* cygerrno.h (geterrno_from_win_error): Change declaration to default to using

GetLastError and EACCESS.
* cygwin.din: Export readdir_r.
* include/cygwin/version.h: Bump API version number to 138.
* syscalls.cc (readdir_worker): New function, renamed from old readdir()
function.
(readdir): Use readdir_worker.
(readdir_r): New function.
* fhandler.h (fhandler_base::readdir): Accommodate second argument indicating
dirent buffer.
(fhandler_disk_file::readdir): Ditto.
(fhandler_cygdrive::readdir): Ditto.
(fhandler_proc::readdir): Ditto.
(fhandler_netdrive::readdir): Ditto.
(fhandler_registry::readdir): Ditto.
(fhandler_process::readdir): Ditto.
* fhandler.cc (fhandler_base::readdir): Ditto.
* fhandler_disk_file.cc (fhandler_disk_file::readdir): Ditto.
* fhandler_cygdrive.cc (fhandler_cygdrive::readdir): Ditto.
* fhandler_proc.cc (fhandler_proc::readdir): Ditto.
* fhandler_netdrive.cc (fhandler_netdrive::readdir): Ditto.
* fhandler_registry.cc (fhandler_registry::readdir): Ditto.
* fhandler_process.cc (fhandler_process::readdir): Ditto.

13 files changed, 173 insertions, 120 deletions

diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog
index e0e4c3cf5..691990907 100644
--- a/winsup/cygwin/ChangeLog
+++ b/winsup/cygwin/ChangeLog
@@ -1,3 +1,29 @@
+2005-08-20  Christopher Faylor  <cgf@timesys.com>
+
+	* cygerrno.h (geterrno_from_win_error): Change declaration to default
+	to using GetLastError and EACCESS.
+	* cygwin.din: Export readdir_r.
+	* include/cygwin/version.h: Bump API version number to 138.
+	* syscalls.cc (readdir_worker): New function, renamed from old
+	readdir() function.
+	(readdir): Use readdir_worker.
+	(readdir_r): New function.
+	* fhandler.h (fhandler_base::readdir): Accommodate second argument
+	indicating dirent buffer.
+	(fhandler_disk_file::readdir): Ditto.
+	(fhandler_cygdrive::readdir): Ditto.
+	(fhandler_proc::readdir): Ditto.
+	(fhandler_netdrive::readdir): Ditto.
+	(fhandler_registry::readdir): Ditto.
+	(fhandler_process::readdir): Ditto.
+	* fhandler.cc (fhandler_base::readdir): Ditto.
+	* fhandler_disk_file.cc (fhandler_disk_file::readdir): Ditto.
+	* fhandler_cygdrive.cc (fhandler_cygdrive::readdir): Ditto.
+	* fhandler_proc.cc (fhandler_proc::readdir): Ditto.
+	* fhandler_netdrive.cc (fhandler_netdrive::readdir): Ditto.
+	* fhandler_registry.cc (fhandler_registry::readdir): Ditto.
+	* fhandler_process.cc (fhandler_process::readdir): Ditto.
+
 2005-08-19  Christopher Faylor  <cgf@timesys.com>
 
 	* fhandler.h (dirent_states): Add dirent_saw_proc.
diff --git a/winsup/cygwin/cygerrno.h b/winsup/cygwin/cygerrno.h
index 48528f520..e3b1011ba 100644
--- a/winsup/cygwin/cygerrno.h
+++ b/winsup/cygwin/cygerrno.h
@@ -14,7 +14,7 @@ details. */
 
 void __stdcall seterrno_from_win_error (const char *file, int line, DWORD code) __attribute__ ((regparm(3)));
 void __stdcall seterrno (const char *, int line) __attribute__ ((regparm(2)));
-int __stdcall geterrno_from_win_error (DWORD code, int deferrno) __attribute__ ((regparm(2)));
+int __stdcall geterrno_from_win_error (DWORD code = GetLastError (), int deferrno = 13 /*EACCESS*/) __attribute__ ((regparm(2)));
 
 #define __seterrno() seterrno (__FILE__, __LINE__)
 #define __seterrno_from_win_error(val) seterrno_from_win_error (__FILE__, __LINE__, val)
diff --git a/winsup/cygwin/cygwin.din b/winsup/cygwin/cygwin.din
index da8e055c3..e8a98c4f8 100644
--- a/winsup/cygwin/cygwin.din
+++ b/winsup/cygwin/cygwin.din
@@ -1120,6 +1120,7 @@ read SIGFE
 _read = read SIGFE
 readdir SIGFE
 _readdir = readdir SIGFE
+readdir_r = readdir SIGFE
 readlink SIGFE
 _readlink = readlink SIGFE
 readv SIGFE
diff --git a/winsup/cygwin/dir.cc b/winsup/cygwin/dir.cc
index 894691d8f..ca9ff5979 100644
--- a/winsup/cygwin/dir.cc
+++ b/winsup/cygwin/dir.cc
@@ -65,53 +65,51 @@ opendir (const char *name)
   return res;
 }
 
-/* readdir: POSIX 5.1.2.1 */
-extern "C" struct dirent *
-readdir (DIR *dir)
+int
+readdir_worker (DIR *dir, dirent *de)
 {
   myfault efault;
-  if (efault.faulted (EFAULT))
-    return NULL;
+  if (efault.faulted ())
+    return EFAULT;
 
   if (dir->__d_cookie != __DIRENT_COOKIE)
     {
-      set_errno (EBADF);
       syscall_printf ("%p = readdir (%p)", NULL, dir);
-      return NULL;
+      return EBADF;
     }
 
-  dirent *res = ((fhandler_base *) dir->__fh)->readdir (dir);
+  int res = ((fhandler_base *) dir->__fh)->readdir (dir, de);
 
-  if (!res)
+  if (res)
     {
       if (!(dir->__flags & dirent_saw_dot))
 	{
-	  res = dir->__d_dirent;
-	  strcpy (res->d_name, ".");
+	  strcpy (de->d_name, ".");
 	  dir->__flags |= dirent_saw_dot;
 	  dir->__d_position++;
+	  res = 0;
 	}
       else if (!(dir->__flags & dirent_saw_dot_dot))
 	{
-	  res = dir->__d_dirent;
-	  strcpy (res->d_name, "..");
+	  strcpy (de->d_name, "..");
 	  dir->__flags |= dirent_saw_dot_dot;
 	  dir->__d_position++;
+	  res = 0;
 	}
     }
 
-  if (res)
+  if (!res)
     {
       /* Compute d_ino by combining filename hash with the directory hash
 	 (which was stored in dir->__d_dirhash when opendir was called). */
-      if (res->d_name[0] == '.')
+      if (de->d_name[0] == '.')
 	{
-	  if (res->d_name[1] == '\0')
+	  if (de->d_name[1] == '\0')
 	    {
-	      dir->__d_dirent->d_ino = dir->__d_dirhash;
+	      de->d_ino = dir->__d_dirhash;
 	      dir->__flags |= dirent_saw_dot;
 	    }
-	  else if (res->d_name[1] != '.' || res->d_name[2] != '\0')
+	  else if (de->d_name[1] != '.' || de->d_name[2] != '\0')
 	    goto hashit;
 	  else
 	    {
@@ -122,11 +120,11 @@ readdir (DIR *dir)
 		goto hashit;
 	      *p = '\0';
 	      if (!(p = strrchr (up, '\\')))
-		dir->__d_dirent->d_ino = hash_path_name (0, ".");
+		de->d_ino = hash_path_name (0, ".");
 	      else
 		{
 		  *p = '\0';
-		  dir->__d_dirent->d_ino = hash_path_name (0, up);
+		  de->d_ino = hash_path_name (0, up);
 		}
 	    }
 	}
@@ -134,9 +132,36 @@ readdir (DIR *dir)
 	{
       hashit:
 	  __ino64_t dino = hash_path_name (dir->__d_dirhash, "\\");
-	  dir->__d_dirent->d_ino = hash_path_name (dino, res->d_name);
+	  de->d_ino = hash_path_name (dino, de->d_name);
 	}
-      res->__ino32 = dir->__d_dirent->d_ino;	// for legacy applications
+      de->__ino32 = de->d_ino;	// for legacy applications
+    }
+  return res;
+}
+
+/* readdir: POSIX 5.1.2.1 */
+extern "C" struct dirent *
+readdir (DIR *dir)
+{
+  int res = readdir_worker (dir, dir->__d_dirent);
+  if (res == 0)
+    return dir->__d_dirent;
+  if (res != ENMFILE)
+    set_errno (res);
+  return NULL;
+}
+
+extern "C" int
+readdir_r (DIR *dir, dirent *de, dirent **ode)
+{
+  int res = readdir_worker (dir, de);
+  if (!res)
+    *ode = de;
+  else
+    {
+      *ode = NULL;
+      if (res != ENMFILE)
+	res = 0;
     }
   return res;
 }
diff --git a/winsup/cygwin/fhandler.cc b/winsup/cygwin/fhandler.cc
index 60ea7a62a..63ca99b4a 100644
--- a/winsup/cygwin/fhandler.cc
+++ b/winsup/cygwin/fhandler.cc
@@ -1538,11 +1538,10 @@ fhandler_base::opendir ()
   return NULL;
 }
 
-struct dirent *
-fhandler_base::readdir (DIR *)
+int
+fhandler_base::readdir (DIR *, dirent *)
 {
-  set_errno (ENOTDIR);
-  return NULL;
+  return ENOTDIR;
 }
 
 _off64_t
diff --git a/winsup/cygwin/fhandler.h b/winsup/cygwin/fhandler.h
index 1728c1a39..f371ee0ce 100644
--- a/winsup/cygwin/fhandler.h
+++ b/winsup/cygwin/fhandler.h
@@ -354,7 +354,7 @@ class fhandler_base
   virtual int mkdir (mode_t mode);
   virtual int rmdir ();
   virtual DIR *opendir ();
-  virtual dirent *readdir (DIR *);
+  virtual int readdir (DIR *, dirent *) __attribute__ ((regparm (3)));
   virtual _off64_t telldir (DIR *);
   virtual void seekdir (DIR *, _off64_t);
   virtual void rewinddir (DIR *);
@@ -674,7 +674,7 @@ class fhandler_disk_file: public fhandler_base
   int mkdir (mode_t mode);
   int rmdir ();
   DIR *opendir ();
-  struct dirent *readdir (DIR *);
+  int readdir (DIR *, dirent *) __attribute__ ((regparm (3)));
   _off64_t telldir (DIR *);
   void seekdir (DIR *, _off64_t);
   void rewinddir (DIR *);
@@ -692,7 +692,7 @@ class fhandler_cygdrive: public fhandler_disk_file
  public:
   fhandler_cygdrive ();
   DIR *opendir ();
-  struct dirent *readdir (DIR *);
+  int readdir (DIR *, dirent *) __attribute__ ((regparm (3)));
   void rewinddir (DIR *);
   int closedir (DIR *);
   int __stdcall fstat (struct __stat64 *buf) __attribute__ ((regparm (2)));
@@ -1202,7 +1202,7 @@ class fhandler_proc: public fhandler_virtual
  public:
   fhandler_proc ();
   int exists();
-  struct dirent *readdir (DIR *);
+  int readdir (DIR *, dirent *) __attribute__ ((regparm (3)));
   static DWORD get_proc_fhandler(const char *path);
 
   int open (int flags, mode_t mode = 0);
@@ -1215,7 +1215,7 @@ class fhandler_netdrive: public fhandler_virtual
  public:
   fhandler_netdrive ();
   int exists();
-  struct dirent *readdir (DIR *);
+  int readdir (DIR *, dirent *) __attribute__ ((regparm (3)));
   void seekdir (DIR *, _off64_t);
   void rewinddir (DIR *);
   int closedir (DIR *);
@@ -1230,7 +1230,7 @@ class fhandler_registry: public fhandler_proc
  public:
   fhandler_registry ();
   int exists();
-  struct dirent *readdir (DIR *);
+  int readdir (DIR *, dirent *) __attribute__ ((regparm (3)));
   _off64_t telldir (DIR *);
   void seekdir (DIR *, _off64_t);
   void rewinddir (DIR *);
@@ -1250,7 +1250,7 @@ class fhandler_process: public fhandler_proc
   fhandler_process ();
   int exists();
   DIR *opendir ();
-  struct dirent *readdir (DIR *);
+  int readdir (DIR *, dirent *) __attribute__ ((regparm (3)));
   int open (int flags, mode_t mode = 0);
   int __stdcall fstat (struct __stat64 *buf) __attribute__ ((regparm (2)));
   bool fill_filebuf ();
diff --git a/winsup/cygwin/fhandler_disk_file.cc b/winsup/cygwin/fhandler_disk_file.cc
index 5c8eac9d2..f26c65dd8 100644
--- a/winsup/cygwin/fhandler_disk_file.cc
+++ b/winsup/cygwin/fhandler_disk_file.cc
@@ -1348,27 +1348,29 @@ free_dir:
   return res;
 }
 
-struct dirent *
-fhandler_disk_file::readdir (DIR *dir)
+int
+fhandler_disk_file::readdir (DIR *dir, dirent *de)
 {
   WIN32_FIND_DATA buf;
   HANDLE handle;
-  struct dirent *res = NULL;
+  int res;
 
-  if (dir->__handle == INVALID_HANDLE_VALUE
-      && dir->__d_position == 0)
+  if (dir->__handle == INVALID_HANDLE_VALUE && dir->__d_position == 0)
     {
       handle = FindFirstFileA (dir->__d_dirname, &buf);
       DWORD lasterr = GetLastError ();
       dir->__handle = handle;
       if (handle == INVALID_HANDLE_VALUE && (lasterr != ERROR_NO_MORE_FILES))
 	{
-	  seterrno_from_win_error (__FILE__, __LINE__, lasterr);
-	  return res;
+	  res = geterrno_from_win_error ();
+	  goto out;
 	}
     }
   else if (dir->__handle == INVALID_HANDLE_VALUE)
-    return res;
+    {
+      res = EBADF;
+      goto out;
+    }
   else if (!FindNextFileA (dir->__handle, &buf))
     {
       bool added = false;
@@ -1396,15 +1398,10 @@ fhandler_disk_file::readdir (DIR *dir)
 	buf.dwFileAttributes = 0;
       else
 	{
-	  DWORD lasterr = GetLastError ();
+	  res = geterrno_from_win_error ();
 	  FindClose (dir->__handle);
 	  dir->__handle = INVALID_HANDLE_VALUE;
-	  /* POSIX says you shouldn't set errno when readdir can't
-	     find any more files; so, if another error we leave it set. */
-	  if (lasterr != ERROR_NO_MORE_FILES)
-	      seterrno_from_win_error (__FILE__, __LINE__, lasterr);
-	  syscall_printf ("%p = readdir (%p)", res, dir);
-	  return res;
+	  goto out;
 	}
     }
 
@@ -1427,25 +1424,25 @@ fhandler_disk_file::readdir (DIR *dir)
 
   /* We get here if `buf' contains valid data.  */
   if (pc.isencoded ())
-    fnunmunge (dir->__d_dirent->d_name, buf.cFileName);
+    fnunmunge (de->d_name, buf.cFileName);
   else
-    strcpy (dir->__d_dirent->d_name, buf.cFileName);
+    strcpy (de->d_name, buf.cFileName);
   if (dir->__flags && dirent_isroot)
     {
-      if (strcasematch (dir->__d_dirent->d_name, "dev"))
+      if (strcasematch (de->d_name, "dev"))
 	dir->__flags |= dirent_saw_dev;
-      else if (strcasematch (dir->__d_dirent->d_name, "proc"))
+      else if (strcasematch (de->d_name, "proc"))
 	dir->__flags |= dirent_saw_proc;
-      if (strlen (dir->__d_dirent->d_name) == mount_table->cygdrive_len - 2
-	  && strncasematch (dir->__d_dirent->d_name, mount_table->cygdrive + 1,
+      if (strlen (de->d_name) == mount_table->cygdrive_len - 2
+	  && strncasematch (de->d_name, mount_table->cygdrive + 1,
 			    mount_table->cygdrive_len - 2))
 	dir->__flags |= dirent_saw_cygdrive;
     }
 
   dir->__d_position++;
-  res = dir->__d_dirent;
-  syscall_printf ("%p = readdir (%p) (%s)", &dir->__d_dirent, dir,
-		  buf.cFileName);
+  res = 0;
+out:
+  syscall_printf ("%d = readdir (%p) (%s)", dir, &de, de->d_name);
   return res;
 }
 
@@ -1526,24 +1523,23 @@ fhandler_cygdrive::opendir ()
   return dir;
 }
 
-struct dirent *
-fhandler_cygdrive::readdir (DIR *dir)
+int
+fhandler_cygdrive::readdir (DIR *dir, dirent *de)
 {
   if (!pdrive || !*pdrive)
-    return NULL;
+    return ENMFILE;
   if (GetFileAttributes (pdrive) == INVALID_FILE_ATTRIBUTES)
     {
       pdrive = strchr (pdrive, '\0') + 1;
-      return readdir (dir);
+      return readdir (dir, de);
     }
 
-  *dir->__d_dirent->d_name = cyg_tolower (*pdrive);
-  dir->__d_dirent->d_name[1] = '\0';
+  *de->d_name = cyg_tolower (*pdrive);
+  de->d_name[1] = '\0';
   dir->__d_position++;
   pdrive = strchr (pdrive, '\0') + 1;
-  syscall_printf ("%p = readdir (%p) (%s)", &dir->__d_dirent, dir,
-		  dir->__d_dirent->d_name);
-  return dir->__d_dirent;
+  syscall_printf ("%p = readdir (%p) (%s)", &de, dir, de->d_name);
+  return 0;
 }
 
 void
diff --git a/winsup/cygwin/fhandler_netdrive.cc b/winsup/cygwin/fhandler_netdrive.cc
index 81064ec65..4665d2893 100644
--- a/winsup/cygwin/fhandler_netdrive.cc
+++ b/winsup/cygwin/fhandler_netdrive.cc
@@ -147,12 +147,13 @@ fhandler_netdrive::fstat (struct __stat64 *buf)
   return 0;
 }
 
-struct dirent *
-fhandler_netdrive::readdir (DIR *dir)
+int
+fhandler_netdrive::readdir (DIR *dir, dirent *de)
 {
   DWORD size;
   NETRESOURCE *nro;
   DWORD ret;
+  int res;
 
   if (!dir->__d_position)
     {
@@ -167,8 +168,8 @@ fhandler_netdrive::readdir (DIR *dir)
 	  size = MAX_COMPUTERNAME_LENGTH + 1;
 	  if (!GetComputerName (namebuf + 2, &size))
 	    {
-	      __seterrno ();
-	      return NULL;
+	      res = geterrno_from_win_error ();
+	      goto out;
 	    }
 	}
       else
@@ -189,24 +190,26 @@ fhandler_netdrive::readdir (DIR *dir)
 				    &nr, &dir->__handle, 0, "WNetOpenEnum");
       if (ret != NO_ERROR)
 	{
-	  __seterrno_from_win_error (ret);
 	  dir->__handle = INVALID_HANDLE_VALUE;
-	  return NULL;
+	  res = geterrno_from_win_error (ret);
+	  goto out;
 	}
     }
   ret = create_thread_and_wait (GET_RESOURCE_ENUM, dir->__handle,
 				nro = (LPNETRESOURCE) alloca (16384),
 				16384, "WnetEnumResource");
   if (ret != NO_ERROR)
+    res = geterrno_from_win_error (ret);
+  else
     {
-      if (ret != ERROR_NO_MORE_ITEMS)
-	__seterrno_from_win_error (ret);
-      return NULL;
+      dir->__d_position++;
+      char *bs = strrchr (nro->lpRemoteName, '\\');
+      strcpy (de->d_name, bs ? bs + 1 : nro->lpRemoteName);
+      res = 0;
     }
-  dir->__d_position++;
-  char *bs = strrchr (nro->lpRemoteName, '\\');
-  strcpy (dir->__d_dirent->d_name, bs ? bs + 1 : nro->lpRemoteName);
-  return dir->__d_dirent;
+out:
+  syscall_printf ("%d = readdir (%p, %p)", res, dir, de);
+  return res;
 }
 
 void
@@ -216,7 +219,7 @@ fhandler_netdrive::seekdir (DIR *dir, _off64_t pos)
   if (pos < 0)
     return;
   while (dir->__d_position < pos)
-    if (!readdir (dir))
+    if (!readdir (dir, dir->__d_dirent))
       break;
 }
 
diff --git a/winsup/cygwin/fhandler_proc.cc b/winsup/cygwin/fhandler_proc.cc
index 07ae13e0c..74b25f2f6 100644
--- a/winsup/cygwin/fhandler_proc.cc
+++ b/winsup/cygwin/fhandler_proc.cc
@@ -195,27 +195,32 @@ fhandler_proc::fstat (struct __stat64 *buf)
   return -1;
 }
 
-struct dirent *
-fhandler_proc::readdir (DIR * dir)
+int
+fhandler_proc::readdir (DIR *dir, dirent *de)
 {
-  if (dir->__d_position >= PROC_LINK_COUNT)
+  int res;
+  if (dir->__d_position < PROC_LINK_COUNT)
+    {
+      strcpy (de->d_name, proc_listing[dir->__d_position++]);
+      res = 0;
+    }
+  else
     {
       winpids pids ((DWORD) 0);
       int found = 0;
+      res = ENMFILE;
       for (unsigned i = 0; i < pids.npids; i++)
 	if (found++ == dir->__d_position - PROC_LINK_COUNT)
 	  {
-	    __small_sprintf (dir->__d_dirent->d_name, "%d", pids[i]->pid);
+	    __small_sprintf (de->d_name, "%d", pids[i]->pid);
 	    dir->__d_position++;
-	    return dir->__d_dirent;
+	    res = 0;
+	    break;
 	  }
-      return NULL;
     }
 
-  strcpy (dir->__d_dirent->d_name, proc_listing[dir->__d_position++]);
-  syscall_printf ("%p = readdir (%p) (%s)", &dir->__d_dirent, dir,
-		  dir->__d_dirent->d_name);
-  return dir->__d_dirent;
+  syscall_printf ("%d = readdir (%p, %p) (%s)", res, dir, de, de->d_name);
+  return res;
 }
 
 int
diff --git a/winsup/cygwin/fhandler_process.cc b/winsup/cygwin/fhandler_process.cc
index 7cc53302f..1585c2fea 100644
--- a/winsup/cygwin/fhandler_process.cc
+++ b/winsup/cygwin/fhandler_process.cc
@@ -209,30 +209,28 @@ fhandler_process::opendir ()
   return dir;
 }
 
-struct dirent *
-fhandler_process::readdir (DIR * dir)
+int
+fhandler_process::readdir (DIR *dir, dirent *de)
 {
+  int res = ENMFILE;
   if (fileid == PROCESS_FD)
     {
       if (dir->__d_position >= 2 + filesize / sizeof (int))
-	return NULL;
+	goto out;
     }
   else if (dir->__d_position >= PROCESS_LINK_COUNT)
-    return NULL;
+    goto out;
   if (fileid == PROCESS_FD && dir->__d_position > 1)
     {
       int *p = (int *) filebuf;
-      __small_sprintf (dir->__d_dirent->d_name, "%d", p[dir->__d_position++ - 2]);
-      syscall_printf ("%p = readdir (%p) (%s)", &dir->__d_dirent, dir,
-		      dir->__d_dirent->d_name);
+      __small_sprintf (de->d_name, "%d", p[dir->__d_position++ - 2]);
     }
   else
-    {
-      strcpy (dir->__d_dirent->d_name, process_listing[dir->__d_position++]);
-      syscall_printf ("%p = readdir (%p) (%s)", &dir->__d_dirent, dir,
-		      dir->__d_dirent->d_name);
-    }
-  return dir->__d_dirent;
+    strcpy (de->d_name, process_listing[dir->__d_position++]);
+  res = 0;
+out:
+  syscall_printf ("%d = readdir (%p, %p) (%s)", dir, de, de->d_name);
+  return res;
 }
 
 int
diff --git a/winsup/cygwin/fhandler_registry.cc b/winsup/cygwin/fhandler_registry.cc
index 07be1d0c7..885a35247 100644
--- a/winsup/cygwin/fhandler_registry.cc
+++ b/winsup/cygwin/fhandler_registry.cc
@@ -273,26 +273,25 @@ fhandler_registry::fstat (struct __stat64 *buf)
   return 0;
 }
 
-struct dirent *
-fhandler_registry::readdir (DIR * dir)
+int
+fhandler_registry::readdir (DIR *dir, dirent *de)
 {
   DWORD buf_size = CYG_MAX_PATH;
   char buf[buf_size];
   HANDLE handle;
-  struct dirent *res = NULL;
   const char *path = dir->__d_dirname + proc_len + 1 + registry_len;
   LONG error;
+  int res = ENMFILE;
 
   if (*path == 0)
     {
       if (dir->__d_position >= ROOT_KEY_COUNT)
 	goto out;
-      strcpy (dir->__d_dirent->d_name, registry_listing[dir->__d_position++]);
-      res = dir->__d_dirent;
+      strcpy (de->d_name, registry_listing[dir->__d_position++]);
+      res = 0;
       goto out;
     }
-  if (dir->__handle == INVALID_HANDLE_VALUE
-      && dir->__d_position == 0)
+  if (dir->__handle == INVALID_HANDLE_VALUE && dir->__d_position == 0)
     {
       handle = open_key (path + 1, KEY_READ, false);
       dir->__handle = handle;
@@ -301,9 +300,8 @@ fhandler_registry::readdir (DIR * dir)
     goto out;
   if (dir->__d_position < SPECIAL_DOT_FILE_COUNT)
     {
-      strcpy (dir->__d_dirent->d_name,
-	      special_dot_files[dir->__d_position++]);
-      res = dir->__d_dirent;
+      strcpy (de->d_name, special_dot_files[dir->__d_position++]);
+      res = 0;
       goto out;
     }
 retry:
@@ -338,16 +336,16 @@ retry:
 
   /* We get here if `buf' contains valid data.  */
   if (*buf == 0)
-    strcpy (dir->__d_dirent->d_name, DEFAULT_VALUE_NAME);
+    strcpy (de->d_name, DEFAULT_VALUE_NAME);
   else
-    strcpy (dir->__d_dirent->d_name, buf);
+    strcpy (de->d_name, buf);
 
   dir->__d_position++;
   if (dir->__d_position & REG_ENUM_VALUES_MASK)
     dir->__d_position += 0x10000;
-  res = dir->__d_dirent;
+  res = 0;
 out:
-  syscall_printf ("%p = readdir (%p)", &dir->__d_dirent, dir);
+  syscall_printf ("%d = readdir (%p, %p)", res, dir, de);
   return res;
 }
 
@@ -365,7 +363,7 @@ fhandler_registry::seekdir (DIR * dir, _off64_t loc)
    */
   rewinddir (dir);
   while (loc > (dir->__d_position & REG_POSITION_MASK))
-    if (!readdir (dir))
+    if (!readdir (dir, dir->__d_dirent))
       break;
 }
 
diff --git a/winsup/cygwin/include/cygwin/version.h b/winsup/cygwin/include/cygwin/version.h
index d5e97953b..7984df7f2 100644
--- a/winsup/cygwin/include/cygwin/version.h
+++ b/winsup/cygwin/include/cygwin/version.h
@@ -265,12 +265,13 @@ details. */
       136: Add TIOCMBIS/TIOCMBIC ioctl codes.
       137: fts_children, fts_close, fts_get_clientptr, fts_get_stream,
 	   fts_open, fts_read, fts_set, fts_set_clientptr, ftw, nftw.
+      138: Export readdir_r.
      */
 
      /* Note that we forgot to bump the api for ualarm, strtoll, strtoull */
 
 #define CYGWIN_VERSION_API_MAJOR 0
-#define CYGWIN_VERSION_API_MINOR 137
+#define CYGWIN_VERSION_API_MINOR 138
 
      /* There is also a compatibity version number associated with the
 	shared memory regions.  It is incremented when incompatible
diff --git a/winsup/cygwin/include/sys/dirent.h b/winsup/cygwin/include/sys/dirent.h
index 996b1ee33..5eafbc27b 100644
--- a/winsup/cygwin/include/sys/dirent.h
+++ b/winsup/cygwin/include/sys/dirent.h
@@ -68,6 +68,7 @@ typedef struct __DIR
 
 DIR *opendir (const char *);
 struct dirent *readdir (DIR *);
+int readdir_r (DIR *, struct dirent *, struct dirent **);
 void rewinddir (DIR *);
 int closedir (DIR *);