215 lines · cpp
1//===-- NSError.cpp -------------------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9#include "clang/AST/DeclCXX.h"10 11#include "Cocoa.h"12 13#include "Plugins/TypeSystem/Clang/TypeSystemClang.h"14#include "lldb/DataFormatters/FormattersHelpers.h"15#include "lldb/Target/Target.h"16#include "lldb/Utility/DataBufferHeap.h"17#include "lldb/Utility/Endian.h"18#include "lldb/Utility/Status.h"19#include "lldb/Utility/Stream.h"20#include "lldb/ValueObject/ValueObject.h"21#include "lldb/ValueObject/ValueObjectConstResult.h"22 23#include "Plugins/Language/ObjC/NSString.h"24#include "Plugins/LanguageRuntime/ObjC/ObjCLanguageRuntime.h"25 26using namespace lldb;27using namespace lldb_private;28using namespace lldb_private::formatters;29 30static lldb::addr_t DerefToNSErrorPointer(ValueObject &valobj) {31 CompilerType valobj_type(valobj.GetCompilerType());32 Flags type_flags(valobj_type.GetTypeInfo());33 if (type_flags.AllClear(eTypeHasValue)) {34 if (valobj.IsBaseClass() && valobj.GetParent())35 return valobj.GetParent()->GetValueAsUnsigned(LLDB_INVALID_ADDRESS);36 } else {37 lldb::addr_t ptr_value = valobj.GetValueAsUnsigned(LLDB_INVALID_ADDRESS);38 if (type_flags.AllSet(eTypeIsPointer)) {39 CompilerType pointee_type(valobj_type.GetPointeeType());40 Flags pointee_flags(pointee_type.GetTypeInfo());41 if (pointee_flags.AllSet(eTypeIsPointer)) {42 if (ProcessSP process_sp = valobj.GetProcessSP()) {43 Status error;44 ptr_value = process_sp->ReadPointerFromMemory(ptr_value, error);45 }46 }47 }48 return ptr_value;49 }50 51 return LLDB_INVALID_ADDRESS;52}53 54bool lldb_private::formatters::NSError_SummaryProvider(55 ValueObject &valobj, Stream &stream, const TypeSummaryOptions &options) {56 ProcessSP process_sp(valobj.GetProcessSP());57 if (!process_sp)58 return false;59 60 lldb::addr_t ptr_value = DerefToNSErrorPointer(valobj);61 if (ptr_value == LLDB_INVALID_ADDRESS)62 return false;63 64 size_t ptr_size = process_sp->GetAddressByteSize();65 lldb::addr_t code_location = ptr_value + 2 * ptr_size;66 lldb::addr_t domain_location = ptr_value + 3 * ptr_size;67 68 Status error;69 int64_t code = process_sp->ReadSignedIntegerFromMemory(code_location,70 ptr_size, 0, error);71 if (error.Fail())72 return false;73 74 lldb::addr_t domain_str_value =75 process_sp->ReadPointerFromMemory(domain_location, error);76 if (error.Fail() || domain_str_value == LLDB_INVALID_ADDRESS)77 return false;78 79 if (!domain_str_value) {80 stream.Printf("domain: nil - code: %" PRIi64, code);81 return true;82 }83 84 InferiorSizedWord isw(domain_str_value, *process_sp);85 TypeSystemClangSP scratch_ts_sp =86 ScratchTypeSystemClang::GetForTarget(process_sp->GetTarget());87 88 if (!scratch_ts_sp)89 return false;90 ValueObjectSP domain_str_sp = ValueObject::CreateValueObjectFromData(91 "domain_str", isw.GetAsData(process_sp->GetByteOrder()),92 valobj.GetExecutionContextRef(),93 scratch_ts_sp->GetBasicType(lldb::eBasicTypeVoid).GetPointerType());94 95 if (!domain_str_sp)96 return false;97 98 StreamString domain_str_summary;99 if (NSStringSummaryProvider(*domain_str_sp, domain_str_summary, options) &&100 !domain_str_summary.Empty()) {101 stream.Printf("domain: %s - code: %" PRIi64, domain_str_summary.GetData(),102 code);103 return true;104 } else {105 stream.Printf("domain: nil - code: %" PRIi64, code);106 return true;107 }108}109 110class NSErrorSyntheticFrontEnd : public SyntheticChildrenFrontEnd {111public:112 NSErrorSyntheticFrontEnd(lldb::ValueObjectSP valobj_sp)113 : SyntheticChildrenFrontEnd(*valobj_sp) {}114 115 ~NSErrorSyntheticFrontEnd() override = default;116 // no need to delete m_child_ptr - it's kept alive by the cluster manager on117 // our behalf118 119 llvm::Expected<uint32_t> CalculateNumChildren() override {120 if (m_child_ptr)121 return 1;122 if (m_child_sp)123 return 1;124 return 0;125 }126 127 lldb::ValueObjectSP GetChildAtIndex(uint32_t idx) override {128 if (idx != 0)129 return lldb::ValueObjectSP();130 131 if (m_child_ptr)132 return m_child_ptr->GetSP();133 return m_child_sp;134 }135 136 lldb::ChildCacheState Update() override {137 m_child_ptr = nullptr;138 m_child_sp.reset();139 140 ProcessSP process_sp(m_backend.GetProcessSP());141 if (!process_sp)142 return lldb::ChildCacheState::eRefetch;143 144 lldb::addr_t userinfo_location = DerefToNSErrorPointer(m_backend);145 if (userinfo_location == LLDB_INVALID_ADDRESS)146 return lldb::ChildCacheState::eRefetch;147 148 size_t ptr_size = process_sp->GetAddressByteSize();149 150 userinfo_location += 4 * ptr_size;151 Status error;152 lldb::addr_t userinfo =153 process_sp->ReadPointerFromMemory(userinfo_location, error);154 if (userinfo == LLDB_INVALID_ADDRESS || error.Fail())155 return lldb::ChildCacheState::eRefetch;156 InferiorSizedWord isw(userinfo, *process_sp);157 TypeSystemClangSP scratch_ts_sp =158 ScratchTypeSystemClang::GetForTarget(process_sp->GetTarget());159 if (!scratch_ts_sp)160 return lldb::ChildCacheState::eRefetch;161 m_child_sp = CreateValueObjectFromData(162 "_userInfo", isw.GetAsData(process_sp->GetByteOrder()),163 m_backend.GetExecutionContextRef(),164 scratch_ts_sp->GetBasicType(lldb::eBasicTypeObjCID));165 return lldb::ChildCacheState::eRefetch;166 }167 168 llvm::Expected<size_t> GetIndexOfChildWithName(ConstString name) override {169 static ConstString g_userInfo("_userInfo");170 if (name == g_userInfo)171 return 0;172 return llvm::createStringError("Type has no child named '%s'",173 name.AsCString());174 }175 176private:177 // the child here can be "real" (i.e. an actual child of the root) or178 // synthetized from raw memory if the former, I need to store a plain pointer179 // to it - or else a loop of references will cause this entire hierarchy of180 // values to leak if the latter, then I need to store a SharedPointer to it -181 // so that it only goes away when everyone else in the cluster goes away oh182 // joy!183 ValueObject *m_child_ptr = nullptr;184 ValueObjectSP m_child_sp;185};186 187SyntheticChildrenFrontEnd *188lldb_private::formatters::NSErrorSyntheticFrontEndCreator(189 CXXSyntheticChildren *, lldb::ValueObjectSP valobj_sp) {190 lldb::ProcessSP process_sp(valobj_sp->GetProcessSP());191 if (!process_sp)192 return nullptr;193 ObjCLanguageRuntime *runtime = ObjCLanguageRuntime::Get(*process_sp);194 if (!runtime)195 return nullptr;196 197 ObjCLanguageRuntime::ClassDescriptorSP descriptor(198 runtime->GetClassDescriptor(*valobj_sp.get()));199 200 if (!descriptor.get() || !descriptor->IsValid())201 return nullptr;202 203 const char *class_name = descriptor->GetClassName().GetCString();204 205 if (!class_name || !*class_name)206 return nullptr;207 208 if (!strcmp(class_name, "NSError"))209 return (new NSErrorSyntheticFrontEnd(valobj_sp));210 else if (!strcmp(class_name, "__NSCFError"))211 return (new NSErrorSyntheticFrontEnd(valobj_sp));212 213 return nullptr;214}215