--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/.hgignore	Sun Sep 08 23:18:16 2013 +0100
@@ -0,0 +1,4 @@
+syntax: glob
+*.pyc
+hacking.sublime-workspace
+

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hacking.sublime-project	Sun Sep 08 23:18:16 2013 +0100
@@ -0,0 +1,15 @@
+{
+	
+	"folders":
+	[
+	    {
+	    	"path" : "stx"
+	    },
+	],
+
+	"settings":
+	{
+	  "tab_size": 4,
+	  "translate_tabs_to_spaces": true
+	}
+}
\ No newline at end of file

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/stx/gdb/__init__.py	Sun Sep 08 23:18:16 2013 +0100
@@ -0,0 +1,1 @@
+import stx.gdb.commands
\ No newline at end of file

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/stx/gdb/commands.py	Sun Sep 08 23:18:16 2013 +0100
@@ -0,0 +1,95 @@
+import gdb
+import stx.support
+
+class CFrameDecorator ( stx.support.Decorator ):
+    """An abstract gdb.Frame decorator"""
+
+    @staticmethod
+    def decorate(frame):
+        if frame.function().name == '__jInterpret':
+            return CFrameDecorator_jInterpret(frame)
+        else:
+            return CFrameDecorator(frame)
+    
+    def __str__(self):
+        kind = self.kind()
+        if kind != None:
+            kind = "%2s" % kind
+        else:
+            kind = '  '
+        return "%3s 0x%8x %s ( %s)" % ( 
+            kind , 
+            self.pc(), 
+            self.name() , 
+            self.args_string() )
+
+    def older(self):
+        older = self._obj.older()
+        # special case, because of longjmp(), parent frame-point might point
+        # to clean area, filled by 0xa5a5a5a5 (malloc() does this)
+        if older.pc() != 0xa5a5a5a5:
+            return CFrameDecorator.decorate(older)
+        else:
+            return None
+
+    def newer(self):
+        return CFrameDecorator.decorate(self._obj.newer())
+
+    def kind(self):
+        """Returns 3 char identification of frame kind or None"""
+        return None # generic frame
+
+    def function_block(self):
+        """Returns a top-level block (i.e., block for the function)"""
+        b = self._obj.block()
+        while b.function == None:
+            b = b.superblock            
+        return b
+    
+    def args_string(self):
+        """Returns a string representation of arguments"""    
+        s = ''
+        for sym in self.function_block():
+            if sym.is_argument:
+                s = s + self.arg_string(sym) + ' '
+        return s
+    
+    def arg_string(self, sym):
+        """Given an argument symbol, returns its string representation"""
+        val = self._obj.read_var(sym, self._obj.block())
+        return "%s=%s" % ( sym.print_name , val )
+
+class CFrameDecorator_jInterpret ( CFrameDecorator ):
+
+    def kind(self):
+        return "J-I"
+        
+class Backtrace ( gdb.Command ):
+    '''
+    Prints a VM backtrace. 
+
+    Print additional information for well-known VM functions such
+    as __interpret, __jinterpret, etc.
+    '''
+    
+    def __init__ ( self ):
+        super (Backtrace, self).__init__("bt", gdb.COMMAND_STACK)
+    
+    def invoke ( self , args , from_tty ):
+        argv = gdb.string_to_argv(args)
+        limit = None
+        if len(argv) == 1:
+            limit = int(argv[0])
+        fno = 0        
+        frame = CFrameDecorator.decorate(gdb.newest_frame())
+        framesel = gdb.selected_frame()
+        while ( frame != None ) and ( limit == None or fno < limit ):            
+            if frame.target() == framesel:
+                star = '*'
+            else:
+                star = ' '
+            print "%s%3d %s" % (star, fno , frame )
+            frame = frame.older()
+            fno = fno +1
+
+Backtrace()
\ No newline at end of file

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/stx/gdb/load.py	Sun Sep 08 23:18:16 2013 +0100
@@ -0,0 +1,9 @@
+if __name__ == '__main__':
+    import os
+    import sys
+    my_dir = os.path.dirname(__file__)
+    inc_dir = os.path.join(my_dir, '../..')
+
+    sys.path.append(inc_dir)
+
+    import stx.gdb
\ No newline at end of file

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/stx/support.py	Sun Sep 08 23:18:16 2013 +0100
@@ -0,0 +1,24 @@
+class Decorator ( object ):
+    '''
+    Generic decorator class
+    '''
+
+    _obj = None
+
+    def __init__ ( self , obj ):
+        object.__setattr__(self, "_obj", obj)
+
+    def target(self):
+        return self._obj
+    
+    def __getattr__(self, aname):
+        target = self._obj
+        f = getattr(target, aname)
+        if isinstance(f, types.MethodType):
+            # Rebind the method to the target.
+            return new.instancemethod(f.im_func, self, target.__class__)
+        else:
+            return f
+
+    def __repr__( self ):
+        return "[" +str(self.__class__) + ' : ' + self._obj.__repr__() + "]"
\ No newline at end of file