/* 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_fix_point (1);
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;
_rl_fix_point (1);
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;
}
FreeBSD-CVSweb <freebsd-cvsweb@FreeBSD.org>