OpenBSD-4.6/usr.bin/vi/vi/vs_relative.c
/* $OpenBSD: vs_relative.c,v 1.7 2008/03/08 12:34:09 otto Exp $ */
/*-
* Copyright (c) 1993, 1994
* The Regents of the University of California. All rights reserved.
* Copyright (c) 1993, 1994, 1995, 1996
* Keith Bostic. All rights reserved.
*
* See the LICENSE file for redistribution information.
*/
#include "config.h"
#ifndef lint
static const char sccsid[] = "@(#)vs_relative.c 10.11 (Berkeley) 5/13/96";
#endif /* not lint */
#include <sys/types.h>
#include <sys/queue.h>
#include <sys/time.h>
#include <bitstring.h>
#include <limits.h>
#include <stdio.h>
#include <string.h>
#include "../common/common.h"
#include "vi.h"
/*
* vs_column --
* Return the logical column of the cursor in the line.
*
* PUBLIC: int vs_column(SCR *, size_t *);
*/
int
vs_column(sp, colp)
SCR *sp;
size_t *colp;
{
VI_PRIVATE *vip;
vip = VIP(sp);
*colp = (O_ISSET(sp, O_LEFTRIGHT) ?
vip->sc_smap->coff : (vip->sc_smap->soff - 1) * sp->cols) +
vip->sc_col - (O_ISSET(sp, O_NUMBER) ? O_NUMBER_LENGTH : 0);
return (0);
}
/*
* vs_screens --
* Return the screens necessary to display the line, or if specified,
* the physical character column within the line, including space
* required for the O_NUMBER and O_LIST options.
*
* PUBLIC: size_t vs_screens(SCR *, recno_t, size_t *);
*/
size_t
vs_screens(sp, lno, cnop)
SCR *sp;
recno_t lno;
size_t *cnop;
{
size_t cols, screens;
/* Left-right screens are simple, it's always 1. */
if (O_ISSET(sp, O_LEFTRIGHT))
return (1);
/*
* Check for a cached value. We maintain a cache because, if the
* line is large, this routine gets called repeatedly. One other
* hack, lots of time the cursor is on column one, which is an easy
* one.
*/
if (cnop == NULL) {
if (VIP(sp)->ss_lno == lno)
return (VIP(sp)->ss_screens);
} else if (*cnop == 0)
return (1);
/* Figure out how many columns the line/column needs. */
cols = vs_columns(sp, NULL, lno, cnop, NULL);
screens = (cols / sp->cols + (cols % sp->cols ? 1 : 0));
if (screens == 0)
screens = 1;
/* Cache the value. */
if (cnop == NULL) {
VIP(sp)->ss_lno = lno;
VIP(sp)->ss_screens = screens;
}
return (screens);
}
/*
* vs_columns --
* Return the screen columns necessary to display the line, or,
* if specified, the physical character column within the line.
*
* PUBLIC: size_t vs_columns(SCR *, char *, recno_t, size_t *, size_t *);
*/
size_t
vs_columns(sp, lp, lno, cnop, diffp)
SCR *sp;
char *lp;
recno_t lno;
size_t *cnop, *diffp;
{
size_t chlen, cno, curoff, last, len, scno;
int ch, leftright, listset;
char *p;
/*
* Initialize the screen offset.
*/
scno = 0;
curoff = 0;
/* Leading number if O_NUMBER option set. */
if (O_ISSET(sp, O_NUMBER)) {
scno += O_NUMBER_LENGTH;
curoff += O_NUMBER_LENGTH;
}
/* Need the line to go any further. */
if (lp == NULL) {
(void)db_get(sp, lno, 0, &lp, &len);
if (len == 0)
goto done;
}
/* Missing or empty lines are easy. */
if (lp == NULL) {
done: if (diffp != NULL) /* XXX */
*diffp = 0;
return (scno);
}
/* Store away the values of the list and leftright edit options. */
listset = O_ISSET(sp, O_LIST);
leftright = O_ISSET(sp, O_LEFTRIGHT);
/*
* Initialize the pointer into the buffer.
*/
p = lp;
/* Macro to return the display length of any signal character. */
#define CHLEN(val) (ch = *(u_char *)p++) == '\t' && \
!listset ? TAB_OFF(val) : KEY_LEN(sp, ch);
/*
* If folding screens (the historic vi screen format), past the end
* of the current screen, and the character was a tab, reset the
* current screen column to 0, and the total screen columns to the
* last column of the screen. Otherwise, display the rest of the
* character in the next screen.
*/
#define TAB_RESET { \
curoff += chlen; \
if (!leftright && curoff >= sp->cols) { \
if (ch == '\t') { \
curoff = 0; \
scno -= scno % sp->cols; \
} else \
curoff -= sp->cols; \
} \
}
if (cnop == NULL)
while (len--) {
chlen = CHLEN(curoff);
last = scno;
scno += chlen;
TAB_RESET;
}
else
for (cno = *cnop;; --cno) {
chlen = CHLEN(curoff);
last = scno;
scno += chlen;
TAB_RESET;
if (cno == 0)
break;
}
/* Add the trailing '$' if the O_LIST option set. */
if (listset && cnop == NULL)
scno += KEY_LEN(sp, '$');
/*
* The text input screen code needs to know how much additional
* room the last two characters required, so that it can handle
* tab character displays correctly.
*/
if (diffp != NULL)
*diffp = scno - last;
return (scno);
}
/*
* vs_rcm --
* Return the physical column from the line that will display a
* character closest to the currently most attractive character
* position (which is stored as a screen column).
*
* PUBLIC: size_t vs_rcm(SCR *, recno_t, int);
*/
size_t
vs_rcm(sp, lno, islast)
SCR *sp;
recno_t lno;
int islast;
{
size_t len;
/* Last character is easy, and common. */
if (islast) {
if (db_get(sp, lno, 0, NULL, &len) || len == 0)
return (0);
return (len - 1);
}
/* First character is easy, and common. */
if (sp->rcm == 0)
return (0);
return (vs_colpos(sp, lno, sp->rcm));
}
/*
* vs_colpos --
* Return the physical column from the line that will display a
* character closest to the specified screen column.
*
* PUBLIC: size_t vs_colpos(SCR *, recno_t, size_t);
*/
size_t
vs_colpos(sp, lno, cno)
SCR *sp;
recno_t lno;
size_t cno;
{
size_t chlen, curoff, len, llen, off, scno;
int ch, leftright, listset;
char *lp, *p;
/* Need the line to go any further. */
(void)db_get(sp, lno, 0, &lp, &llen);
/* Missing or empty lines are easy. */
if (lp == NULL || llen == 0)
return (0);
/* Store away the values of the list and leftright edit options. */
listset = O_ISSET(sp, O_LIST);
leftright = O_ISSET(sp, O_LEFTRIGHT);
/* Discard screen (logical) lines. */
off = cno / sp->cols;
cno %= sp->cols;
for (scno = 0, p = lp, len = llen; off--;) {
for (; len && scno < sp->cols; --len)
scno += CHLEN(scno);
/*
* If reached the end of the physical line, return the last
* physical character in the line.
*/
if (len == 0)
return (llen - 1);
/*
* If folding screens (the historic vi screen format), past
* the end of the current screen, and the character was a tab,
* reset the current screen column to 0. Otherwise, the rest
* of the character is displayed in the next screen.
*/
if (leftright && ch == '\t')
scno = 0;
else
scno -= sp->cols;
}
/* Step through the line until reach the right character or EOL. */
for (curoff = scno; len--;) {
chlen = CHLEN(curoff);
/*
* If we've reached the specific character, there are three
* cases.
*
* 1: scno == cno, i.e. the current character ends at the
* screen character we care about.
* a: off < llen - 1, i.e. not the last character in
* the line, return the offset of the next character.
* b: else return the offset of the last character.
* 2: scno != cno, i.e. this character overruns the character
* we care about, return the offset of this character.
*/
if ((scno += chlen) >= cno) {
off = p - lp;
return (scno == cno ?
(off < llen - 1 ? off : llen - 1) : off - 1);
}
TAB_RESET;
}
/* No such character; return the start of the last character. */
return (llen - 1);
}