--- /dev/null
+/* Test that dup_safer leaves standard fds alone.
+ Copyright (C) 2009 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 <http://www.gnu.org/licenses/>. */
+
+/* Written by Eric Blake <ebb9@byu.net>, 2009. */
+
+#include <config.h>
+
+#include "unistd--.h"
+
+#include <fcntl.h>
+#include <errno.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/stat.h>
+
+#include "binary-io.h"
+#include "cloexec.h"
+
+#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
+/* Get declarations of the Win32 API functions. */
+# define WIN32_LEAN_AND_MEAN
+# include <windows.h>
+#endif
+
+#if !O_BINARY
+# define setmode(f,m) zero ()
+static int zero (void) { return 0; }
+#endif
+#ifndef O_CLOEXEC
+# define O_CLOEXEC 0
+#endif
+
+/* This test intentionally closes stderr. So, we arrange to have fd 10
+ (outside the range of interesting fd's during the test) set up to
+ duplicate the original stderr. */
+
+#define BACKUP_STDERR_FILENO 10
+static FILE *myerr;
+
+#define ASSERT(expr) \
+ do \
+ { \
+ if (!(expr)) \
+ { \
+ fprintf (myerr, "%s:%d: assertion failed\n", __FILE__, __LINE__); \
+ fflush (myerr); \
+ abort (); \
+ } \
+ } \
+ while (0)
+
+/* Return true if FD is open. */
+static bool
+is_open (int fd)
+{
+#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
+ /* On Win32, the initial state of unassigned standard file
+ descriptors is that they are open but point to an
+ INVALID_HANDLE_VALUE, and there is no fcntl. */
+ return (HANDLE) _get_osfhandle (fd) != INVALID_HANDLE_VALUE;
+#else
+# ifndef F_GETFL
+# error Please port fcntl to your platform
+# endif
+ return 0 <= fcntl (fd, F_GETFL);
+#endif
+}
+
+/* Return true if FD is open and inheritable across exec/spawn. */
+static bool
+is_inheritable (int fd)
+{
+#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
+ /* On Win32, the initial state of unassigned standard file
+ descriptors is that they are open but point to an
+ INVALID_HANDLE_VALUE, and there is no fcntl. */
+ HANDLE h = (HANDLE) _get_osfhandle (fd);
+ DWORD flags;
+ if (h == INVALID_HANDLE_VALUE || GetHandleInformation (h, &flags) == 0)
+ return 0;
+ return (flags & HANDLE_FLAG_INHERIT) != 0;
+#else
+# ifndef F_GETFD
+# error Please port fcntl to your platform
+# endif
+ int i = fcntl (fd, F_GETFD);
+ return 0 <= i && (i & FD_CLOEXEC) == 0;
+#endif
+}
+
+/* Return true if FD is open in the given MODE, which is either
+ O_TEXT or O_BINARY. */
+static bool
+is_mode (int fd, int mode)
+{
+ int value = setmode (fd, O_BINARY);
+ setmode (fd, value);
+ return mode == value;
+}
+
+#define witness "test-dup-safer.txt"
+
+int
+main (void)
+{
+ int i;
+ int fd;
+
+ /* We close fd 2 later, so save it in fd 10. */
+ if (dup2 (STDERR_FILENO, BACKUP_STDERR_FILENO) != BACKUP_STDERR_FILENO
+ || (myerr = fdopen (BACKUP_STDERR_FILENO, "w")) == NULL)
+ return 2;
+
+ /* Create file for later checks. */
+ fd = creat (witness, 0600);
+ ASSERT (STDERR_FILENO < fd);
+
+ /* Four iterations, with progressively more standard descriptors
+ closed. */
+ for (i = -1; i <= STDERR_FILENO; i++)
+ {
+ if (0 <= i)
+ ASSERT (close (i) == 0);
+
+ /* Detect errors. */
+ errno = 0;
+ ASSERT (dup (-1) == -1);
+ ASSERT (errno == EBADF);
+ errno = 0;
+ ASSERT (dup (10000000) == -1);
+ ASSERT (errno == EBADF);
+ close (fd + 1);
+ errno = 0;
+ ASSERT (dup (fd + 1) == -1);
+ ASSERT (errno == EBADF);
+
+ /* Preserve text vs. binary. */
+ setmode (fd, O_BINARY);
+ ASSERT (dup (fd) == fd + 1);
+ ASSERT (is_open (fd + 1));
+ ASSERT (is_inheritable (fd + 1));
+ ASSERT (is_mode (fd + 1, O_BINARY));
+
+ ASSERT (close (fd + 1) == 0);
+ setmode (fd, O_TEXT);
+ ASSERT (dup (fd) == fd + 1);
+ ASSERT (is_open (fd + 1));
+ ASSERT (is_inheritable (fd + 1));
+ ASSERT (is_mode (fd + 1, O_TEXT));
+
+ /* Create cloexec copy. */
+ ASSERT (close (fd + 1) == 0);
+ ASSERT (fd_safer_flag (dup_cloexec (fd), O_CLOEXEC) == fd + 1);
+ ASSERT (set_cloexec_flag (fd + 1, true) == 0);
+ ASSERT (is_open (fd + 1));
+ ASSERT (!is_inheritable (fd + 1));
+ ASSERT (close (fd) == 0);
+
+ /* dup always creates inheritable copies. Also, check that
+ earliest slot past std fds is used. */
+ ASSERT (dup (fd + 1) == fd);
+ ASSERT (is_open (fd));
+ ASSERT (is_inheritable (fd));
+ ASSERT (close (fd + 1) == 0);
+ }
+
+ /* Cleanup. */
+ ASSERT (close (fd) == 0);
+ ASSERT (unlink (witness) == 0);
+
+ return 0;
+}
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