1 files changed, 365 insertions, 0 deletions
diff --git a/lib/readline/undo.c b/lib/readline/undo.c
new file mode 100644
index 0000000..ae65d38
--- /dev/null
+++ b/lib/readline/undo.c
@@ -0,0 +1,365 @@
+/* undo.c - manage list of changes to lines, offering opportunity to undo them */
+
+/* Copyright (C) 1987-2017 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.      
+
+   Readline 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 3 of the License, or
+   (at your option) any later version.
+
+   Readline 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 Readline.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#define READLINE_LIBRARY
+
+#if defined (HAVE_CONFIG_H)
+#  include <config.h>
+#endif
+
+#include <sys/types.h>
+
+#if defined (HAVE_UNISTD_H)
+#  include <unistd.h>           /* for _POSIX_VERSION */
+#endif /* HAVE_UNISTD_H */
+
+#if defined (HAVE_STDLIB_H)
+#  include <stdlib.h>
+#else
+#  include "ansi_stdlib.h"
+#endif /* HAVE_STDLIB_H */
+
+#include <stdio.h>
+
+/* System-specific feature definitions and include files. */
+#include "rldefs.h"
+
+/* Some standard library routines. */
+#include "readline.h"
+#include "history.h"
+
+#include "rlprivate.h"
+#include "xmalloc.h"
+
+extern void _hs_replace_history_data PARAMS((int, histdata_t *, histdata_t *));
+
+extern HIST_ENTRY *_rl_saved_line_for_history;
+
+/* Non-zero tells rl_delete_text and rl_insert_text to not add to
+   the undo list. */
+int _rl_doing_an_undo = 0;
+
+/* How many unclosed undo groups we currently have. */
+int _rl_undo_group_level = 0;
+
+/* The current undo list for THE_LINE. */
+UNDO_LIST *rl_undo_list = (UNDO_LIST *)NULL;
+
+/* **************************************************************** */
+/*								    */
+/*			Undo, and Undoing			    */
+/*								    */
+/* **************************************************************** */
+
+static UNDO_LIST *
+alloc_undo_entry (enum undo_code what, int start, int end, char *text)
+{
+  UNDO_LIST *temp;
+
+  temp = (UNDO_LIST *)xmalloc (sizeof (UNDO_LIST));
+  temp->what = what;
+  temp->start = start;
+  temp->end = end;
+  temp->text = text;
+
+  temp->next = (UNDO_LIST *)NULL;
+  return temp;
+}
+
+/* Remember how to undo something.  Concatenate some undos if that
+   seems right. */
+void
+rl_add_undo (enum undo_code what, int start, int end, char *text)
+{
+  UNDO_LIST *temp;
+
+  temp = alloc_undo_entry (what, start, end, text);
+  temp->next = rl_undo_list;
+  rl_undo_list = temp;
+}
+
+/* Free an UNDO_LIST */
+void
+_rl_free_undo_list (UNDO_LIST *ul)
+{
+  UNDO_LIST *release;
+
+  while (ul)
+    {
+      release = ul;
+      ul = ul->next;
+
+      if (release->what == UNDO_DELETE)
+	xfree (release->text);
+
+      xfree (release);
+    }
+}
+
+/* Free the existing undo list. */
+void
+rl_free_undo_list (void)
+{
+  UNDO_LIST *release, *orig_list;
+
+  orig_list = rl_undo_list;
+  _rl_free_undo_list (rl_undo_list);
+  rl_undo_list = (UNDO_LIST *)NULL;
+  _hs_replace_history_data (-1, (histdata_t *)orig_list, (histdata_t *)NULL);
+}
+
+UNDO_LIST *
+_rl_copy_undo_entry (UNDO_LIST *entry)
+{
+  UNDO_LIST *new;
+
+  new = alloc_undo_entry (entry->what, entry->start, entry->end, (char *)NULL);
+  new->text = entry->text ? savestring (entry->text) : 0;
+  return new;
+}
+
+UNDO_LIST *
+_rl_copy_undo_list (UNDO_LIST *head)
+{
+  UNDO_LIST *list, *new, *roving, *c;
+
+  if (head == 0)
+    return head;
+
+  list = head;
+  new = 0;
+  while (list)
+    {
+      c = _rl_copy_undo_entry (list);
+      if (new == 0)
+	roving = new = c;
+      else
+	{
+	  roving->next = c;
+	  roving = roving->next;
+	}
+      list = list->next;
+    }
+
+  roving->next = 0;
+  return new;
+}
+
+/* Undo the next thing in the list.  Return 0 if there
+   is nothing to undo, or non-zero if there was. */
+int
+rl_do_undo (void)
+{
+  UNDO_LIST *release, *search;
+  int waiting_for_begin, start, end;
+  HIST_ENTRY *cur, *temp;
+
+#define TRANS(i) ((i) == -1 ? rl_point : ((i) == -2 ? rl_end : (i)))
+
+  start = end = waiting_for_begin = 0;
+  do
+    {
+      if (rl_undo_list == 0)
+	return (0);
+
+      _rl_doing_an_undo = 1;
+      RL_SETSTATE(RL_STATE_UNDOING);
+
+      /* To better support vi-mode, a start or end value of -1 means
+	 rl_point, and a value of -2 means rl_end. */
+      if (rl_undo_list->what == UNDO_DELETE || rl_undo_list->what == UNDO_INSERT)
+	{
+	  start = TRANS (rl_undo_list->start);
+	  end = TRANS (rl_undo_list->end);
+	}
+
+      switch (rl_undo_list->what)
+	{
+	/* Undoing deletes means inserting some text. */
+	case UNDO_DELETE:
+	  rl_point = start;
+	  rl_insert_text (rl_undo_list->text);
+	  xfree (rl_undo_list->text);
+	  break;
+
+	/* Undoing inserts means deleting some text. */
+	case UNDO_INSERT:
+	  rl_delete_text (start, end);
+	  rl_point = start;
+	  break;
+
+	/* Undoing an END means undoing everything 'til we get to a BEGIN. */
+	case UNDO_END:
+	  waiting_for_begin++;
+	  break;
+
+	/* Undoing a BEGIN means that we are done with this group. */
+	case UNDO_BEGIN:
+	  if (waiting_for_begin)
+	    waiting_for_begin--;
+	  else
+	    rl_ding ();
+	  break;
+	}
+
+      _rl_doing_an_undo = 0;
+      RL_UNSETSTATE(RL_STATE_UNDOING);
+
+      release = rl_undo_list;
+      rl_undo_list = rl_undo_list->next;
+      release->next = 0;	/* XXX */
+
+      /* If we are editing a history entry, make sure the change is replicated
+	 in the history entry's line */
+      cur = current_history ();
+      if (cur && cur->data && (UNDO_LIST *)cur->data == release)
+	{
+	  temp = replace_history_entry (where_history (), rl_line_buffer, (histdata_t)rl_undo_list);
+	  xfree (temp->line);
+	  FREE (temp->timestamp);
+	  xfree (temp);
+	}
+
+      /* Make sure there aren't any history entries with that undo list */
+      _hs_replace_history_data (-1, (histdata_t *)release, (histdata_t *)rl_undo_list);
+
+      /* And make sure this list isn't anywhere in the saved line for history */
+      if (_rl_saved_line_for_history && _rl_saved_line_for_history->data)
+	{
+	  /* Brute force; no finesse here */
+	  search = (UNDO_LIST *)_rl_saved_line_for_history->data;
+	  if (search == release)
+	    _rl_saved_line_for_history->data = rl_undo_list;
+	  else
+	    {
+	      while (search->next)
+		{
+		  if (search->next == release)
+		    {
+		      search->next = rl_undo_list;
+		      break;
+		    }
+		  search = search->next;
+		}
+	    }
+	}
+
+      xfree (release);
+    }
+  while (waiting_for_begin);
+
+  return (1);
+}
+#undef TRANS
+
+int
+_rl_fix_last_undo_of_type (int type, int start, int end)
+{
+  UNDO_LIST *rl;
+
+  for (rl = rl_undo_list; rl; rl = rl->next)
+    {
+      if (rl->what == type)
+	{
+	  rl->start = start;
+	  rl->end = end;
+	  return 0;
+	}
+    }
+  return 1;
+}
+
+/* Begin a group.  Subsequent undos are undone as an atomic operation. */
+int
+rl_begin_undo_group (void)
+{
+  rl_add_undo (UNDO_BEGIN, 0, 0, 0);
+  _rl_undo_group_level++;
+  return 0;
+}
+
+/* End an undo group started with rl_begin_undo_group (). */
+int
+rl_end_undo_group (void)
+{
+  rl_add_undo (UNDO_END, 0, 0, 0);
+  _rl_undo_group_level--;
+  return 0;
+}
+
+/* Save an undo entry for the text from START to END. */
+int
+rl_modifying (int start, int end)
+{
+  if (start > end)
+    {
+      SWAP (start, end);
+    }
+
+  if (start != end)
+    {
+      char *temp = rl_copy_text (start, end);
+      rl_begin_undo_group ();
+      rl_add_undo (UNDO_DELETE, start, end, temp);
+      rl_add_undo (UNDO_INSERT, start, end, (char *)NULL);
+      rl_end_undo_group ();
+    }
+  return 0;
+}
+
+/* Revert the current line to its previous state. */
+int
+rl_revert_line (int count, int key)
+{
+  if (rl_undo_list == 0)
+    rl_ding ();
+  else
+    {
+      while (rl_undo_list)
+	rl_do_undo ();
+#if defined (VI_MODE)
+      if (rl_editing_mode == vi_mode)
+	rl_point = rl_mark = 0;		/* rl_end should be set correctly */
+#endif
+    }
+    
+  return 0;
+}
+
+/* Do some undoing of things that were done. */
+int
+rl_undo_command (int count, int key)
+{
+  if (count < 0)
+    return 0;	/* Nothing to do. */
+
+  while (count)
+    {
+      if (rl_do_undo ())
+	count--;
+      else
+	{
+	  rl_ding ();
+	  break;
+	}
+    }
+  return 0;
+}