From cfd279fa2583f33a3e575cda226727b5c9bc8b06 Mon Sep 17 00:00:00 2001
From: Keith Winstein <keithw@mit.edu>
Date: Sat, 22 Jan 2011 04:58:01 -0500
Subject: [PATCH] Support wide characters and combining characters

---
 termemu.cpp     |  5 -----
 terminal.cpp    | 39 ++++++++++++++++++++++++++++++++++-----
 terminal.hpp    |  2 ++
 terminalcsi.cpp |  2 +-
 4 files changed, 37 insertions(+), 11 deletions(-)

diff --git a/termemu.cpp b/termemu.cpp
index a5af174..5f65d0b 100644
--- a/termemu.cpp
+++ b/termemu.cpp
@@ -64,11 +64,6 @@ int main( int argc __attribute__((unused)),
 
   if ( child == 0 ) {
     /* child */
-    if ( chdir( "/" ) < 0 ) {
-      perror( "chdir" );
-      exit( 1 );
-    }
-
     char *my_argv[ 2 ];
     my_argv[ 0 ] = strdup( "/bin/bash" );
     assert( my_argv[ 0 ] );
diff --git a/terminal.cpp b/terminal.cpp
index eabbd4c..5b7c942 100644
--- a/terminal.cpp
+++ b/terminal.cpp
@@ -38,7 +38,7 @@ Emulator::Emulator( size_t s_width, size_t s_height )
     cursor_col( 0 ), cursor_row( 0 ),
     combining_char_col( 0 ), combining_char_row( 0 ),
     rows( height, Row( width ) ),
-    params(), dispatch_chars(), parsed_params()
+    params(), dispatch_chars(), errors(), parsed_params()
 {
 
 }
@@ -126,6 +126,8 @@ void Emulator::print( Parser::Print *act )
 
   int chwidth = act->ch == L'\0' ? -1 : wcwidth( act->ch );
 
+  Cell *this_cell;
+
   switch ( chwidth ) {
   case 1: /* normal character */
   case 2: /* wide character */
@@ -136,13 +138,39 @@ void Emulator::print( Parser::Print *act )
 
     autoscroll();
 
-    rows[ cursor_row ].cells[ cursor_col ].contents.clear();
-    rows[ cursor_row ].cells[ cursor_col ].contents.push_back( act->ch );
+    this_cell =  &rows[ cursor_row ].cells[ cursor_col ];
+    this_cell->contents.clear();
+    this_cell->contents.push_back( act->ch );
+    for ( std::vector<Cell *>::iterator i
+	    = this_cell->overlapped_cells.begin();
+	  i != this_cell->overlapped_cells.end();
+	  i++ ) {
+      **i = Cell();
+    }
+    this_cell->overlapped_cells.clear();
+
     newgrapheme();
-    cursor_col++;
+
+    if ( cursor_col < width - 1 ) {
+      Cell *next_cell = &rows[ cursor_row ].cells[ cursor_col + 1 ];
+      if ( chwidth == 2 ) {
+	this_cell->overlapped_cells.push_back( next_cell );
+	next_cell->overlapping_cell = this_cell;
+      } else {
+	next_cell->overlapping_cell = NULL;
+      }
+    }
+
+    cursor_col += chwidth;
+    break;
+  case 0: /* combining character */
+    if ( rows[ combining_char_row ].cells[ combining_char_col ].contents.size() < 16 ) { /* seems like a reasonable limit on combining character */
+      rows[ combining_char_row ].cells[ combining_char_col ].contents.push_back( act->ch );
+    }
+  case -1: /* unprintable character */
     break;
   default:
-    break;
+    assert( false );
   }
 }
 
@@ -154,6 +182,7 @@ void Emulator::debug_printout( FILE *f )
     for ( int x = 0; x < width; x++ ) {
       fprintf( f, "\033[%d;%dH", y + 1, x + 1 );
       Cell *cell = &rows[ y ].cells[ x ];
+      if ( cell->overlapping_cell ) continue;
       for ( std::vector<wchar_t>::iterator i = cell->contents.begin();
 	    i != cell->contents.end();
 	    i++ ) {
diff --git a/terminal.hpp b/terminal.hpp
index 7ef0e52..de37ce1 100644
--- a/terminal.hpp
+++ b/terminal.hpp
@@ -46,6 +46,8 @@ namespace Terminal {
     std::string params;
     std::string dispatch_chars;
 
+    std::string errors;
+
     /* action methods */
     void print( Parser::Print *act );
     void execute( Parser::Execute *act );
diff --git a/terminalcsi.cpp b/terminalcsi.cpp
index 1fa06cb..5215e22 100644
--- a/terminalcsi.cpp
+++ b/terminalcsi.cpp
@@ -45,7 +45,7 @@ void Emulator::CSI_cursormove( void )
   if ( cursor_row < 0 ) cursor_row = 0;
   if ( cursor_row >= height ) cursor_row = height - 1;
   if ( cursor_col < 0 ) cursor_col = 0;
-  if ( cursor_col >= width ) cursor_col = width;
+  if ( cursor_col >= width ) cursor_col = width - 1;
 
   newgrapheme();
 }