[email protected] wrote on Tue, Mar 29, 2011 at 14:46:39 -0000:
> Author: stsp
> Date: Tue Mar 29 14:46:38 2011
> New Revision: 1086607
> 
> URL: http://svn.apache.org/viewvc?rev=1086607&view=rev
> Log:
> Fix issue #3014, "svn log | head" should not print "Write error: Broken pipe".
> 
> Make svn and other commands exit silently (with EXIT_FAILURE) if a pipe write
> error occured. The rationale being that the process closing the pipe is also
> responsible for printing a related error message, if necessary.
> 
> * subversion/libsvn_subr/cmdline.c
>   (svn_cmdline_fputs, svn_cmdline_fflush): Return
>    SVN_ERR_IO_PIPE_WRITE_ERROR when writes fail due to EPIPE, so that
>    callers can choose to ignore this kind of error.
>   (svn_cmdline_handle_exit_error): Don't print message for pipe write errors.
> 
> * subversion/libsvn_subr/io.c
>   (do_io_file_wrapper_cleanup): Return SVN_ERR_IO_PIPE_WRITE_ERROR when writes
>    fail due to EPIPE.
> 
> * subversion/libsvn_subr/opt.c
>   (svn_opt_print_generic_help2): Don't print message for pipe write errors.
> 
> * subversion/svn/notify.c
>   (notify): Same.
> 
> * subversion/svn/main.c
>   (main): Same.
> 
> * subversion/svn/obliterate-cmd.c
>   (notify): Same.
> 
> * subversion/svnadmin/main.c
>   (main): Same.
> 
> * subversion/include/svn_error_codes.h
>   (SVN_ERR_IO_PIPE_WRITE_ERROR): New error code.
> 
> Modified: subversion/trunk/subversion/libsvn_subr/cmdline.c
> URL: 
> http://svn.apache.org/viewvc/subversion/trunk/subversion/libsvn_subr/cmdline.c?rev=1086607&r1=1086606&r2=1086607&view=diff
> ==============================================================================
> --- subversion/trunk/subversion/libsvn_subr/cmdline.c (original)
> +++ subversion/trunk/subversion/libsvn_subr/cmdline.c Tue Mar 29 14:46:38 2011
> @@ -338,7 +338,19 @@ svn_cmdline_fputs(const char *string, FI
>    if (fputs(out, stream) == EOF)
>      {
>        if (errno)
> -        return svn_error_wrap_apr(errno, _("Write error"));
> +        {
> +          err = svn_error_wrap_apr(errno, _("Write error"));
> +
> +          /* ### Issue #3014: Return a specific error for broken pipes,
> +           * ### with a single element in the error chain. */
> +          if (APR_STATUS_IS_EPIPE(err->apr_err))
> +            {
> +              svn_error_clear(err);

So you're doing:

* get error number
* construct an svn_error_t object (that's includes a few malloc()s)
* check error number
* destroy svn_error_t object

Won't it be simpler to avoid constructing the svn_error_t object in the
first place (when errno is EPIPE)?

> +              return svn_error_create(SVN_ERR_IO_PIPE_WRITE_ERROR, NULL, 
> NULL);
> +            }
> +          else
> +            return svn_error_return(err);
> +        }
>        else
>          return svn_error_create
>            (SVN_ERR_IO_WRITE_ERROR, NULL, NULL);
> @@ -355,7 +367,19 @@ svn_cmdline_fflush(FILE *stream)
>    if (fflush(stream) == EOF)
>      {
>        if (errno)
> -        return svn_error_wrap_apr(errno, _("Write error"));
> +        {
> +          svn_error_t *err = svn_error_wrap_apr(errno, _("Write error"));
> +
> +          /* ### Issue #3014: Return a specific error for broken pipes,
> +           * ### with a single element in the error chain. */
> +          if (APR_STATUS_IS_EPIPE(err->apr_err))
> +            {
> +              svn_error_clear(err);
> +              return svn_error_create(SVN_ERR_IO_PIPE_WRITE_ERROR, NULL, 
> NULL);
> +            }
> +          else
> +            return svn_error_return(err);
> +        }
>        else
>          return svn_error_create(SVN_ERR_IO_WRITE_ERROR, NULL, NULL);
>      }
> @@ -376,7 +400,15 @@ svn_cmdline_handle_exit_error(svn_error_
>                                apr_pool_t *pool,
>                                const char *prefix)
>  {
> -  svn_handle_error2(err, stderr, FALSE, prefix);
> +  /* Issue #3014:
> +   * Don't print anything on broken pipes. The pipe was likely
> +   * closed by the process at the other end. We expect that
> +   * process to perform error reporting as necessary.
> +   *
> +   * ### This assumes that there is only one error in a chain for
> +   * ### SVN_ERR_IO_PIPE_WRITE_ERROR. See svn_cmdline_fputs(). */
> +  if (err->apr_err != SVN_ERR_IO_PIPE_WRITE_ERROR)
> +    svn_handle_error2(err, stderr, FALSE, prefix);

This ### seems easy enough to avoid, isn't it?  i.e., why did you need
to assume a single-link chain?

>    svn_error_clear(err);
>    if (pool)
>      svn_pool_destroy(pool);
> 
> Modified: subversion/trunk/subversion/libsvn_subr/io.c
> URL: 
> http://svn.apache.org/viewvc/subversion/trunk/subversion/libsvn_subr/io.c?rev=1086607&r1=1086606&r2=1086607&view=diff
> ==============================================================================
> --- subversion/trunk/subversion/libsvn_subr/io.c (original)
> +++ subversion/trunk/subversion/libsvn_subr/io.c Tue Mar 29 14:46:38 2011
> @@ -3034,6 +3034,11 @@ do_io_file_wrapper_cleanup(apr_file_t *f
>      name = NULL;
>    svn_error_clear(err);
>  
> +  /* ### Issue #3014: Return a specific error for broken pipes,
> +   * ### with a single element in the error chain. */
> +  if (APR_STATUS_IS_EPIPE(status))
> +    return svn_error_create(SVN_ERR_IO_PIPE_WRITE_ERROR, NULL, NULL);
> +
>    if (name)
>      return svn_error_wrap_apr(status, _(msg),
>                                svn_dirent_local_style(name, pool));
> 
> Modified: subversion/trunk/subversion/libsvn_subr/opt.c
> URL: 
> http://svn.apache.org/viewvc/subversion/trunk/subversion/libsvn_subr/opt.c?rev=1086607&r1=1086606&r2=1086607&view=diff
> ==============================================================================
> --- subversion/trunk/subversion/libsvn_subr/opt.c (original)
> +++ subversion/trunk/subversion/libsvn_subr/opt.c Tue Mar 29 14:46:38 2011
> @@ -383,7 +383,15 @@ svn_opt_print_generic_help2(const char *
>    return;
>  
>   print_error:
> -  svn_handle_error2(err, stderr, FALSE, "svn: ");
> +  /* Issue #3014:
> +   * Don't print anything on broken pipes. The pipe was likely
> +   * closed by the process at the other end. We expect that
> +   * process to perform error reporting as necessary.
> +   *
> +   * ### This assumes that there is only one error in a chain for
> +   * ### SVN_ERR_IO_PIPE_WRITE_ERROR. See svn_cmdline_fputs(). */
> +  if (err->apr_err != SVN_ERR_IO_PIPE_WRITE_ERROR)
> +    svn_handle_error2(err, stderr, FALSE, "svn: ");

This bit of code (including the comment, the ###, and the specific
condition) is repeated N times below.

Abstract it into a private helper macro?

Reply via email to