examples/summaries/cocoa/NSBundle.py

"""
LLDB AppKit formatters

part of The LLVM Compiler Infrastructure
This file is distributed under the University of Illinois Open Source
License. See LICENSE.TXT for details.
"""
# example summary provider for NSBundle
# the real summary is now C++ code built into LLDB
import lldb
import ctypes
import lldb.runtime.objc.objc_runtime
import lldb.formatters.metrics
import NSURL
import lldb.formatters.Logger

statistics = lldb.formatters.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 a summary for an NSURL, so they need not
# obey the interface specification for synthetic children providers
class NSBundleKnown_SummaryProvider:
	def adjust_for_architecture(self):
		pass

	def __init__(self, valobj, params):
		logger = lldb.formatters.Logger.Logger()
		self.valobj = valobj;
		self.sys_params = params
		if not(self.sys_params.types_cache.NSString):
			self.sys_params.types_cache.NSString = self.valobj.GetTarget().FindFirstType('NSString').GetPointerType()
		self.update();

	def update(self):
		logger = lldb.formatters.Logger.Logger()
		self.adjust_for_architecture();

	# we need to skip the ISA, plus four other values
	# that are luckily each a pointer in size
	# which makes our computation trivial :-)
	def offset(self):
		logger = lldb.formatters.Logger.Logger()
		return 5 * self.sys_params.pointer_size

	def url_text(self):
		logger = lldb.formatters.Logger.Logger()
		global statistics
		text = self.valobj.CreateChildAtOffset("text",
							self.offset(),
							self.sys_params.types_cache.NSString)
		my_string = text.GetSummary()
		if (my_string == None) or (my_string == ''):
			statistics.metric_hit('unknown_class',str(self.valobj.GetName()) + " triggered unkown pointer location")
			return NSBundleUnknown_SummaryProvider(self.valobj, self.sys_params).url_text()
		else:
			statistics.metric_hit('code_notrun',self.valobj)
			return my_string


class NSBundleUnknown_SummaryProvider:
	def adjust_for_architecture(self):
		pass

	def __init__(self, valobj, params):
		logger = lldb.formatters.Logger.Logger()
		self.valobj = valobj;
		self.sys_params = params
		self.update()

	def update(self):
		logger = lldb.formatters.Logger.Logger()
		self.adjust_for_architecture();

	def url_text(self):
		logger = lldb.formatters.Logger.Logger()
		stream = lldb.SBStream()
		self.valobj.GetExpressionPath(stream)
		expr = "(NSString*)[" + stream.GetData() + " bundlePath]"
		url_text_vo = self.valobj.CreateValueFromExpression("path",expr);
		if url_text_vo.IsValid():
			return url_text_vo.GetSummary()
		return '<variable is not NSBundle>'


def GetSummary_Impl(valobj):
	logger = lldb.formatters.Logger.Logger()
	global statistics
	class_data,wrapper =lldb.runtime.objc.objc_runtime.Utilities.prepare_class_detection(valobj,statistics)
	if wrapper:
		return wrapper
	
	name_string = class_data.class_name()
	logger >> "class name is: " + str(name_string)
	
	if name_string == 'NSBundle':
		wrapper = NSBundleKnown_SummaryProvider(valobj, class_data.sys_params)
		# [NSBundle mainBundle] does return an object that is
		# not correctly filled out for our purposes, so we still
		# end up having to run code in that case
		#statistics.metric_hit('code_notrun',valobj)
	else:
		wrapper = NSBundleUnknown_SummaryProvider(valobj, class_data.sys_params)
		statistics.metric_hit('unknown_class',valobj.GetName() + " seen as " + name_string)
	return wrapper;

def NSBundle_SummaryProvider (valobj,dict):
	logger = lldb.formatters.Logger.Logger()
	provider = GetSummary_Impl(valobj);
	if provider != None:
		if isinstance(provider,lldb.runtime.objc.objc_runtime.SpecialSituation_Description):
			return provider.message()
		try:
			summary = provider.url_text();
		except:
			summary = None
		logger >> "got summary " + str(summary)
		if summary == None or summary == '':
			summary = '<variable is not NSBundle>'
		return summary
	return 'Summary Unavailable'

def __lldb_init_module(debugger,dict):
	debugger.HandleCommand("type summary add -F NSBundle.NSBundle_SummaryProvider NSBundle")