lldb/examples/summaries/cocoa/CFDictionary.py

# summary provider for NSDictionary
import lldb
import ctypes
import objc_runtime
import metrics

statistics = metrics.Metrics()
statistics.add_metric('invalid_isa')
statistics.add_metric('invalid_pointer')
statistics.add_metric('unknown_class')
statistics.add_metric('code_notrun')

# despite the similary to synthetic children providers, these classes are not
# trying to provide anything but the count for an NSDictionary, so they need not
# obey the interface specification for synthetic children providers
class NSCFDictionary_SummaryProvider:
	def adjust_for_architecture(self):
		pass

	def __init__(self, valobj, params):
		self.valobj = valobj;
		self.sys_params = params
		if not(self.sys_params.types_cache.NSUInteger):
			if self.sys_params.is_64_bit:
				self.sys_params.types_cache.NSUInteger = self.valobj.GetType().GetBasicType(lldb.eBasicTypeUnsignedLong)
			else:
				self.sys_params.types_cache.NSUInteger = self.valobj.GetType().GetBasicType(lldb.eBasicTypeUnsignedInt)
		self.update();

	def update(self):
		self.adjust_for_architecture();

	# empirically determined on both 32 and 64bit desktop Mac OS X
	# probably boils down to 2 pointers and 4 bytes of data, but
	# the description of __CFDictionary is not readily available so most
	# of this is guesswork, plain and simple
	def offset(self):
		if self.sys_params.is_64_bit:
			return 20
		else:
			return 12

	def num_children(self):
		num_children_vo = self.valobj.CreateChildAtOffset("count",
							self.offset(),
							self.sys_params.types_cache.NSUInteger)
		return num_children_vo.GetValueAsUnsigned(0)


class NSDictionaryI_SummaryProvider:
	def adjust_for_architecture(self):
		pass

	def __init__(self, valobj, params):
		self.valobj = valobj;
		self.sys_params = params
		if not(self.sys_params.types_cache.NSUInteger):
			if self.sys_params.is_64_bit:
				self.sys_params.types_cache.NSUInteger = self.valobj.GetType().GetBasicType(lldb.eBasicTypeUnsignedLong)
			else:
				self.sys_params.types_cache.NSUInteger = self.valobj.GetType().GetBasicType(lldb.eBasicTypeUnsignedInt)
		self.update();

	def update(self):
		self.adjust_for_architecture();

	# we just need to skip the ISA and the count immediately follows
	def offset(self):
		return self.sys_params.pointer_size

	def num_children(self):
		num_children_vo = self.valobj.CreateChildAtOffset("count",
							self.offset(),
							self.sys_params.types_cache.NSUInteger)
		value = num_children_vo.GetValueAsUnsigned(0)
		if value != None:
			# the MS6bits on immutable dictionaries seem to be taken by the LSB of capacity
			# not sure if it is a bug or some weird sort of feature, but masking that out
			# gets the count right
			if self.sys_params.is_64_bit:
				value = value & ~0xFC00000000000000
			else:
				value = value & ~0xFC000000
		return value

class NSDictionaryM_SummaryProvider:
	def adjust_for_architecture(self):
		pass

	def __init__(self, valobj, params):
		self.valobj = valobj;
		self.sys_params = params
		if not(self.sys_params.types_cache.NSUInteger):
			if self.sys_params.is_64_bit:
				self.sys_params.types_cache.NSUInteger = self.valobj.GetType().GetBasicType(lldb.eBasicTypeUnsignedLong)
			else:
				self.sys_params.types_cache.NSUInteger = self.valobj.GetType().GetBasicType(lldb.eBasicTypeUnsignedInt)
		self.update();

	def update(self):
		self.adjust_for_architecture();

	# we just need to skip the ISA and the count immediately follows
	def offset(self):
		return self.sys_params.pointer_size

	def num_children(self):
		num_children_vo = self.valobj.CreateChildAtOffset("count",
							self.offset(),
							self.sys_params.types_cache.NSUInteger)
		value = num_children_vo.GetValueAsUnsigned(0)
		if value != None:
			# the MS6bits on immutable dictionaries seem to be taken by the LSB of capacity
			# not sure if it is a bug or some weird sort of feature, but masking that out
			# gets the count right
			if self.sys_params.is_64_bit:
				value = value & ~0xFC00000000000000
			else:
				value = value & ~0xFC000000
		return value

class NSDictionaryUnknown_SummaryProvider:
	def adjust_for_architecture(self):
		pass

	def __init__(self, valobj, params):
		self.valobj = valobj;
		self.sys_params = params
		self.update();

	def update(self):
		self.adjust_for_architecture();

	def num_children(self):
		stream = lldb.SBStream()
		self.valobj.GetExpressionPath(stream)
		num_children_vo = self.valobj.CreateValueFromExpression("count","(int)[" + stream.GetData() + " count]");
		return num_children_vo.GetValueAsUnsigned(0)


def GetSummary_Impl(valobj):
	global statistics
	class_data = objc_runtime.ObjCRuntime(valobj)
	if class_data.is_valid() == False:
		statistics.metric_hit('invalid_pointer',valobj)
		wrapper = None
		return
	class_data = class_data.read_class_data()
	if class_data.is_valid() == False:
		statistics.metric_hit('invalid_isa',valobj)
		wrapper = None
		return
	if class_data.is_kvo():
		class_data = class_data.get_superclass()
	if class_data.is_valid() == False:
		statistics.metric_hit('invalid_isa',valobj)
		wrapper = None
		return
	
	name_string = class_data.class_name()
	if name_string == '__NSCFDictionary':
		wrapper = NSCFDictionary_SummaryProvider(valobj, class_data.sys_params)
		statistics.metric_hit('code_notrun',valobj)
	elif name_string == '__NSDictionaryI':
		wrapper = NSDictionaryI_SummaryProvider(valobj, class_data.sys_params)
		statistics.metric_hit('code_notrun',valobj)
	elif name_string == '__NSDictionaryM':
		wrapper = NSDictionaryM_SummaryProvider(valobj, class_data.sys_params)
		statistics.metric_hit('code_notrun',valobj)
	else:
		wrapper = NSDictionaryUnknown_SummaryProvider(valobj, class_data.sys_params)
		statistics.metric_hit('unknown_class',str(valobj) + " seen as " + name_string)
	return wrapper;

def CFDictionary_SummaryProvider (valobj,dict):
	provider = GetSummary_Impl(valobj);
	if provider != None:
	    try:
	        summary = provider.num_children();
	    except:
	        summary = None
	    if summary == None:
	        summary = 'no valid dictionary here'
	    return str(summary) + (" key/value pairs" if summary > 1 else " key/value pair")
	return ''

def CFDictionary_SummaryProvider2 (valobj,dict):
	provider = GetSummary_Impl(valobj);
	if provider != None:
		try:
			summary = provider.num_children();
		except:
			summary = None
		if summary == None:
			summary = 'no valid dictionary here'
		else:
		# needed on OSX Mountain Lion
			if provider.sys_params.is_64_bit:
				summary = summary & ~0x0f1f000000000000
			summary = '@"' + str(summary) + (' entries"' if summary > 1 else ' entry"')
		return summary
	return ''

def __lldb_init_module(debugger,dict):
	debugger.HandleCommand("type summary add -F CFDictionary.CFDictionary_SummaryProvider NSDictionary")
	debugger.HandleCommand("type summary add -F CFDictionary.CFDictionary_SummaryProvider2 CFDictionaryRef CFMutableDictionaryRef")