[PATCH 4/4] Switch gdb_stdlog to use timestamped_file

[Tom Tromey <tom@tromey.com>]

Currently, timestamps for logging are done by looking for the use of
gdb_stdlog in vfprintf_unfiltered.  This seems potentially buggy, in
that during logging or other redirects (like execute_fn_to_ui_file) we
might have gdb_stdout==gdb_stdlog and so, conceivably, wind up with
timestamps in a log when they were not desired.

It seems better, instead, for timestamps to be a property of the
ui_file itself.

This patch changes gdb to use the new timestamped_file for gdb_stdlog
where appropriate, and removes the special case from
vfprintf_unfiltered.

Note that this may somewhat change the output in some cases -- in
particular, when going through execute_fn_to_ui_file (or the _string
variant), timestamps won't be emitted.  This could be fixed in those
functions, but it wasn't clear to me whether this is really desirable.

Note also that this changes the TUI to send gdb_stdlog to gdb_stderr.
I imagine that the previous use of gdb_stdout here was inadvertent.
(And in any case it probably doesn't matter.)
---
 gdb/cli/cli-interp.c |  6 +++++-
 gdb/event-top.c      |  2 +-
 gdb/tui/tui-io.c     |  8 ++++++--
 gdb/utils.c          | 30 +-----------------------------
 4 files changed, 13 insertions(+), 33 deletions(-)

diff --git a/gdb/cli/cli-interp.c b/gdb/cli/cli-interp.c
index 031ab10aea6..c52a5f10a18 100644
--- a/gdb/cli/cli-interp.c
+++ b/gdb/cli/cli-interp.c
@@ -396,6 +396,7 @@ struct saved_output_files
   ui_file *targ;
   ui_file *targerr;
   ui_file_up file_to_delete;
+  ui_file_up log_to_delete;
 };
 static std::unique_ptr<saved_output_files> saved_output;
 
@@ -426,8 +427,11 @@ cli_interp_base::set_logging (ui_file_up logfile, bool logging_redirect,
       else
 	saved_output->file_to_delete = std::move (logfile);
 
+      saved_output->log_to_delete.reset
+	(new timestamped_file (debug_redirect ? logfile_p : tee));
+
       gdb_stdout = logging_redirect ? logfile_p : tee;
-      gdb_stdlog = debug_redirect ? logfile_p : tee;
+      gdb_stdlog = saved_output->log_to_delete.get ();
       gdb_stderr = logging_redirect ? logfile_p : tee;
       gdb_stdtarg = logging_redirect ? logfile_p : tee;
       gdb_stdtargerr = logging_redirect ? logfile_p : tee;
diff --git a/gdb/event-top.c b/gdb/event-top.c
index 530ea298247..80ac1e4a61e 100644
--- a/gdb/event-top.c
+++ b/gdb/event-top.c
@@ -1285,7 +1285,7 @@ gdb_setup_readline (int editing)
   if (!batch_silent)
     gdb_stdout = new stdio_file (ui->outstream);
   gdb_stderr = new stderr_file (ui->errstream);
-  gdb_stdlog = gdb_stderr;  /* for moment */
+  gdb_stdlog = new timestamped_file (gdb_stderr);
   gdb_stdtarg = gdb_stderr; /* for moment */
   gdb_stdtargerr = gdb_stderr; /* for moment */
 
diff --git a/gdb/tui/tui-io.c b/gdb/tui/tui-io.c
index bd443dc0c0c..58996df7924 100644
--- a/gdb/tui/tui-io.c
+++ b/gdb/tui/tui-io.c
@@ -108,11 +108,13 @@ key_is_start_sequence (int ch)
 /* TUI output files.  */
 static struct ui_file *tui_stdout;
 static struct ui_file *tui_stderr;
+static struct ui_file *tui_stdlog;
 struct ui_out *tui_out;
 
 /* GDB output files in non-curses mode.  */
 static struct ui_file *tui_old_stdout;
 static struct ui_file *tui_old_stderr;
+static struct ui_file *tui_old_stdlog;
 cli_ui_out *tui_old_uiout;
 
 /* Readline previous hooks.  */
@@ -828,13 +830,14 @@ tui_setup_io (int mode)
       /* Keep track of previous gdb output.  */
       tui_old_stdout = gdb_stdout;
       tui_old_stderr = gdb_stderr;
+      tui_old_stdlog = gdb_stdlog;
       tui_old_uiout = dynamic_cast<cli_ui_out *> (current_uiout);
       gdb_assert (tui_old_uiout != nullptr);
 
       /* Reconfigure gdb output.  */
       gdb_stdout = tui_stdout;
       gdb_stderr = tui_stderr;
-      gdb_stdlog = gdb_stdout;	/* for moment */
+      gdb_stdlog = tui_stdlog;
       gdb_stdtarg = gdb_stderr;	/* for moment */
       gdb_stdtargerr = gdb_stderr;	/* for moment */
       current_uiout = tui_out;
@@ -847,7 +850,7 @@ tui_setup_io (int mode)
       /* Restore gdb output.  */
       gdb_stdout = tui_old_stdout;
       gdb_stderr = tui_old_stderr;
-      gdb_stdlog = gdb_stdout;	/* for moment */
+      gdb_stdlog = tui_old_stdlog;
       gdb_stdtarg = gdb_stderr;	/* for moment */
       gdb_stdtargerr = gdb_stderr;	/* for moment */
       current_uiout = tui_old_uiout;
@@ -902,6 +905,7 @@ tui_initialize_io (void)
   /* Create tui output streams.  */
   tui_stdout = new tui_file (stdout);
   tui_stderr = new tui_file (stderr);
+  tui_stdlog = new timestamped_file (tui_stderr);
   tui_out = tui_out_new (tui_stdout);
 
   /* Create the default UI.  */
diff --git a/gdb/utils.c b/gdb/utils.c
index fc460d20321..13d431c5301 100644
--- a/gdb/utils.c
+++ b/gdb/utils.c
@@ -2060,35 +2060,7 @@ vfprintf_filtered (struct ui_file *stream, const char *format, va_list args)
 void
 vfprintf_unfiltered (struct ui_file *stream, const char *format, va_list args)
 {
-  if (debug_timestamp && stream == gdb_stdlog)
-    {
-      static bool needs_timestamp = true;
-
-      /* Print timestamp if previous print ended with a \n.  */
-      if (needs_timestamp)
-	{
-	  using namespace std::chrono;
-
-	  steady_clock::time_point now = steady_clock::now ();
-	  seconds s = duration_cast<seconds> (now.time_since_epoch ());
-	  microseconds us = duration_cast<microseconds> (now.time_since_epoch () - s);
-	  std::string timestamp = string_printf ("%ld.%06ld ",
-						 (long) s.count (),
-						 (long) us.count ());
-	  fputs_unfiltered (timestamp.c_str (), stream);
-	}
-
-      /* Print the message.  */
-      string_file sfile;
-      cli_ui_out (&sfile, 0).vmessage (ui_file_style (), format, args);
-      std::string linebuffer = std::move (sfile.string ());
-      fputs_unfiltered (linebuffer.c_str (), stream);
-
-      size_t len = linebuffer.length ();
-      needs_timestamp = (len > 0 && linebuffer[len - 1] == '\n');
-    }
-  else
-    vfprintf_maybe_filtered (stream, format, args, false);
+  vfprintf_maybe_filtered (stream, format, args, false);
 }
 
 void
-- 
2.31.1