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 
12 #include "llvm/Support/FileSystem.h"
13 #include "llvm/Support/Threading.h"
14 #include "llvm/Support/raw_ostream.h"
15 
16 using namespace lldb_private;
17 using namespace lldb_private::repro;
18 using namespace llvm;
19 using namespace llvm::yaml;
20 
21 static llvm::Optional<bool> GetEnv(const char *var) {
22   std::string val = llvm::StringRef(getenv(var)).lower();
23   if (val == "0" || val == "off")
24     return false;
25   if (val == "1" || val == "on")
26     return true;
27   return {};
28 }
29 
30 Reproducer &Reproducer::Instance() { return *InstanceImpl(); }
31 
32 llvm::Error Reproducer::Initialize(ReproducerMode mode,
33                                    llvm::Optional<FileSpec> root) {
34   lldbassert(!InstanceImpl() && "Already initialized.");
35   InstanceImpl().emplace();
36 
37   // The environment can override the capture mode.
38   if (mode != ReproducerMode::Replay) {
39     if (llvm::Optional<bool> override = GetEnv("LLDB_CAPTURE_REPRODUCER")) {
40       if (*override)
41         mode = ReproducerMode::Capture;
42       else
43         mode = ReproducerMode::Off;
44     }
45   }
46 
47   switch (mode) {
48   case ReproducerMode::Capture: {
49     if (!root) {
50       SmallString<128> repro_dir;
51       auto ec = sys::fs::createUniqueDirectory("reproducer", repro_dir);
52       if (ec)
53         return make_error<StringError>(
54             "unable to create unique reproducer directory", ec);
55       root.emplace(repro_dir);
56     } else {
57       auto ec = sys::fs::create_directory(root->GetPath());
58       if (ec)
59         return make_error<StringError>("unable to create reproducer directory",
60                                        ec);
61     }
62     return Instance().SetCapture(root);
63   } break;
64   case ReproducerMode::Replay:
65     return Instance().SetReplay(root, /*passive*/ false);
66   case ReproducerMode::PassiveReplay:
67     return Instance().SetReplay(root, /*passive*/ true);
68   case ReproducerMode::Off:
69     break;
70   };
71 
72   return Error::success();
73 }
74 
75 bool Reproducer::Initialized() { return InstanceImpl().operator bool(); }
76 
77 void Reproducer::Terminate() {
78   lldbassert(InstanceImpl() && "Already terminated.");
79   InstanceImpl().reset();
80 }
81 
82 Optional<Reproducer> &Reproducer::InstanceImpl() {
83   static Optional<Reproducer> g_reproducer;
84   return g_reproducer;
85 }
86 
87 const Generator *Reproducer::GetGenerator() const {
88   std::lock_guard<std::mutex> guard(m_mutex);
89   if (m_generator)
90     return &(*m_generator);
91   return nullptr;
92 }
93 
94 const Loader *Reproducer::GetLoader() const {
95   std::lock_guard<std::mutex> guard(m_mutex);
96   if (m_loader)
97     return &(*m_loader);
98   return nullptr;
99 }
100 
101 Generator *Reproducer::GetGenerator() {
102   std::lock_guard<std::mutex> guard(m_mutex);
103   if (m_generator)
104     return &(*m_generator);
105   return nullptr;
106 }
107 
108 Loader *Reproducer::GetLoader() {
109   std::lock_guard<std::mutex> guard(m_mutex);
110   if (m_loader)
111     return &(*m_loader);
112   return nullptr;
113 }
114 
115 llvm::Error Reproducer::SetCapture(llvm::Optional<FileSpec> root) {
116   std::lock_guard<std::mutex> guard(m_mutex);
117 
118   if (root && m_loader)
119     return make_error<StringError>(
120         "cannot generate a reproducer when replay one",
121         inconvertibleErrorCode());
122 
123   if (!root) {
124     m_generator.reset();
125     return Error::success();
126   }
127 
128   m_generator.emplace(*root);
129   return Error::success();
130 }
131 
132 llvm::Error Reproducer::SetReplay(llvm::Optional<FileSpec> root, bool passive) {
133   std::lock_guard<std::mutex> guard(m_mutex);
134 
135   if (root && m_generator)
136     return make_error<StringError>(
137         "cannot replay a reproducer when generating one",
138         inconvertibleErrorCode());
139 
140   if (!root) {
141     m_loader.reset();
142     return Error::success();
143   }
144 
145   m_loader.emplace(*root, passive);
146   if (auto e = m_loader->LoadIndex())
147     return e;
148 
149   return Error::success();
150 }
151 
152 FileSpec Reproducer::GetReproducerPath() const {
153   if (auto g = GetGenerator())
154     return g->GetRoot();
155   if (auto l = GetLoader())
156     return l->GetRoot();
157   return {};
158 }
159 
160 static FileSpec MakeAbsolute(const FileSpec &file_spec) {
161   SmallString<128> path;
162   file_spec.GetPath(path, false);
163   llvm::sys::fs::make_absolute(path);
164   return FileSpec(path, file_spec.GetPathStyle());
165 }
166 
167 Generator::Generator(FileSpec root) : m_root(MakeAbsolute(std::move(root))) {
168   GetOrCreate<repro::WorkingDirectoryProvider>();
169   GetOrCreate<repro::HomeDirectoryProvider>();
170 }
171 
172 Generator::~Generator() {
173   if (!m_done) {
174     if (m_auto_generate)
175       Keep();
176     else
177       Discard();
178   }
179 }
180 
181 ProviderBase *Generator::Register(std::unique_ptr<ProviderBase> provider) {
182   std::lock_guard<std::mutex> lock(m_providers_mutex);
183   std::pair<const void *, std::unique_ptr<ProviderBase>> key_value(
184       provider->DynamicClassID(), std::move(provider));
185   auto e = m_providers.insert(std::move(key_value));
186   return e.first->getSecond().get();
187 }
188 
189 void Generator::Keep() {
190   assert(!m_done);
191   m_done = true;
192 
193   for (auto &provider : m_providers)
194     provider.second->Keep();
195 
196   AddProvidersToIndex();
197 }
198 
199 void Generator::Discard() {
200   assert(!m_done);
201   m_done = true;
202 
203   for (auto &provider : m_providers)
204     provider.second->Discard();
205 
206   llvm::sys::fs::remove_directories(m_root.GetPath());
207 }
208 
209 void Generator::SetAutoGenerate(bool b) { m_auto_generate = b; }
210 
211 bool Generator::IsAutoGenerate() const { return m_auto_generate; }
212 
213 const FileSpec &Generator::GetRoot() const { return m_root; }
214 
215 void Generator::AddProvidersToIndex() {
216   FileSpec index = m_root;
217   index.AppendPathComponent("index.yaml");
218 
219   std::error_code EC;
220   auto strm = std::make_unique<raw_fd_ostream>(index.GetPath(), EC,
221                                                sys::fs::OpenFlags::OF_None);
222   yaml::Output yout(*strm);
223 
224   std::vector<std::string> files;
225   files.reserve(m_providers.size());
226   for (auto &provider : m_providers) {
227     files.emplace_back(provider.second->GetFile());
228   }
229 
230   yout << files;
231 }
232 
233 Loader::Loader(FileSpec root, bool passive)
234     : m_root(MakeAbsolute(std::move(root))), m_loaded(false),
235       m_passive_replay(passive) {}
236 
237 llvm::Error Loader::LoadIndex() {
238   if (m_loaded)
239     return llvm::Error::success();
240 
241   FileSpec index = m_root.CopyByAppendingPathComponent("index.yaml");
242 
243   auto error_or_file = MemoryBuffer::getFile(index.GetPath());
244   if (auto err = error_or_file.getError())
245     return make_error<StringError>("unable to load reproducer index", err);
246 
247   yaml::Input yin((*error_or_file)->getBuffer());
248   yin >> m_files;
249   if (auto err = yin.error())
250     return make_error<StringError>("unable to read reproducer index", err);
251 
252   // Sort files to speed up search.
253   llvm::sort(m_files);
254 
255   // Remember that we've loaded the index.
256   m_loaded = true;
257 
258   return llvm::Error::success();
259 }
260 
261 bool Loader::HasFile(StringRef file) {
262   assert(m_loaded);
263   auto it = std::lower_bound(m_files.begin(), m_files.end(), file.str());
264   return (it != m_files.end()) && (*it == file);
265 }
266 
267 llvm::Expected<std::unique_ptr<DataRecorder>>
268 DataRecorder::Create(const FileSpec &filename) {
269   std::error_code ec;
270   auto recorder = std::make_unique<DataRecorder>(std::move(filename), ec);
271   if (ec)
272     return llvm::errorCodeToError(ec);
273   return std::move(recorder);
274 }
275 
276 llvm::Expected<std::unique_ptr<YamlRecorder>>
277 YamlRecorder::Create(const FileSpec &filename) {
278   std::error_code ec;
279   auto recorder = std::make_unique<YamlRecorder>(std::move(filename), ec);
280   if (ec)
281     return llvm::errorCodeToError(ec);
282   return std::move(recorder);
283 }
284 
285 void VersionProvider::Keep() {
286   FileSpec file = GetRoot().CopyByAppendingPathComponent(Info::file);
287   std::error_code ec;
288   llvm::raw_fd_ostream os(file.GetPath(), ec, llvm::sys::fs::OF_Text);
289   if (ec)
290     return;
291   os << m_version << "\n";
292 }
293 
294 void FileProvider::RecordInterestingDirectory(const llvm::Twine &dir) {
295   if (m_collector)
296     m_collector->addFile(dir);
297 }
298 
299 void FileProvider::RecordInterestingDirectoryRecursive(const llvm::Twine &dir) {
300   if (m_collector)
301     m_collector->addDirectory(dir);
302 }
303 
304 void ProviderBase::anchor() {}
305 char CommandProvider::ID = 0;
306 char FileProvider::ID = 0;
307 char ProviderBase::ID = 0;
308 char VersionProvider::ID = 0;
309 char WorkingDirectoryProvider::ID = 0;
310 char HomeDirectoryProvider::ID = 0;
311 const char *CommandProvider::Info::file = "command-interpreter.yaml";
312 const char *CommandProvider::Info::name = "command-interpreter";
313 const char *FileProvider::Info::file = "files.yaml";
314 const char *FileProvider::Info::name = "files";
315 const char *VersionProvider::Info::file = "version.txt";
316 const char *VersionProvider::Info::name = "version";
317 const char *WorkingDirectoryProvider::Info::file = "cwd.txt";
318 const char *WorkingDirectoryProvider::Info::name = "cwd";
319 const char *HomeDirectoryProvider::Info::file = "home.txt";
320 const char *HomeDirectoryProvider::Info::name = "home";
321