Merge branch 'feature/upstream' into develop

1 files changed, 183 insertions, 0 deletions

diff --git a/tests/test-dup-safer.c b/tests/test-dup-safer.c
new file mode 100644
index 00000000..ec2cb908
--- /dev/null
+++ b/tests/test-dup-safer.c
@@ -0,0 +1,183 @@
+/* Test that dup_safer leaves standard fds alone.
+   Copyright (C) 2009-2024 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 <ebb9@byu.net>, 2009.  */
+
+#include <config.h>
+
+#include "unistd--.h"
+
+#include <fcntl.h>
+#include <errno.h>
+#include <stdio.h>
+#include <unistd.h>
+
+#include "binary-io.h"
+#include "cloexec.h"
+
+#if defined _WIN32 && ! defined __CYGWIN__
+/* Get declarations of the native Windows API functions.  */
+# define WIN32_LEAN_AND_MEAN
+# include <windows.h>
+/* Get _get_osfhandle.  */
+# if GNULIB_MSVC_NOTHROW
+#  include "msvc-nothrow.h"
+# else
+#  include <io.h>
+# endif
+#endif
+
+#if !O_BINARY
+# define set_binary_mode my_set_binary_mode
+static int
+set_binary_mode (_GL_UNUSED int fd, _GL_UNUSED int mode)
+{
+  return 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
+#define ASSERT_STREAM myerr
+#include "macros.h"
+
+static FILE *myerr;
+
+/* Return true if FD is open.  */
+static bool
+is_open (int fd)
+{
+#if defined _WIN32 && ! defined __CYGWIN__
+  /* On native Windows, 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 __CYGWIN__
+  /* On native Windows, 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 = set_binary_mode (fd, O_BINARY);
+  set_binary_mode (fd, value);
+  return mode == value;
+}
+
+#define witness "test-dup-safer.txt"
+
+int
+main (void)
+{
+  int i;
+  int fd;
+  int bad_fd = getdtablesize ();
+
+  /* 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 (bad_fd) == -1);
+      ASSERT (errno == EBADF);
+      close (fd + 1);
+      errno = 0;
+      ASSERT (dup (fd + 1) == -1);
+      ASSERT (errno == EBADF);
+
+      /* Preserve text vs. binary.  */
+      set_binary_mode (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);
+      set_binary_mode (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 test_exit_status;
+}