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-rw-r--r--io/close_range.c44
1 files changed, 44 insertions, 0 deletions
diff --git a/io/close_range.c b/io/close_range.c
new file mode 100644
index 0000000000..26a615d8b9
--- /dev/null
+++ b/io/close_range.c
@@ -0,0 +1,44 @@
+/* Close a range of file descriptors.
+   Copyright (C) 2021 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 Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#include <errno.h>
+#include <not-cancel.h>
+#include <unistd.h>
+
+/* Close the file descriptors from FIRST up to LAST, inclusive.  */
+int
+__close_range (unsigned int first, unsigned int last,
+	       int flags)
+{
+  if (first > last || flags != 0)
+    {
+      __set_errno (EINVAL);
+      return -1;
+    }
+
+  int maxfd = __getdtablesize ();
+  if (maxfd == -1)
+    return -1;
+
+  for (int i = first; i <= last && i < maxfd; i++)
+    __close_nocancel_nostatus (i);
+
+  return 0;
+}
+libc_hidden_def (__close_range)
+weak_alias (__close_range, close_range)