Re: [PATCH] gdb: Use puts_unfiltered instead of printf_unfiltered

[Iain Buclaw <ibuclaw@gdcproject.org>]

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‐‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐
On Tuesday, 26 November 2019 21:24, Pedro Alves <palves@redhat.com> wrote:

> On 11/26/19 12:49 PM, Iain Buclaw wrote:
>
> > The significance of this is that printf_unfiltered writes messages to wrap_buffer, whereas puts_unfiltered pushes them immediately to stdout, resulting in "post-" messages being printed out of order.
>
> It sounds quite surprising that two _unfiltered functions could behave differently
> like that. That sounds like a bug that should be fixed, instead of worked around
> by having to recall to use printf vs puts.
>
> Thanks,
> Pedro Alves

I think the best way to avoid the discrepancy is to treat both fputs_filtered and fputs_unfiltered equally by forwarding both calls to fputs_maybe_filtered.

To avoid recursion, flush_wrap_buffer and fputs_maybe_filtered have had calls to fputs_unfiltered replaced with stream->puts().

While attempting to grok my head around fputs_maybe_filtered, I also noticed that buffer_clearer is being removed by the compiler as dead code.

--
Iain

---
gdb/ChangeLog:

2019-11-26  Iain Buclaw  <ibuclaw@gdcproject.org>

	* gdb/ui-file.c (fputs_unfiltered): Move to utils.c.
	* gdb/utils.c (flush_wrap_buffer): Call ui_file::puts instead of
	fputs_unfiltered.
	(fputs_maybe_filtered): Likewise.  Remove unused buffer_clearer.
	(fputs_unfiltered): Moved from utils.c; call fputs_maybe_filtered.

---
 gdb/ui-file.c |  6 ------
 gdb/utils.c   | 22 +++++++++-------------
 2 files changed, 9 insertions(+), 19 deletions(-)

---



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diff --git a/gdb/ui-file.c b/gdb/ui-file.c
index 71b74bba19..31664d5d65 100644
--- a/gdb/ui-file.c
+++ b/gdb/ui-file.c
@@ -149,12 +149,6 @@ ui_file_read (struct ui_file *file, char *buf, long length_buf)
   return file->read (buf, length_buf);
 }
 
-void
-fputs_unfiltered (const char *buf, struct ui_file *file)
-{
-  file->puts (buf);
-}
-
 \f
 
 string_file::~string_file ()
diff --git a/gdb/utils.c b/gdb/utils.c
index f7fae35729..e8cc21c8c4 100644
--- a/gdb/utils.c
+++ b/gdb/utils.c
@@ -1539,7 +1539,7 @@ flush_wrap_buffer (struct ui_file *stream)
 {
   if (stream == gdb_stdout && !wrap_buffer.empty ())
     {
-      fputs_unfiltered (wrap_buffer.c_str (), stream);
+      stream->puts (wrap_buffer.c_str ());
       wrap_buffer.clear ();
     }
 }
@@ -1688,18 +1688,10 @@ fputs_maybe_filtered (const char *linebuffer, struct ui_file *stream,
       || top_level_interpreter ()->interp_ui_out ()->is_mi_like_p ())
     {
       flush_wrap_buffer (stream);
-      fputs_unfiltered (linebuffer, stream);
+      stream->puts (linebuffer);
       return;
     }
 
-  auto buffer_clearer
-    = make_scope_exit ([&] ()
-		       {
-			 wrap_buffer.clear ();
-			 wrap_column = 0;
-			 wrap_indent = "";
-		       });
-
   /* Go through and output each character.  Show line extension
      when this is necessary; prompt user for new page when this is
      necessary.  */
@@ -1788,7 +1780,7 @@ fputs_maybe_filtered (const char *linebuffer, struct ui_file *stream,
 	      /* Now output indentation and wrapped string.  */
 	      if (wrap_column)
 		{
-		  fputs_unfiltered (wrap_indent, stream);
+		  stream->puts (wrap_indent);
 		  if (stream->can_emit_style_escape ())
 		    emit_style_escape (save_style, stream);
 		  /* FIXME, this strlen is what prevents wrap_indent from
@@ -1816,8 +1808,6 @@ fputs_maybe_filtered (const char *linebuffer, struct ui_file *stream,
 	  lineptr++;
 	}
     }
-
-  buffer_clearer.release ();
 }
 
 void
@@ -1826,6 +1816,12 @@ fputs_filtered (const char *linebuffer, struct ui_file *stream)
   fputs_maybe_filtered (linebuffer, stream, 1);
 }
 
+void
+fputs_unfiltered (const char *linebuffer, struct ui_file *stream)
+{
+  fputs_maybe_filtered (linebuffer, stream, 0);
+}
+
 /* See utils.h.  */
 
 void