xref: /src/lib/libcurses/resize.c

/*	$NetBSD: resize.c,v 1.35 2022/04/26 22:40:32 blymn Exp $	*/

/*
 * Copyright (c) 2001
 *	Brett Lymn.
 *
 * This code has been donated to The NetBSD Foundation by the Author.
 *
 * 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.
 *
 * 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.
 */

#include <sys/cdefs.h>
#ifndef lint
#if 0
static char sccsid[] = "@(#)resize.c   blymn 2001/08/26";
#else
__RCSID("$NetBSD: resize.c,v 1.35 2022/04/26 22:40:32 blymn Exp $");
#endif
#endif				/* not lint */

#include <stdlib.h>

#include "curses.h"
#include "curses_private.h"

static int __resizeterm(WINDOW *win, int nlines, int ncols);
static int __resizewin(WINDOW *win, int nlines, int ncols);

/*
 * wresize --
 *	Resize the given window to the new size.
 */
int
wresize(WINDOW *win, int req_nlines, int req_ncols)
{
	int	nlines = req_nlines;
	int	ncols = req_ncols;

	if (win == NULL)
		return ERR;

	__CTRACE(__CTRACE_WINDOW, "wresize: (%p, %d, %d)\n",
	    win, nlines, ncols);
	if (win->orig != NULL) {
		/* subwins must fit inside the parent - check this */
		if (win->begy > win->orig->begy + win->orig->maxy)
			win->begy = win->orig->begy + win->orig->maxy - 1;
		if (win->begy + nlines > win->orig->begy + win->orig->maxy)
			nlines = 0;
		if (nlines <= 0)
			nlines += win->orig->begy + win->orig->maxy - win->begy;
		if (nlines < 1)
			nlines = 1;
		if (win->begx > win->orig->begx + win->orig->maxx)
			win->begx = win->orig->begx + win->orig->maxx - 1;
		if (win->begx + ncols > win->orig->begx + win->orig->maxx)
			ncols = 0;
		if (ncols <= 0)
			ncols += win->orig->begx + win->orig->maxx - win->begx;
		if (ncols < 1)
			ncols = 1;
	} else if (!(win->flags & __ISPAD)) {
		/* bound "our" windows by the screen size */
		if (win == curscr || win == __virtscr || win == stdscr) {
			if (nlines > LINES)
				nlines = LINES;
			if (nlines < 1)
				nlines = 1;
			if (ncols > COLS)
				ncols = COLS;
			if (ncols < 1)
				ncols = 1;
		} else {
			if (win->begy > LINES)
				win->begy = 0;
			if (win->begy + nlines > LINES)
				nlines = 0;
			if (nlines <= 0)
				nlines += LINES - win->begy;
			if (nlines < 1)
				nlines = 1;
			if (win->begx > COLS)
				win->begx = 0;
			if (win->begx + ncols > COLS)
				ncols = 0;
			if (ncols <= 0)
				ncols += COLS - win->begx;
			if (ncols < 1)
				ncols = 1;
		}
	}

	if ((__resizewin(win, nlines, ncols)) == ERR)
		return ERR;

	win->reqy = req_nlines;
	win->reqx = req_ncols;

	/* If someone resizes curscr, we must also resize __virtscr */
	if (win == curscr) {
		if ((__resizewin(__virtscr, nlines, ncols)) == ERR)
			return ERR;
		__virtscr->reqy = req_nlines;
		__virtscr->reqx = req_ncols;
	}

	return OK;
}

/*
 * is_term_resized --
 *	Return true if the given dimensions do not match the
 *	internal structures.
 */
bool
is_term_resized(int nlines, int ncols)
{

	return (nlines > 0 && ncols > 0 &&
	    (nlines != _cursesi_screen->LINES ||
	    ncols != _cursesi_screen->COLS));
}

/*
 * resizeterm --
 *	Resize the terminal window, resizing the dependent windows.
 *	Handles internal book-keeping.
 */
int
resizeterm(int nlines, int ncols)
{
	int result;

	__CTRACE(__CTRACE_WINDOW, "resizeterm: (%d, %d)\n", nlines, ncols);

	/* Unconditionally inform application screen has been resized. */
	_cursesi_screen->resized = 1;

	if (!is_term_resized(nlines, ncols))
		return OK;

	result = resize_term(nlines, ncols);

	/* Screen contents are unknown, libcurses is not libpanel, we don't
	 * know the correct draw order. */
	clearok(curscr, TRUE);

	if (result == OK) {
		/* Redraw the soft label keys to the new size. */
		__slk_resize(_cursesi_screen, ncols);
		__slk_noutrefresh(_cursesi_screen);
	}

	return result;
}

/*
 * resize_term --
 *	Resize the terminal window, resizing the dependent windows.
 */
int
resize_term(int nlines, int ncols)
{
	WINDOW *win;
	struct __winlist *list;
	int rlines;

	__CTRACE(__CTRACE_WINDOW, "resize_term: (%d, %d)\n", nlines, ncols);

	if (!is_term_resized(nlines, ncols))
		return OK;

	if (__resizeterm(curscr, nlines, ncols) == ERR)
		return ERR;
	if (__resizeterm(__virtscr, nlines, ncols) == ERR)
		return ERR;
	rlines = nlines - __rippedlines(_cursesi_screen, 0);
	if (__resizeterm(stdscr, rlines, ncols) == ERR)
		return ERR;

	_cursesi_screen->LINES = nlines;
	_cursesi_screen->COLS = ncols;
	LINES = nlines;
	COLS = ncols;

	/* tweak the flags now that we have updated the LINES and COLS */
	for (list = _cursesi_screen->winlistp; list != NULL; list = list->nextp) {
		win = list->winp;

		if (!(win->flags & __ISPAD))
			__swflags(win);
	}

	/* Resize and re-position the ripped off windows. */
	if (__ripoffresize(_cursesi_screen) == ERR)
		return ERR;

	return OK;
}

/*
 * __resizeterm
 *	Setup window for resizing.
 */
static int
__resizeterm(WINDOW *win, int nlines, int ncols)
{
	int newlines, newcols;

	newlines = win->reqy;
	if (win->begy + newlines >= nlines)
		newlines = 0;
	if (newlines == 0)
		newlines = nlines - win->begy;

	newcols = win->reqx;
	if (win->begx + newcols >= ncols)
		newcols = 0;
	if (newcols == 0)
		newcols = ncols - win->begx;

	return __resizewin(win, newlines, newcols);
}

/*
 * __resizewin --
 *	Resize the given window.
 */
static int
__resizewin(WINDOW *win, int nlines, int ncols)
{
	__LINE			*lp, *olp, **newlines, *newlspace;
	__LDATA			*sp;
	__LDATA			*newwspace;
	int			 i, j;
	int			 y, x;
	WINDOW			*swin;

	__CTRACE(__CTRACE_WINDOW, "resize: (%p, %d, %d)\n", win, nlines, ncols);
	__CTRACE(__CTRACE_WINDOW, "resize: win->wattr = %08x\n", win->wattr);
	__CTRACE(__CTRACE_WINDOW, "resize: win->flags = %#.4x\n", win->flags);
	__CTRACE(__CTRACE_WINDOW, "resize: win->maxy = %d\n", win->maxy);
	__CTRACE(__CTRACE_WINDOW, "resize: win->maxx = %d\n", win->maxx);
	__CTRACE(__CTRACE_WINDOW, "resize: win->begy = %d\n", win->begy);
	__CTRACE(__CTRACE_WINDOW, "resize: win->begx = %d\n", win->begx);
	__CTRACE(__CTRACE_WINDOW, "resize: win->scr_t = %d\n", win->scr_t);
	__CTRACE(__CTRACE_WINDOW, "resize: win->scr_b = %d\n", win->scr_b);

	/*
	 * free up any non-spacing storage before we lose the
	 * pointers...
	 */
#ifdef HAVE_WCHAR
	__cursesi_win_free_nsp(win);
#endif

	if (nlines <= 0 || ncols <= 0)
		nlines = ncols = 0;
	else {
		/* Reallocate line pointer array and line space. */
		newlines = realloc(win->alines, nlines * sizeof(__LINE *));
		if (newlines == NULL)
			return ERR;
		win->alines = newlines;

		newlspace = realloc(win->lspace, nlines * sizeof(__LINE));
		if (newlspace == NULL)
			return ERR;
		win->lspace = newlspace;
	}

	/* Don't allocate window and line space if it's a subwindow */
	if (win->orig == NULL) {
		/*
		 * Allocate window space in one chunk.
		 */
		if (ncols != 0) {
			newwspace = realloc(win->wspace,
					    ncols * nlines * sizeof(__LDATA));
			if (newwspace == NULL)
				return ERR;
			win->wspace = newwspace;
		}

		/*
		 * Point line pointers to line space, and lines themselves into
		 * window space.
		 */
		for (lp = win->lspace, i = 0; i < nlines; i++, lp++) {
			win->alines[i] = lp;
			lp->line = &win->wspace[i * ncols];
#ifdef DEBUG
			lp->sentinel = SENTINEL_VALUE;
#endif
			lp->firstchp = &lp->firstch;
			lp->lastchp = &lp->lastch;
			lp->firstch = 0;
			lp->lastch = ncols - 1;
			lp->flags = __ISDIRTY;
		}
	} else {

		win->ch_off = win->begx - win->orig->begx;
		  /* Point line pointers to line space. */
		for (lp = win->lspace, i = 0; i < nlines; i++, lp++) {
			win->alines[i] = lp;
			olp = win->orig->alines[i + win->begy - win->orig->begy];
			lp->line = &olp->line[win->ch_off];
#ifdef DEBUG
			lp->sentinel = SENTINEL_VALUE;
#endif
			lp->firstchp = &olp->firstch;
			lp->lastchp = &olp->lastch;
			lp->flags = __ISDIRTY;
		}
	}

	win->cury = win->curx = 0;
	win->maxy = nlines;
	win->maxx = ncols;
	win->scr_b = win->maxy - 1;
	__swflags(win);

	  /*
	   * we must zot the window contents otherwise lines may pick
	   * up attributes from the previous line when the window is
	   * made smaller.  The client will redraw the window anyway
	   * so this is no big deal.
	   */
	for (i = 0; i < win->maxy; i++) {
		lp = win->alines[i];
		for (sp = lp->line, j = 0; j < win->maxx; j++, sp++) {
			sp->attr = 0;
#ifndef HAVE_WCHAR
			sp->ch = win->bch;
#else
			sp->ch = (wchar_t)btowc((int)win->bch);
			sp->nsp = NULL;
			if (_cursesi_copy_nsp(win->bnsp, sp) == ERR)
				return ERR;
			sp->wcols = 1;
#endif /* HAVE_WCHAR */
		}
		lp->hash = __hash_line(lp->line, ncols);
	}

	__CTRACE(__CTRACE_WINDOW, "resize: win->wattr = %08x\n", win->wattr);
	__CTRACE(__CTRACE_WINDOW, "resize: win->flags = %#.4x\n", win->flags);
	__CTRACE(__CTRACE_WINDOW, "resize: win->maxy = %d\n", win->maxy);
	__CTRACE(__CTRACE_WINDOW, "resize: win->maxx = %d\n", win->maxx);
	__CTRACE(__CTRACE_WINDOW, "resize: win->begy = %d\n", win->begy);
	__CTRACE(__CTRACE_WINDOW, "resize: win->begx = %d\n", win->begx);
	__CTRACE(__CTRACE_WINDOW, "resize: win->scr_t = %d\n", win->scr_t);
	__CTRACE(__CTRACE_WINDOW, "resize: win->scr_b = %d\n", win->scr_b);

	if (win->orig == NULL) {
		/* bound subwindows to new size and fixup their pointers */
		for (swin = win->nextp; swin != win; swin = swin->nextp) {
			y = swin->reqy;
			if (swin->begy > win->begy + win->maxy)
				swin->begy = win->begy + win->maxy - 1;
			if (swin->begy + y > win->begy + win->maxy)
				y = 0;
			if (y <= 0)
				y += win->begy + win->maxy - swin->begy;
			if (y < 1)
				y = 1;
			x = swin->reqx;
			if (swin->begx > win->begx + win->maxx)
				swin->begx = win->begx + win->maxx - 1;
			if (swin->begx + x > win->begx + win->maxx)
				x = 0;
			if (x <= 0)
				x += win->begx + win->maxx - swin->begx;
			if (x < 1)
				x = 1;
			__resizewin(swin, y, x);
		}
	}

	return OK;
}