1 files changed, 83 insertions, 0 deletions
diff --git a/gnulib-tests/test-fsync.c b/gnulib-tests/test-fsync.c
new file mode 100644
index 0000000..f0e3a95
--- /dev/null
+++ b/gnulib-tests/test-fsync.c
@@ -0,0 +1,83 @@
+/* Test of fsync() function.
+   Copyright (C) 2008-2022 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/>.  */
+
+#include <config.h>
+
+#include <unistd.h>
+
+#include "signature.h"
+SIGNATURE_CHECK (fsync, int, (int));
+
+#include <errno.h>
+#include <fcntl.h>
+
+#include "macros.h"
+
+int
+main (void)
+{
+  int fd;
+  const char *file = "test-fsync.txt";
+
+  /* Assuming stdin and stdout are ttys, fsync is allowed to fail, but
+     may succeed as an extension.  */
+  for (fd = 0; fd < 2; fd++)
+    if (fsync (fd) != 0)
+      {
+        ASSERT (errno == EINVAL /* POSIX */
+                || errno == ENOTSUP /* seen on Mac OS X 10.5 */
+                || errno == EBADF /* seen on AIX 7.1 */
+                || errno == EIO /* seen on mingw */
+                );
+      }
+
+  /* fsync must fail on invalid fd.  */
+  {
+    errno = 0;
+    ASSERT (fsync (-1) == -1);
+    ASSERT (errno == EBADF);
+  }
+  {
+    close (99);
+    errno = 0;
+    ASSERT (fsync (99) == -1);
+    ASSERT (errno == EBADF);
+  }
+
+  fd = open (file, O_WRONLY|O_CREAT|O_TRUNC, 0644);
+  ASSERT (0 <= fd);
+  ASSERT (write (fd, "hello", 5) == 5);
+  ASSERT (fsync (fd) == 0);
+  ASSERT (close (fd) == 0);
+
+  /* For a read-only regular file input file descriptor, fsync should
+     succeed (since at least atime changes can be synchronized).
+     On AIX and Cygwin, this test would fail.  */
+#if !(defined _AIX || defined __CYGWIN__)
+  fd = open (file, O_RDONLY);
+  ASSERT (0 <= fd);
+  {
+    char buf[1];
+    ASSERT (read (fd, buf, sizeof buf) == sizeof buf);
+  }
+  ASSERT (fsync (fd) == 0);
+  ASSERT (close (fd) == 0);
+#endif
+
+  ASSERT (unlink (file) == 0);
+
+  return 0;
+}