[patch/rfc] Zap error_begin(), juggle verror() and error_stream()

[Andrew Cagney <ac131313 at cygnus dot com>]

Hello,

This patch zaps the now defunct error_begin() function.

It then swaps the verror() and error_stream() function bodies so that 
verror() uses error_stream() instead of the reverse.

error_stream() uses uses the more efficient ui_file_put() to copy the 
message buffer to gdb_stderr and gdb_errbuf (verror() was using 
ui_file_xstrdup()).  On the other hand, verror() creates a ui_file 
before calling error_string().  What was gained on the swings was lost 
on the roundabouts.

enjoy,
Andrew
2002-01-31  Andrew Cagney  <ac131313@redhat.com>

	* defs.h (error_begin): Delete function.

	* utils.c (do_write): New function.
	(error_stream): Rewrite combining the code from error_begin and
	verror.
	(verror): Rewrite using error_stream.
	(error_begin): Delete function.

diff --exclude *CVS* --exclude *#* --exclude *~* --exclude *%* --exclude *.orig --exclude *.rej --exclude *diffs --exclude new-* --exclude old-* --exclude *-new --exclude *-old -c /home/scratch/PENDING/2002-01-31-error-begin/src/gdb/utils.c ./utils.c
*** /home/scratch/PENDING/2002-01-31-error-begin/src/gdb/utils.c	Thu Jan 31 10:59:39 2002
--- ./utils.c	Thu Jan 31 14:14:37 2002
***************
*** 593,621 ****
    va_end (args);
  }
  
- /* Start the printing of an error message.  Way to use this is to call
-    this, output the error message (use filtered output to gdb_stderr
-    (FIXME: Some callers, like memory_error, use gdb_stdout)), ending
-    in a newline, and then call return_to_top_level (RETURN_ERROR).
-    error() provides a convenient way to do this for the special case
-    that the error message can be formatted with a single printf call,
-    but this is more general.  */
- static void
- error_begin (void)
- {
-   if (error_begin_hook)
-     error_begin_hook ();
- 
-   target_terminal_ours ();
-   wrap_here ("");		/* Force out any buffered output */
-   gdb_flush (gdb_stdout);
- 
-   annotate_error_begin ();
- 
-   if (error_pre_print)
-     fprintf_filtered (gdb_stderr, error_pre_print);
- }
- 
  /* Print an error message and return to command level.
     The first argument STRING is the error message, used as a fprintf string,
     and the remaining args are passed as arguments to it.  */
--- 593,598 ----
***************
*** 623,651 ****
  NORETURN void
  verror (const char *string, va_list args)
  {
!   char *err_string;
!   struct cleanup *err_string_cleanup;
!   /* FIXME: cagney/1999-11-10: All error calls should come here.
!      Unfortunately some code uses the sequence: error_begin(); print
!      error message; return_to_top_level.  That code should be
!      flushed. */
!   error_begin ();
!   /* NOTE: It's tempting to just do the following...
! 	vfprintf_filtered (gdb_stderr, string, args);
!      and then follow with a similar looking statement to cause the message
!      to also go to gdb_lasterr.  But if we do this, we'll be traversing the
!      va_list twice which works on some platforms and fails miserably on
!      others. */
!   /* Save it as the last error */
!   ui_file_rewind (gdb_lasterr);
!   vfprintf_filtered (gdb_lasterr, string, args);
!   /* Retrieve the last error and print it to gdb_stderr */
!   err_string = error_last_message ();
!   err_string_cleanup = make_cleanup (xfree, err_string);
!   fputs_filtered (err_string, gdb_stderr);
!   fprintf_filtered (gdb_stderr, "\n");
!   do_cleanups (err_string_cleanup);
!   return_to_top_level (RETURN_ERROR);
  }
  
  NORETURN void
--- 600,609 ----
  NORETURN void
  verror (const char *string, va_list args)
  {
!   struct ui_file *tmp_stream = mem_fileopen ();
!   make_cleanup_ui_file_delete (tmp_stream);
!   vfprintf_unfiltered (tmp_stream, string, args);
!   error_stream (tmp_stream);
  }
  
  NORETURN void
***************
*** 657,669 ****
    va_end (args);
  }
  
  NORETURN void
  error_stream (struct ui_file *stream)
  {
!   long size;
!   char *msg = ui_file_xstrdup (stream, &size);
!   make_cleanup (xfree, msg);
!   error ("%s", msg);
  }
  
  /* Get the last error message issued by gdb */
--- 615,647 ----
    va_end (args);
  }
  
+ static void
+ do_write (void *data, const char *buffer, long length_buffer)
+ {
+   ui_file_write (data, buffer, length_buffer);
+ }
+ 
  NORETURN void
  error_stream (struct ui_file *stream)
  {
!   if (error_begin_hook)
!     error_begin_hook ();
! 
!   /* Copy the stream into the GDB_LASTERR buffer.  */
!   ui_file_rewind (gdb_lasterr);
!   ui_file_put (stream, do_write, gdb_lasterr);
! 
!   /* Write the message plus any error_pre_print to gdb_stderr.  */
!   target_terminal_ours ();
!   wrap_here ("");		/* Force out any buffered output */
!   gdb_flush (gdb_stdout);
!   annotate_error_begin ();
!   if (error_pre_print)
!     fprintf_filtered (gdb_stderr, error_pre_print);
!   ui_file_put (stream, do_write, gdb_stderr);
!   fprintf_filtered (gdb_stderr, "\n");
! 
!   return_to_top_level (RETURN_ERROR);
  }
  
  /* Get the last error message issued by gdb */