Show undo.c syntax highlighted
/* readline.c -- a general facility for reading lines of input
with emacs style editing and completion. */
/* Copyright (C) 1987, 1989, 1992 Free Software Foundation, Inc.
This file is part of the GNU Readline Library, a library for
reading lines of text with interactive input and history editing.
The GNU Readline Library 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, or
(at your option) any later version.
The GNU Readline Library 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.
The GNU General Public License is often shipped with GNU software, and
is generally kept in a file called COPYING or LICENSE. If you do not
have a copy of the license, write to the Free Software Foundation,
59 Temple Place, Suite 330, Boston, MA 02111 USA. */
#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"
/* 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 */
/* */
/* **************************************************************** */
/* Remember how to undo something. Concatenate some undos if that
seems right. */
void
rl_add_undo (what, start, end, text)
enum undo_code what;
int start, end;
char *text;
{
UNDO_LIST *temp = (UNDO_LIST *)xmalloc (sizeof (UNDO_LIST));
temp->what = what;
temp->start = start;
temp->end = end;
temp->text = text;
temp->next = rl_undo_list;
rl_undo_list = temp;
}
/* Free the existing undo list. */
void
rl_free_undo_list ()
{
while (rl_undo_list)
{
UNDO_LIST *release = rl_undo_list;
rl_undo_list = rl_undo_list->next;
if (release->what == UNDO_DELETE)
free (release->text);
free (release);
}
rl_undo_list = (UNDO_LIST *)NULL;
}
/* 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 ()
{
UNDO_LIST *release;
int waiting_for_begin, start, end;
#define TRANS(i) ((i) == -1 ? rl_point : ((i) == -2 ? rl_end : (i)))
start = end = waiting_for_begin = 0;
do
{
if (!rl_undo_list)
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);
free (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;
free (release);
}
while (waiting_for_begin);
return (1);
}
#undef TRANS
int
_rl_fix_last_undo_of_type (type, start, end)
int type, start, 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 ()
{
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 ()
{
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 (start, end)
int start, 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 (count, key)
int count, key;
{
if (!rl_undo_list)
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 (count, key)
int count, key;
{
if (count < 0)
return 0; /* Nothing to do. */
while (count)
{
if (rl_do_undo ())
count--;
else
{
rl_ding ();
break;
}
}
return 0;
}
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