1) Redo internal interface to be more latest ncurses-like

2) Fix winsdel called in last line of the window (nothing happens in
   old variant)
3) Add range checks to wscrl() and internal soft scroll function

3 files changed, 82 insertions, 73 deletions

diff --git a/lib/libncurses/curses.priv.h b/lib/libncurses/curses.priv.h
index 85f54b7..73e3d7d 100644
--- a/lib/libncurses/curses.priv.h
+++ b/lib/libncurses/curses.priv.h
@@ -64,6 +64,7 @@ extern WINDOW *makenew(int, int, int, int);
 extern int timed_wait(int fd, int wait, int *timeleft);
 extern chtype _nc_background(WINDOW *);
 extern chtype _nc_render(WINDOW *, chtype);
+extern void _nc_scroll_window(WINDOW *, int, short const, short const, chtype);
 
 struct try {
         struct try      *child;     /* ptr to child.  NULL if none          */
diff --git a/lib/libncurses/lib_insdel.c b/lib/libncurses/lib_insdel.c
index eb30f20..8729efe 100644
--- a/lib/libncurses/lib_insdel.c
+++ b/lib/libncurses/lib_insdel.c
@@ -12,40 +12,20 @@
 **
 */
 
-#include <stdlib.h>
 #include "curses.priv.h"
-#include "terminfo.h"
 
 int
 winsdelln(WINDOW *win, int n)
 {
-	int ret, sscroll, stop, sbot;
+int code = ERR;
 
 	T(("winsdel(%x,%d) called", win, n));
 
-	if (n == 0)
-		return OK;
-	if (win->_cury == win->_maxy && abs(n) == 1)
-		return wclrtoeol(win);
-	if (n < 0 && win->_cury - n > win->_maxy)
-		/* request to delete too many lines */
-		/* should we truncate to an appropriate number? */
-		return ERR;
-
-	sscroll = win->_scroll;
-	stop = win->_regtop;
-	sbot = win->_regbottom;
-
-	win->_scroll = TRUE;
-	win->_regtop = win->_cury;
-	if (win->_regtop > win->_regbottom)
-		win->_regbottom = win->_maxy;
-
-	ret = wscrl(win, -n);
-
-	win->_scroll = sscroll;
-	win->_regtop = stop;
-	win->_regbottom = sbot;
-
-	return ret;
+	if (win) {
+	  if (n != 0) {
+	    _nc_scroll_window(win, -n, win->_cury, win->_maxy, _nc_background(win));	  
+	  }
+	  code = OK;
+	}
+	return code;
 }
diff --git a/lib/libncurses/lib_scroll.c b/lib/libncurses/lib_scroll.c
index 03e7136..5dd55d6 100644
--- a/lib/libncurses/lib_scroll.c
+++ b/lib/libncurses/lib_scroll.c
@@ -16,30 +16,30 @@
 #include "curses.priv.h"
 #include "terminfo.h"
 
-void scroll_window(WINDOW *win, int n, int regtop, int regbottom)
+void _nc_soft_scroll_window(WINDOW *win, int const n, short const top, short const bottom, chtype blank)
 {
 int	line, i;
 chtype	*ptr, *temp;
 chtype  **saved;
-chtype	blank = _nc_background(win);
 
-    	saved = (chtype **)malloc(sizeof(chtype *) * abs(n));
+	saved = (chtype **)calloc(abs(n), sizeof(chtype *));
 
     	if (n < 0) {
 		/* save overwritten lines */
 
-		for (i = 0; i < -n; i++)
-			saved[i] = win->_line[regbottom-i];
+		for (i = 0; i < -n && bottom-i >= 0; i++)
+			saved[i] = win->_line[bottom-i];
 
 		/* shift n lines */
 
-		for (line = regbottom; line >= regtop-n; line--)
+		for (line = bottom; line >= top-n && line >= 0; line--)
 			win->_line[line] = win->_line[line+n];
 
 		/* restore saved lines and blank them */
 
-		for (i = 0, line = regtop; line < regtop-n; line++, i++) {
-			win->_line[line] = saved[i];
+		for (i = 0, line = top; line < top-n && line <= win->_maxy; line++, i++) {
+			if (saved[i])
+				win->_line[line] = saved[i];
 			temp = win->_line[line];
 		    	for (ptr = temp; ptr - temp <= win->_maxx; ptr++)
 				*ptr = blank;
@@ -47,47 +47,56 @@ chtype	blank = _nc_background(win);
 	} else {
 		/* save overwritten lines */
 
-		for (i = 0; i < n; i++)
-			saved[i] = win->_line[regtop+i];
+		for (i = 0; i < n && top+i <= win->_maxy; i++)
+			saved[i] = win->_line[top+i];
 
 		/* shift n lines */
 
-		for (line = regtop; line <= regbottom-n; line++)
+		for (line = top; line <= bottom-n && line+n <= win->_maxy; line++)
 			win->_line[line] = win->_line[line+n];
 
 		/* restore saved lines and blank them */
 
-		for (i = 0, line = regbottom; line > regbottom - n; line--, i++) {
-			win->_line[line] = saved[i];
+		for (i = 0, line = bottom; line > bottom - n && line >= 0; line--, i++) {
+			if (saved[i])
+				win->_line[line] = saved[i];
 			temp = win->_line[line];
 		    	for (ptr = temp; ptr - temp <= win->_maxx; ptr++)
 				*ptr = blank;
 		}
 	}
-
+	/* touchline(win, top, bottom-top+1); */        /* not yet */
 	free(saved);
 }
 
-int
-wscrl(WINDOW *win, int n)
+void _nc_scroll_window(WINDOW *win, int n, short const top, short const bottom, chtype blank)
 {
 int physical = FALSE;
 int i;
 
-	T(("wscrl(%x,%d) called", win, n));
+	if (top == bottom) {
+		int sy, sx;
 
-	if (! win->_scroll)
-		return ERR;
+		getyx(win, sy, sx);
+		win->_curx = 0;
+		win->_cury = top;
+		wclrtoeol(win);
+		win->_curx = sx;
+		win->_cury = sy;
+		return;
+	}
 
-	if (n == 0)
-		return OK;
+	if (n > lines)
+		n = lines;
+	else if (-n > lines)
+		n = -lines;
 
 	/* as an optimization, if the scrolling region is the entire screen
 	   scroll the physical screen */
 
 	if (   win->_begx == 0 && win->_maxx == columns - 1
 	    && !memory_above && !memory_below
-	    && ((((win->_begy+win->_regtop == 0 && win->_begy+win->_regbottom == lines - 1)
+	    && ((((win->_begy+top == 0 && win->_begy+bottom == lines - 1)
 		  || change_scroll_region)
 		 && (   (n < 0 && (parm_rindex || scroll_reverse))
 		     || (n > 0 && (parm_index || scroll_forward))
@@ -97,28 +106,28 @@ int i;
 		     )
 	       )
 	   )
-    		physical = TRUE;
+		physical = TRUE;
 
 	if (physical == TRUE) {
 		wrefresh(win);
-		scroll_window(curscr, n, win->_begy+win->_regtop, win->_begy+win->_regbottom);
-		scroll_window(newscr, n, win->_begy+win->_regtop, win->_begy+win->_regbottom);
+		_nc_soft_scroll_window(curscr, n, win->_begy+top, win->_begy+bottom, blank);
+		_nc_soft_scroll_window(newscr, n, win->_begy+top, win->_begy+bottom, blank);
 	}
-	scroll_window(win, n, win->_regtop, win->_regbottom);
+	_nc_soft_scroll_window(win, n, top, bottom, blank);
 
 	if (physical == TRUE) {
 		if (n < 0) {
-			if (   ((   win->_begy+win->_regtop == 0
-				 && win->_begy+win->_regbottom == lines - 1)
+			if (   ((   win->_begy+top == 0
+				 && win->_begy+bottom == lines - 1)
 				|| change_scroll_region)
 			    && (parm_rindex || scroll_reverse)
 			   ) {
 				if (change_scroll_region &&
-				    (win->_begy+win->_regtop != 0 || win->_begy+win->_regbottom != lines - 1)
+				    (win->_begy+top != 0 || win->_begy+bottom != lines - 1)
 				   )
-					putp(tparm(change_scroll_region, win->_begy+win->_regtop, win->_begy+win->_regbottom));
+					putp(tparm(change_scroll_region, win->_begy+top, win->_begy+bottom));
 				i = abs(n);
-				mvcur(-1, -1, win->_begy+win->_regtop, 0);
+				mvcur(-1, -1, win->_begy+top, 0);
 				if (parm_rindex) {
 					putp(tparm(parm_rindex, i));
 				} else if (scroll_reverse) {
@@ -126,13 +135,13 @@ int i;
 						putp(scroll_reverse);
 				}
 				if (change_scroll_region &&
-				    (win->_begy+win->_regtop != 0 || win->_begy+win->_regbottom != lines - 1)
+				    (win->_begy+top != 0 || win->_begy+bottom != lines - 1)
 				   )
 					putp(tparm(change_scroll_region, 0, lines-1));
 			} else {
 				i = abs(n);
-				if (win->_begy+win->_regbottom < lines - 1) {
-					mvcur(-1, -1, win->_begy+win->_regbottom, 0);
+				if (win->_begy+bottom < lines - 1) {
+					mvcur(-1, -1, win->_begy+bottom, 0);
 					if (parm_delete_line) {
 						putp(tparm(parm_delete_line, i));
 					} else if (delete_line) {
@@ -141,7 +150,7 @@ int i;
 						i = abs(n);
 					}
 				}
-				mvcur(-1, -1, win->_begy+win->_regtop, 0);
+				mvcur(-1, -1, win->_begy+top, 0);
 				if (parm_insert_line) {
 					putp(tparm(parm_insert_line, i));
 				} else if (insert_line) {
@@ -150,16 +159,16 @@ int i;
 				}
 			}
 		} else {
-			if (   ((   win->_begy+win->_regtop == 0
-				 && win->_begy+win->_regbottom == lines - 1)
+			if (   ((   win->_begy+top == 0
+				 && win->_begy+bottom == lines - 1)
 				|| change_scroll_region)
 			    && (parm_index || scroll_forward)
 			   ) {
 				if (change_scroll_region &&
-				    (win->_begy+win->_regtop != 0 || win->_begy+win->_regbottom != lines - 1)
+				    (win->_begy+top != 0 || win->_begy+bottom != lines - 1)
 				   )
-					putp(tparm(change_scroll_region, win->_begy+win->_regtop, win->_begy+win->_regbottom));
-				mvcur(-1, -1, win->_begy+win->_regbottom, 0);
+					putp(tparm(change_scroll_region, win->_begy+top, win->_begy+bottom));
+				mvcur(-1, -1, win->_begy+bottom, 0);
 				if (parm_index) {
 					putp(tparm(parm_index, n));
 				} else if (scroll_forward) {
@@ -168,11 +177,11 @@ int i;
 						putp(scroll_forward);
 				}
 				if (change_scroll_region &&
-				    (win->_begy+win->_regtop != 0 || win->_begy+win->_regbottom != lines - 1)
+				    (win->_begy+top != 0 || win->_begy+bottom != lines - 1)
 				   )
 					putp(tparm(change_scroll_region, 0, lines-1));
 			} else {
-				mvcur(-1, -1, win->_begy+win->_regtop, 0);
+				mvcur(-1, -1, win->_begy+top, 0);
 				if (parm_delete_line) {
 					putp(tparm(parm_delete_line, n));
 				} else if (delete_line) {
@@ -180,8 +189,8 @@ int i;
 					while (i--)
 						putp(delete_line);
 				}
-				if (win->_begy+win->_regbottom < lines - 1) {
-					mvcur(win->_begy+win->_regtop, 0, win->_begy+win->_regbottom, 0);
+				if (win->_begy+bottom < lines - 1) {
+					mvcur(win->_begy+top, 0, win->_begy+bottom, 0);
 					if (parm_insert_line) {
 						putp(tparm(parm_insert_line, n));
 					} else if (insert_line) {
@@ -195,7 +204,26 @@ int i;
 
 		mvcur(-1, -1, win->_begy+win->_cury, win->_begx+win->_curx);
 	} else
-	    	touchline(win, win->_regtop, win->_regbottom - win->_regtop + 1);
+		touchline(win, top, bottom - top + 1);
+}
+
+
+int
+wscrl(WINDOW *win, int n)
+{
+	T(("wscrl(%x,%d) called", win, n));
+
+	if (!win || !win->_scroll)
+		return ERR;
+
+	if (n == 0)
+		return OK;
+
+	if ((n > (win->_regbottom - win->_regtop)) || 
+	    (-n > (win->_regbottom - win->_regtop)))
+	    return ERR;
+
+	_nc_scroll_window(win, n, win->_regtop, win->_regbottom, _nc_background(win));
 
     	return OK;
 }