clang-tools  10.0.0git
QueryDriverDatabase.cpp
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1 //===--- QueryDriverDatabase.cpp ---------------------------------*- C++-*-===//
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 // Some compiler drivers have implicit search mechanism for system headers.
9 // This compilation database implementation tries to extract that information by
10 // executing the driver in verbose mode. gcc-compatible drivers print something
11 // like:
12 // ....
13 // ....
14 // #include <...> search starts here:
15 // /usr/lib/gcc/x86_64-linux-gnu/7/include
16 // /usr/local/include
17 // /usr/lib/gcc/x86_64-linux-gnu/7/include-fixed
18 // /usr/include/x86_64-linux-gnu
19 // /usr/include
20 // End of search list.
21 // ....
22 // ....
23 // This component parses that output and adds each path to command line args
24 // provided by Base, after prepending them with -isystem. Therefore current
25 // implementation would not work with a driver that is not gcc-compatible.
26 //
27 // First argument of the command line received from underlying compilation
28 // database is used as compiler driver path. Due to this arbitrary binary
29 // execution, this mechanism is not used by default and only executes binaries
30 // in the paths that are explicitly whitelisted by the user.
31 
33 #include "Logger.h"
34 #include "Path.h"
35 #include "Trace.h"
36 #include "clang/Driver/Types.h"
37 #include "clang/Tooling/CompilationDatabase.h"
38 #include "llvm/ADT/DenseMap.h"
39 #include "llvm/ADT/ScopeExit.h"
40 #include "llvm/ADT/SmallString.h"
41 #include "llvm/ADT/StringExtras.h"
42 #include "llvm/ADT/StringRef.h"
43 #include "llvm/ADT/iterator_range.h"
44 #include "llvm/Support/FileSystem.h"
45 #include "llvm/Support/MemoryBuffer.h"
46 #include "llvm/Support/Path.h"
47 #include "llvm/Support/Program.h"
48 #include "llvm/Support/Regex.h"
49 #include "llvm/Support/ScopedPrinter.h"
50 #include <algorithm>
51 #include <map>
52 #include <string>
53 #include <vector>
54 
55 namespace clang {
56 namespace clangd {
57 namespace {
58 
59 std::vector<std::string> parseDriverOutput(llvm::StringRef Output) {
60  std::vector<std::string> SystemIncludes;
61  const char SIS[] = "#include <...> search starts here:";
62  const char SIE[] = "End of search list.";
63  llvm::SmallVector<llvm::StringRef, 8> Lines;
64  Output.split(Lines, '\n', /*MaxSplit=*/-1, /*KeepEmpty=*/false);
65 
66  auto StartIt = llvm::find_if(
67  Lines, [SIS](llvm::StringRef Line) { return Line.trim() == SIS; });
68  if (StartIt == Lines.end()) {
69  elog("System include extraction: start marker not found: {0}", Output);
70  return {};
71  }
72  ++StartIt;
73  const auto EndIt =
74  llvm::find_if(llvm::make_range(StartIt, Lines.end()),
75  [SIE](llvm::StringRef Line) { return Line.trim() == SIE; });
76  if (EndIt == Lines.end()) {
77  elog("System include extraction: end marker missing: {0}", Output);
78  return {};
79  }
80 
81  for (llvm::StringRef Line : llvm::make_range(StartIt, EndIt)) {
82  SystemIncludes.push_back(Line.trim().str());
83  vlog("System include extraction: adding {0}", Line);
84  }
85  return SystemIncludes;
86 }
87 
88 std::vector<std::string> extractSystemIncludes(PathRef Driver,
89  llvm::StringRef Lang,
90  llvm::Regex &QueryDriverRegex) {
91  trace::Span Tracer("Extract system includes");
92  SPAN_ATTACH(Tracer, "driver", Driver);
93  SPAN_ATTACH(Tracer, "lang", Lang);
94 
95  if (!QueryDriverRegex.match(Driver)) {
96  vlog("System include extraction: not whitelisted driver {0}", Driver);
97  return {};
98  }
99 
100  if (!llvm::sys::fs::exists(Driver)) {
101  elog("System include extraction: {0} does not exist.", Driver);
102  return {};
103  }
104  if (!llvm::sys::fs::can_execute(Driver)) {
105  elog("System include extraction: {0} is not executable.", Driver);
106  return {};
107  }
108 
109  llvm::SmallString<128> StdErrPath;
110  if (auto EC = llvm::sys::fs::createTemporaryFile("system-includes", "clangd",
111  StdErrPath)) {
112  elog("System include extraction: failed to create temporary file with "
113  "error {0}",
114  EC.message());
115  return {};
116  }
117  auto CleanUp = llvm::make_scope_exit(
118  [&StdErrPath]() { llvm::sys::fs::remove(StdErrPath); });
119 
120  llvm::Optional<llvm::StringRef> Redirects[] = {
121  {""}, {""}, llvm::StringRef(StdErrPath)};
122 
123  // Should we also preserve flags like "-sysroot", "-nostdinc" ?
124  const llvm::StringRef Args[] = {Driver, "-E", "-x", Lang, "-", "-v"};
125 
126  if (int RC = llvm::sys::ExecuteAndWait(Driver, Args, /*Env=*/llvm::None,
127  Redirects)) {
128  elog("System include extraction: driver execution failed with return code: "
129  "{0}",
130  llvm::to_string(RC));
131  return {};
132  }
133 
134  auto BufOrError = llvm::MemoryBuffer::getFile(StdErrPath);
135  if (!BufOrError) {
136  elog("System include extraction: failed to read {0} with error {1}",
137  StdErrPath, BufOrError.getError().message());
138  return {};
139  }
140 
141  auto Includes = parseDriverOutput(BufOrError->get()->getBuffer());
142  log("System include extractor: succesfully executed {0}, got includes: "
143  "\"{1}\"",
144  Driver, llvm::join(Includes, ", "));
145  return Includes;
146 }
147 
148 tooling::CompileCommand &
149 addSystemIncludes(tooling::CompileCommand &Cmd,
150  llvm::ArrayRef<std::string> SystemIncludes) {
151  for (llvm::StringRef Include : SystemIncludes) {
152  // FIXME(kadircet): This doesn't work when we have "--driver-mode=cl"
153  Cmd.CommandLine.push_back("-isystem");
154  Cmd.CommandLine.push_back(Include.str());
155  }
156  return Cmd;
157 }
158 
159 /// Converts a glob containing only ** or * into a regex.
160 std::string convertGlobToRegex(llvm::StringRef Glob) {
161  std::string RegText;
162  llvm::raw_string_ostream RegStream(RegText);
163  RegStream << '^';
164  for (size_t I = 0, E = Glob.size(); I < E; ++I) {
165  if (Glob[I] == '*') {
166  if (I + 1 < E && Glob[I + 1] == '*') {
167  // Double star, accept any sequence.
168  RegStream << ".*";
169  // Also skip the second star.
170  ++I;
171  } else {
172  // Single star, accept any sequence without a slash.
173  RegStream << "[^/]*";
174  }
175  } else {
176  RegStream << llvm::Regex::escape(Glob.substr(I, 1));
177  }
178  }
179  RegStream << '$';
180  RegStream.flush();
181  return RegText;
182 }
183 
184 /// Converts a glob containing only ** or * into a regex.
185 llvm::Regex convertGlobsToRegex(llvm::ArrayRef<std::string> Globs) {
186  assert(!Globs.empty() && "Globs cannot be empty!");
187  std::vector<std::string> RegTexts;
188  RegTexts.reserve(Globs.size());
189  for (llvm::StringRef Glob : Globs)
190  RegTexts.push_back(convertGlobToRegex(Glob));
191 
192  llvm::Regex Reg(llvm::join(RegTexts, "|"));
193  assert(Reg.isValid(RegTexts.front()) &&
194  "Created an invalid regex from globs");
195  return Reg;
196 }
197 
198 /// Extracts system includes from a trusted driver by parsing the output of
199 /// include search path and appends them to the commands coming from underlying
200 /// compilation database.
201 class QueryDriverDatabase : public GlobalCompilationDatabase {
202 public:
203  QueryDriverDatabase(llvm::ArrayRef<std::string> QueryDriverGlobs,
204  std::unique_ptr<GlobalCompilationDatabase> Base)
205  : QueryDriverRegex(convertGlobsToRegex(QueryDriverGlobs)),
206  Base(std::move(Base)) {
207  assert(this->Base);
208  BaseChanged =
209  this->Base->watch([this](const std::vector<std::string> &Changes) {
210  OnCommandChanged.broadcast(Changes);
211  });
212  }
213 
214  llvm::Optional<tooling::CompileCommand>
215  getCompileCommand(PathRef File) const override {
216  auto Cmd = Base->getCompileCommand(File);
217  if (!Cmd || Cmd->CommandLine.empty())
218  return Cmd;
219 
220  llvm::StringRef Lang;
221  for (size_t I = 0, E = Cmd->CommandLine.size(); I < E; ++I) {
222  llvm::StringRef Arg = Cmd->CommandLine[I];
223  if (Arg == "-x" && I + 1 < E)
224  Lang = Cmd->CommandLine[I + 1];
225  else if (Arg.startswith("-x"))
226  Lang = Arg.drop_front(2).trim();
227  }
228  if (Lang.empty()) {
229  llvm::StringRef Ext = llvm::sys::path::extension(File).trim('.');
230  auto Type = driver::types::lookupTypeForExtension(Ext);
231  if (Type == driver::types::TY_INVALID) {
232  elog("System include extraction: invalid file type for {0}", Ext);
233  return {};
234  }
235  Lang = driver::types::getTypeName(Type);
236  }
237 
238  llvm::SmallString<128> Driver(Cmd->CommandLine.front());
239  llvm::sys::fs::make_absolute(Cmd->Directory, Driver);
240  auto Key = std::make_pair(Driver.str(), Lang);
241 
242  std::vector<std::string> SystemIncludes;
243  {
244  std::lock_guard<std::mutex> Lock(Mu);
245 
246  auto It = DriverToIncludesCache.find(Key);
247  if (It != DriverToIncludesCache.end())
248  SystemIncludes = It->second;
249  else
250  DriverToIncludesCache[Key] = SystemIncludes =
251  extractSystemIncludes(Key.first, Key.second, QueryDriverRegex);
252  }
253 
254  return addSystemIncludes(*Cmd, SystemIncludes);
255  }
256 
257  llvm::Optional<ProjectInfo> getProjectInfo(PathRef File) const override {
258  return Base->getProjectInfo(File);
259  }
260 
261 private:
262  mutable std::mutex Mu;
263  // Caches includes extracted from a driver.
264  mutable std::map<std::pair<std::string, std::string>,
265  std::vector<std::string>>
266  DriverToIncludesCache;
267  mutable llvm::Regex QueryDriverRegex;
268 
269  std::unique_ptr<GlobalCompilationDatabase> Base;
270  CommandChanged::Subscription BaseChanged;
271 };
272 } // namespace
273 
274 std::unique_ptr<GlobalCompilationDatabase>
275 getQueryDriverDatabase(llvm::ArrayRef<std::string> QueryDriverGlobs,
276  std::unique_ptr<GlobalCompilationDatabase> Base) {
277  assert(Base && "Null base to SystemIncludeExtractor");
278  if (QueryDriverGlobs.empty())
279  return Base;
280  return std::make_unique<QueryDriverDatabase>(QueryDriverGlobs,
281  std::move(Base));
282 }
283 
284 } // namespace clangd
285 } // namespace clang
std::unique_ptr< GlobalCompilationDatabase > getQueryDriverDatabase(llvm::ArrayRef< std::string > QueryDriverGlobs, std::unique_ptr< GlobalCompilationDatabase > Base)
Extracts system include search path from drivers matching QueryDriverGlobs and adds them to the compi...
tooling::Replacements Changes
Definition: Format.cpp:108
llvm::StringRef PathRef
A typedef to represent a ref to file path.
Definition: Path.h:23
def make_absolute(f, directory)
Documents should not be synced at all.
void vlog(const char *Fmt, Ts &&... Vals)
Definition: Logger.h:67
void elog(const char *Fmt, Ts &&... Vals)
Definition: Logger.h:56
void log(const char *Fmt, Ts &&... Vals)
Definition: Logger.h:62
===– Representation.cpp - ClangDoc Representation --------—*- C++ -*-===//
const Expr * E
static std::string join(ArrayRef< SpecialMemberFunctionsCheck::SpecialMemberFunctionKind > SMFS, llvm::StringRef AndOr)
std::unique_ptr< GlobalCompilationDatabase > Base
#define SPAN_ATTACH(S, Name, Expr)
Attach a key-value pair to a Span event.
Definition: Trace.h:97
NodeType Type
unsigned Lines