Cygwin: posix_fallocate: return ENODEV

The fhandler method ftruncate returns either EISDIR if it has been
called on directories, or EINVAL if called on files other than
regular files.  This matches what ftruncate(2) is supposed to return,
but it doesn't match posix_fallocate(3), which is supposed to return
ENODEV in both cases.

To accomplish that, return ENODEV from fhandler_base::ftruncate()
and convert it to EINVAL in ftruncate(2). In posix_fallocate(3),
convert EISDIR to ENODEV.

Fixes: 7636b58590 ("* autoload.cc (NtSetInformationFile): Define.")
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>

winsup/cygwin/fhandler/base.cc

@@ -1797,7 +1797,7 @@ fhandler_base::fadvise (off_t offset, off_t length, int advice)
 int
 fhandler_base::ftruncate (off_t length, bool allow_truncate)
 {
-  return EINVAL;
+  return ENODEV;
 }
 
 int

winsup/cygwin/release/3.4.10

@@ -18,3 +18,6 @@ Bug Fixes
 
 - Align behaviour of rand(3) to ISO C.
   Adresses: https://cygwin.com/pipermail/cygwin/2023-November/254735.html
+
+- Fix posix_fallocate(3) return value in case of being called on
+  other than regular files.

winsup/cygwin/syscalls.cc

@@ -3000,6 +3000,8 @@ posix_fallocate (int fd, off_t offset, off_t len)
 	res = cfd->ftruncate (offset + len, false);
       else
 	res = EBADF;
+      if (res == EISDIR)
+	res = ENODEV;
     }
   syscall_printf ("%R = posix_fallocate(%d, %D, %D)", res, fd, offset, len);
   return res;
@@ -3015,6 +3017,8 @@ ftruncate (int fd, off_t length)
       res = cfd->ftruncate (length, true);
       if (res)
 	{
+	  if (res == ENODEV)
+	    res = EINVAL;
 	  set_errno (res);
 	  res = -1;
 	}