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/DataFormatters/FormattersHelpers.h"
14#include "lldb/Target/Target.h"
15#include "lldb/Utility/DataBufferHeap.h"
16#include "lldb/Utility/Endian.h"
17#include "lldb/Utility/Status.h"
18#include "lldb/Utility/Stream.h"
19#include "lldb/ValueObject/ValueObject.h"
20#include "lldb/ValueObject/ValueObjectConstResult.h"
21
22#include "Plugins/Language/ObjC/NSString.h"
23#include "Plugins/LanguageRuntime/ObjC/ObjCLanguageRuntime.h"
24#include "Plugins/TypeSystem/Clang/TypeSystemClang.h"
25
26using namespace lldb;
27using namespace lldb_private;
28using namespace lldb_private::formatters;
29
30static 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(mask: 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(vm_addr: ptr + 1 * ptr_size, error);
54 if (error.Fail() || name == LLDB_INVALID_ADDRESS)
55 return false;
56 auto reason = process_sp->ReadPointerFromMemory(vm_addr: ptr + 2 * ptr_size, error);
57 if (error.Fail() || reason == LLDB_INVALID_ADDRESS)
58 return false;
59 auto userinfo = process_sp->ReadPointerFromMemory(vm_addr: ptr + 3 * ptr_size, error);
60 if (error.Fail() || userinfo == LLDB_INVALID_ADDRESS)
61 return false;
62 auto reserved = process_sp->ReadPointerFromMemory(vm_addr: 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(target&: process_sp->GetTarget());
73 if (!scratch_ts_sp)
74 return false;
75
76 CompilerType voidstar =
77 scratch_ts_sp->GetBasicType(type: lldb::eBasicTypeVoid).GetPointerType();
78
79 if (name_sp)
80 *name_sp = ValueObject::CreateValueObjectFromData(
81 name: "name", data: name_isw.GetAsData(byte_order: process_sp->GetByteOrder()),
82 exe_ctx: valobj.GetExecutionContextRef(), type: voidstar);
83 if (reason_sp)
84 *reason_sp = ValueObject::CreateValueObjectFromData(
85 name: "reason", data: reason_isw.GetAsData(byte_order: process_sp->GetByteOrder()),
86 exe_ctx: valobj.GetExecutionContextRef(), type: voidstar);
87 if (userinfo_sp)
88 *userinfo_sp = ValueObject::CreateValueObjectFromData(
89 name: "userInfo", data: userinfo_isw.GetAsData(byte_order: process_sp->GetByteOrder()),
90 exe_ctx: valobj.GetExecutionContextRef(), type: voidstar);
91 if (reserved_sp)
92 *reserved_sp = ValueObject::CreateValueObjectFromData(
93 name: "reserved", data: reserved_isw.GetAsData(byte_order: process_sp->GetByteOrder()),
94 exe_ctx: valobj.GetExecutionContextRef(), type: voidstar);
95
96 return true;
97}
98
99bool lldb_private::formatters::NSException_SummaryProvider(
100 ValueObject &valobj, Stream &stream, const TypeSummaryOptions &options) {
101 lldb::ValueObjectSP reason_sp;
102 if (!ExtractFields(valobj, name_sp: nullptr, reason_sp: &reason_sp, userinfo_sp: nullptr, reserved_sp: nullptr))
103 return false;
104
105 if (!reason_sp) {
106 stream.Printf(format: "No reason");
107 return false;
108 }
109
110 StreamString reason_str_summary;
111 if (NSStringSummaryProvider(valobj&: *reason_sp, stream&: reason_str_summary, options) &&
112 !reason_str_summary.Empty()) {
113 stream.Printf(format: "%s", reason_str_summary.GetData());
114 return true;
115 } else
116 return false;
117}
118
119class NSExceptionSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
120public:
121 NSExceptionSyntheticFrontEnd(lldb::ValueObjectSP valobj_sp)
122 : SyntheticChildrenFrontEnd(*valobj_sp) {}
123
124 ~NSExceptionSyntheticFrontEnd() override = default;
125
126 llvm::Expected<uint32_t> CalculateNumChildren() override { return 4; }
127
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
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(valobj&: m_backend, name_sp: &m_name_sp, reason_sp: &m_reason_sp,
145 userinfo_sp: &m_userinfo_sp, reserved_sp: &m_reserved_sp);
146
147 return ret ? lldb::ChildCacheState::eReuse
148 : lldb::ChildCacheState::eRefetch;
149 }
150
151 llvm::Expected<size_t> GetIndexOfChildWithName(ConstString name) override {
152 // NSException has 4 members:
153 // NSString *name;
154 // NSString *reason;
155 // NSDictionary *userInfo;
156 // id reserved;
157 static ConstString g_name("name");
158 static ConstString g_reason("reason");
159 static ConstString g_userInfo("userInfo");
160 static ConstString g_reserved("reserved");
161 if (name == g_name) return 0;
162 if (name == g_reason) return 1;
163 if (name == g_userInfo) return 2;
164 if (name == g_reserved) return 3;
165 return llvm::createStringError(Fmt: "Type has no child named '%s'",
166 Vals: name.AsCString());
167 }
168
169private:
170 ValueObjectSP m_name_sp;
171 ValueObjectSP m_reason_sp;
172 ValueObjectSP m_userinfo_sp;
173 ValueObjectSP m_reserved_sp;
174};
175
176SyntheticChildrenFrontEnd *
177lldb_private::formatters::NSExceptionSyntheticFrontEndCreator(
178 CXXSyntheticChildren *, lldb::ValueObjectSP valobj_sp) {
179 lldb::ProcessSP process_sp(valobj_sp->GetProcessSP());
180 if (!process_sp)
181 return nullptr;
182 ObjCLanguageRuntime *runtime = ObjCLanguageRuntime::Get(process&: *process_sp);
183 if (!runtime)
184 return nullptr;
185
186 ObjCLanguageRuntime::ClassDescriptorSP descriptor(
187 runtime->GetClassDescriptor(in_value&: *valobj_sp.get()));
188
189 if (!descriptor.get() || !descriptor->IsValid())
190 return nullptr;
191
192 const char *class_name = descriptor->GetClassName().GetCString();
193
194 if (!class_name || !*class_name)
195 return nullptr;
196
197 if (!strcmp(s1: class_name, s2: "NSException"))
198 return (new NSExceptionSyntheticFrontEnd(valobj_sp));
199 else if (!strcmp(s1: class_name, s2: "NSCFException"))
200 return (new NSExceptionSyntheticFrontEnd(valobj_sp));
201 else if (!strcmp(s1: class_name, s2: "__NSCFException"))
202 return (new NSExceptionSyntheticFrontEnd(valobj_sp));
203
204 return nullptr;
205}
206

source code of lldb/source/Plugins/Language/ObjC/NSException.cpp