[unix-history] / usr / src / lib / libcurses / newwin.c

/*
* Copyright (c) 1981 Regents of the University of California.
* All rights reserved.
*
* %sccs.include.redist.c%
*/

#ifndef lint
static char sccsid[] = "@(#)newwin.c    5.6 (Berkeley) %G%";
#endif  /* not lint */

#include <curses.h>
#include <stdlib.h>

#undef  nl              /* Don't need it here, and it interferes. */

static WINDOW *makenew __P((int, int, int, int));

/*
* newwin --
*      Allocate space for and set up defaults for a new window.
*/
WINDOW *
newwin(num_lines, num_cols, begy, begx)
       int num_lines, num_cols, begy, begx;
{
       register WINDOW *win;
       register int by, bx, i, j, nl, nc;
       register char *sp;

       by = begy;
       bx = begx;
       nl = num_lines;
       nc = num_cols;

       if (nl == 0)
               nl = LINES - by;
       if (nc == 0)
               nc = COLS - bx;
       if ((win = makenew(nl, nc, by, bx)) == NULL)
               return (NULL);
       if ((win->_firstch = malloc(nl * sizeof(win->_firstch[0]))) == NULL) {
               free(win->_y);
               free(win);
               return (NULL);
       }
       if ((win->_lastch = malloc(nl * sizeof(win->_lastch[0]))) == NULL) {
               free(win->_y);
               free(win->_firstch);
               free(win);
               return (NULL);
       }
       win->_nextp = win;
       for (i = 0; i < nl; i++) {
               win->_firstch[i] = _NOCHANGE;
               win->_lastch[i] = _NOCHANGE;
       }
       for (i = 0; i < nl; i++)
               if ((win->_y[i] = malloc(nc * sizeof(win->_y[0]))) == NULL) {
                       for (j = 0; j < i; j++)
                               free(win->_y[j]);
                       free(win->_firstch);
                       free(win->_lastch);
                       free(win->_y);
                       free(win);
                       return (NULL);
               } else
                       for (sp = win->_y[i]; sp < win->_y[i] + nc;)
                               *sp++ = ' ';
       win->_ch_off = 0;
#ifdef DEBUG
       __TRACE("newwin: win->_ch_off = %d\n", win->_ch_off);
#endif
       return (win);
}

WINDOW *
subwin(orig, num_lines, num_cols, begy, begx)
       register WINDOW *orig;
       int num_lines, num_cols, begy, begx;
{
       register WINDOW *win;
       register int by, bx, nl, nc;

       by = begy;
       bx = begx;
       nl = num_lines;
       nc = num_cols;

       /* Make sure window fits inside the original one. */
#ifdef  DEBUG
       __TRACE("subwin: (%0.2o, %d, %d, %d, %d)\n", orig, nl, nc, by, bx);
#endif
       if (by < orig->_begy || bx < orig->_begx
           || by + nl > orig->_maxy + orig->_begy
           || bx + nc > orig->_maxx + orig->_begx)
               return (NULL);
       if (nl == 0)
               nl = orig->_maxy + orig->_begy - by;
       if (nc == 0)
               nc = orig->_maxx + orig->_begx - bx;
       if ((win = makenew(nl, nc, by, bx)) == NULL)
               return (NULL);
       win->_nextp = orig->_nextp;
       orig->_nextp = win;
       win->_orig = orig;
       __set_subwin(orig, win);
       return (win);
}

/*
* This code is shared with mvwin().
*/
void
__set_subwin(orig, win)
       register WINDOW *orig, *win;
{
       register int i, j, k;

       j = win->_begy - orig->_begy;
       k = win->_begx - orig->_begx;
       win->_ch_off = k;
#ifdef DEBUG
       __TRACE("__set_subwin: win->_ch_off = %d\n", win->_ch_off);
#endif
       win->_firstch = &orig->_firstch[j];
       win->_lastch = &orig->_lastch[j];
       for (i = 0; i < win->_maxy; i++, j++)
               win->_y[i] = &orig->_y[j][k];
}

/*
* makenew --
*      Set up a window buffer and returns a pointer to it.
*/
static WINDOW *
makenew(num_lines, num_cols, begy, begx)
       int num_lines, num_cols, begy, begx;
{
       register WINDOW *win;
       register int by, bx, nl, nc;

       by = begy;
       bx = begx;
       nl = num_lines;
       nc = num_cols;

#ifdef  DEBUG
       __TRACE("makenew: (%d, %d, %d, %d)\n", nl, nc, by, bx);
#endif
       if ((win = malloc(sizeof(*win))) == NULL)
               return (NULL);
#ifdef DEBUG
       __TRACE("makenew: nl = %d\n", nl);
#endif
       if ((win->_y = malloc(nl * sizeof(win->_y[0]))) == NULL) {
               free(win);
               return (NULL);
       }
#ifdef DEBUG
       __TRACE("makenew: nc = %d\n", nc);
#endif
       win->_cury = win->_curx = 0;
       win->_clear = 0;
       win->_maxy = nl;
       win->_maxx = nc;
       win->_begy = by;
       win->_begx = bx;
       win->_flags = 0;
       win->_scroll = win->_leave = 0;
       __swflags(win);
#ifdef DEBUG
       __TRACE("makenew: win->_clear = %d\n", win->_clear);
       __TRACE("makenew: win->_leave = %d\n", win->_leave);
       __TRACE("makenew: win->_scroll = %d\n", win->_scroll);
       __TRACE("makenew: win->_flags = %0.2o\n", win->_flags);
       __TRACE("makenew: win->_maxy = %d\n", win->_maxy);
       __TRACE("makenew: win->_maxx = %d\n", win->_maxx);
       __TRACE("makenew: win->_begy = %d\n", win->_begy);
       __TRACE("makenew: win->_begx = %d\n", win->_begx);
#endif
       return (win);
}

void
__swflags(win)
       register WINDOW *win;
{
       win->_flags &= ~(_ENDLINE | _FULLLINE | _FULLWIN | _SCROLLWIN);
       if (win->_begx + win->_maxx == COLS) {
               win->_flags |= _ENDLINE;
               if (win->_begx == 0) {
                       if (AL && DL)
                               win->_flags |= _FULLLINE;
                       if (win->_maxy == LINES && win->_begy == 0)
                               win->_flags |= _FULLWIN;
               }
               if (win->_begy + win->_maxy == LINES)
                       win->_flags |= _SCROLLWIN;
       }
}