Return to vs_relative.c CVS log

Up to [local] / src / usr.bin / vi / vi

rcsid[] and sccsid[] and copyright[] are essentially unmaintained (and
unmaintainable).  these days, people use source.  these id's do not provide
any benefit, and do hurt the small install media
(the 33,000 line diff is essentially mechanical)
ok with the idea millert, ok dms

/*	$OpenBSD: vs_relative.c,v 1.8 2009/10/27 23:59:49 deraadt 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"

#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);
}