GNU Screen: Support OSC 11 sequence (set background color)

screen-osc11.patch

diff -ur ansi.c ansi.c
--- ansi.c	2015-04-08 14:34:29.000000000 +0900
+++ ansi.c	2016-01-19 23:23:20.000000000 +0900
@@ -1554,12 +1554,10 @@
 	}
 #endif
 #ifdef RXVT_OSC
-      if (typ == 0 || typ == 1 || typ == 2 || typ == 20 || typ == 39 || typ == 49)
+      if (typ == 0 || typ == 1 || typ == 2 || typ == 11 || typ == 20 || typ == 39 || typ == 49)
 	{
 	  int typ2;
 	  typ2 = typ / 10;
-	  if (--typ2 < 0)
-	    typ2 = 0;
 	  if (strcmp(curr->w_xtermosc[typ2], p))
 	    {
 	      strncpy(curr->w_xtermosc[typ2], p, sizeof(curr->w_xtermosc[typ2]) - 1);
@@ -1571,7 +1569,7 @@
 		    continue;
 		  if (D_forecv->c_layer->l_bottom == &curr->w_layer)
 		    SetXtermOSC(typ2, curr->w_xtermosc[typ2]);
-		  if ((typ2 == 2 || typ2 == 3) && D_xtermosc[typ2])
+		  if ((typ2 == 3 || typ2 == 4) && D_xtermosc[typ2])
 		    Redisplay(0);
 		}
 	    }
diff -ur display.c display.c
--- display.c	2015-04-08 14:34:29.000000000 +0900
+++ display.c	2016-01-19 23:34:03.000000000 +0900
@@ -2883,6 +2883,7 @@
 {
   static char *oscs[][2] = {
     { WT_FLAG ";", "screen" }, /* set window title */
+    { "11;", "" },      /* background */
     { "20;", "" },      /* background */
     { "39;", "black" }, /* default foreground (black?) */
     { "49;", "white" }  /* default background (white?) */
@@ -2910,7 +2911,7 @@
 ClearAllXtermOSC()
 {
   int i;
-  for (i = 3; i >= 0; i--)
+  for (i = 4; i >= 0; i--)
     SetXtermOSC(i, 0);
   if (D_xtermosc[0])
     AddStr("\033[23;" WT_FLAG "t");	/* unstack titles (xterm patch #251) */
diff -ur process.c process.c
--- process.c	2015-04-08 14:34:29.000000000 +0900
+++ process.c	2016-01-19 23:25:21.000000000 +0900
@@ -7036,7 +7036,7 @@
     D_other = 0;
   flayer = D_forecv->c_layer;
 #ifdef RXVT_OSC
-  if (D_xtermosc[2] || D_xtermosc[3])
+  if (D_xtermosc[3] || D_xtermosc[4])
     {
       Activate(-1);
     }
@@ -7063,7 +7063,7 @@
   struct win *p;
 
   p = Layer2Window(D_forecv->c_layer);
-  for (i = 3; i >=0; i--)
+  for (i = 4; i >=0; i--)
     SetXtermOSC(i, p ? p->w_xtermosc[i] : 0);
 }
 #endif
diff -ur window.h window.h
--- window.h	2015-04-08 14:34:29.000000000 +0900
+++ window.h	2016-01-19 23:29:35.000000000 +0900
@@ -232,7 +232,7 @@
   char	 w_vbwait;
   char	 w_norefresh;		/* dont redisplay when switching to that win */
 #ifdef RXVT_OSC
-  char	 w_xtermosc[4][MAXSTR];	/* special xterm/rxvt escapes */
+  char	 w_xtermosc[5][MAXSTR];	/* special xterm/rxvt escapes */
 #endif
   int    w_mouse;		/* mouse mode 0,9,1000 */
 #ifdef HAVE_BRAILLE