Import readline 7.0 (patch 5)

This imports readline 7.0 (up to patch 5) while preserving all
gdb-local changes.

This was done by checking out the readline git repository, making a
branch based on the gdb baseline revision, applying the gdb changes to
that branch, and then merging from readline 7.

readline/ChangeLog.gdb
2019-08-12  Tom Tromey  <tom@tromey.com>

	* Imported readline 7.0 patch 5.

1 files changed, 40 insertions, 3 deletions

diff --git a/readline/misc.c b/readline/misc.c
index 9f45773..f7acdee 100644
--- a/readline/misc.c
+++ b/readline/misc.c
@@ -1,6 +1,6 @@
 /* misc.c -- miscellaneous bindable readline functions. */
 
-/* Copyright (C) 1987-2009 Free Software Foundation, Inc.
+/* Copyright (C) 1987-2015 Free Software Foundation, Inc.
 
    This file is part of the GNU Readline Library (Readline), a library
    for reading lines of text with interactive input and history editing.      
@@ -126,7 +126,7 @@ _rl_arg_dispatch (cxt, c)
 
   /* If we see a key bound to `universal-argument' after seeing digits,
       it ends the argument but is otherwise ignored. */
-  if (_rl_keymap[c].type == ISFUNC && _rl_keymap[c].function == rl_universal_argument)
+  if (c >= 0 && _rl_keymap[c].type == ISFUNC && _rl_keymap[c].function == rl_universal_argument)
     {
       if ((cxt & NUM_SAWDIGITS) == 0)
 	{
@@ -266,6 +266,8 @@ _rl_arg_callback (cxt)
   int c, r;
 
   c = _rl_arg_getchar ();
+  if (c < 0)
+    return (1);		/* EOF */
 
   if (_rl_argcxt & NUM_READONE)
     {
@@ -459,6 +461,7 @@ _rl_revert_all_lines ()
 	    saved_undo_list = 0;
 	  /* Set up rl_line_buffer and other variables from history entry */
 	  rl_replace_from_history (entry, 0);	/* entry->line is now current */
+	  entry->data = 0;			/* entry->data is now current undo list */
 	  /* Undo all changes to this history entry */
 	  while (rl_undo_list)
 	    rl_do_undo ();
@@ -466,7 +469,6 @@ _rl_revert_all_lines ()
 	     the timestamp. */
 	  FREE (entry->line);
 	  entry->line = savestring (rl_line_buffer);
-	  entry->data = 0;
 	}
       entry = previous_history ();
     }
@@ -483,6 +485,37 @@ _rl_revert_all_lines ()
   xfree (lbuf);
 }  
 
+/* Free the history list, including private readline data and take care
+   of pointer aliases to history data.  Resets rl_undo_list if it points
+   to an UNDO_LIST * saved as some history entry's data member.  This
+   should not be called while editing is active. */
+void
+rl_clear_history ()
+{
+  HIST_ENTRY **hlist, *hent;
+  register int i;
+  UNDO_LIST *ul, *saved_undo_list;
+
+  saved_undo_list = rl_undo_list;
+  hlist = history_list ();		/* direct pointer, not copy */
+
+  for (i = 0; i < history_length; i++)
+    {
+      hent = hlist[i];
+      if (ul = (UNDO_LIST *)hent->data)
+	{
+	  if (ul == saved_undo_list)
+	    saved_undo_list = 0;
+	  _rl_free_undo_list (ul);
+	  hent->data = 0;
+	}
+      _rl_free_history_entry (hent);
+    }
+
+  history_offset = history_length = 0;
+  rl_undo_list = saved_undo_list;	/* should be NULL */
+}
+
 /* **************************************************************** */
 /*								    */
 /*			History Commands			    */
@@ -623,6 +656,10 @@ rl_emacs_editing_mode (count, key)
   rl_editing_mode = emacs_mode;
   _rl_set_insert_mode (RL_IM_INSERT, 1); /* emacs mode default is insert mode */
   _rl_keymap = emacs_standard_keymap;
+
+  if (_rl_show_mode_in_prompt)
+    _rl_reset_prompt ();
+
   return 0;
 }