* readdir.m4: Revivify this file.

We need it to work around a bug on Darwin 0.7.x.

2 files changed, 144 insertions, 0 deletions

diff --git a/m4/ChangeLog b/m4/ChangeLog
index eefb7ca78..17aadd5d5 100644
--- a/m4/ChangeLog
+++ b/m4/ChangeLog
@@ -1,3 +1,8 @@
+2006-09-28  Jim Meyering  <jim@meyering.net>
+
+	* readdir.m4: Revivify this file.
+	We need it to work around a bug on Darwin 0.7.x.
+
 2006-09-01  Paul Eggert  <eggert@cs.ucla.edu>
 
 	* .cvsignore: Add fcntl_h.m4, getloadavg.m4, inttypes-h.m4,
diff --git a/m4/readdir.m4 b/m4/readdir.m4
new file mode 100644
index 000000000..7783ef020
--- /dev/null
+++ b/m4/readdir.m4
@@ -0,0 +1,139 @@
+#serial 8
+
+# Copyright (C) 1997, 1999, 2000, 2001, 2002, 2003 Free Software
+# Foundation, Inc.
+#
+# This file is free software; the Free Software Foundation
+# gives unlimited permission to copy and/or distribute it,
+# with or without modifications, as long as this notice is preserved.
+
+dnl SunOS's readdir is broken in such a way that rm.c has to add extra code
+dnl to test whether a NULL return value really means there are no more files
+dnl in the directory.
+dnl
+dnl And the rm from coreutils-5.0 exposes a similar problem when there
+dnl are 338 or more files in a directory on a Darwin-6.5 system
+dnl
+dnl Detect the problem by creating a directory containing 500 files (254 not
+dnl counting . and .. is the minimum for SunOS, 338 for Darwin) and see
+dnl if a loop doing `readdir; unlink' removes all of them.
+dnl
+dnl Define HAVE_WORKING_READDIR if readdir does *not* have this problem.
+
+dnl Written by Jim Meyering.
+
+AC_DEFUN([GL_FUNC_READDIR],
+[dnl
+AC_REQUIRE([AC_HEADER_DIRENT])
+AC_CACHE_CHECK([for working readdir], gl_cv_func_working_readdir,
+  [dnl
+  # Arrange for deletion of the temporary directory this test creates, in
+  # case the test itself fails to delete everything -- as happens on Sunos.
+  ac_clean_files="$ac_clean_files conf-dir"
+
+  AC_TRY_RUN(
+[#   include <stdio.h>
+#   include <sys/types.h>
+#   include <string.h>
+
+#   ifdef HAVE_DIRENT_H
+#    include <dirent.h>
+#    define NLENGTH(direct) (strlen((direct)->d_name))
+#   else /* not HAVE_DIRENT_H */
+#    define dirent direct
+#    define NLENGTH(direct) ((direct)->d_namlen)
+#    ifdef HAVE_SYS_NDIR_H
+#     include <sys/ndir.h>
+#    endif /* HAVE_SYS_NDIR_H */
+#    ifdef HAVE_SYS_DIR_H
+#     include <sys/dir.h>
+#    endif /* HAVE_SYS_DIR_H */
+#    ifdef HAVE_NDIR_H
+#     include <ndir.h>
+#    endif /* HAVE_NDIR_H */
+#   endif /* HAVE_DIRENT_H */
+
+#   define DOT_OR_DOTDOT(Basename) \
+     (Basename[0] == '.' && (Basename[1] == '\0' \
+			     || (Basename[1] == '.' && Basename[2] == '\0')))
+
+/* Don't try to use replacement mkdir; it wouldn't resolve at link time.  */
+#   undef mkdir
+
+    static void
+    create_N_file_dir (const char *dir, size_t n_files)
+    {
+      unsigned int i;
+
+      if (mkdir (dir, 0700))
+	abort ();
+      if (chdir (dir))
+	abort ();
+
+      for (i = 0; i < n_files; i++)
+	{
+	  char file_name[4];
+	  FILE *out;
+
+	  sprintf (file_name, "%03d", i);
+	  out = fopen (file_name, "w");
+	  if (!out)
+	    abort ();
+	  if (fclose (out) == EOF)
+	    abort ();
+	}
+
+      if (chdir (".."))
+	abort ();
+    }
+
+    static void
+    remove_dir (const char *dir)
+    {
+      DIR *dirp;
+
+      if (chdir (dir))
+	abort ();
+
+      dirp = opendir (".");
+      if (dirp == NULL)
+	abort ();
+
+      while (1)
+	{
+	  struct dirent *dp = readdir (dirp);
+	  if (dp == NULL)
+	    break;
+
+	  if (DOT_OR_DOTDOT (dp->d_name))
+	    continue;
+
+	  if (unlink (dp->d_name))
+	    abort ();
+	}
+      closedir (dirp);
+
+      if (chdir (".."))
+	abort ();
+
+      if (rmdir (dir))
+	exit (1);
+    }
+
+    int
+    main ()
+    {
+      const char *dir = "conf-dir";
+      create_N_file_dir (dir, 500);
+      remove_dir (dir);
+      exit (0);
+    }],
+  gl_cv_func_working_readdir=yes,
+  gl_cv_func_working_readdir=no,
+  gl_cv_func_working_readdir=no)])
+
+  if test $gl_cv_func_working_readdir = yes; then
+    AC_DEFINE(HAVE_WORKING_READDIR, 1,
+      [Define if readdir is found to work properly in some unusual cases. ])
+  fi
+])