hurd: Make write and pwrite64 cancellation points

and add _nocancel variants.

* sysdeps/mach/hurd/write.c (__libc_write): Call __write_nocancel
surrounded by enabling async cancel, to replace implementation moved
to...
* sysdeps/mach/hurd/write_nocancel.c (__write_nocancel): ... here.
* sysdeps/mach/hurd/pwrite64.c (__libc_pwrite64): Call
__pwrite64_nocancel surrounded by enabling async cancel, to replace
implementation moved to...
* sysdeps/mach/hurd/pwrite64_nocancel.c (__pwrite64_nocancel): ... here.
* sysdeps/mach/hurd/Makefile (sysdep_routines): Add write_nocancel and
pwrite64_nocancel.
* sysdeps/mach/hurd/not-cancel.h (__write_nocancel,
__pwrite64_nocancel): Replace macros with prototypes with a hidden proto on
libc.

* sysdeps/mach/hurd/dl-sysdep.c (__write_nocancel): New alias, check
that it is not hidden.
* sysdeps/mach/hurd/Versions (libc.GLIBC_PRIVATE): Add __write_nocancel.
(ld.GLIBC_PRIVATE): Add __write_nocancel.
* sysdeps/mach/hurd/i386/localplt.data (__write_nocancel): Add
reference.

1 files changed, 7 insertions, 6 deletions

diff --git a/sysdeps/mach/hurd/write.c b/sysdeps/mach/hurd/write.c
index 9e1ade8801..0eea22be4b 100644
--- a/sysdeps/mach/hurd/write.c
+++ b/sysdeps/mach/hurd/write.c
@@ -15,16 +15,17 @@
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#include <errno.h>
-#include <unistd.h>
-#include <hurd/fd.h>
+#include <sysdep-cancel.h>
+#include <not-cancel.h>
 
 ssize_t
 __libc_write (int fd, const void *buf, size_t nbytes)
 {
-  error_t err = HURD_FD_USE (fd, _hurd_fd_write (descriptor,
-						 buf, &nbytes, -1));
-  return err ? __hurd_dfail (fd, err) : nbytes;
+  ssize_t ret;
+  int cancel_oldtype = LIBC_CANCEL_ASYNC();
+  ret = __write_nocancel (fd, buf, nbytes);
+  LIBC_CANCEL_RESET (cancel_oldtype);
+  return ret;
 }
 libc_hidden_def (__libc_write)
 weak_alias (__libc_write, __write)