Base version of ncurses-5.7 library
diff --git a/ncurses/base/lib_pad.c b/ncurses/base/lib_pad.c
new file mode 100644
index 0000000..6cad9c5
--- /dev/null
+++ b/ncurses/base/lib_pad.c
@@ -0,0 +1,322 @@
+/****************************************************************************
+ * Copyright (c) 1998-2004,2006 Free Software Foundation, Inc.                   *
+ *                                                                          *
+ * Permission is hereby granted, free of charge, to any person obtaining a  *
+ * copy of this software and associated documentation files (the            *
+ * "Software"), to deal in the Software without restriction, including      *
+ * without limitation the rights to use, copy, modify, merge, publish,      *
+ * 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:                 *
+ *                                                                          *
+ * The above copyright notice and this permission notice shall be included  *
+ * in all copies or substantial portions of the Software.                   *
+ *                                                                          *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS  *
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF               *
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.   *
+ * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,   *
+ * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR    *
+ * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR    *
+ * THE USE OR OTHER DEALINGS IN THE SOFTWARE.                               *
+ *                                                                          *
+ * Except as contained in this notice, the name(s) of the above copyright   *
+ * holders shall not be used in advertising or otherwise to promote the     *
+ * sale, use or other dealings in this Software without prior written       *
+ * authorization.                                                           *
+ ****************************************************************************/
+
+/****************************************************************************
+ *  Author: Zeyd M. Ben-Halim <zmbenhal@netcom.com> 1992,1995               *
+ *     and: Eric S. Raymond <esr@snark.thyrsus.com>                         *
+ ****************************************************************************/
+
+/*
+ * lib_pad.c
+ * newpad	-- create a new pad
+ * pnoutrefresh -- refresh a pad, no update
+ * pechochar	-- add a char to a pad and refresh
+ */
+
+#include <curses.priv.h>
+
+MODULE_ID("$Id: lib_pad.c,v 1.41 2006/10/14 20:47:13 tom Exp $")
+
+NCURSES_EXPORT(WINDOW *)
+newpad(int l, int c)
+{
+    WINDOW *win;
+    NCURSES_CH_T *ptr;
+    int i;
+
+    T((T_CALLED("newpad(%d, %d)"), l, c));
+
+    if (l <= 0 || c <= 0)
+	returnWin(0);
+
+    if ((win = _nc_makenew(l, c, 0, 0, _ISPAD)) == NULL)
+	returnWin(0);
+
+    for (i = 0; i < l; i++) {
+	if_USE_SCROLL_HINTS(win->_line[i].oldindex = _NEWINDEX);
+	if ((win->_line[i].text = typeCalloc(NCURSES_CH_T, ((size_t) c))) == 0) {
+	    (void) _nc_freewin(win);
+	    returnWin(0);
+	}
+	for (ptr = win->_line[i].text; ptr < win->_line[i].text + c; ptr++)
+	    SetChar(*ptr, BLANK_TEXT, BLANK_ATTR);
+    }
+
+    returnWin(win);
+}
+
+NCURSES_EXPORT(WINDOW *)
+subpad(WINDOW *orig, int l, int c, int begy, int begx)
+{
+    WINDOW *win = (WINDOW *) 0;
+
+    T((T_CALLED("subpad(%d, %d)"), l, c));
+
+    if (orig) {
+	if (!(orig->_flags & _ISPAD)
+	    || ((win = derwin(orig, l, c, begy, begx)) == NULL))
+	    returnWin(0);
+    }
+    returnWin(win);
+}
+
+NCURSES_EXPORT(int)
+prefresh(WINDOW *win,
+	 int pminrow,
+	 int pmincol,
+	 int sminrow,
+	 int smincol,
+	 int smaxrow,
+	 int smaxcol)
+{
+    T((T_CALLED("prefresh()")));
+    if (pnoutrefresh(win, pminrow, pmincol, sminrow, smincol, smaxrow,
+		     smaxcol) != ERR
+	&& doupdate() != ERR) {
+	returnCode(OK);
+    }
+    returnCode(ERR);
+}
+
+NCURSES_EXPORT(int)
+pnoutrefresh(WINDOW *win,
+	     int pminrow,
+	     int pmincol,
+	     int sminrow,
+	     int smincol,
+	     int smaxrow,
+	     int smaxcol)
+{
+    NCURSES_SIZE_T i, j;
+    NCURSES_SIZE_T m, n;
+    NCURSES_SIZE_T pmaxrow;
+    NCURSES_SIZE_T pmaxcol;
+
+#if USE_SCROLL_HINTS
+    const int my_len = 2;	/* parameterize the threshold for hardscroll */
+    NCURSES_SIZE_T displaced;
+    bool wide;
+#endif
+
+    T((T_CALLED("pnoutrefresh(%p, %d, %d, %d, %d, %d, %d)"),
+       win, pminrow, pmincol, sminrow, smincol, smaxrow, smaxcol));
+
+    if (win == 0)
+	returnCode(ERR);
+
+    if (!(win->_flags & _ISPAD))
+	returnCode(ERR);
+
+    /* negative values are interpreted as zero */
+    if (pminrow < 0)
+	pminrow = 0;
+    if (pmincol < 0)
+	pmincol = 0;
+    if (sminrow < 0)
+	sminrow = 0;
+    if (smincol < 0)
+	smincol = 0;
+
+    pmaxrow = pminrow + smaxrow - sminrow;
+    pmaxcol = pmincol + smaxcol - smincol;
+
+    T((" pminrow + smaxrow - sminrow %ld, win->_maxy %ld",
+       (long) pmaxrow, (long) win->_maxy));
+    T((" pmincol + smaxcol - smincol %ld, win->_maxx %ld",
+       (long) pmaxcol, (long) win->_maxx));
+
+    /*
+     * Trim the caller's screen size back to the actual limits.
+     */
+    if (pmaxrow > win->_maxy) {
+	smaxrow -= (pmaxrow - win->_maxy);
+	pmaxrow = pminrow + smaxrow - sminrow;
+    }
+    if (pmaxcol > win->_maxx) {
+	smaxcol -= (pmaxcol - win->_maxx);
+	pmaxcol = pmincol + smaxcol - smincol;
+    }
+
+    if (smaxrow >= screen_lines
+	|| smaxcol >= screen_columns
+	|| sminrow > smaxrow
+	|| smincol > smaxcol)
+	returnCode(ERR);
+
+    T(("pad being refreshed"));
+
+#if USE_SCROLL_HINTS
+    if (win->_pad._pad_y >= 0) {
+	displaced = pminrow - win->_pad._pad_y
+	    - (sminrow - win->_pad._pad_top);
+	T(("pad being shifted by %d line(s)", displaced));
+    } else
+	displaced = 0;
+#endif
+
+    /*
+     * For pure efficiency, we'd want to transfer scrolling information
+     * from the pad to newscr whenever the window is wide enough that
+     * its update will dominate the cost of the update for the horizontal
+     * band of newscr that it occupies.  Unfortunately, this threshold
+     * tends to be complex to estimate, and in any case scrolling the
+     * whole band and rewriting the parts outside win's image would look
+     * really ugly.  So.  What we do is consider the pad "wide" if it
+     * either (a) occupies the whole width of newscr, or (b) occupies
+     * all but at most one column on either vertical edge of the screen
+     * (this caters to fussy people who put boxes around full-screen
+     * windows).  Note that changing this formula will not break any code,
+     * merely change the costs of various update cases.
+     */
+#if USE_SCROLL_HINTS
+    wide = (smincol < my_len && smaxcol > (newscr->_maxx - my_len));
+#endif
+
+    for (i = pminrow, m = sminrow + win->_yoffset;
+	 i <= pmaxrow && m <= newscr->_maxy;
+	 i++, m++) {
+	register struct ldat *nline = &newscr->_line[m];
+	register struct ldat *oline = &win->_line[i];
+	for (j = pmincol, n = smincol; j <= pmaxcol; j++, n++) {
+	    NCURSES_CH_T ch = oline->text[j];
+#if USE_WIDEC_SUPPORT
+	    /*
+	     * Special case for leftmost character of the displayed area.
+	     * Only half of a double-width character may be visible.
+	     */
+	    if (j == pmincol
+		&& j > 0
+		&& isWidecExt(ch)) {
+		SetChar(ch, L(' '), AttrOf(oline->text[j - 1]));
+	    }
+#endif
+	    if (!CharEq(ch, nline->text[n])) {
+		nline->text[n] = ch;
+		CHANGED_CELL(nline, n);
+	    }
+	}
+
+#if USE_SCROLL_HINTS
+	if (wide) {
+	    int nind = m + displaced;
+	    if (oline->oldindex < 0
+		|| nind < sminrow
+		|| nind > smaxrow) {
+		nind = _NEWINDEX;
+	    } else if (displaced) {
+		register struct ldat *pline = &curscr->_line[nind];
+		for (j = 0; j <= my_len; j++) {
+		    int k = newscr->_maxx - j;
+		    if (pline->text[j] != nline->text[j]
+			|| pline->text[k] != nline->text[k]) {
+			nind = _NEWINDEX;
+			break;
+		    }
+		}
+	    }
+
+	    nline->oldindex = nind;
+	}
+#endif /* USE_SCROLL_HINTS */
+	oline->firstchar = oline->lastchar = _NOCHANGE;
+	if_USE_SCROLL_HINTS(oline->oldindex = i);
+    }
+
+    /*
+     * Clean up debris from scrolling or resizing the pad, so we do not
+     * accidentally pick up the index value during the next call to this
+     * procedure.  The only rows that should have an index value are those
+     * that are displayed during this cycle.
+     */
+#if USE_SCROLL_HINTS
+    for (i = pminrow - 1; (i >= 0) && (win->_line[i].oldindex >= 0); i--)
+	win->_line[i].oldindex = _NEWINDEX;
+    for (i = pmaxrow + 1; (i <= win->_maxy)
+	 && (win->_line[i].oldindex >= 0); i++)
+	win->_line[i].oldindex = _NEWINDEX;
+#endif
+
+    win->_begx = smincol;
+    win->_begy = sminrow;
+
+    if (win->_clear) {
+	win->_clear = FALSE;
+	newscr->_clear = TRUE;
+    }
+
+    /*
+     * Use the pad's current position, if it will be visible.
+     * If not, don't do anything; it's not an error.
+     */
+    if (win->_leaveok == FALSE
+	&& win->_cury >= pminrow
+	&& win->_curx >= pmincol
+	&& win->_cury <= pmaxrow
+	&& win->_curx <= pmaxcol) {
+	newscr->_cury = win->_cury - pminrow + win->_begy + win->_yoffset;
+	newscr->_curx = win->_curx - pmincol + win->_begx;
+    }
+    newscr->_leaveok = win->_leaveok;
+    win->_flags &= ~_HASMOVED;
+
+    /*
+     * Update our cache of the line-numbers that we displayed from the pad.
+     * We will use this on subsequent calls to this function to derive
+     * values to stuff into 'oldindex[]' -- for scrolling optimization.
+     */
+    win->_pad._pad_y = pminrow;
+    win->_pad._pad_x = pmincol;
+    win->_pad._pad_top = sminrow;
+    win->_pad._pad_left = smincol;
+    win->_pad._pad_bottom = smaxrow;
+    win->_pad._pad_right = smaxcol;
+
+    returnCode(OK);
+}
+
+NCURSES_EXPORT(int)
+pechochar(WINDOW *pad, const chtype ch)
+{
+    T((T_CALLED("pechochar(%p, %s)"), pad, _tracechtype(ch)));
+
+    if (pad == 0)
+	returnCode(ERR);
+
+    if (!(pad->_flags & _ISPAD))
+	returnCode(wechochar(pad, ch));
+
+    waddch(pad, ch);
+    prefresh(pad, pad->_pad._pad_y,
+	     pad->_pad._pad_x,
+	     pad->_pad._pad_top,
+	     pad->_pad._pad_left,
+	     pad->_pad._pad_bottom,
+	     pad->_pad._pad_right);
+
+    returnCode(OK);
+}