add directory gnu

gnu/glibc/glibc-1.03/hurd/setdtablesize.c

@@ -0,0 +1,86 @@
+/* Copyright (C) 1991, 1992 Free Software Foundation, Inc.
+This file is part of the GNU C Library.
+
+The GNU C 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.
+
+The GNU C 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 the GNU C Library; see the file COPYING.LIB.  If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA.  */
+
+#include <hurd.h>
+
+/* Change the size of the descriptor table.
+   You cannot shrink the table if any of the descriptors
+   which would be removed are being used.  */
+
+int
+setdtablesize (size_t size)
+{
+  int i;
+  struct _hurd_fd *table;
+
+  __mutex_lock (&_hurd_dtable_lock);
+
+  /* Check that no descriptors which are in use are going to disappear.  */
+  for (i = size; i < _hurd_dtable.size; ++i)
+    {
+      struct _hurd_fd *const d = &_hurd_dtable.d[i];
+
+      __spin_lock (&d->port.lock);
+      if (d->port.port != MACH_PORT_NULL)
+	{
+	  __spin_unlock (&d->port.lock);
+	  __mutex_unlock (&_hurd_dtable_lock);
+	  errno = EBUSY;
+	  return -1;
+	}
+    }
+
+  /* Resize the table.  */
+
+  if (_hurd_dtable_user_dealloc == NULL)
+    /* Noone is using the table.  We can relocate it.  */
+    table = realloc (_hurd_dtable.d, size * sizeof (*table));
+  else
+    /* Someone else is using the table.
+       We must make a new copy, and let them free the old one.  */
+    table = malloc (size * sizeof (*table));
+
+  if (table == NULL)
+    {
+      __mutex_unlock (&_hurd_dtable_lock);
+      return -1;
+    }
+
+  if (_hurd_dtable_user_dealloc != NULL)
+    {
+      *_hurd_dtable_user_dealloc = 1;
+      _hurd_dtable_user_dealloc = NULL;
+
+      memcpy (table, _hurd_dtable.d, _hurd_dtable.size * sizeof (table[0]));
+    }
+
+  /* If the table grew, initialize the new slots.  */
+  for (i = _hurd_dtable.size; i < size; ++i)
+    {
+      table[i].flags = 0;
+      _hurd_port_init (&table[i].port, MACH_PORT_NULL);
+      _hurd_port_init (&table[i].ctty, MACH_PORT_NULL);
+    }
+
+  _hurd_dtable.size = size;
+  _hurd_dtable.d = table;
+
+  __mutex_unlock (&_hurd_dtable_lock);
+
+  return 0;
+}