svi_split.c

早期freebsd实现

/*-
 * Copyright (c) 1993, 1994
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#ifndef lint
static char sccsid[] = "@(#)svi_split.c	8.38 (Berkeley) 4/15/94";
#endif /* not lint */

#include <sys/types.h>
#include <sys/queue.h>
#include <sys/time.h>

#include <bitstring.h>
#include <errno.h>
#include <limits.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <termios.h>

#include "compat.h"
#include <curses.h>
#include <db.h>
#include <regex.h>

#include "vi.h"
#include "svi_screen.h"

/*
 * svi_split --
 *	Split the screen.
 */
int
svi_split(sp, argv)
	SCR *sp;
	ARGS *argv[];
{
	MSG *mp, *next;
	SCR *tsp, saved_sp;
	SVI_PRIVATE saved_svp;
	SMAP *smp;
	size_t cnt, half;
	int issmallscreen, splitup;

	/* Check to see if it's possible. */
	half = sp->rows / 2;
	if (half < MINIMUM_SCREEN_ROWS) {
		msgq(sp, M_ERR, "Screen must be larger than %d to split",
		     MINIMUM_SCREEN_ROWS);
		return (1);
	}

	/* Get a new screen. */
	if (screen_init(sp, &tsp, 0))
		return (1);
	CALLOC(sp, _HMAP(tsp), SMAP *, SIZE_HMAP(sp), sizeof(SMAP));
	if (_HMAP(tsp) == NULL)
		return (1);

	/*
	 * We're about to modify the current screen.  Save the contents
	 * in case something goes horribly, senselessly wrong.
	 */
	saved_sp = *sp;
	saved_svp = *SVP(sp);

/* INITIALIZED AT SCREEN CREATE. */

/* PARTIALLY OR COMPLETELY COPIED FROM PREVIOUS SCREEN. */
	/*
	 * Small screens: see svi/svi_refresh.c:svi_refresh, section 3b.
	 * Set a flag so we know to fix the screen up later.
	 */
	issmallscreen = ISSMALLSCREEN(sp);

	/*
	 * Split the screen, and link the screens together.  If the cursor
	 * is in the top half of the current screen, the new screen goes
	 * under the current screen.  Else, it goes above the current screen.
	 *
	 * The columns in the screen don't change.
	 */
	tsp->cols = sp->cols;

	cnt = svi_sm_cursor(sp, sp->ep, &smp) ? 0 : smp - HMAP;
	if (cnt <= half) {			/* Parent is top half. */
		/* Child. */
		tsp->rows = sp->rows - half;
		tsp->woff = sp->woff + half;
		tsp->t_maxrows = tsp->rows - 1;

		/* Parent. */
		sp->rows = half;
		sp->t_maxrows = sp->rows - 1;

		splitup = 0;
	} else {				/* Parent is bottom half. */
		/* Child. */
		tsp->rows = sp->rows - half;
		tsp->woff = sp->woff;
		tsp->t_maxrows = tsp->rows - 1;

		/* Parent. */
		sp->rows = half;
		sp->woff += tsp->rows;
		sp->t_maxrows = sp->rows - 1;

		/* Shift the parent's map down. */
		memmove(_HMAP(sp),
		    _HMAP(sp) + tsp->rows, sp->t_maxrows * sizeof(SMAP));

		splitup = 1;
	}

	/*
	 * Small screens: see svi/svi_refresh.c:svi_refresh, section 3b.
	 *
	 * The child may have different screen options sizes than the
	 * parent, so use them.  Make sure that the text counts aren't
	 * larger than the new screen sizes.
	 */
	if (issmallscreen) {
		/* Fix the text line count for the parent. */
		if (splitup)
			sp->t_rows -= tsp->rows;

		/* Fix the parent screen. */
		if (sp->t_rows > sp->t_maxrows)
			sp->t_rows = sp->t_maxrows;
		if (sp->t_minrows > sp->t_maxrows)
			sp->t_minrows = sp->t_maxrows;

		/* Fix the child screen. */
		tsp->t_minrows = tsp->t_rows = O_VAL(sp, O_WINDOW);
		if (tsp->t_rows > tsp->t_maxrows)
			tsp->t_rows = tsp->t_maxrows;
		if (tsp->t_minrows > tsp->t_maxrows)
			tsp->t_minrows = tsp->t_maxrows;

		/*
		 * If we split up, i.e. the child is on top, lines that
		 * were painted in the parent may not be painted in the
		 * child.  Clear any lines not being used in the child
		 * screen.
		 *
		 */
		if (splitup)
			for (cnt = tsp->t_rows; ++cnt <= tsp->t_maxrows;) {
				MOVE(tsp, cnt, 0);
				clrtoeol();
			}
	} else {
		sp->t_minrows = sp->t_rows = sp->rows - 1;

		/*
		 * The new screen may be a small screen, even though the
		 * parent was not.  Don't complain if O_WINDOW is too large,
		 * we're splitting the screen so the screen is much smaller
		 * than normal.  Clear any lines not being used in the child
		 * screen.
		 */
		tsp->t_minrows = tsp->t_rows = O_VAL(sp, O_WINDOW);
		if (tsp->t_rows > tsp->rows - 1)
			tsp->t_minrows = tsp->t_rows = tsp->rows - 1;
		else
			for (cnt = tsp->t_rows; ++cnt <= tsp->t_maxrows;) {
				MOVE(tsp, cnt, 0);
				clrtoeol();
			}
	}

	/* Adjust the ends of both maps. */
	_TMAP(sp) = _HMAP(sp) + (sp->t_rows - 1);
	_TMAP(tsp) = _HMAP(tsp) + (tsp->t_rows - 1);

	/*
	 * In any case, if the size of the scrolling region hasn't been
	 * modified by the user, reset it so it's reasonable for the split
	 * screen.
	 */
	if (!F_ISSET(&sp->opts[O_SCROLL], OPT_SET)) {
		O_VAL(sp, O_SCROLL) = sp->t_maxrows / 2;
		O_VAL(tsp, O_SCROLL) = sp->t_maxrows / 2;
	}

	/*
	 * If files specified, build the file list, else, link to the
	 * current file.
	 */
	if (argv == NULL) {
		if (file_add(tsp, NULL, FILENAME(sp->frp), 0) == NULL)
			goto err;
	} else
		for (; (*argv)->len != 0; ++argv)
			if (file_add(tsp, NULL, (*argv)->bp, 0) == NULL)
				goto err;

	/* Set up the argument and current FREF pointers. */
	if ((tsp->frp = file_first(tsp)) == NULL) {
		msgq(sp, M_ERR, "No files in the file list.");
		goto err;
	}

	tsp->a_frp = tsp->frp;

	/*
	 * Copy the file state flags, start the file.  Fill the child's
	 * screen map.  If the file is unchanged, keep the screen and
	 * cursor the same.
	 */
	if (argv == NULL) {
		tsp->ep = sp->ep;
		++sp->ep->refcnt;

		tsp->frp->flags = sp->frp->flags;
		tsp->frp->lno = sp->lno;
		tsp->frp->cno = sp->cno;
		F_SET(tsp->frp, FR_CURSORSET);

		/* Copy the parent's map into the child's map. */
		memmove(_HMAP(tsp), _HMAP(sp), tsp->t_rows * sizeof(SMAP));
	} else {
		if (file_init(tsp, tsp->frp, NULL, 0))
			goto err;
		(void)svi_sm_fill(tsp, tsp->ep, 1, P_TOP);
	}

	/* Everything's initialized, put the screen on the displayed queue.*/
	if (splitup) {
		/* Link in before the parent. */
		CIRCLEQ_INSERT_BEFORE(&sp->gp->dq, sp, tsp, q);
	} else {
		/* Link in after the parent. */
		CIRCLEQ_INSERT_AFTER(&sp->gp->dq, sp, tsp, q);
	}

	/* Clear the current information lines in both screens. */
	MOVE(sp, INFOLINE(sp), 0);
	clrtoeol();
	MOVE(tsp, INFOLINE(tsp), 0);
	clrtoeol();

	/* Redraw the status line for the parent screen. */
	(void)status(sp, sp->ep, sp->lno, 0);

	/* Save the parent screen's cursor information. */
	sp->frp->lno = sp->lno;
	sp->frp->cno = sp->cno;
	F_SET(sp->frp, FR_CURSORSET);

	/* Completely redraw the child screen. */
	F_SET(tsp, S_REDRAW);

	/* Switch screens. */
	sp->nextdisp = tsp;
	F_SET(sp, S_SSWITCH);
	return (0);

	/* Recover the original screen. */
err:	*sp = saved_sp;
	*SVP(sp) = saved_svp;

	/* Copy any (probably error) messages in the new screen. */
	for (mp = tsp->msgq.lh_first; mp != NULL; mp = next) {
		if (!F_ISSET(mp, M_EMPTY))
			msg_app(sp->gp, sp,
			    mp->flags & M_INV_VIDEO, mp->mbuf, mp->len);
		next = mp->q.le_next;
		if (mp->mbuf != NULL)
			free(mp->mbuf);
		free(mp);
	}

	/* Free the new screen. */
	free(_HMAP(tsp));