1//===-- BinaryHolder.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// This program is a utility that aims to be a dropin replacement for
10// Darwin's dsymutil.
11//
12//===----------------------------------------------------------------------===//
13
14#include "BinaryHolder.h"
15#include "llvm/Object/MachO.h"
16#include "llvm/Support/WithColor.h"
17#include "llvm/Support/raw_ostream.h"
18
19namespace llvm {
20namespace dsymutil {
21
22static std::pair<StringRef, StringRef>
23getArchiveAndObjectName(StringRef Filename) {
24 StringRef Archive = Filename.substr(Start: 0, N: Filename.rfind(C: '('));
25 StringRef Object = Filename.substr(Start: Archive.size() + 1).drop_back();
26 return {Archive, Object};
27}
28
29static bool isArchive(StringRef Filename) { return Filename.ends_with(Suffix: ")"); }
30
31static std::vector<MemoryBufferRef>
32getMachOFatMemoryBuffers(StringRef Filename, MemoryBuffer &Mem,
33 object::MachOUniversalBinary &Fat) {
34 std::vector<MemoryBufferRef> Buffers;
35 StringRef FatData = Fat.getData();
36 for (auto It = Fat.begin_objects(), End = Fat.end_objects(); It != End;
37 ++It) {
38 StringRef ObjData = FatData.substr(Start: It->getOffset(), N: It->getSize());
39 Buffers.emplace_back(args&: ObjData, args&: Filename);
40 }
41 return Buffers;
42}
43
44BinaryHolder::BinaryHolder(IntrusiveRefCntPtr<vfs::FileSystem> VFS,
45 BinaryHolder::Options Opts)
46 : VFS(VFS), Opts(Opts) {}
47
48Error BinaryHolder::ArchiveEntry::load(IntrusiveRefCntPtr<vfs::FileSystem> VFS,
49 StringRef Filename,
50 TimestampTy Timestamp, Options Opts) {
51 StringRef ArchiveFilename = getArchiveAndObjectName(Filename).first;
52
53 // Try to load archive and force it to be memory mapped.
54 auto ErrOrBuff = (ArchiveFilename == "-")
55 ? MemoryBuffer::getSTDIN()
56 : VFS->getBufferForFile(Name: ArchiveFilename, FileSize: -1, RequiresNullTerminator: false);
57 if (auto Err = ErrOrBuff.getError())
58 return errorCodeToError(EC: Err);
59
60 MemBuffer = std::move(*ErrOrBuff);
61
62 if (Opts.Verbose)
63 WithColor::note() << "loaded archive '" << ArchiveFilename << "'\n";
64
65 // Load one or more archive buffers, depending on whether we're dealing with
66 // a fat binary.
67 std::vector<MemoryBufferRef> ArchiveBuffers;
68
69 auto ErrOrFat =
70 object::MachOUniversalBinary::create(Source: MemBuffer->getMemBufferRef());
71 if (!ErrOrFat) {
72 consumeError(Err: ErrOrFat.takeError());
73 ArchiveBuffers.push_back(x: MemBuffer->getMemBufferRef());
74 } else {
75 FatBinary = std::move(*ErrOrFat);
76 FatBinaryName = std::string(ArchiveFilename);
77 ArchiveBuffers =
78 getMachOFatMemoryBuffers(Filename: FatBinaryName, Mem&: *MemBuffer, Fat&: *FatBinary);
79 }
80
81 // Finally, try to load the archives.
82 Archives.reserve(n: ArchiveBuffers.size());
83 for (auto MemRef : ArchiveBuffers) {
84 auto ErrOrArchive = object::Archive::create(Source: MemRef);
85 if (!ErrOrArchive)
86 return ErrOrArchive.takeError();
87 Archives.push_back(x: std::move(*ErrOrArchive));
88 }
89
90 return Error::success();
91}
92
93Error BinaryHolder::ObjectEntry::load(IntrusiveRefCntPtr<vfs::FileSystem> VFS,
94 StringRef Filename, TimestampTy Timestamp,
95 Options Opts) {
96 // Try to load regular binary and force it to be memory mapped.
97 auto ErrOrBuff = (Filename == "-")
98 ? MemoryBuffer::getSTDIN()
99 : VFS->getBufferForFile(Name: Filename, FileSize: -1, RequiresNullTerminator: false);
100 if (auto Err = ErrOrBuff.getError())
101 return errorCodeToError(EC: Err);
102
103 if (Opts.Warn && Filename != "-" && Timestamp != sys::TimePoint<>()) {
104 llvm::ErrorOr<vfs::Status> Stat = VFS->status(Path: Filename);
105 if (!Stat)
106 return errorCodeToError(EC: Stat.getError());
107 if (Timestamp != std::chrono::time_point_cast<std::chrono::seconds>(
108 t: Stat->getLastModificationTime()))
109 WithColor::warning() << Filename
110 << ": timestamp mismatch between object file ("
111 << Stat->getLastModificationTime()
112 << ") and debug map (" << Timestamp << ")\n";
113 }
114
115 MemBuffer = std::move(*ErrOrBuff);
116
117 if (Opts.Verbose)
118 WithColor::note() << "loaded object.\n";
119
120 // Load one or more object buffers, depending on whether we're dealing with a
121 // fat binary.
122 std::vector<MemoryBufferRef> ObjectBuffers;
123
124 auto ErrOrFat =
125 object::MachOUniversalBinary::create(Source: MemBuffer->getMemBufferRef());
126 if (!ErrOrFat) {
127 consumeError(Err: ErrOrFat.takeError());
128 ObjectBuffers.push_back(x: MemBuffer->getMemBufferRef());
129 } else {
130 FatBinary = std::move(*ErrOrFat);
131 FatBinaryName = std::string(Filename);
132 ObjectBuffers =
133 getMachOFatMemoryBuffers(Filename: FatBinaryName, Mem&: *MemBuffer, Fat&: *FatBinary);
134 }
135
136 Objects.reserve(n: ObjectBuffers.size());
137 for (auto MemRef : ObjectBuffers) {
138 auto ErrOrObjectFile = object::ObjectFile::createObjectFile(Object: MemRef);
139 if (!ErrOrObjectFile)
140 return ErrOrObjectFile.takeError();
141 Objects.push_back(x: std::move(*ErrOrObjectFile));
142 }
143
144 return Error::success();
145}
146
147std::vector<const object::ObjectFile *>
148BinaryHolder::ObjectEntry::getObjects() const {
149 std::vector<const object::ObjectFile *> Result;
150 Result.reserve(n: Objects.size());
151 for (auto &Object : Objects) {
152 Result.push_back(x: Object.get());
153 }
154 return Result;
155}
156Expected<const object::ObjectFile &>
157BinaryHolder::ObjectEntry::getObject(const Triple &T) const {
158 for (const auto &Obj : Objects) {
159 if (const auto *MachO = dyn_cast<object::MachOObjectFile>(Val: Obj.get())) {
160 if (MachO->getArchTriple().str() == T.str())
161 return *MachO;
162 } else if (Obj->getArch() == T.getArch())
163 return *Obj;
164 }
165 return errorCodeToError(EC: object::object_error::arch_not_found);
166}
167
168Expected<const BinaryHolder::ObjectEntry &>
169BinaryHolder::ArchiveEntry::getObjectEntry(StringRef Filename,
170 TimestampTy Timestamp,
171 Options Opts) {
172 StringRef ArchiveFilename;
173 StringRef ObjectFilename;
174 std::tie(args&: ArchiveFilename, args&: ObjectFilename) = getArchiveAndObjectName(Filename);
175 KeyTy Key = {ObjectFilename, Timestamp};
176
177 // Try the cache first.
178 std::lock_guard<std::mutex> Lock(MemberCacheMutex);
179 if (auto It = MemberCache.find(Val: Key); It != MemberCache.end())
180 return *It->second;
181
182 // Create a new ObjectEntry, but don't add it to the cache yet. Loading of
183 // the archive members might fail and we don't want to lock the whole archive
184 // during this operation.
185 auto OE = std::make_unique<ObjectEntry>();
186
187 for (const auto &Archive : Archives) {
188 Error Err = Error::success();
189 for (const auto &Child : Archive->children(Err)) {
190 if (auto NameOrErr = Child.getName()) {
191 if (*NameOrErr == ObjectFilename) {
192 auto ModTimeOrErr = Child.getLastModified();
193 if (!ModTimeOrErr)
194 return ModTimeOrErr.takeError();
195
196 if (Timestamp != sys::TimePoint<>() &&
197 Timestamp != std::chrono::time_point_cast<std::chrono::seconds>(
198 t: ModTimeOrErr.get())) {
199 if (Opts.Verbose)
200 WithColor::warning()
201 << *NameOrErr
202 << ": timestamp mismatch between archive member ("
203 << ModTimeOrErr.get() << ") and debug map (" << Timestamp
204 << ")\n";
205 continue;
206 }
207
208 if (Opts.Verbose)
209 WithColor::note() << "found member in archive.\n";
210
211 auto ErrOrMem = Child.getMemoryBufferRef();
212 if (!ErrOrMem)
213 return ErrOrMem.takeError();
214
215 auto ErrOrObjectFile =
216 object::ObjectFile::createObjectFile(Object: *ErrOrMem);
217 if (!ErrOrObjectFile)
218 return ErrOrObjectFile.takeError();
219
220 OE->Objects.push_back(x: std::move(*ErrOrObjectFile));
221 }
222 }
223 }
224 if (Err)
225 return std::move(Err);
226 }
227
228 if (OE->Objects.empty())
229 return errorCodeToError(EC: errc::no_such_file_or_directory);
230
231 return *(MemberCache[Key] = std::move(OE));
232}
233
234Expected<const BinaryHolder::ObjectEntry &>
235BinaryHolder::getObjectEntry(StringRef Filename, TimestampTy Timestamp) {
236 if (Opts.Verbose)
237 WithColor::note() << "trying to open '" << Filename << "'\n";
238
239 // If this is an archive, we might have either the object or the archive
240 // cached. In this case we can load it without accessing the file system.
241 if (isArchive(Filename)) {
242 StringRef ArchiveFilename = getArchiveAndObjectName(Filename).first;
243 std::lock_guard<std::mutex> Lock(ArchiveCacheMutex);
244 ArchiveRefCounter[ArchiveFilename]++;
245 if (auto It = ArchiveCache.find(Key: ArchiveFilename);
246 It != ArchiveCache.end()) {
247 return It->second->getObjectEntry(Filename, Timestamp, Opts);
248 } else {
249 auto AE = std::make_unique<ArchiveEntry>();
250 auto Err = AE->load(VFS, Filename, Timestamp, Opts);
251 if (Err) {
252 // Don't return the error here: maybe the file wasn't an archive.
253 llvm::consumeError(Err: std::move(Err));
254 } else {
255 auto &Cache = ArchiveCache[ArchiveFilename];
256 Cache = std::move(AE);
257 return Cache->getObjectEntry(Filename, Timestamp, Opts);
258 }
259 }
260 }
261
262 // If this is an object, we might have it cached. If not we'll have to load
263 // it from the file system and cache it now.
264 std::lock_guard<std::mutex> Lock(ObjectCacheMutex);
265 ObjectRefCounter[Filename]++;
266 if (!ObjectCache.count(Key: Filename)) {
267 auto OE = std::make_unique<ObjectEntry>();
268 auto Err = OE->load(VFS, Filename, Timestamp, Opts);
269 if (Err)
270 return std::move(Err);
271 ObjectCache[Filename] = std::move(OE);
272 }
273
274 return *ObjectCache[Filename];
275}
276
277void BinaryHolder::clear() {
278 std::lock_guard<std::mutex> ArchiveLock(ArchiveCacheMutex);
279 std::lock_guard<std::mutex> ObjectLock(ObjectCacheMutex);
280 ArchiveCache.clear();
281 ObjectCache.clear();
282}
283
284void BinaryHolder::eraseObjectEntry(StringRef Filename) {
285 if (Opts.Verbose)
286 WithColor::note() << "erasing '" << Filename << "' from cache\n";
287
288 if (isArchive(Filename)) {
289 StringRef ArchiveFilename = getArchiveAndObjectName(Filename).first;
290 std::lock_guard<std::mutex> Lock(ArchiveCacheMutex);
291 if (--ArchiveRefCounter[ArchiveFilename] == 0)
292 ArchiveCache.erase(Key: ArchiveFilename);
293 return;
294 }
295
296 std::lock_guard<std::mutex> Lock(ObjectCacheMutex);
297 if (--ObjectRefCounter[Filename] == 0)
298 ObjectCache.erase(Key: Filename);
299}
300
301} // namespace dsymutil
302} // namespace llvm
303