vte (gtk2): apply change-scroll-region.patch (close #9688)

More info (including upstream fix):
https://github.com/mobile-shell/moshweb/blob/cb07c674787c083d82f6a1c68a3edbd50332f2ba/index.html#L754-L773
Patch from: https://bug542087.bugzilla-attachments.gnome.org/attachment.cgi?id=176035

2 files changed, 68 insertions, 0 deletions

diff --git a/pkgs/desktops/gnome-2/desktop/vte/change-scroll-region.patch b/pkgs/desktops/gnome-2/desktop/vte/change-scroll-region.patch
new file mode 100644
index 000000000000..9e3e83b1262a
--- /dev/null
+++ b/pkgs/desktops/gnome-2/desktop/vte/change-scroll-region.patch
@@ -0,0 +1,67 @@
+Index: vte-0.26.0/src/vte.c
+===================================================================
+--- vte-0.26.0.orig/src/vte.c	2010-11-30 23:04:53.000000000 -0800
++++ vte-0.26.0/src/vte.c	2010-12-07 20:05:07.865548000 -0800
+@@ -3862,6 +3862,7 @@ vte_terminal_process_incoming(VteTermina
+ 	long wcount, start, delta;
+ 	gboolean leftovers, modified, bottom, again;
+ 	gboolean invalidated_text;
++	gboolean in_scroll_region;
+ 	GArray *unichars;
+ 	struct _vte_incoming_chunk *chunk, *next_chunk, *achunk = NULL;
+ 
+@@ -3881,6 +3882,10 @@ vte_terminal_process_incoming(VteTermina
+ 	cursor = screen->cursor_current;
+ 	cursor_visible = terminal->pvt->cursor_visible;
+ 
++	in_scroll_region = screen->scrolling_restricted
++	    && (screen->cursor_current.row >= (screen->insert_delta + screen->scrolling_region.start))
++	    && (screen->cursor_current.row <= (screen->insert_delta + screen->scrolling_region.end));
++
+ 	/* We should only be called when there's data to process. */
+ 	g_assert(terminal->pvt->incoming ||
+ 		 (terminal->pvt->pending->len > 0));
+@@ -3979,6 +3984,8 @@ skip_chunk:
+ 		 * points to the first character which isn't part of this
+ 		 * sequence. */
+ 		if ((match != NULL) && (match[0] != '\0')) {
++			gboolean new_in_scroll_region;
++
+ 			/* Call the right sequence handler for the requested
+ 			 * behavior. */
+ 			_vte_terminal_handle_sequence(terminal,
+@@ -3989,12 +3996,20 @@ skip_chunk:
+ 			start = (next - wbuf);
+ 			modified = TRUE;
+ 
+-			/* if we have moved during the sequence handler, restart the bbox */
++			new_in_scroll_region = screen->scrolling_restricted
++			    && (screen->cursor_current.row >= (screen->insert_delta + screen->scrolling_region.start))
++			    && (screen->cursor_current.row <= (screen->insert_delta + screen->scrolling_region.end));
++
++			delta = screen->scroll_delta;	/* delta may have changed from sequence. */
++
++			/* if we have moved greatly during the sequence handler, or moved into a scroll_region
++                         * from outside it, restart the bbox */
+ 			if (invalidated_text &&
+-					(screen->cursor_current.col > bbox_bottomright.x + VTE_CELL_BBOX_SLACK ||
+-					 screen->cursor_current.col < bbox_topleft.x - VTE_CELL_BBOX_SLACK     ||
+-					 screen->cursor_current.row > bbox_bottomright.y + VTE_CELL_BBOX_SLACK ||
+-					 screen->cursor_current.row < bbox_topleft.y - VTE_CELL_BBOX_SLACK)) {
++					((new_in_scroll_region && !in_scroll_region) ||
++					 (screen->cursor_current.col > bbox_bottomright.x + VTE_CELL_BBOX_SLACK ||
++					  screen->cursor_current.col < bbox_topleft.x - VTE_CELL_BBOX_SLACK     ||
++					  screen->cursor_current.row > bbox_bottomright.y + VTE_CELL_BBOX_SLACK ||
++					  screen->cursor_current.row < bbox_topleft.y - VTE_CELL_BBOX_SLACK))) {
+ 				/* Clip off any part of the box which isn't already on-screen. */
+ 				bbox_topleft.x = MAX(bbox_topleft.x, 0);
+ 				bbox_topleft.y = MAX(bbox_topleft.y, delta);
+@@ -4014,6 +4029,8 @@ skip_chunk:
+ 				bbox_bottomright.x = bbox_bottomright.y = -G_MAXINT;
+ 				bbox_topleft.x = bbox_topleft.y = G_MAXINT;
+ 			}
++
++			in_scroll_region = new_in_scroll_region;
+ 		} else
+ 		/* Second, we have a NULL match, and next points to the very
+ 		 * next character in the buffer.  Insert the character which
diff --git a/pkgs/desktops/gnome-2/desktop/vte/default.nix b/pkgs/desktops/gnome-2/desktop/vte/default.nix
index 5932caf9e97d..b086c64abff8 100644
--- a/pkgs/desktops/gnome-2/desktop/vte/default.nix
+++ b/pkgs/desktops/gnome-2/desktop/vte/default.nix
@@ -11,6 +11,7 @@ stdenv.mkDerivation rec {
 
   patches = [
     ./alt.patch
+    ./change-scroll-region.patch
     # CVE-2012-2738
     ./vte-0.28.2-limit-arguments.patch
   ];