diff options
Diffstat (limited to 'examples/summaries/cocoa/objc_runtime.py')
-rw-r--r-- | examples/summaries/cocoa/objc_runtime.py | 781 |
1 files changed, 781 insertions, 0 deletions
diff --git a/examples/summaries/cocoa/objc_runtime.py b/examples/summaries/cocoa/objc_runtime.py new file mode 100644 index 000000000000..8b5debccb824 --- /dev/null +++ b/examples/summaries/cocoa/objc_runtime.py @@ -0,0 +1,781 @@ +""" +Objective-C runtime wrapper for use by LLDB Python formatters + +part of The LLVM Compiler Infrastructure +This file is distributed under the University of Illinois Open Source +License. See LICENSE.TXT for details. +""" +import lldb +import lldb.formatters.cache +import lldb.formatters.attrib_fromdict +import functools +import lldb.formatters.Logger + +class Utilities: + @staticmethod + def read_ascii(process, pointer,max_len=128): + logger = lldb.formatters.Logger.Logger() + error = lldb.SBError() + content = None + try: + content = process.ReadCStringFromMemory(pointer,max_len,error) + except: + pass + if content is None or len(content) == 0 or error.fail: + return None + return content + + @staticmethod + def is_valid_pointer(pointer, pointer_size, allow_tagged=0, allow_NULL=0): + logger = lldb.formatters.Logger.Logger() + if pointer is None: + return 0 + if pointer == 0: + return allow_NULL + if allow_tagged and (pointer % 2) == 1: + return 1 + return ((pointer % pointer_size) == 0) + + # Objective-C runtime has a rule that pointers in a class_t will only have bits 0 thru 46 set + # so if any pointer has bits 47 thru 63 high we know that this is not a valid isa + @staticmethod + def is_allowed_pointer(pointer): + logger = lldb.formatters.Logger.Logger() + if pointer is None: + return 0 + return ((pointer & 0xFFFF800000000000) == 0) + + @staticmethod + def read_child_of(valobj,offset,type): + logger = lldb.formatters.Logger.Logger() + if offset == 0 and type.GetByteSize() == valobj.GetByteSize(): + return valobj.GetValueAsUnsigned() + child = valobj.CreateChildAtOffset("childUNK",offset,type) + if child is None or child.IsValid() == 0: + return None; + return child.GetValueAsUnsigned() + + @staticmethod + def is_valid_identifier(name): + logger = lldb.formatters.Logger.Logger() + if name is None: + return None + if len(name) == 0: + return None + # technically, the ObjC runtime does not enforce any rules about what name a class can have + # in practice, the commonly used byte values for a class name are the letters, digits and some + # symbols: $, %, -, _, . + # WARNING: this means that you cannot use this runtime implementation if you need to deal + # with class names that use anything but what is allowed here + ok_values = dict.fromkeys("$%_.-ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz1234567890") + return all(c in ok_values for c in name) + + @staticmethod + def check_is_osx_lion(target): + logger = lldb.formatters.Logger.Logger() + # assume the only thing that has a Foundation.framework is a Mac + # assume anything < Lion does not even exist + try: + mod = target.module['Foundation'] + except: + mod = None + if mod is None or mod.IsValid() == 0: + return None + ver = mod.GetVersion() + if ver is None or ver == []: + return None + return (ver[0] < 900) + + # a utility method that factors out code common to almost all the formatters + # takes in an SBValue and a metrics object + # returns a class_data and a wrapper (or None, if the runtime alone can't decide on a wrapper) + @staticmethod + def prepare_class_detection(valobj,statistics): + logger = lldb.formatters.Logger.Logger() + class_data = ObjCRuntime(valobj) + if class_data.is_valid() == 0: + statistics.metric_hit('invalid_pointer',valobj) + wrapper = InvalidPointer_Description(valobj.GetValueAsUnsigned(0) == 0) + return class_data,wrapper + class_data = class_data.read_class_data() + if class_data.is_valid() == 0: + statistics.metric_hit('invalid_isa',valobj) + wrapper = InvalidISA_Description() + return class_data,wrapper + if class_data.is_kvo(): + class_data = class_data.get_superclass() + if class_data.class_name() == '_NSZombie_OriginalClass': + wrapper = ThisIsZombie_Description() + return class_data,wrapper + return class_data,None + + +class RoT_Data: + def __init__(self,rot_pointer,params): + logger = lldb.formatters.Logger.Logger() + if (Utilities.is_valid_pointer(rot_pointer.GetValueAsUnsigned(),params.pointer_size, allow_tagged=0)): + self.sys_params = params + self.valobj = rot_pointer + #self.flags = Utilities.read_child_of(self.valobj,0,self.sys_params.uint32_t) + #self.instanceStart = Utilities.read_child_of(self.valobj,4,self.sys_params.uint32_t) + self.instanceSize = None # lazy fetching + offset = 24 if self.sys_params.is_64_bit else 16 + #self.ivarLayoutPtr = Utilities.read_child_of(self.valobj,offset,self.sys_params.addr_ptr_type) + self.namePointer = Utilities.read_child_of(self.valobj,offset,self.sys_params.types_cache.addr_ptr_type) + self.valid = 1 # self.check_valid() + else: + logger >> "Marking as invalid - rot is invalid" + self.valid = 0 + if self.valid: + self.name = Utilities.read_ascii(self.valobj.GetTarget().GetProcess(),self.namePointer) + if not(Utilities.is_valid_identifier(self.name)): + logger >> "Marking as invalid - name is invalid" + self.valid = 0 + + # perform sanity checks on the contents of this class_ro_t + def check_valid(self): + self.valid = 1 + # misaligned pointers seem to be possible for this field + #if not(Utilities.is_valid_pointer(self.namePointer,self.sys_params.pointer_size,allow_tagged=0)): + # self.valid = 0 + # pass + + def __str__(self): + logger = lldb.formatters.Logger.Logger() + return \ + "instanceSize = " + hex(self.instance_size()) + "\n" + \ + "namePointer = " + hex(self.namePointer) + " --> " + self.name + + def is_valid(self): + return self.valid + + def instance_size(self,align=0): + logger = lldb.formatters.Logger.Logger() + if self.is_valid() == 0: + return None + if self.instanceSize is None: + self.instanceSize = Utilities.read_child_of(self.valobj,8,self.sys_params.types_cache.uint32_t) + if align: + unalign = self.instance_size(0) + if self.sys_params.is_64_bit: + return ((unalign + 7) & ~7) % 0x100000000 + else: + return ((unalign + 3) & ~3) % 0x100000000 + else: + return self.instanceSize + +class RwT_Data: + def __init__(self,rwt_pointer,params): + logger = lldb.formatters.Logger.Logger() + if (Utilities.is_valid_pointer(rwt_pointer.GetValueAsUnsigned(),params.pointer_size, allow_tagged=0)): + self.sys_params = params + self.valobj = rwt_pointer + #self.flags = Utilities.read_child_of(self.valobj,0,self.sys_params.uint32_t) + #self.version = Utilities.read_child_of(self.valobj,4,self.sys_params.uint32_t) + self.roPointer = Utilities.read_child_of(self.valobj,8,self.sys_params.types_cache.addr_ptr_type) + self.check_valid() + else: + logger >> "Marking as invalid - rwt is invald" + self.valid = 0 + if self.valid: + self.rot = self.valobj.CreateValueFromData("rot",lldb.SBData.CreateDataFromUInt64Array(self.sys_params.endianness, self.sys_params.pointer_size, [self.roPointer]),self.sys_params.types_cache.addr_ptr_type) +# self.rot = self.valobj.CreateValueFromAddress("rot",self.roPointer,self.sys_params.types_cache.addr_ptr_type).AddressOf() + self.data = RoT_Data(self.rot,self.sys_params) + + # perform sanity checks on the contents of this class_rw_t + def check_valid(self): + logger = lldb.formatters.Logger.Logger() + self.valid = 1 + if not(Utilities.is_valid_pointer(self.roPointer,self.sys_params.pointer_size,allow_tagged=0)): + logger >> "Marking as invalid - ropointer is invalid" + self.valid = 0 + + def __str__(self): + logger = lldb.formatters.Logger.Logger() + return \ + "roPointer = " + hex(self.roPointer) + + def is_valid(self): + logger = lldb.formatters.Logger.Logger() + if self.valid: + return self.data.is_valid() + return 0 + +class Class_Data_V2: + def __init__(self,isa_pointer,params): + logger = lldb.formatters.Logger.Logger() + if (isa_pointer != None) and (Utilities.is_valid_pointer(isa_pointer.GetValueAsUnsigned(),params.pointer_size, allow_tagged=0)): + self.sys_params = params + self.valobj = isa_pointer + self.check_valid() + else: + logger >> "Marking as invalid - isa is invalid or None" + self.valid = 0 + if self.valid: + self.rwt = self.valobj.CreateValueFromData("rwt",lldb.SBData.CreateDataFromUInt64Array(self.sys_params.endianness, self.sys_params.pointer_size, [self.dataPointer]),self.sys_params.types_cache.addr_ptr_type) +# self.rwt = self.valobj.CreateValueFromAddress("rwt",self.dataPointer,self.sys_params.types_cache.addr_ptr_type).AddressOf() + self.data = RwT_Data(self.rwt,self.sys_params) + + # perform sanity checks on the contents of this class_t + # this call tries to minimize the amount of data fetched- as soon as we have "proven" + # that we have an invalid object, we stop reading + def check_valid(self): + logger = lldb.formatters.Logger.Logger() + self.valid = 1 + + self.isaPointer = Utilities.read_child_of(self.valobj,0,self.sys_params.types_cache.addr_ptr_type) + if not(Utilities.is_valid_pointer(self.isaPointer,self.sys_params.pointer_size,allow_tagged=0)): + logger >> "Marking as invalid - isaPointer is invalid" + self.valid = 0 + return + if not(Utilities.is_allowed_pointer(self.isaPointer)): + logger >> "Marking as invalid - isaPointer is not allowed" + self.valid = 0 + return + + self.cachePointer = Utilities.read_child_of(self.valobj,2*self.sys_params.pointer_size,self.sys_params.types_cache.addr_ptr_type) + if not(Utilities.is_valid_pointer(self.cachePointer,self.sys_params.pointer_size,allow_tagged=0)): + logger >> "Marking as invalid - cachePointer is invalid" + self.valid = 0 + return + if not(Utilities.is_allowed_pointer(self.cachePointer)): + logger >> "Marking as invalid - cachePointer is not allowed" + self.valid = 0 + return + self.dataPointer = Utilities.read_child_of(self.valobj,4*self.sys_params.pointer_size,self.sys_params.types_cache.addr_ptr_type) + if not(Utilities.is_valid_pointer(self.dataPointer,self.sys_params.pointer_size,allow_tagged=0)): + logger >> "Marking as invalid - dataPointer is invalid" + self.valid = 0 + return + if not(Utilities.is_allowed_pointer(self.dataPointer)): + logger >> "Marking as invalid - dataPointer is not allowed" + self.valid = 0 + return + + self.superclassIsaPointer = Utilities.read_child_of(self.valobj,1*self.sys_params.pointer_size,self.sys_params.types_cache.addr_ptr_type) + if not(Utilities.is_valid_pointer(self.superclassIsaPointer,self.sys_params.pointer_size,allow_tagged=0, allow_NULL=1)): + logger >> "Marking as invalid - superclassIsa is invalid" + self.valid = 0 + return + if not(Utilities.is_allowed_pointer(self.superclassIsaPointer)): + logger >> "Marking as invalid - superclassIsa is not allowed" + self.valid = 0 + return + + # in general, KVO is implemented by transparently subclassing + # however, there could be exceptions where a class does something else + # internally to implement the feature - this method will have no clue that a class + # has been KVO'ed unless the standard implementation technique is used + def is_kvo(self): + logger = lldb.formatters.Logger.Logger() + if self.is_valid(): + if self.class_name().startswith("NSKVONotifying_"): + return 1 + return 0 + + # some CF classes have a valid ObjC isa in their CFRuntimeBase + # but instead of being class-specific this isa points to a match-'em-all class + # which is __NSCFType (the versions without __ also exists and we are matching to it + # just to be on the safe side) + def is_cftype(self): + logger = lldb.formatters.Logger.Logger() + if self.is_valid(): + return self.class_name() == '__NSCFType' or self.class_name() == 'NSCFType' + + def get_superclass(self): + logger = lldb.formatters.Logger.Logger() + if self.is_valid(): + parent_isa_pointer = self.valobj.CreateChildAtOffset("parent_isa", + self.sys_params.pointer_size, + self.sys_params.addr_ptr_type) + return Class_Data_V2(parent_isa_pointer,self.sys_params) + else: + return None + + def class_name(self): + logger = lldb.formatters.Logger.Logger() + if self.is_valid(): + return self.data.data.name + else: + return None + + def is_valid(self): + logger = lldb.formatters.Logger.Logger() + if self.valid: + return self.data.is_valid() + return 0 + + def __str__(self): + logger = lldb.formatters.Logger.Logger() + return 'isaPointer = ' + hex(self.isaPointer) + "\n" + \ + "superclassIsaPointer = " + hex(self.superclassIsaPointer) + "\n" + \ + "cachePointer = " + hex(self.cachePointer) + "\n" + \ + "data = " + hex(self.dataPointer) + + def is_tagged(self): + return 0 + + def instance_size(self,align=0): + logger = lldb.formatters.Logger.Logger() + if self.is_valid() == 0: + return None + return self.rwt.rot.instance_size(align) + +# runtime v1 is much less intricate than v2 and stores relevant information directly in the class_t object +class Class_Data_V1: + def __init__(self,isa_pointer,params): + logger = lldb.formatters.Logger.Logger() + if (isa_pointer != None) and (Utilities.is_valid_pointer(isa_pointer.GetValueAsUnsigned(),params.pointer_size, allow_tagged=0)): + self.valid = 1 + self.sys_params = params + self.valobj = isa_pointer + self.check_valid() + else: + logger >> "Marking as invalid - isaPointer is invalid or None" + self.valid = 0 + if self.valid: + self.name = Utilities.read_ascii(self.valobj.GetTarget().GetProcess(),self.namePointer) + if not(Utilities.is_valid_identifier(self.name)): + logger >> "Marking as invalid - name is not valid" + self.valid = 0 + + # perform sanity checks on the contents of this class_t + def check_valid(self): + logger = lldb.formatters.Logger.Logger() + self.valid = 1 + + self.isaPointer = Utilities.read_child_of(self.valobj,0,self.sys_params.types_cache.addr_ptr_type) + if not(Utilities.is_valid_pointer(self.isaPointer,self.sys_params.pointer_size,allow_tagged=0)): + logger >> "Marking as invalid - isaPointer is invalid" + self.valid = 0 + return + + self.superclassIsaPointer = Utilities.read_child_of(self.valobj,1*self.sys_params.pointer_size,self.sys_params.types_cache.addr_ptr_type) + if not(Utilities.is_valid_pointer(self.superclassIsaPointer,self.sys_params.pointer_size,allow_tagged=0,allow_NULL=1)): + logger >> "Marking as invalid - superclassIsa is invalid" + self.valid = 0 + return + + self.namePointer = Utilities.read_child_of(self.valobj,2*self.sys_params.pointer_size,self.sys_params.types_cache.addr_ptr_type) + #if not(Utilities.is_valid_pointer(self.namePointer,self.sys_params.pointer_size,allow_tagged=0,allow_NULL=0)): + # self.valid = 0 + # return + + # in general, KVO is implemented by transparently subclassing + # however, there could be exceptions where a class does something else + # internally to implement the feature - this method will have no clue that a class + # has been KVO'ed unless the standard implementation technique is used + def is_kvo(self): + logger = lldb.formatters.Logger.Logger() + if self.is_valid(): + if self.class_name().startswith("NSKVONotifying_"): + return 1 + return 0 + + # some CF classes have a valid ObjC isa in their CFRuntimeBase + # but instead of being class-specific this isa points to a match-'em-all class + # which is __NSCFType (the versions without __ also exists and we are matching to it + # just to be on the safe side) + def is_cftype(self): + logger = lldb.formatters.Logger.Logger() + if self.is_valid(): + return self.class_name() == '__NSCFType' or self.class_name() == 'NSCFType' + + def get_superclass(self): + logger = lldb.formatters.Logger.Logger() + if self.is_valid(): + parent_isa_pointer = self.valobj.CreateChildAtOffset("parent_isa", + self.sys_params.pointer_size, + self.sys_params.addr_ptr_type) + return Class_Data_V1(parent_isa_pointer,self.sys_params) + else: + return None + + def class_name(self): + logger = lldb.formatters.Logger.Logger() + if self.is_valid(): + return self.name + else: + return None + + def is_valid(self): + return self.valid + + def __str__(self): + logger = lldb.formatters.Logger.Logger() + return 'isaPointer = ' + hex(self.isaPointer) + "\n" + \ + "superclassIsaPointer = " + hex(self.superclassIsaPointer) + "\n" + \ + "namePointer = " + hex(self.namePointer) + " --> " + self.name + \ + "instanceSize = " + hex(self.instanceSize()) + "\n" + + def is_tagged(self): + return 0 + + def instance_size(self,align=0): + logger = lldb.formatters.Logger.Logger() + if self.is_valid() == 0: + return None + if self.instanceSize is None: + self.instanceSize = Utilities.read_child_of(self.valobj,5*self.sys_params.pointer_size,self.sys_params.types_cache.addr_ptr_type) + if align: + unalign = self.instance_size(0) + if self.sys_params.is_64_bit: + return ((unalign + 7) & ~7) % 0x100000000 + else: + return ((unalign + 3) & ~3) % 0x100000000 + else: + return self.instanceSize + +# these are the only tagged pointers values for current versions +# of OSX - they might change in future OS releases, and no-one is +# advised to rely on these values, or any of the bitmasking formulas +# in TaggedClass_Data. doing otherwise is at your own risk +TaggedClass_Values_Lion = {1 : 'NSNumber', \ + 5: 'NSManagedObject', \ + 6: 'NSDate', \ + 7: 'NSDateTS' }; +TaggedClass_Values_NMOS = {0: 'NSAtom', \ + 3 : 'NSNumber', \ + 4: 'NSDateTS', \ + 5: 'NSManagedObject', \ + 6: 'NSDate' }; + +class TaggedClass_Data: + def __init__(self,pointer,params): + logger = lldb.formatters.Logger.Logger() + global TaggedClass_Values_Lion,TaggedClass_Values_NMOS + self.valid = 1 + self.name = None + self.sys_params = params + self.valobj = pointer + self.val = (pointer & ~0x0000000000000000FF) >> 8 + self.class_bits = (pointer & 0xE) >> 1 + self.i_bits = (pointer & 0xF0) >> 4 + + if self.sys_params.is_lion: + if self.class_bits in TaggedClass_Values_Lion: + self.name = TaggedClass_Values_Lion[self.class_bits] + else: + logger >> "Marking as invalid - not a good tagged pointer for Lion" + self.valid = 0 + else: + if self.class_bits in TaggedClass_Values_NMOS: + self.name = TaggedClass_Values_NMOS[self.class_bits] + else: + logger >> "Marking as invalid - not a good tagged pointer for NMOS" + self.valid = 0 + + + def is_valid(self): + return self.valid + + def class_name(self): + logger = lldb.formatters.Logger.Logger() + if self.is_valid(): + return self.name + else: + return 0 + + def value(self): + return self.val if self.is_valid() else None + + def info_bits(self): + return self.i_bits if self.is_valid() else None + + def is_kvo(self): + return 0 + + def is_cftype(self): + return 0 + + # we would need to go around looking for the superclass or ask the runtime + # for now, we seem not to require support for this operation so we will merrily + # pretend to be at a root point in the hierarchy + def get_superclass(self): + return None + + # anything that is handled here is tagged + def is_tagged(self): + return 1 + + # it seems reasonable to say that a tagged pointer is the size of a pointer + def instance_size(self,align=0): + logger = lldb.formatters.Logger.Logger() + if self.is_valid() == 0: + return None + return self.sys_params.pointer_size + + +class InvalidClass_Data: + def __init__(self): + pass + def is_valid(self): + return 0 + + +class Version: + def __init__(self, major, minor, release, build_string): + self._major = major + self._minor = minor + self._release = release + self._build_string = build_string + + def get_major(self): + return self._major + def get_minor(self): + return self._minor + def get_release(self): + return self._release + def get_build_string(self): + return self._build_string + + major = property(get_major,None) + minor = property(get_minor,None) + release = property(get_release,None) + build_string = property(get_build_string,None) + + def __lt__(self,other): + if (self.major < other.major): + return 1 + if (self.minor < other.minor): + return 1 + if (self.release < other.release): + return 1 + # build strings are not compared since they are heavily platform-dependent and might not always + # be available + return 0 + + def __eq__(self,other): + return (self.major == other.major) and \ + (self.minor == other.minor) and \ + (self.release == other.release) and \ + (self.build_string == other.build_string) + + # Python 2.6 doesn't have functools.total_ordering, so we have to implement + # other comparators + def __gt__(self, other): + return other < self + + def __le__(self, other): + return not other < self + + def __ge__(self, other): + return not self < other + + +runtime_version = lldb.formatters.cache.Cache() +os_version = lldb.formatters.cache.Cache() +types_caches = lldb.formatters.cache.Cache() +isa_caches = lldb.formatters.cache.Cache() + +class SystemParameters: + def __init__(self,valobj): + logger = lldb.formatters.Logger.Logger() + self.adjust_for_architecture(valobj) + self.adjust_for_process(valobj) + + def adjust_for_process(self, valobj): + logger = lldb.formatters.Logger.Logger() + global runtime_version + global os_version + global types_caches + global isa_caches + + process = valobj.GetTarget().GetProcess() + self.pid = process.GetUniqueID() # using the unique ID for added guarantees (see svn revision 172628 for further details) + + if runtime_version.look_for_key(self.pid): + self.runtime_version = runtime_version.get_value(self.pid) + else: + self.runtime_version = ObjCRuntime.runtime_version(process) + runtime_version.add_item(self.pid,self.runtime_version) + + if os_version.look_for_key(self.pid): + self.is_lion = os_version.get_value(self.pid) + else: + self.is_lion = Utilities.check_is_osx_lion(valobj.GetTarget()) + os_version.add_item(self.pid,self.is_lion) + + if types_caches.look_for_key(self.pid): + self.types_cache = types_caches.get_value(self.pid) + else: + self.types_cache = lldb.formatters.attrib_fromdict.AttributesDictionary(allow_reset=0) + self.types_cache.addr_type = valobj.GetType().GetBasicType(lldb.eBasicTypeUnsignedLong) + self.types_cache.addr_ptr_type = self.types_cache.addr_type.GetPointerType() + self.types_cache.uint32_t = valobj.GetType().GetBasicType(lldb.eBasicTypeUnsignedInt) + types_caches.add_item(self.pid,self.types_cache) + + if isa_caches.look_for_key(self.pid): + self.isa_cache = isa_caches.get_value(self.pid) + else: + self.isa_cache = lldb.formatters.cache.Cache() + isa_caches.add_item(self.pid,self.isa_cache) + + def adjust_for_architecture(self,valobj): + process = valobj.GetTarget().GetProcess() + self.pointer_size = process.GetAddressByteSize() + self.is_64_bit = (self.pointer_size == 8) + self.endianness = process.GetByteOrder() + self.is_little = (self.endianness == lldb.eByteOrderLittle) + self.cfruntime_size = 16 if self.is_64_bit else 8 + + # a simple helper function that makes it more explicit that one is calculating + # an offset that is made up of X pointers and Y bytes of additional data + # taking into account pointer size - if you know there is going to be some padding + # you can pass that in and it will be taken into account (since padding may be different between + # 32 and 64 bit versions, you can pass padding value for both, the right one will be used) + def calculate_offset(self, num_pointers = 0, bytes_count = 0, padding32 = 0, padding64 = 0): + value = bytes_count + num_pointers*self.pointer_size + return value + padding64 if self.is_64_bit else value + padding32 + +class ObjCRuntime: + + # the ObjC runtime has no explicit "version" field that we can use + # instead, we discriminate v1 from v2 by looking for the presence + # of a well-known section only present in v1 + @staticmethod + def runtime_version(process): + logger = lldb.formatters.Logger.Logger() + if process.IsValid() == 0: + logger >> "No process - bailing out" + return None + target = process.GetTarget() + num_modules = target.GetNumModules() + module_objc = None + for idx in range(num_modules): + module = target.GetModuleAtIndex(idx) + if module.GetFileSpec().GetFilename() == 'libobjc.A.dylib': + module_objc = module + break + if module_objc is None or module_objc.IsValid() == 0: + logger >> "no libobjc - bailing out" + return None + num_sections = module.GetNumSections() + section_objc = None + for idx in range(num_sections): + section = module.GetSectionAtIndex(idx) + if section.GetName() == '__OBJC': + section_objc = section + break + if section_objc != None and section_objc.IsValid(): + logger >> "found __OBJC: v1" + return 1 + logger >> "no __OBJC: v2" + return 2 + + @staticmethod + def runtime_from_isa(isa): + logger = lldb.formatters.Logger.Logger() + runtime = ObjCRuntime(isa) + runtime.isa = isa + return runtime + + def __init__(self,valobj): + logger = lldb.formatters.Logger.Logger() + self.valobj = valobj + self.adjust_for_architecture() + self.sys_params = SystemParameters(self.valobj) + self.unsigned_value = self.valobj.GetValueAsUnsigned() + self.isa_value = None + + def adjust_for_architecture(self): + pass + +# an ObjC pointer can either be tagged or must be aligned + def is_tagged(self): + logger = lldb.formatters.Logger.Logger() + if self.valobj is None: + return 0 + return (Utilities.is_valid_pointer(self.unsigned_value,self.sys_params.pointer_size, allow_tagged=1) and \ + not(Utilities.is_valid_pointer(self.unsigned_value,self.sys_params.pointer_size, allow_tagged=0))) + + def is_valid(self): + logger = lldb.formatters.Logger.Logger() + if self.valobj is None: + return 0 + if self.valobj.IsInScope() == 0: + return 0 + return Utilities.is_valid_pointer(self.unsigned_value,self.sys_params.pointer_size, allow_tagged=1) + + def is_nil(self): + return self.unsigned_value == 0 + + def read_isa(self): + logger = lldb.formatters.Logger.Logger() + if self.isa_value != None: + logger >> "using cached isa" + return self.isa_value + self.isa_pointer = self.valobj.CreateChildAtOffset("cfisa", + 0, + self.sys_params.types_cache.addr_ptr_type) + if self.isa_pointer is None or self.isa_pointer.IsValid() == 0: + logger >> "invalid isa - bailing out" + return None; + self.isa_value = self.isa_pointer.GetValueAsUnsigned(1) + if self.isa_value == 1: + logger >> "invalid isa value - bailing out" + return None; + return Ellipsis + + def read_class_data(self): + logger = lldb.formatters.Logger.Logger() + global isa_cache + if self.is_tagged(): + # tagged pointers only exist in ObjC v2 + if self.sys_params.runtime_version == 2: + logger >> "on v2 and tagged - maybe" + # not every odd-valued pointer is actually tagged. most are just plain wrong + # we could try and predetect this before even creating a TaggedClass_Data object + # but unless performance requires it, this seems a cleaner way to tackle the task + tentative_tagged = TaggedClass_Data(self.unsigned_value,self.sys_params) + if tentative_tagged.is_valid(): + logger >> "truly tagged" + return tentative_tagged + else: + logger >> "not tagged - error" + return InvalidClass_Data() + else: + logger >> "on v1 and tagged - error" + return InvalidClass_Data() + if self.is_valid() == 0 or self.read_isa() is None: + return InvalidClass_Data() + data = self.sys_params.isa_cache.get_value(self.isa_value,default=None) + if data != None: + return data + if self.sys_params.runtime_version == 2: + data = Class_Data_V2(self.isa_pointer,self.sys_params) + else: + data = Class_Data_V1(self.isa_pointer,self.sys_params) + if data is None: + return InvalidClass_Data() + if data.is_valid(): + self.sys_params.isa_cache.add_item(self.isa_value,data,ok_to_replace=1) + return data + +# these classes below can be used by the data formatters to provide a consistent message that describes a given runtime-generated situation +class SpecialSituation_Description: + def message(self): + return '' + +class InvalidPointer_Description(SpecialSituation_Description): + + def __init__(self,nil): + self.is_nil = nil + + def message(self): + if self.is_nil: + return '@"<nil>"' + else: + return '<invalid pointer>' + +class InvalidISA_Description(SpecialSituation_Description): + + def __init__(self): + pass + + def message(self): + return '<not an Objective-C object>' + +class ThisIsZombie_Description(SpecialSituation_Description): + def message(self): + return '<freed object>'
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