| # Pretty-printers for SpiderMonkey JSObjects. |
| |
| import gdb |
| import mozilla.JSString |
| import mozilla.prettyprinters as prettyprinters |
| from mozilla.prettyprinters import ptr_pretty_printer, ref_pretty_printer |
| from mozilla.Root import deref |
| |
| prettyprinters.clear_module_printers(__name__) |
| |
| class JSObjectTypeCache(object): |
| def __init__(self, value, cache): |
| # In GDB 7.4.50, with some programs, this first dummy gdb.lookup_type |
| # call is required to make the second lookup_type call succeed. A GDB |
| # built from the public sources as of 2012-12-12 did not require the |
| # dummy lookup. |
| gdb.lookup_type('js::BaseShape') |
| baseshape_flags = gdb.lookup_type('js::BaseShape::Flag') |
| self.flag_DELEGATE = prettyprinters.enum_value(baseshape_flags, 'js::BaseShape::DELEGATE') |
| self.func_ptr_type = gdb.lookup_type('JSFunction').pointer() |
| |
| # There should be no need to register this for JSFunction as well, since we |
| # search for pretty-printers under the names of base classes, and |
| # JSFunction has JSObject as a base class. |
| |
| @ptr_pretty_printer('JSObject') |
| class JSObjectPtrOrRef(prettyprinters.Pointer): |
| def __init__(self, value, cache): |
| super(JSObjectPtrOrRef, self).__init__(value, cache) |
| if not cache.mod_JSObject: |
| cache.mod_JSObject = JSObjectTypeCache(value, cache) |
| self.otc = cache.mod_JSObject |
| |
| def summary(self): |
| shape = deref(self.value['shape_']) |
| baseshape = deref(shape['base_']) |
| class_name = baseshape['clasp']['name'].string() |
| flags = baseshape['flags'] |
| is_delegate = bool(flags & self.otc.flag_DELEGATE) |
| name = None |
| if class_name == 'Function': |
| function = self.value |
| concrete_type = function.type.strip_typedefs() |
| if concrete_type.code == gdb.TYPE_CODE_REF: |
| function = function.address |
| function = function.cast(self.otc.func_ptr_type) |
| atom = deref(function['atom_']) |
| name = str(atom) if atom else '<unnamed>' |
| return '[object %s%s]%s' % (class_name, |
| ' ' + name if name else '', |
| ' delegate' if is_delegate else '') |
| |
| @ref_pretty_printer('JSObject') |
| def JSObjectRef(value, cache): return JSObjectPtrOrRef(value, cache) |
