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, 2 insertions, 0 deletions

diff --git a/sysdeps/mach/hurd/dl-sysdep.c b/sysdeps/mach/hurd/dl-sysdep.c
index 1626cd5..a4eab4c 100644
--- a/sysdeps/mach/hurd/dl-sysdep.c
+++ b/sysdeps/mach/hurd/dl-sysdep.c
@@ -396,6 +396,7 @@ libc_hidden_weak (__read)
 weak_alias (__read, __read_nocancel)
 
 check_no_hidden(__write);
+check_no_hidden(__write_nocancel);
 __ssize_t weak_function
 __write (int fd, const void *buf, size_t nbytes)
 {
@@ -411,6 +412,7 @@ __write (int fd, const void *buf, size_t nbytes)
   return nwrote;
 }
 libc_hidden_weak (__write)
+  weak_alias (__write, __write_nocancel)
 
 /* This is only used for printing messages (see dl-misc.c).  */
 check_no_hidden(__writev);