On 2013-12-17 02:52, Chris Johns wrote:
On 17/12/2013 12:29 am, Sebastian Huber wrote:
Pass also zero-size buffers to the write handler since they may have
side-effects for non-regular files, e.g. sending of an empty message.

I agree regular files should follow the standard with others being unspecified.
I do not think this patch does this.

@@ -31,95 +29,31 @@ ssize_t writev(
  {
    ssize_t        total;
    int            v;
-  int            bytes;
    rtems_libio_t *iop;
-  ssize_t        old;
-  bool           all_zeros;

-  rtems_libio_check_fd( fd );
-  iop = rtems_libio_iop( fd );
-  rtems_libio_check_is_open( iop );
-  rtems_libio_check_permissions_with_error( iop, LIBIO_FLAGS_WRITE, EBADF );
-
-  /*
-   *  Argument validation on IO vector
-   */
-  if ( !iov )
-    rtems_set_errno_and_return_minus_one( EINVAL );
-
-  if ( iovcnt <= 0 )
-    rtems_set_errno_and_return_minus_one( EINVAL );
-
-  if ( iovcnt > IOV_MAX )
-    rtems_set_errno_and_return_minus_one( EINVAL );
-
-  /*
-   *  OpenGroup says that you are supposed to return EINVAL if the
-   *  sum of the iov_len values in the iov array would overflow a
-   *  ssize_t.
-   *
-   *  Also we would like to ensure that no IO is performed if there
-   *  are obvious errors in the iovec.  So this extra loop ensures
-   *  that we do not do anything if there is an argument error.
-   *
-   *  In addition,the OpenGroup specification says that if all the
-   *  iov_len entries are zero, then the call has no effect.  So
-   *  this loop does that check as well and sets "all-zero" appropriately.
-   *  The variable "all_zero" is used as an early exit point before
-   *  entering the write loop.
-   */
-  all_zeros = true;
-  for ( old=0, total=0, v=0 ; v < iovcnt ; v++ ) {
+  total = rtems_libio_iovec_eval( fd, iov, iovcnt, LIBIO_FLAGS_WRITE, &iop );

+  if ( total >= 0 ) {

I am not sure about this...

Ok, I will change this into "if ( total > 0 ) {" since I don't need the total == 0 case currently.

Is the rest ok?

--
Sebastian Huber, embedded brains GmbH

Address : Dornierstr. 4, D-82178 Puchheim, Germany
Phone   : +49 89 189 47 41-16
Fax     : +49 89 189 47 41-09
E-Mail  : sebastian.hu...@embedded-brains.de
PGP     : Public key available on request.

Diese Nachricht ist keine geschäftliche Mitteilung im Sinne des EHUG.
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