1 //===-- ObjectContainerUniversalMachO.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 "ObjectContainerUniversalMachO.h"
10 #include "lldb/Core/Module.h"
11 #include "lldb/Core/ModuleSpec.h"
12 #include "lldb/Core/PluginManager.h"
13 #include "lldb/Symbol/ObjectFile.h"
14 #include "lldb/Target/Target.h"
15 #include "lldb/Utility/ArchSpec.h"
16 #include "lldb/Utility/DataBuffer.h"
17 #include "lldb/Utility/Stream.h"
18
19 using namespace lldb;
20 using namespace lldb_private;
21 using namespace llvm::MachO;
22
LLDB_PLUGIN_DEFINE_ADV(ObjectContainerUniversalMachO,ObjectContainerMachOArchive)23 LLDB_PLUGIN_DEFINE_ADV(ObjectContainerUniversalMachO,
24 ObjectContainerMachOArchive)
25
26 void ObjectContainerUniversalMachO::Initialize() {
27 PluginManager::RegisterPlugin(GetPluginNameStatic(),
28 GetPluginDescriptionStatic(), CreateInstance,
29 GetModuleSpecifications);
30 }
31
Terminate()32 void ObjectContainerUniversalMachO::Terminate() {
33 PluginManager::UnregisterPlugin(CreateInstance);
34 }
35
CreateInstance(const lldb::ModuleSP & module_sp,DataBufferSP & data_sp,lldb::offset_t data_offset,const FileSpec * file,lldb::offset_t file_offset,lldb::offset_t length)36 ObjectContainer *ObjectContainerUniversalMachO::CreateInstance(
37 const lldb::ModuleSP &module_sp, DataBufferSP &data_sp,
38 lldb::offset_t data_offset, const FileSpec *file,
39 lldb::offset_t file_offset, lldb::offset_t length) {
40 // We get data when we aren't trying to look for cached container
41 // information, so only try and look for an architecture slice if we get data
42 if (data_sp) {
43 DataExtractor data;
44 data.SetData(data_sp, data_offset, length);
45 if (ObjectContainerUniversalMachO::MagicBytesMatch(data)) {
46 std::unique_ptr<ObjectContainerUniversalMachO> container_up(
47 new ObjectContainerUniversalMachO(module_sp, data_sp, data_offset,
48 file, file_offset, length));
49 if (container_up->ParseHeader()) {
50 return container_up.release();
51 }
52 }
53 }
54 return nullptr;
55 }
56
MagicBytesMatch(const DataExtractor & data)57 bool ObjectContainerUniversalMachO::MagicBytesMatch(const DataExtractor &data) {
58 lldb::offset_t offset = 0;
59 uint32_t magic = data.GetU32(&offset);
60 return magic == FAT_MAGIC || magic == FAT_CIGAM || magic == FAT_MAGIC_64 ||
61 magic == FAT_CIGAM_64;
62 }
63
ObjectContainerUniversalMachO(const lldb::ModuleSP & module_sp,DataBufferSP & data_sp,lldb::offset_t data_offset,const FileSpec * file,lldb::offset_t file_offset,lldb::offset_t length)64 ObjectContainerUniversalMachO::ObjectContainerUniversalMachO(
65 const lldb::ModuleSP &module_sp, DataBufferSP &data_sp,
66 lldb::offset_t data_offset, const FileSpec *file,
67 lldb::offset_t file_offset, lldb::offset_t length)
68 : ObjectContainer(module_sp, file, file_offset, length, data_sp,
69 data_offset),
70 m_header(), m_fat_archs() {
71 memset(&m_header, 0, sizeof(m_header));
72 }
73
74 ObjectContainerUniversalMachO::~ObjectContainerUniversalMachO() = default;
75
ParseHeader()76 bool ObjectContainerUniversalMachO::ParseHeader() {
77 bool success = ParseHeader(m_data, m_header, m_fat_archs);
78 // We no longer need any data, we parsed all we needed to parse and cached it
79 // in m_header and m_fat_archs
80 m_data.Clear();
81 return success;
82 }
83
ParseHeader(lldb_private::DataExtractor & data,llvm::MachO::fat_header & header,std::vector<FatArch> & fat_archs)84 bool ObjectContainerUniversalMachO::ParseHeader(
85 lldb_private::DataExtractor &data, llvm::MachO::fat_header &header,
86 std::vector<FatArch> &fat_archs) {
87 // Store the file offset for this universal file as we could have a universal
88 // .o file in a BSD archive, or be contained in another kind of object.
89 lldb::offset_t offset = 0;
90 data.SetByteOrder(eByteOrderBig);
91 header.magic = data.GetU32(&offset);
92 fat_archs.clear();
93
94 // Universal mach-o files always have their headers in big endian.
95 if (header.magic == FAT_MAGIC || header.magic == FAT_MAGIC_64) {
96 const bool is_fat64 = header.magic == FAT_MAGIC_64;
97 data.SetAddressByteSize(is_fat64 ? 8 : 4);
98
99 header.nfat_arch = data.GetU32(&offset);
100
101 // Now we should have enough data for all of the fat headers, so lets index
102 // them so we know how many architectures that this universal binary
103 // contains.
104 for (uint32_t arch_idx = 0; arch_idx < header.nfat_arch; ++arch_idx) {
105 if (data.ValidOffsetForDataOfSize(offset, sizeof(fat_arch))) {
106 if (is_fat64) {
107 fat_arch_64 arch;
108 arch.cputype = data.GetU32(&offset);
109 arch.cpusubtype = data.GetU32(&offset);
110 arch.offset = data.GetU64(&offset);
111 arch.size = data.GetU64(&offset);
112 arch.align = data.GetU32(&offset);
113 arch.reserved = data.GetU32(&offset);
114 fat_archs.emplace_back(arch);
115 } else {
116 fat_arch arch;
117 arch.cputype = data.GetU32(&offset);
118 arch.cpusubtype = data.GetU32(&offset);
119 arch.offset = data.GetU32(&offset);
120 arch.size = data.GetU32(&offset);
121 arch.align = data.GetU32(&offset);
122 fat_archs.emplace_back(arch);
123 }
124 }
125 }
126 return true;
127 }
128
129 memset(&header, 0, sizeof(header));
130 return true;
131 }
132
GetNumArchitectures() const133 size_t ObjectContainerUniversalMachO::GetNumArchitectures() const {
134 return m_header.nfat_arch;
135 }
136
GetArchitectureAtIndex(uint32_t idx,ArchSpec & arch) const137 bool ObjectContainerUniversalMachO::GetArchitectureAtIndex(
138 uint32_t idx, ArchSpec &arch) const {
139 if (idx < m_header.nfat_arch) {
140 arch.SetArchitecture(eArchTypeMachO, m_fat_archs[idx].GetCPUType(),
141 m_fat_archs[idx].GetCPUSubType());
142 return true;
143 }
144 return false;
145 }
146
147 ObjectFileSP
GetObjectFile(const FileSpec * file)148 ObjectContainerUniversalMachO::GetObjectFile(const FileSpec *file) {
149 uint32_t arch_idx = 0;
150 ArchSpec arch;
151 // If the module hasn't specified an architecture yet, set it to the default
152 // architecture:
153 ModuleSP module_sp(GetModule());
154 if (module_sp) {
155 if (!module_sp->GetArchitecture().IsValid()) {
156 arch = Target::GetDefaultArchitecture();
157 if (!arch.IsValid())
158 arch.SetTriple(LLDB_ARCH_DEFAULT);
159 } else
160 arch = module_sp->GetArchitecture();
161
162 ArchSpec curr_arch;
163 // First, try to find an exact match for the Arch of the Target.
164 for (arch_idx = 0; arch_idx < m_header.nfat_arch; ++arch_idx) {
165 if (GetArchitectureAtIndex(arch_idx, curr_arch) &&
166 arch.IsExactMatch(curr_arch))
167 break;
168 }
169
170 // Failing an exact match, try to find a compatible Arch of the Target.
171 if (arch_idx >= m_header.nfat_arch) {
172 for (arch_idx = 0; arch_idx < m_header.nfat_arch; ++arch_idx) {
173 if (GetArchitectureAtIndex(arch_idx, curr_arch) &&
174 arch.IsCompatibleMatch(curr_arch))
175 break;
176 }
177 }
178
179 if (arch_idx < m_header.nfat_arch) {
180 DataBufferSP data_sp;
181 lldb::offset_t data_offset = 0;
182 return ObjectFile::FindPlugin(
183 module_sp, file, m_offset + m_fat_archs[arch_idx].GetOffset(),
184 m_fat_archs[arch_idx].GetSize(), data_sp, data_offset);
185 }
186 }
187 return ObjectFileSP();
188 }
189
GetModuleSpecifications(const lldb_private::FileSpec & file,lldb::DataBufferSP & data_sp,lldb::offset_t data_offset,lldb::offset_t file_offset,lldb::offset_t file_size,lldb_private::ModuleSpecList & specs)190 size_t ObjectContainerUniversalMachO::GetModuleSpecifications(
191 const lldb_private::FileSpec &file, lldb::DataBufferSP &data_sp,
192 lldb::offset_t data_offset, lldb::offset_t file_offset,
193 lldb::offset_t file_size, lldb_private::ModuleSpecList &specs) {
194 const size_t initial_count = specs.GetSize();
195
196 DataExtractor data;
197 data.SetData(data_sp, data_offset, data_sp->GetByteSize());
198
199 if (ObjectContainerUniversalMachO::MagicBytesMatch(data)) {
200 llvm::MachO::fat_header header;
201 std::vector<FatArch> fat_archs;
202 if (ParseHeader(data, header, fat_archs)) {
203 for (const FatArch &fat_arch : fat_archs) {
204 const lldb::offset_t slice_file_offset =
205 fat_arch.GetOffset() + file_offset;
206 if (fat_arch.GetOffset() < file_size && file_size > slice_file_offset) {
207 ObjectFile::GetModuleSpecifications(
208 file, slice_file_offset, file_size - slice_file_offset, specs);
209 }
210 }
211 }
212 }
213 return specs.GetSize() - initial_count;
214 }
215