OpenBSD-4.6/lib/libcurses/base/resizeterm.c

/*	$OpenBSD: resizeterm.c,v 1.2 2001/01/22 18:01:48 millert Exp $	*/

/****************************************************************************
 * Copyright (c) 1998,2000 Free Software Foundation, Inc.                   *
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 * copy of this software and associated documentation files (the            *
 * "Software"), to deal in the Software without restriction, including      *
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 * distribute, distribute with modifications, sublicense, and/or sell       *
 * copies of the Software, and to permit persons to whom the Software is    *
 * furnished to do so, subject to the following conditions:                 *
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 * in all copies or substantial portions of the Software.                   *
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 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF               *
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/****************************************************************************
 *  Author: Thomas E. Dickey <dickey@clark.net> 1996,1997                   *
 ****************************************************************************/

/*
 * This is an extension to the curses library.  It provides callers with a hook
 * into the NCURSES data to resize windows, primarily for use by programs
 * running in an X Window terminal (e.g., xterm).  I abstracted this module
 * from my application library for NCURSES because it must be compiled with
 * the private data structures -- T.Dickey 1995/7/4.
 */

#include <curses.priv.h>
#include <term.h>

MODULE_ID("$From: resizeterm.c,v 1.9 2000/12/10 02:43:28 tom Exp $")

/*
 * This function reallocates NCURSES window structures.  It is invoked in
 * response to a SIGWINCH interrupt.  Other user-defined windows may also need
 * to be reallocated.
 *
 * Because this performs memory allocation, it should not (in general) be
 * invoked directly from the signal handler.
 */
NCURSES_EXPORT(int)
resizeterm(int ToLines, int ToCols)
{
    int stolen = screen_lines - SP->_lines_avail;
    int bottom = screen_lines + SP->_topstolen - stolen;

    T((T_CALLED("resizeterm(%d,%d) old(%d,%d)"),
       ToLines, ToCols,
       screen_lines, screen_columns));

    SP->_sig_winch = FALSE;

    if (ToLines != screen_lines
	|| ToCols != screen_columns) {
	WINDOWLIST *wp;

#if USE_SIGWINCH
	ungetch(KEY_RESIZE);	/* so application can know this */
	clearok(curscr, TRUE);	/* screen contents are unknown */
#endif

	for (wp = _nc_windows; wp != 0; wp = wp->next) {
	    WINDOW *win = wp->win;
	    int myLines = win->_maxy + 1;
	    int myCols = win->_maxx + 1;

	    /* pads aren't treated this way */
	    if (win->_flags & _ISPAD)
		continue;

	    if (win->_begy >= bottom) {
		win->_begy += (ToLines - screen_lines);
	    } else {
		if (myLines == screen_lines - stolen
		    && ToLines != screen_lines)
		    myLines = ToLines - stolen;
		else if (myLines == screen_lines
			 && ToLines != screen_lines)
		    myLines = ToLines;
	    }

	    if (myCols == screen_columns
		&& ToCols != screen_columns)
		myCols = ToCols;

	    if (wresize(win, myLines, myCols) != OK)
		returnCode(ERR);
	}

	screen_lines = lines = ToLines;
	screen_columns = columns = ToCols;

	SP->_lines_avail = lines - stolen;

	if (SP->oldhash) {
	    FreeAndNull(SP->oldhash);
	}
	if (SP->newhash) {
	    FreeAndNull(SP->newhash);
	}
    }

    /*
     * Always update LINES, to allow for call from lib_doupdate.c which
     * needs to have the count adjusted by the stolen (ripped off) lines.
     */
    LINES = ToLines - stolen;
    COLS = ToCols;

    returnCode(OK);
}