/* $NetBSD: mark.c,v 1.4 2014/01/26 21:43:45 christos Exp $ */
/*-
* Copyright (c) 1992, 1993, 1994
* The Regents of the University of California. All rights reserved.
* Copyright (c) 1992, 1993, 1994, 1995, 1996
* Keith Bostic. All rights reserved.
*
* See the LICENSE file for redistribution information.
*/
/*
* Marks are maintained in a key sorted doubly linked list. We can't
* use arrays because we have no idea how big an index key could be.
* The underlying assumption is that users don't have more than, say,
* 10 marks at any one time, so this will be is fast enough.
*
* Marks are fixed, and modifications to the line don't update the mark's
* position in the line. This can be hard. If you add text to the line,
* place a mark in that text, undo the addition and use ` to move to the
* mark, the location will have disappeared. It's tempting to try to adjust
* the mark with the changes in the line, but this is hard to do, especially
* if we've given the line to v_ntext.c:v_ntext() for editing. Historic vi
* would move to the first non-blank on the line when the mark location was
* past the end of the line. This can be complicated by deleting to a mark
* that has disappeared using the ` command. Historic vi treated this as
* a line-mode motion and deleted the line. This implementation complains to
* the user.
*
* In historic vi, marks returned if the operation was undone, unless the
* mark had been subsequently reset. Tricky. This is hard to start with,
* but in the presence of repeated undo it gets nasty. When a line is
* deleted, we delete (and log) any marks on that line. An undo will create
* the mark. Any mark creations are noted as to whether the user created
* it or if it was created by an undo. The former cannot be reset by another
* undo, but the latter may.
*
* All of these routines translate ABSMARK2 to ABSMARK1. Setting either of
* the absolute mark locations sets both, so that "m'" and "m`" work like
* they, ah, for lack of a better word, "should".
*/
/*
* mark_init --
* Set up the marks.
*
* PUBLIC: int mark_init __P((SCR *, EXF *));
*/
int
mark_init(SCR *sp, EXF *ep)
{
/*
* !!!
* ep MAY NOT BE THE SAME AS sp->ep, DON'T USE THE LATTER.
*
* Set up the marks.
*/
LIST_INIT(&ep->marks);
return (0);
}
/*
* mark_end --
* Free up the marks.
*
* PUBLIC: int mark_end __P((SCR *, EXF *));
*/
int
mark_end(SCR *sp, EXF *ep)
{
LMARK *lmp;
/*
* !!!
* ep MAY NOT BE THE SAME AS sp->ep, DON'T USE THE LATTER.
*/
while ((lmp = LIST_FIRST(&ep->marks)) != NULL) {
LIST_REMOVE(lmp, q);
free(lmp);
}
return (0);
}
/*
* mark_get --
* Get the location referenced by a mark.
*
* PUBLIC: int mark_get __P((SCR *, ARG_CHAR_T, MARK *, mtype_t));
*/
int
mark_get(SCR *sp, ARG_CHAR_T key, MARK *mp, mtype_t mtype)
{
LMARK *lmp;
if (key == ABSMARK2)
key = ABSMARK1;
lmp = mark_find(sp, key);
if (lmp == NULL || (ARG_CHAR_T)lmp->name != key) {
msgq(sp, mtype, "017|Mark %s: not set", KEY_NAME(sp, key));
return (1);
}
if (F_ISSET(lmp, MARK_DELETED)) {
msgq(sp, mtype,
"018|Mark %s: the line was deleted", KEY_NAME(sp, key));
return (1);
}
/*
* !!!
* The absolute mark is initialized to lno 1/cno 0, and historically
* you could use it in an empty file. Make such a mark always work.
*/
if ((lmp->lno != 1 || lmp->cno != 0) && !db_exist(sp, lmp->lno)) {
msgq(sp, mtype,
"019|Mark %s: cursor position no longer exists",
KEY_NAME(sp, key));
return (1);
}
mp->lno = lmp->lno;
mp->cno = lmp->cno;
return (0);
}
/*
* mark_set --
* Set the location referenced by a mark.
*
* PUBLIC: int mark_set __P((SCR *, ARG_CHAR_T, MARK *, int));
*/
int
mark_set(SCR *sp, ARG_CHAR_T key, MARK *value, int userset)
{
LMARK *lmp, *lmt;
if (key == ABSMARK2)
key = ABSMARK1;
/*
* The rules are simple. If the user is setting a mark (if it's a
* new mark this is always true), it always happens. If not, it's
* an undo, and we set it if it's not already set or if it was set
* by a previous undo.
*/
lmp = mark_find(sp, key);
if (lmp == NULL || (ARG_CHAR_T)lmp->name != key) {
MALLOC_RET(sp, lmt, LMARK *, sizeof(LMARK));
if (lmp == NULL) {
LIST_INSERT_HEAD(&sp->ep->marks, lmt, q);
} else
LIST_INSERT_AFTER(lmp, lmt, q);
lmp = lmt;
} else if (!userset &&
!F_ISSET(lmp, MARK_DELETED) && F_ISSET(lmp, MARK_USERSET))
return (0);
/*
* mark_find --
* Find the requested mark, or, the slot immediately before
* where it would go.
*/
static LMARK *
mark_find(SCR *sp, ARG_CHAR_T key)
{
LMARK *lmp, *lastlmp;
/*
* Return the requested mark or the slot immediately before
* where it should go.
*/
for (lastlmp = NULL, lmp = LIST_FIRST(&sp->ep->marks);
lmp != NULL; lastlmp = lmp, lmp = LIST_NEXT(lmp, q))
if ((ARG_CHAR_T)lmp->name >= key)
return ((ARG_CHAR_T)lmp->name == key ? lmp : lastlmp);
return (lastlmp);
}
/*
* mark_insdel --
* Update the marks based on an insertion or deletion.
*
* PUBLIC: int mark_insdel __P((SCR *, lnop_t, db_recno_t));
*/
int
mark_insdel(SCR *sp, lnop_t op, db_recno_t lno)
{
LMARK *lmp;
db_recno_t lline;
switch (op) {
case LINE_APPEND:
/* All insert/append operations are done as inserts. */
abort();
case LINE_DELETE:
LIST_FOREACH(lmp, &sp->ep->marks, q)
if (lmp->lno >= lno) {
if (lmp->lno == lno) {
F_SET(lmp, MARK_DELETED);
(void)log_mark(sp, lmp);
} else
--lmp->lno;
}
break;
case LINE_INSERT:
/*
* XXX
* Very nasty special case. If the file was empty, then we're
* adding the first line, which is a replacement. So, we don't
* modify the marks. This is a hack to make:
*
* mz:r!echo foo<carriage-return>'z
*
* work, i.e. historically you could mark the "line" in an empty
* file and replace it, and continue to use the mark. Insane,
* well, yes, I know, but someone complained.
*
* Check for line #2 before going to the end of the file.
*/
if (!db_exist(sp, 2)) {
if (db_last(sp, &lline))
return (1);
if (lline == 1)
return (0);
}
LIST_FOREACH(lmp, &sp->ep->marks, q)
if (lmp->lno >= lno)
++lmp->lno;
break;
case LINE_RESET:
break;
}
return (0);
}
