michael@0: # Pretty-printers for JSID values.
michael@0: 
michael@0: import gdb
michael@0: import mozilla.prettyprinters
michael@0: import mozilla.Root
michael@0: 
michael@0: from mozilla.prettyprinters import pretty_printer
michael@0: 
michael@0: # Forget any printers from previous loads of this module.
michael@0: mozilla.prettyprinters.clear_module_printers(__name__)
michael@0: 
michael@0: @pretty_printer('jsid')
michael@0: class jsid(object):
michael@0:     # Since people don't always build with macro debugging info, I can't
michael@0:     # think of any way to avoid copying these values here, short of using
michael@0:     # inferior calls for every operation (which, I hear, is broken from
michael@0:     # pretty-printers in some recent GDBs).
michael@0:     TYPE_STRING                 = 0x0
michael@0:     TYPE_INT                    = 0x1
michael@0:     TYPE_VOID                   = 0x2
michael@0:     TYPE_OBJECT                 = 0x4
michael@0:     TYPE_MASK                   = 0x7
michael@0: 
michael@0:     def __init__(self, value, cache):
michael@0:         self.value = value
michael@0:         self.cache = cache
michael@0:         self.concrete_type = self.value.type.strip_typedefs()
michael@0: 
michael@0:     # SpiderMonkey has two alternative definitions of jsid: a typedef for
michael@0:     # ptrdiff_t, and a struct with == and != operators defined on it.
michael@0:     # Extract the bits from either one.
michael@0:     def as_bits(self):
michael@0:         if self.concrete_type.code == gdb.TYPE_CODE_STRUCT:
michael@0:             return self.value['asBits']
michael@0:         elif self.concrete_type.code == gdb.TYPE_CODE_INT:
michael@0:             return self.value
michael@0:         else:
michael@0:             raise RuntimeError, ("definition of SpiderMonkey 'jsid' type"
michael@0:                                  "neither struct nor integral type")
michael@0: 
michael@0:     def to_string(self):
michael@0:         bits = self.as_bits()
michael@0:         tag = bits & jsid.TYPE_MASK
michael@0:         if tag == jsid.TYPE_STRING:
michael@0:             body = bits.cast(self.cache.JSString_ptr_t)
michael@0:         elif tag & jsid.TYPE_INT:
michael@0:             body = bits >> 1
michael@0:         elif tag == jsid.TYPE_VOID:
michael@0:             return "JSID_VOID"
michael@0:         elif tag == jsid.TYPE_OBJECT:
michael@0:             body = ((bits & ~jsid.TYPE_MASK)
michael@0:                     .cast(self.cache.JSObject_ptr_t))
michael@0:         else:
michael@0:             body = "<unrecognized>"
michael@0:         return '$jsid(%s)' % (body,)
michael@0: 
michael@0: # Hard-code the referent type pretty-printer for jsid roots and handles.
michael@0: # See the comment for mozilla.Root.Common.__init__.
michael@0: @pretty_printer('JS::Rooted<long>')
michael@0: def RootedJSID(value, cache):
michael@0:     return mozilla.Root.Rooted(value, cache, jsid)
michael@0: @pretty_printer('JS::Handle<long>')
michael@0: def HandleJSID(value, cache):
michael@0:     return mozilla.Root.Handle(value, cache, jsid)
michael@0: @pretty_printer('JS::MutableHandle<long>')
michael@0: def MutableHandleJSID(value, cache):
michael@0:     return mozilla.Root.MutableHandle(value, cache, jsid)