X-Git-Url: https://ncurses.scripts.mit.edu/?p=ncurses.git;a=blobdiff_plain;f=ncurses%2Fbase%2Flib_scroll.c;h=ecc0ba569fe2c947ab967d30e2d51b01d984088c;hp=f8e16bafa8743cec7264f92db7e9de66aa240743;hb=7f4b9f390624835ceb0849965a7f6ff2dcb39d00;hpb=a8987e73ec254703634802b4f7ee30d3a485524d

diff --git a/ncurses/base/lib_scroll.c b/ncurses/base/lib_scroll.c
index f8e16baf..ecc0ba56 100644
--- a/ncurses/base/lib_scroll.c
+++ b/ncurses/base/lib_scroll.c
@@ -1,5 +1,6 @@
 /****************************************************************************
- * Copyright (c) 1998,2001,2003 Free Software Foundation, Inc.              *
+ * Copyright 2019,2020 Thomas E. Dickey                                     *
+ * Copyright 1998-2010,2011 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            *
@@ -43,18 +44,22 @@
 
 #include <curses.priv.h>
 
-MODULE_ID("$Id: lib_scroll.c,v 1.24 2003/07/26 23:25:26 tom Exp $")
+MODULE_ID("$Id: lib_scroll.c,v 1.32 2020/02/02 23:34:34 tom Exp $")
 
 NCURSES_EXPORT(void)
-_nc_scroll_window(WINDOW *win, int const n, NCURSES_SIZE_T const top,
-		  NCURSES_SIZE_T const bottom, NCURSES_CH_T blank)
+_nc_scroll_window(WINDOW *win,
+		  int const n,
+		  int const top,
+		  int const bottom,
+		  NCURSES_CH_T blank)
 {
     int limit;
     int line;
     int j;
-    size_t to_copy = (size_t) (sizeof(NCURSES_CH_T) * (win->_maxx + 1));
+    size_t to_copy = (sizeof(NCURSES_CH_T) * (size_t) (win->_maxx + 1));
 
-    TR(TRACE_MOVE, ("_nc_scroll_window(%p, %d, %d, %d)", win, n, top, bottom));
+    TR(TRACE_MOVE, ("_nc_scroll_window(%p, %d, %ld, %ld)",
+		    (void *) win, n, (long) top, (long) bottom));
 
     if (top < 0
 	|| bottom < top
@@ -73,11 +78,13 @@ _nc_scroll_window(WINDOW *win, int const n, NCURSES_SIZE_T const top,
      * setup cost.  So there is no point in trying to be excessively
      * clever -- esr.
      */
+#define BottomLimit(n) ((n) >= 0 && (n) >= top)
+#define TopLimit(n)    ((n) <= win->_maxy && (n) <= bottom)
 
     /* shift n lines downwards */
     if (n < 0) {
 	limit = top - n;
-	for (line = bottom; line >= limit && line >= 0; line--) {
+	for (line = bottom; line >= limit && BottomLimit(line); line--) {
 	    TR(TRACE_MOVE, ("...copying %d to %d", line + n, line));
 	    memcpy(win->_line[line].text,
 		   win->_line[line + n].text,
@@ -85,7 +92,7 @@ _nc_scroll_window(WINDOW *win, int const n, NCURSES_SIZE_T const top,
 	    if_USE_SCROLL_HINTS(win->_line[line].oldindex =
 				win->_line[line + n].oldindex);
 	}
-	for (line = top; line < limit && line <= win->_maxy; line++) {
+	for (line = top; line < limit && TopLimit(line); line++) {
 	    TR(TRACE_MOVE, ("...filling %d", line));
 	    for (j = 0; j <= win->_maxx; j++)
 		win->_line[line].text[j] = blank;
@@ -96,26 +103,42 @@ _nc_scroll_window(WINDOW *win, int const n, NCURSES_SIZE_T const top,
     /* shift n lines upwards */
     if (n > 0) {
 	limit = bottom - n;
-	for (line = top; line <= limit && line <= win->_maxy; line++) {
+	for (line = top; line <= limit && TopLimit(line); line++) {
 	    memcpy(win->_line[line].text,
 		   win->_line[line + n].text,
 		   to_copy);
 	    if_USE_SCROLL_HINTS(win->_line[line].oldindex =
 				win->_line[line + n].oldindex);
 	}
-	for (line = bottom; line > limit && line >= 0; line--) {
+	for (line = bottom; line > limit && BottomLimit(line); line--) {
 	    for (j = 0; j <= win->_maxx; j++)
 		win->_line[line].text[j] = blank;
 	    if_USE_SCROLL_HINTS(win->_line[line].oldindex = _NEWINDEX);
 	}
     }
     touchline(win, top, bottom - top + 1);
+
+    if_WIDEC({
+	if (WINDOW_EXT(win, addch_used) != 0) {
+	    int next = WINDOW_EXT(win, addch_y) + n;
+	    if (next < 0 || next > win->_maxy) {
+		TR(TRACE_VIRTPUT,
+		   ("Alert discarded multibyte on scroll"));
+		WINDOW_EXT(win, addch_y) = 0;
+	    } else {
+		TR(TRACE_VIRTPUT, ("scrolled working position to %d,%d",
+				   WINDOW_EXT(win, addch_y),
+				   WINDOW_EXT(win, addch_x)));
+		WINDOW_EXT(win, addch_y) = next;
+	    }
+	}
+    })
 }
 
 NCURSES_EXPORT(int)
 wscrl(WINDOW *win, int n)
 {
-    T((T_CALLED("wscrl(%p,%d)"), win, n));
+    T((T_CALLED("wscrl(%p,%d)"), (void *) win, n));
 
     if (!win || !win->_scroll) {
 	TR(TRACE_MOVE, ("...scrollok is false"));