+      return NULL;
+    }
+  return name_space;
+}
+
+/* Like streamsavedir (DIRP), except also close DIRP.  */
+
+static char *
+savedirstream (DIR *dirp)
+{
+  char *name_space = streamsavedir (dirp);
+  if (dirp && closedir (dirp) != 0)
+    {
+      int save_errno = errno;
+      free (name_space);
+      errno = save_errno;
+      return NULL;
+    }
+  return name_space;
+}
+
+/* Return a freshly allocated string containing the file names
+   in directory DIR, separated by '\0' characters;
+   the end is marked by two '\0' characters in a row.
+   Return NULL (setting errno) if DIR cannot be opened, read, or closed.  */
+
+char *
+savedir (char const *dir)
+{
+  return savedirstream (opendir (dir));
+}
+
+/* Return a freshly allocated string containing the file names
+   in directory FD, separated by '\0' characters;
+   the end is marked by two '\0' characters in a row.
+   Return NULL (setting errno) if FD cannot be read or closed.  */
+
+/* deprecated */
+char *
+fdsavedir (int fd)
+{
+  return savedirstream (fdopendir (fd));
+}