Re: [RFA]: Tui hooks and tui-out

[Stephane Carrez <Stephane dot Carrez at worldnet dot fr>]

Hi!

Andrew Cagney a écrit :
> 
> > Hi!
> >
> > The following patch contains two new files to replace the old tui hacks
> > and use the existing gdb support:
> >
> >  - the tui-hooks.c file defines several hooks (those used by Insight),
> >    that are installed in tui-curses mode.  Most of them are un-installed
> >    when we leave the curses-mode (and switch to gdb-default stdout mode).
> >
> >  - the tui-out.c file is a specific ui-out, modeled on cli-out.c
> >    (copied and sed s/cli_/tui_/).  It catches several fields to identify
> >    the source line and file name.  The catching implementation is very
> >    crude, needs to be improved, but works enough for tui interface.
> >
> > Do you agree with this?
> >
> >       Stephane
> >
> > 2001-07-17  Stephane Carrez  <Stephane.Carrez@worldnet.fr>
> >
> > * tui-hooks.c: New file, gdb hooks for tui.
> 
> FYI, GDB is moving away from ``hooks'' and towards gdb-events.  It is
> ment to eventually be an observer so that the TUI and anything else can
> monitor what GDB is up to.
> 
> Where there is a choice between a hook and a gdb-event, can you please
> use the latter.

Ok.  I wasn't sure whether gdb-event was usable or not.  It looks better.
I switched all the breakpoint hooks to use that.

> 
> >       * tui-out.c: New file, image copied from cli-out.c.
> >       (tui_field_int): Identify "line" fields and keep track of them.
> >       (tui_field_string): Likewise for "file".
> >       (tui_out_new): Use flags = 0 to avoid printing the sources.
> 
> This is ok.
> 
> I guess you're using that to capture the stop source-and-line.  The
> model is going to be changed.  Instead:
> 
>         o       gdb-events notifies observers that
>                 the target has stopped
> 
>         o       the TUI (an observer) queries GDB for
>                 all relevant stop information
> 
> it should stop false source-and-line detection.  Your code will still be
> used, just slightly differently.
> 
>         Andrew

It looks reasonable and probably better for some long-term architecture.

Here is the new patch (tui-hooks.c only) that uses the gdb-events.

	Stephane
Index: tui-hooks.c
===================================================================
RCS file: tui-hooks.c
diff -N tui-hooks.c
--- /dev/null	Tue May  5 13:32:27 1998
+++ tui-hooks.c	Thu Jul 19 15:00:52 2001
@@ -0,0 +1,390 @@
+/* GDB hooks for TUI.
+   Copyright 2001 Free Software Foundation, Inc.
+
+   This file is part of GDB.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include "defs.h"
+#include "symtab.h"
+#include "inferior.h"
+#include "command.h"
+#include "bfd.h"
+#include "symfile.h"
+#include "objfiles.h"
+#include "target.h"
+#include "gdbcore.h"
+#include "event-loop.h"
+#include "frame.h"
+#include "breakpoint.h"
+#include "gdb-events.h"
+#include <unistd.h>
+#include <fcntl.h>
+
+#include "tui.h"
+#include "tuiData.h"
+#include "tuiLayout.h"
+#include "tuiIO.h"
+#include "tuiRegs.h"
+#include "tuiWin.h"
+#include "tuiStack.h"
+#include "tuiDataWin.h"
+#include "tuiSourceWin.h"
+
+int tui_target_has_run = 0;
+
+static void (* tui_target_new_objfile_chain) (struct objfile*);
+extern void (*selected_frame_level_changed_hook) (int);
+
+static void
+tui_new_objfile_hook (struct objfile* objfile)
+{
+  if (tui_active)
+    {
+      tuiDisplayMainFunction ();
+    }
+  
+  if (tui_target_new_objfile_chain)
+    tui_target_new_objfile_chain (objfile);
+}
+
+static int
+tui_query_hook (const char * msg, va_list argp)
+{
+  int retval;
+  int ans2;
+  int answer;
+
+  /* Automatically answer "yes" if input is not from a terminal.  */
+  if (!input_from_terminal_p ())
+    return 1;
+
+  echo ();
+  while (1)
+    {
+      wrap_here ("");		/* Flush any buffered output */
+      gdb_flush (gdb_stdout);
+
+      vfprintf_filtered (gdb_stdout, msg, argp);
+      printf_filtered ("(y or n) ");
+
+      wrap_here ("");
+      gdb_flush (gdb_stdout);
+
+      answer = tui_getc (stdin);
+      clearerr (stdin);		/* in case of C-d */
+      if (answer == EOF)	/* C-d */
+	{
+	  retval = 1;
+	  break;
+	}
+      /* Eat rest of input line, to EOF or newline */
+      if (answer != '\n')
+	do
+	  {
+            ans2 = tui_getc (stdin);
+	    clearerr (stdin);
+	  }
+	while (ans2 != EOF && ans2 != '\n' && ans2 != '\r');
+
+      if (answer >= 'a')
+	answer -= 040;
+      if (answer == 'Y')
+	{
+	  retval = 1;
+	  break;
+	}
+      if (answer == 'N')
+	{
+	  retval = 0;
+	  break;
+	}
+      printf_filtered ("Please answer y or n.\n");
+    }
+  noecho ();
+  return retval;
+}
+
+/* Prevent recursion of registers_changed_hook().  */
+static int tui_refreshing_registers = 0;
+
+static void
+tui_registers_changed_hook (void)
+{
+  struct frame_info *fi;
+
+  fi = selected_frame;
+  if (fi && tui_refreshing_registers == 0)
+    {
+      tui_refreshing_registers = 1;
+#if 0
+      tuiCheckDataValues (fi);
+#endif
+      tui_refreshing_registers = 0;
+    }
+}
+
+static void
+tui_register_changed_hook (int regno)
+{
+  struct frame_info *fi;
+
+  fi = selected_frame;
+  if (fi && tui_refreshing_registers == 0)
+    {
+      tui_refreshing_registers = 1;
+      tuiCheckDataValues (fi);
+      tui_refreshing_registers = 0;
+    }
+}
+
+extern struct breakpoint *breakpoint_chain;
+
+/* Find a breakpoint given its number.  Returns null if not found.  */
+static struct breakpoint *
+get_breakpoint (int number)
+{
+  struct breakpoint *bp;
+
+  for (bp = breakpoint_chain; bp; bp = bp->next)
+    {
+      if (bp->number == number)
+        return bp;
+    }
+  return 0;
+}
+
+/* Breakpoint creation hook.
+   Update the screen to show the new breakpoint.  */
+static void
+tui_event_create_breakpoint (int number)
+{
+  struct breakpoint *bp;
+
+  bp = get_breakpoint (number);
+  if (bp)
+    {
+      switch (bp->type)
+        {
+        case bp_breakpoint:
+        case bp_hardware_breakpoint:
+          tuiAllSetHasBreakAt (bp, 1);
+          tuiUpdateAllExecInfos ();
+          break;
+
+        default:
+          break;
+        }
+    }
+}
+
+/* Breakpoint deletion hook.
+   Refresh the screen to update the breakpoint marks.  */
+static void
+tui_event_delete_breakpoint (int number)
+{
+  struct breakpoint *bp;
+  struct breakpoint *b;
+  int clearIt;
+
+  bp = get_breakpoint (number);
+  if (bp == 0)
+    return;
+
+  /* Before turning off the visuals for the bp, check to see that
+     there are no other bps at the same address. */
+  clearIt = 0;
+  for (b = breakpoint_chain; b; b = b->next)
+    {
+      clearIt = (b == bp || b->address != bp->address);
+      if (!clearIt)
+        break;
+    }
+
+  if (clearIt)
+    {
+      tuiAllSetHasBreakAt (bp, 0);
+      tuiUpdateAllExecInfos ();
+    }
+}
+
+static void
+tui_event_modify_breakpoint (int number)
+{
+  ;
+}
+
+static void
+tui_event_default (int number)
+{
+  ;
+}
+
+static struct gdb_events *tui_old_event_hooks;
+
+static struct gdb_events tui_event_hooks =
+{
+  tui_event_create_breakpoint,
+  tui_event_delete_breakpoint,
+  tui_event_modify_breakpoint,
+  tui_event_default,
+  tui_event_default,
+  tui_event_default
+};
+
+/* Called when going to wait for the target.
+   Leave curses mode and setup program mode.  */
+static ptid_t
+tui_target_wait_hook (ptid_t pid, struct target_waitstatus *status)
+{
+  ptid_t res;
+
+  /* Leave tui mode (optional).  */
+#if 0
+  if (tui_active)
+    {
+      target_terminal_ours ();
+      endwin ();
+      target_terminal_inferior ();
+    }
+#endif
+  tui_target_has_run = 1;
+  res = target_wait (pid, status);
+
+  if (tui_active)
+    {
+      /* TODO: need to refresh (optional).  */
+    }
+  return res;
+}
+
+/* The selected frame has changed.  This is happens after a target
+   stop or when the user explicitly changes the frame (up/down/thread/...).  */
+static void
+tui_selected_frame_level_changed_hook (int level)
+{
+  struct frame_info *fi;
+
+  fi = selected_frame;
+  /* Ensure that symbols for this frame are read in.  Also, determine the
+     source language of this frame, and switch to it if desired.  */
+  if (fi)
+    {
+      struct symtab *s;
+      
+      s = find_pc_symtab (fi->pc);
+      /* elz: this if here fixes the problem with the pc not being displayed
+         in the tui asm layout, with no debug symbols. The value of s 
+         would be 0 here, and select_source_symtab would abort the
+         command by calling the 'error' function */
+      if (s)
+	{
+          select_source_symtab (s);
+          tuiShowFrameInfo (fi);
+	}
+
+      /* Refresh the register window if it's visible.  */
+      if (tui_is_window_visible (DATA_WIN))
+        {
+          tui_refreshing_registers = 1;
+          tuiCheckDataValues (fi);
+          tui_refreshing_registers = 0;
+        }
+    }
+}
+
+/* Called from print_frame_info to list the line we stopped in.  */
+static void
+tui_print_frame_info_listing_hook (struct symtab *s, int line,
+                                   int stopline, int noerror)
+{
+  select_source_symtab (s);
+  tuiShowFrameInfo (selected_frame);
+}
+
+/* Install the TUI specific hooks.  */
+void
+tui_install_hooks (void)
+{
+  target_wait_hook = tui_target_wait_hook;
+  selected_frame_level_changed_hook = tui_selected_frame_level_changed_hook;
+  print_frame_info_listing_hook = tui_print_frame_info_listing_hook;
+
+  query_hook = tui_query_hook;
+
+  /* Install the event hooks.  */
+  tui_old_event_hooks = set_gdb_event_hooks (&tui_event_hooks);
+
+  registers_changed_hook = tui_registers_changed_hook;
+  register_changed_hook = tui_register_changed_hook;
+}
+
+/* Remove the TUI specific hooks.  */
+void
+tui_remove_hooks (void)
+{
+  target_wait_hook = 0;
+  selected_frame_level_changed_hook = 0;
+  print_frame_info_listing_hook = 0;
+  query_hook = 0;
+  registers_changed_hook = 0;
+  register_changed_hook = 0;
+
+  /* Restore the previous event hooks.  */
+  set_gdb_event_hooks (tui_old_event_hooks);
+}
+
+/* Cleanup the tui before exiting.  */
+static void
+tui_exit (void)
+{
+  /* Disable the tui.  Curses mode is left leaving the screen
+     in a clean state (see endwin()).  */
+  tui_disable ();
+}
+
+/* Initialize the tui by installing several gdb hooks, initializing
+   the tui IO and preparing the readline with the kind binding.  */
+static void
+tui_init_hook (char *argv0)
+{
+  /* Install exit handler to leave the screen in a good shape.  */
+  atexit (tui_exit);
+
+  initializeStaticData ();
+
+  /* Install the permanent hooks.  */
+  tui_target_new_objfile_chain = target_new_objfile_hook;
+  target_new_objfile_hook = tui_new_objfile_hook;
+
+  tui_initialize_io ();
+  tui_initialize_readline ();
+
+  /* Decide in which mode to start using GDB (based on -tui).  */
+  if (tui_version)
+    {
+      tui_enable ();
+    }
+}
+
+/* Initialize the tui.  */
+void
+_initialize_tui (void)
+{
+  /* Setup initialization hook.  */
+  init_ui_hook = tui_init_hook;
+}
+