Adding upstream version 1.21.3.upstream/1.21.3upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 52 insertions, 0 deletions

diff --git a/lib/pipe2-safer.c b/lib/pipe2-safer.c
new file mode 100644
index 0000000..3a84c66
--- /dev/null
+++ b/lib/pipe2-safer.c
@@ -0,0 +1,52 @@
+/* Invoke pipe2, but avoid some glitches.
+   Copyright (C) 2005-2006, 2009-2022 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 <https://www.gnu.org/licenses/>.  */
+
+/* Written by Eric Blake.  */
+
+#include <config.h>
+
+/* Specification.  */
+#include "unistd-safer.h"
+
+#include <unistd.h>
+#include <errno.h>
+
+/* Like pipe2, but ensure that neither of the file descriptors is
+   STDIN_FILENO, STDOUT_FILENO, or STDERR_FILENO.  */
+
+int
+pipe2_safer (int fd[2], int flags)
+{
+  /* This is a generalization of the pipe_safer implementation.  */
+  if (pipe2 (fd, flags) == 0)
+    {
+      int i;
+      for (i = 0; i < 2; i++)
+        {
+          fd[i] = fd_safer_flag (fd[i], flags);
+          if (fd[i] < 0)
+            {
+              int e = errno;
+              close (fd[1 - i]);
+              errno = e;
+              return -1;
+            }
+        }
+
+      return 0;
+    }
+  return -1;
+}