michael@0: # Pretty-printers for SpiderMonkey strings.
michael@0: 
michael@0: import gdb
michael@0: import mozilla.prettyprinters
michael@0: from mozilla.prettyprinters import pretty_printer, ptr_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: # Cache information about the JSString type for this objfile.
michael@0: class JSStringTypeCache(object):
michael@0:     def __init__(self, cache):
michael@0:         dummy = gdb.Value(0).cast(cache.JSString_ptr_t)
michael@0:         self.LENGTH_SHIFT = dummy['LENGTH_SHIFT']
michael@0:         self.FLAGS_MASK   = dummy['FLAGS_MASK']
michael@0:         self.ROPE_FLAGS   = dummy['ROPE_FLAGS']
michael@0:         self.ATOM_BIT     = dummy['ATOM_BIT']
michael@0: 
michael@0: class Common(mozilla.prettyprinters.Pointer):
michael@0:     def __init__(self, value, cache):
michael@0:         super(Common, self).__init__(value, cache)
michael@0:         if not cache.mod_JSString:
michael@0:             cache.mod_JSString = JSStringTypeCache(cache)
michael@0:         self.stc = cache.mod_JSString
michael@0: 
michael@0: @ptr_pretty_printer("JSString")
michael@0: class JSStringPtr(Common):
michael@0:     def display_hint(self):
michael@0:         return "string"
michael@0: 
michael@0:     def jschars(self):
michael@0:         d = self.value['d']
michael@0:         lengthAndFlags = d['lengthAndFlags']
michael@0:         length = lengthAndFlags >> self.stc.LENGTH_SHIFT
michael@0:         is_rope = (lengthAndFlags & self.stc.FLAGS_MASK) == self.stc.ROPE_FLAGS
michael@0:         if is_rope:
michael@0:             for c in JSStringPtr(d['u1']['left'], self.cache).jschars():
michael@0:                 yield c
michael@0:             for c in JSStringPtr(d['s']['u2']['right'], self.cache).jschars():
michael@0:                 yield c
michael@0:         else:
michael@0:             chars = d['u1']['chars']
michael@0:             for i in xrange(length):
michael@0:                 yield chars[i]
michael@0: 
michael@0:     def to_string(self):
michael@0:         s = u''
michael@0:         for c in self.jschars():
michael@0:             s += unichr(c)
michael@0:         return s
michael@0: 
michael@0: @ptr_pretty_printer("JSAtom")
michael@0: class JSAtomPtr(Common):
michael@0:     def to_string(self):
michael@0:         return self.value.cast(self.cache.JSString_ptr_t)