1 //===-- NSException.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-exception
6 //
7 //===----------------------------------------------------------------------===//
8
9 #include "clang/AST/DeclCXX.h"
10
11 #include "Cocoa.h"
12
13 #include "lldb/Core/ValueObject.h"
14 #include "lldb/Core/ValueObjectConstResult.h"
15 #include "lldb/DataFormatters/FormattersHelpers.h"
16 #include "lldb/Target/Target.h"
17 #include "lldb/Utility/DataBufferHeap.h"
18 #include "lldb/Utility/Endian.h"
19 #include "lldb/Utility/Status.h"
20 #include "lldb/Utility/Stream.h"
21
22 #include "Plugins/Language/ObjC/NSString.h"
23 #include "Plugins/LanguageRuntime/ObjC/ObjCLanguageRuntime.h"
24 #include "Plugins/TypeSystem/Clang/TypeSystemClang.h"
25
26 using namespace lldb;
27 using namespace lldb_private;
28 using namespace lldb_private::formatters;
29
ExtractFields(ValueObject & valobj,ValueObjectSP * name_sp,ValueObjectSP * reason_sp,ValueObjectSP * userinfo_sp,ValueObjectSP * reserved_sp)30 static bool ExtractFields(ValueObject &valobj, ValueObjectSP *name_sp,
31 ValueObjectSP *reason_sp, ValueObjectSP *userinfo_sp,
32 ValueObjectSP *reserved_sp) {
33 ProcessSP process_sp(valobj.GetProcessSP());
34 if (!process_sp)
35 return false;
36
37 lldb::addr_t ptr = LLDB_INVALID_ADDRESS;
38
39 CompilerType valobj_type(valobj.GetCompilerType());
40 Flags type_flags(valobj_type.GetTypeInfo());
41 if (type_flags.AllClear(eTypeHasValue)) {
42 if (valobj.IsBaseClass() && valobj.GetParent())
43 ptr = valobj.GetParent()->GetValueAsUnsigned(LLDB_INVALID_ADDRESS);
44 } else {
45 ptr = valobj.GetValueAsUnsigned(LLDB_INVALID_ADDRESS);
46 }
47
48 if (ptr == LLDB_INVALID_ADDRESS)
49 return false;
50 size_t ptr_size = process_sp->GetAddressByteSize();
51
52 Status error;
53 auto name = process_sp->ReadPointerFromMemory(ptr + 1 * ptr_size, error);
54 if (error.Fail() || name == LLDB_INVALID_ADDRESS)
55 return false;
56 auto reason = process_sp->ReadPointerFromMemory(ptr + 2 * ptr_size, error);
57 if (error.Fail() || reason == LLDB_INVALID_ADDRESS)
58 return false;
59 auto userinfo = process_sp->ReadPointerFromMemory(ptr + 3 * ptr_size, error);
60 if (error.Fail() || userinfo == LLDB_INVALID_ADDRESS)
61 return false;
62 auto reserved = process_sp->ReadPointerFromMemory(ptr + 4 * ptr_size, error);
63 if (error.Fail() || reserved == LLDB_INVALID_ADDRESS)
64 return false;
65
66 InferiorSizedWord name_isw(name, *process_sp);
67 InferiorSizedWord reason_isw(reason, *process_sp);
68 InferiorSizedWord userinfo_isw(userinfo, *process_sp);
69 InferiorSizedWord reserved_isw(reserved, *process_sp);
70
71 TypeSystemClangSP scratch_ts_sp =
72 ScratchTypeSystemClang::GetForTarget(process_sp->GetTarget());
73 if (!scratch_ts_sp)
74 return false;
75
76 CompilerType voidstar =
77 scratch_ts_sp->GetBasicType(lldb::eBasicTypeVoid).GetPointerType();
78
79 if (name_sp)
80 *name_sp = ValueObject::CreateValueObjectFromData(
81 "name", name_isw.GetAsData(process_sp->GetByteOrder()),
82 valobj.GetExecutionContextRef(), voidstar);
83 if (reason_sp)
84 *reason_sp = ValueObject::CreateValueObjectFromData(
85 "reason", reason_isw.GetAsData(process_sp->GetByteOrder()),
86 valobj.GetExecutionContextRef(), voidstar);
87 if (userinfo_sp)
88 *userinfo_sp = ValueObject::CreateValueObjectFromData(
89 "userInfo", userinfo_isw.GetAsData(process_sp->GetByteOrder()),
90 valobj.GetExecutionContextRef(), voidstar);
91 if (reserved_sp)
92 *reserved_sp = ValueObject::CreateValueObjectFromData(
93 "reserved", reserved_isw.GetAsData(process_sp->GetByteOrder()),
94 valobj.GetExecutionContextRef(), voidstar);
95
96 return true;
97 }
98
NSException_SummaryProvider(ValueObject & valobj,Stream & stream,const TypeSummaryOptions & options)99 bool lldb_private::formatters::NSException_SummaryProvider(
100 ValueObject &valobj, Stream &stream, const TypeSummaryOptions &options) {
101 lldb::ValueObjectSP reason_sp;
102 if (!ExtractFields(valobj, nullptr, &reason_sp, nullptr, nullptr))
103 return false;
104
105 if (!reason_sp) {
106 stream.Printf("No reason");
107 return false;
108 }
109
110 StreamString reason_str_summary;
111 if (NSStringSummaryProvider(*reason_sp, reason_str_summary, options) &&
112 !reason_str_summary.Empty()) {
113 stream.Printf("%s", reason_str_summary.GetData());
114 return true;
115 } else
116 return false;
117 }
118
119 class NSExceptionSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
120 public:
NSExceptionSyntheticFrontEnd(lldb::ValueObjectSP valobj_sp)121 NSExceptionSyntheticFrontEnd(lldb::ValueObjectSP valobj_sp)
122 : SyntheticChildrenFrontEnd(*valobj_sp) {}
123
124 ~NSExceptionSyntheticFrontEnd() override = default;
125
CalculateNumChildren()126 llvm::Expected<uint32_t> CalculateNumChildren() override { return 4; }
127
GetChildAtIndex(uint32_t idx)128 lldb::ValueObjectSP GetChildAtIndex(uint32_t idx) override {
129 switch (idx) {
130 case 0: return m_name_sp;
131 case 1: return m_reason_sp;
132 case 2: return m_userinfo_sp;
133 case 3: return m_reserved_sp;
134 }
135 return lldb::ValueObjectSP();
136 }
137
Update()138 lldb::ChildCacheState Update() override {
139 m_name_sp.reset();
140 m_reason_sp.reset();
141 m_userinfo_sp.reset();
142 m_reserved_sp.reset();
143
144 const auto ret = ExtractFields(m_backend, &m_name_sp, &m_reason_sp,
145 &m_userinfo_sp, &m_reserved_sp);
146
147 return ret ? lldb::ChildCacheState::eReuse
148 : lldb::ChildCacheState::eRefetch;
149 }
150
MightHaveChildren()151 bool MightHaveChildren() override { return true; }
152
GetIndexOfChildWithName(ConstString name)153 size_t GetIndexOfChildWithName(ConstString name) override {
154 // NSException has 4 members:
155 // NSString *name;
156 // NSString *reason;
157 // NSDictionary *userInfo;
158 // id reserved;
159 static ConstString g_name("name");
160 static ConstString g_reason("reason");
161 static ConstString g_userInfo("userInfo");
162 static ConstString g_reserved("reserved");
163 if (name == g_name) return 0;
164 if (name == g_reason) return 1;
165 if (name == g_userInfo) return 2;
166 if (name == g_reserved) return 3;
167 return UINT32_MAX;
168 }
169
170 private:
171 ValueObjectSP m_name_sp;
172 ValueObjectSP m_reason_sp;
173 ValueObjectSP m_userinfo_sp;
174 ValueObjectSP m_reserved_sp;
175 };
176
177 SyntheticChildrenFrontEnd *
NSExceptionSyntheticFrontEndCreator(CXXSyntheticChildren *,lldb::ValueObjectSP valobj_sp)178 lldb_private::formatters::NSExceptionSyntheticFrontEndCreator(
179 CXXSyntheticChildren *, lldb::ValueObjectSP valobj_sp) {
180 lldb::ProcessSP process_sp(valobj_sp->GetProcessSP());
181 if (!process_sp)
182 return nullptr;
183 ObjCLanguageRuntime *runtime = ObjCLanguageRuntime::Get(*process_sp);
184 if (!runtime)
185 return nullptr;
186
187 ObjCLanguageRuntime::ClassDescriptorSP descriptor(
188 runtime->GetClassDescriptor(*valobj_sp.get()));
189
190 if (!descriptor.get() || !descriptor->IsValid())
191 return nullptr;
192
193 const char *class_name = descriptor->GetClassName().GetCString();
194
195 if (!class_name || !*class_name)
196 return nullptr;
197
198 if (!strcmp(class_name, "NSException"))
199 return (new NSExceptionSyntheticFrontEnd(valobj_sp));
200 else if (!strcmp(class_name, "NSCFException"))
201 return (new NSExceptionSyntheticFrontEnd(valobj_sp));
202 else if (!strcmp(class_name, "__NSCFException"))
203 return (new NSExceptionSyntheticFrontEnd(valobj_sp));
204
205 return nullptr;
206 }
207