From 61251bf0bf91165968d8d4577662ae60e4f9815a Mon Sep 17 00:00:00 2001
From: Keith Winstein <keithw@mit.edu>
Date: Thu, 10 Feb 2011 19:59:49 -0500
Subject: [PATCH] Implement wrapped flag on output (can turn on and off wrap in
 terminal)

---
 terminal.cpp        | 14 ++++++++++++++
 terminaldisplay.cpp | 31 +++++++++++++++++++++++++++++++
 2 files changed, 45 insertions(+)

diff --git a/terminal.cpp b/terminal.cpp
index 8e76f4d..6d21a1f 100644
--- a/terminal.cpp
+++ b/terminal.cpp
@@ -45,6 +45,20 @@ void Emulator::print( Parser::Print *act )
       fb.move_rows_autoscroll( 1 );
     }
 
+    /* wrap 2-cell chars if no room, even without will-wrap flag */
+    if ( fb.ds.auto_wrap_mode
+	 && (chwidth == 2)
+	 && (fb.ds.get_cursor_col() == fb.ds.get_width() - 1) ) {
+      this_cell->reset();
+      fb.get_row( -1 )->wrap = false;
+      /* There doesn't seem to be a consistent way to get the
+	 downstream terminal emulator to set the wrap-around
+	 copy-and-paste flag on a row that ends with an empty cell
+	 because a wide char was wrapped to the next line. */
+      fb.ds.move_col( 0 );
+      fb.move_rows_autoscroll( 1 );
+    }
+
     if ( fb.ds.insert_mode ) {
       for ( int i = 0; i < chwidth; i++ ) {
 	fb.insert_cell( fb.ds.get_cursor_row(), fb.ds.get_cursor_col() );
diff --git a/terminaldisplay.cpp b/terminaldisplay.cpp
index 3611169..71091ec 100644
--- a/terminaldisplay.cpp
+++ b/terminaldisplay.cpp
@@ -1,3 +1,5 @@
+#include <assert.h>
+
 #include "terminaldisplay.hpp"
 
 using namespace Terminal;
@@ -49,7 +51,36 @@ std::string Display::new_frame( Framebuffer &f )
 
   /* iterate for every cell */
   for ( y = 0; y < f.ds.get_height(); y++ ) {
+    int last_x = 0;
     for ( x = 0; x < f.ds.get_width(); /* let charwidth handle advance */ ) {
+      last_x = x;
+      put_cell( f );
+
+      /* To hint that a word-select should group the end of one line
+	 with the beginning of the next, we let the real cursor
+	 actually wrap around in cases where it wrapped around for us. */
+
+      if ( (cursor_x >= f.ds.get_width())
+	   && (y < f.ds.get_height() - 1)
+	   && f.get_row( y )->wrap
+	   && (!initialized || !last_frame.get_row( y )->wrap) ) {
+	/* next write will wrap */
+	cursor_x = 0;
+	cursor_y++;
+      }
+    }
+
+    /* Turn off wrap */
+    if ( (y < f.ds.get_height() - 1)
+	 && (!f.get_row( y )->wrap)
+	 && (!initialized || last_frame.get_row( y )->wrap) ) {
+      x = last_x;
+      last_frame.get_cell( y, x )->reset();
+
+      snprintf( tmp, 64, "\033[%d;%dH\033[K", y + 1, x + 1 );
+      str.append( tmp );
+      cursor_x = x;
+
       put_cell( f );
     }
   }