1 //===-- Reproducer.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 "lldb/Utility/Reproducer.h"
10 #include "lldb/Utility/LLDBAssert.h"
11 #include "lldb/Utility/ReproducerProvider.h"
12 #include "lldb/Utility/Timer.h"
13 
14 #include "llvm/Support/FileSystem.h"
15 #include "llvm/Support/Threading.h"
16 #include "llvm/Support/raw_ostream.h"
17 
18 using namespace lldb_private;
19 using namespace lldb_private::repro;
20 using namespace llvm;
21 using namespace llvm::yaml;
22 
23 Reproducer &Reproducer::Instance() { return *InstanceImpl(); }
24 
25 llvm::Error Reproducer::Initialize(ReproducerMode mode,
26                                    llvm::Optional<FileSpec> root) {
27   lldbassert(!InstanceImpl() && "Already initialized.");
28   InstanceImpl().emplace();
29 
30   switch (mode) {
31   case ReproducerMode::Capture: {
32     if (!root) {
33       SmallString<128> repro_dir;
34       auto ec = sys::fs::createUniqueDirectory("reproducer", repro_dir);
35       if (ec)
36         return make_error<StringError>(
37             "unable to create unique reproducer directory", ec);
38       root.emplace(repro_dir);
39     } else {
40       auto ec = sys::fs::create_directory(root->GetPath());
41       if (ec)
42         return make_error<StringError>("unable to create reproducer directory",
43                                        ec);
44     }
45     return Instance().SetCapture(root);
46   } break;
47   case ReproducerMode::Off:
48     break;
49   };
50 
51   return Error::success();
52 }
53 
54 void Reproducer::Initialize() {
55   llvm::cantFail(Initialize(repro::ReproducerMode::Off, llvm::None));
56 }
57 
58 bool Reproducer::Initialized() { return InstanceImpl().operator bool(); }
59 
60 void Reproducer::Terminate() {
61   lldbassert(InstanceImpl() && "Already terminated.");
62   InstanceImpl().reset();
63 }
64 
65 Optional<Reproducer> &Reproducer::InstanceImpl() {
66   static Optional<Reproducer> g_reproducer;
67   return g_reproducer;
68 }
69 
70 const Generator *Reproducer::GetGenerator() const {
71   std::lock_guard<std::mutex> guard(m_mutex);
72   if (m_generator)
73     return &(*m_generator);
74   return nullptr;
75 }
76 
77 const Loader *Reproducer::GetLoader() const {
78   std::lock_guard<std::mutex> guard(m_mutex);
79   if (m_loader)
80     return &(*m_loader);
81   return nullptr;
82 }
83 
84 Generator *Reproducer::GetGenerator() {
85   std::lock_guard<std::mutex> guard(m_mutex);
86   if (m_generator)
87     return &(*m_generator);
88   return nullptr;
89 }
90 
91 Loader *Reproducer::GetLoader() {
92   std::lock_guard<std::mutex> guard(m_mutex);
93   if (m_loader)
94     return &(*m_loader);
95   return nullptr;
96 }
97 
98 llvm::Error Reproducer::SetCapture(llvm::Optional<FileSpec> root) {
99   std::lock_guard<std::mutex> guard(m_mutex);
100 
101   if (root && m_loader)
102     return make_error<StringError>(
103         "cannot generate a reproducer when replay one",
104         inconvertibleErrorCode());
105 
106   if (!root) {
107     m_generator.reset();
108     return Error::success();
109   }
110 
111   m_generator.emplace(*root);
112   return Error::success();
113 }
114 
115 FileSpec Reproducer::GetReproducerPath() const {
116   if (auto g = GetGenerator())
117     return g->GetRoot();
118   if (auto l = GetLoader())
119     return l->GetRoot();
120   return {};
121 }
122 
123 static FileSpec MakeAbsolute(const FileSpec &file_spec) {
124   SmallString<128> path;
125   file_spec.GetPath(path, false);
126   llvm::sys::fs::make_absolute(path);
127   return FileSpec(path, file_spec.GetPathStyle());
128 }
129 
130 Generator::Generator(FileSpec root) : m_root(MakeAbsolute(std::move(root))) {
131   GetOrCreate<repro::WorkingDirectoryProvider>();
132   GetOrCreate<repro::HomeDirectoryProvider>();
133 }
134 
135 Generator::~Generator() {
136   if (!m_done) {
137     if (m_auto_generate) {
138       Keep();
139       llvm::cantFail(Finalize(GetRoot()));
140     } else {
141       Discard();
142     }
143   }
144 }
145 
146 ProviderBase *Generator::Register(std::unique_ptr<ProviderBase> provider) {
147   std::lock_guard<std::mutex> lock(m_providers_mutex);
148   std::pair<const void *, std::unique_ptr<ProviderBase>> key_value(
149       provider->DynamicClassID(), std::move(provider));
150   auto e = m_providers.insert(std::move(key_value));
151   return e.first->getSecond().get();
152 }
153 
154 void Generator::Keep() {
155   LLDB_SCOPED_TIMER();
156   assert(!m_done);
157   m_done = true;
158 
159   for (auto &provider : m_providers)
160     provider.second->Keep();
161 
162   AddProvidersToIndex();
163 }
164 
165 void Generator::Discard() {
166   LLDB_SCOPED_TIMER();
167   assert(!m_done);
168   m_done = true;
169 
170   for (auto &provider : m_providers)
171     provider.second->Discard();
172 
173   llvm::sys::fs::remove_directories(m_root.GetPath());
174 }
175 
176 void Generator::SetAutoGenerate(bool b) { m_auto_generate = b; }
177 
178 bool Generator::IsAutoGenerate() const { return m_auto_generate; }
179 
180 const FileSpec &Generator::GetRoot() const { return m_root; }
181 
182 void Generator::AddProvidersToIndex() {
183   FileSpec index = m_root;
184   index.AppendPathComponent("index.yaml");
185 
186   std::error_code EC;
187   auto strm = std::make_unique<raw_fd_ostream>(index.GetPath(), EC,
188                                                sys::fs::OpenFlags::OF_None);
189   yaml::Output yout(*strm);
190 
191   std::vector<std::string> files;
192   files.reserve(m_providers.size());
193   for (auto &provider : m_providers) {
194     files.emplace_back(provider.second->GetFile());
195   }
196 
197   yout << files;
198 }
199 
200 Loader::Loader(FileSpec root, bool passive)
201     : m_root(MakeAbsolute(std::move(root))), m_loaded(false) {}
202 
203 llvm::Error Loader::LoadIndex() {
204   if (m_loaded)
205     return llvm::Error::success();
206 
207   FileSpec index = m_root.CopyByAppendingPathComponent("index.yaml");
208 
209   auto error_or_file = MemoryBuffer::getFile(index.GetPath());
210   if (auto err = error_or_file.getError())
211     return make_error<StringError>("unable to load reproducer index", err);
212 
213   yaml::Input yin((*error_or_file)->getBuffer());
214   yin >> m_files;
215   if (auto err = yin.error())
216     return make_error<StringError>("unable to read reproducer index", err);
217 
218   // Sort files to speed up search.
219   llvm::sort(m_files);
220 
221   // Remember that we've loaded the index.
222   m_loaded = true;
223 
224   return llvm::Error::success();
225 }
226 
227 bool Loader::HasFile(StringRef file) {
228   assert(m_loaded);
229   auto it = std::lower_bound(m_files.begin(), m_files.end(), file.str());
230   return (it != m_files.end()) && (*it == file);
231 }
232 
233 static llvm::Error addPaths(StringRef path,
234                             function_ref<void(StringRef)> callback) {
235   auto buffer = llvm::MemoryBuffer::getFile(path);
236   if (!buffer)
237     return errorCodeToError(buffer.getError());
238 
239   SmallVector<StringRef, 0> paths;
240   (*buffer)->getBuffer().split(paths, '\0');
241   for (StringRef p : paths) {
242     if (!p.empty() && llvm::sys::fs::exists(p))
243       callback(p);
244   }
245 
246   return errorCodeToError(llvm::sys::fs::remove(path));
247 }
248 
249 llvm::Error repro::Finalize(Loader *loader) {
250   if (!loader)
251     return make_error<StringError>("invalid loader",
252                                    llvm::inconvertibleErrorCode());
253 
254   FileSpec reproducer_root = loader->GetRoot();
255   std::string files_path =
256       reproducer_root.CopyByAppendingPathComponent("files.txt").GetPath();
257   std::string dirs_path =
258       reproducer_root.CopyByAppendingPathComponent("dirs.txt").GetPath();
259 
260   FileCollector collector(
261       reproducer_root.CopyByAppendingPathComponent("root").GetPath(),
262       reproducer_root.GetPath());
263 
264   if (Error e =
265           addPaths(files_path, [&](StringRef p) { collector.addFile(p); }))
266     return e;
267 
268   if (Error e =
269           addPaths(dirs_path, [&](StringRef p) { collector.addDirectory(p); }))
270     return e;
271 
272   FileSpec mapping =
273       reproducer_root.CopyByAppendingPathComponent(FileProvider::Info::file);
274   if (auto ec = collector.copyFiles(/*StopOnError=*/false))
275     return errorCodeToError(ec);
276   collector.writeMapping(mapping.GetPath());
277 
278   return llvm::Error::success();
279 }
280 
281 llvm::Error repro::Finalize(const FileSpec &root) {
282   Loader loader(root);
283   if (Error e = loader.LoadIndex())
284     return e;
285   return Finalize(&loader);
286 }
287