clang-tools  8.0.0
ModuleAssistant.cpp
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1 //===--- ModuleAssistant.cpp - Module map generation manager --*- C++ -*---===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file defines the module generation entry point function,
11 // createModuleMap, a Module class for representing a module,
12 // and various implementation functions for doing the underlying
13 // work, described below.
14 //
15 // The "Module" class represents a module, with members for storing the module
16 // name, associated header file names, and sub-modules, and an "output"
17 // function that recursively writes the module definitions.
18 //
19 // The "createModuleMap" function implements the top-level logic of the
20 // assistant mode. It calls a loadModuleDescriptions function to walk
21 // the header list passed to it and creates a tree of Module objects
22 // representing the module hierarchy, represented by a "Module" object,
23 // the "RootModule". This root module may or may not represent an actual
24 // module in the module map, depending on the "--root-module" option passed
25 // to modularize. It then calls a writeModuleMap function to set up the
26 // module map file output and walk the module tree, outputting the module
27 // map file using a stream obtained and managed by an
28 // llvm::ToolOutputFile object.
29 //
30 //===----------------------------------------------------------------------===//
31 
32 #include "Modularize.h"
33 #include "llvm/ADT/SmallString.h"
34 #include "llvm/Support/FileSystem.h"
35 #include "llvm/Support/Path.h"
36 #include "llvm/Support/ToolOutputFile.h"
37 #include <vector>
38 
39 // Local definitions:
40 
41 namespace {
42 
43 // Internal class definitions:
44 
45 // Represents a module.
46 class Module {
47 public:
48  Module(llvm::StringRef Name, bool Problem);
49  ~Module();
50  bool output(llvm::raw_fd_ostream &OS, int Indent);
51  Module *findSubModule(llvm::StringRef SubName);
52 
53 public:
54  std::string Name;
55  std::vector<std::string> HeaderFileNames;
56  std::vector<Module *> SubModules;
57  bool IsProblem;
58 };
59 
60 } // end anonymous namespace.
61 
62 // Module functions:
63 
64 // Constructors.
65 Module::Module(llvm::StringRef Name, bool Problem)
66  : Name(Name), IsProblem(Problem) {}
67 
68 // Destructor.
69 Module::~Module() {
70  // Free submodules.
71  while (!SubModules.empty()) {
72  Module *last = SubModules.back();
73  SubModules.pop_back();
74  delete last;
75  }
76 }
77 
78 // Write a module hierarchy to the given output stream.
79 bool Module::output(llvm::raw_fd_ostream &OS, int Indent) {
80  // If this is not the nameless root module, start a module definition.
81  if (Name.size() != 0) {
82  OS.indent(Indent);
83  OS << "module " << Name << " {\n";
84  Indent += 2;
85  }
86 
87  // Output submodules.
88  for (auto I = SubModules.begin(), E = SubModules.end(); I != E; ++I) {
89  if (!(*I)->output(OS, Indent))
90  return false;
91  }
92 
93  // Output header files.
94  for (auto I = HeaderFileNames.begin(), E = HeaderFileNames.end(); I != E;
95  ++I) {
96  OS.indent(Indent);
97  if (IsProblem || strstr((*I).c_str(), ".inl"))
98  OS << "exclude header \"" << *I << "\"\n";
99  else
100  OS << "header \"" << *I << "\"\n";
101  }
102 
103  // If this module has header files, output export directive.
104  if (HeaderFileNames.size() != 0) {
105  OS.indent(Indent);
106  OS << "export *\n";
107  }
108 
109  // If this is not the nameless root module, close the module definition.
110  if (Name.size() != 0) {
111  Indent -= 2;
112  OS.indent(Indent);
113  OS << "}\n";
114  }
115 
116  return true;
117 }
118 
119 // Lookup a sub-module.
120 Module *Module::findSubModule(llvm::StringRef SubName) {
121  for (auto I = SubModules.begin(), E = SubModules.end(); I != E; ++I) {
122  if ((*I)->Name == SubName)
123  return *I;
124  }
125  return nullptr;
126 }
127 
128 // Implementation functions:
129 
130 // Reserved keywords in module.modulemap syntax.
131 // Keep in sync with keywords in module map parser in Lex/ModuleMap.cpp,
132 // such as in ModuleMapParser::consumeToken().
133 static const char *const ReservedNames[] = {
134  "config_macros", "export", "module", "conflict", "framework",
135  "requires", "exclude", "header", "private", "explicit",
136  "link", "umbrella", "extern", "use", nullptr // Flag end.
137 };
138 
139 // Convert module name to a non-keyword.
140 // Prepends a '_' to the name if and only if the name is a keyword.
141 static std::string
142 ensureNoCollisionWithReservedName(llvm::StringRef MightBeReservedName) {
143  std::string SafeName = MightBeReservedName;
144  for (int Index = 0; ReservedNames[Index] != nullptr; ++Index) {
145  if (MightBeReservedName == ReservedNames[Index]) {
146  SafeName.insert(0, "_");
147  break;
148  }
149  }
150  return SafeName;
151 }
152 
153 // Convert module name to a non-keyword.
154 // Prepends a '_' to the name if and only if the name is a keyword.
155 static std::string
156 ensureVaidModuleName(llvm::StringRef MightBeInvalidName) {
157  std::string SafeName = MightBeInvalidName;
158  std::replace(SafeName.begin(), SafeName.end(), '-', '_');
159  std::replace(SafeName.begin(), SafeName.end(), '.', '_');
160  if (isdigit(SafeName[0]))
161  SafeName = "_" + SafeName;
162  return SafeName;
163 }
164 
165 // Add one module, given a header file path.
166 static bool addModuleDescription(Module *RootModule,
167  llvm::StringRef HeaderFilePath,
168  llvm::StringRef HeaderPrefix,
170  bool IsProblemFile) {
171  Module *CurrentModule = RootModule;
172  DependentsVector &FileDependents = Dependencies[HeaderFilePath];
173  std::string FilePath;
174  // Strip prefix.
175  // HeaderFilePath should be compared to natively-canonicalized Prefix.
176  llvm::SmallString<256> NativePath, NativePrefix;
177  llvm::sys::path::native(HeaderFilePath, NativePath);
178  llvm::sys::path::native(HeaderPrefix, NativePrefix);
179  if (NativePath.startswith(NativePrefix))
180  FilePath = NativePath.substr(NativePrefix.size() + 1);
181  else
182  FilePath = HeaderFilePath;
183  int Count = FileDependents.size();
184  // Headers that go into modules must not depend on other files being
185  // included first. If there are any dependents, warn user and omit.
186  if (Count != 0) {
187  llvm::errs() << "warning: " << FilePath
188  << " depends on other headers being included first,"
189  " meaning the module.modulemap won't compile."
190  " This header will be omitted from the module map.\n";
191  return true;
192  }
193  // Make canonical.
194  std::replace(FilePath.begin(), FilePath.end(), '\\', '/');
195  // Insert module into tree, using subdirectories as submodules.
196  for (llvm::sys::path::const_iterator I = llvm::sys::path::begin(FilePath),
197  E = llvm::sys::path::end(FilePath);
198  I != E; ++I) {
199  if ((*I)[0] == '.')
200  continue;
201  std::string Stem = llvm::sys::path::stem(*I);
203  Stem = ensureVaidModuleName(Stem);
204  Module *SubModule = CurrentModule->findSubModule(Stem);
205  if (!SubModule) {
206  SubModule = new Module(Stem, IsProblemFile);
207  CurrentModule->SubModules.push_back(SubModule);
208  }
209  CurrentModule = SubModule;
210  }
211  // Add header file name to headers.
212  CurrentModule->HeaderFileNames.push_back(FilePath);
213  return true;
214 }
215 
216 // Create the internal module tree representation.
217 static Module *loadModuleDescriptions(
218  llvm::StringRef RootModuleName, llvm::ArrayRef<std::string> HeaderFileNames,
219  llvm::ArrayRef<std::string> ProblemFileNames,
220  DependencyMap &Dependencies, llvm::StringRef HeaderPrefix) {
221 
222  // Create root module.
223  auto *RootModule = new Module(RootModuleName, false);
224 
225  llvm::SmallString<256> CurrentDirectory;
226  llvm::sys::fs::current_path(CurrentDirectory);
227 
228  // If no header prefix, use current directory.
229  if (HeaderPrefix.size() == 0)
230  HeaderPrefix = CurrentDirectory;
231 
232  // Walk the header file names and output the module map.
233  for (llvm::ArrayRef<std::string>::iterator I = HeaderFileNames.begin(),
234  E = HeaderFileNames.end();
235  I != E; ++I) {
236  std::string Header(*I);
237  bool IsProblemFile = false;
238  for (auto &ProblemFile : ProblemFileNames) {
239  if (ProblemFile == Header) {
240  IsProblemFile = true;
241  break;
242  }
243  }
244  // Add as a module.
245  if (!addModuleDescription(RootModule, Header, HeaderPrefix, Dependencies, IsProblemFile))
246  return nullptr;
247  }
248 
249  return RootModule;
250 }
251 
252 // Kick off the writing of the module map.
253 static bool writeModuleMap(llvm::StringRef ModuleMapPath,
254  llvm::StringRef HeaderPrefix, Module *RootModule) {
255  llvm::SmallString<256> HeaderDirectory(ModuleMapPath);
256  llvm::sys::path::remove_filename(HeaderDirectory);
257  llvm::SmallString<256> FilePath;
258 
259  // Get the module map file path to be used.
260  if ((HeaderDirectory.size() == 0) && (HeaderPrefix.size() != 0)) {
261  FilePath = HeaderPrefix;
262  // Prepend header file name prefix if it's not absolute.
263  llvm::sys::path::append(FilePath, ModuleMapPath);
264  llvm::sys::path::native(FilePath);
265  } else {
266  FilePath = ModuleMapPath;
267  llvm::sys::path::native(FilePath);
268  }
269 
270  // Set up module map output file.
271  std::error_code EC;
272  llvm::ToolOutputFile Out(FilePath, EC, llvm::sys::fs::F_Text);
273  if (EC) {
274  llvm::errs() << Argv0 << ": error opening " << FilePath << ":"
275  << EC.message() << "\n";
276  return false;
277  }
278 
279  // Get output stream from tool output buffer/manager.
280  llvm::raw_fd_ostream &OS = Out.os();
281 
282  // Output file comment.
283  OS << "// " << ModuleMapPath << "\n";
284  OS << "// Generated by: " << CommandLine << "\n\n";
285 
286  // Write module hierarchy from internal representation.
287  if (!RootModule->output(OS, 0))
288  return false;
289 
290  // Tell ToolOutputFile that we want to keep the file.
291  Out.keep();
292 
293  return true;
294 }
295 
296 // Global functions:
297 
298 // Module map generation entry point.
299 bool createModuleMap(llvm::StringRef ModuleMapPath,
300  llvm::ArrayRef<std::string> HeaderFileNames,
301  llvm::ArrayRef<std::string> ProblemFileNames,
302  DependencyMap &Dependencies, llvm::StringRef HeaderPrefix,
303  llvm::StringRef RootModuleName) {
304  // Load internal representation of modules.
305  std::unique_ptr<Module> RootModule(
307  RootModuleName, HeaderFileNames, ProblemFileNames, Dependencies,
308  HeaderPrefix));
309  if (!RootModule.get())
310  return false;
311 
312  // Write module map file.
313  return writeModuleMap(ModuleMapPath, HeaderPrefix, RootModule.get());
314 }
DependencyMap Dependencies
Map of top-level header file dependencies.
Common definitions for Modularize.
static bool addModuleDescription(Module *RootModule, llvm::StringRef HeaderFilePath, llvm::StringRef HeaderPrefix, DependencyMap &Dependencies, bool IsProblemFile)
llvm::SmallVector< std::string, 4 > DependentsVector
Definition: Modularize.h:32
const char * Argv0
Definition: Modularize.cpp:334
static const char *const ReservedNames[]
static bool writeModuleMap(llvm::StringRef ModuleMapPath, llvm::StringRef HeaderPrefix, Module *RootModule)
static Module * loadModuleDescriptions(llvm::StringRef RootModuleName, llvm::ArrayRef< std::string > HeaderFileNames, llvm::ArrayRef< std::string > ProblemFileNames, DependencyMap &Dependencies, llvm::StringRef HeaderPrefix)
static cl::opt< std::string > ModuleMapPath("module-map-path", cl::init(""), cl::desc("Turn on module map output and specify output path or file name." " If no path is specified and if prefix option is specified," " use prefix for file path."))
static std::string ensureVaidModuleName(llvm::StringRef MightBeInvalidName)
static constexpr llvm::StringLiteral Name
std::string CommandLine
Definition: Modularize.cpp:336
llvm::SmallVector< std::string, 32 > ProblemFileNames
List of header files with problems.
llvm::StringMap< DependentsVector > DependencyMap
Definition: Modularize.h:33
llvm::SmallVector< std::string, 32 > HeaderFileNames
List of top-level header files.
llvm::StringRef HeaderPrefix
The header prefix.
bool createModuleMap(llvm::StringRef ModuleMapPath, llvm::ArrayRef< std::string > HeaderFileNames, llvm::ArrayRef< std::string > ProblemFileNames, DependencyMap &Dependencies, llvm::StringRef HeaderPrefix, llvm::StringRef RootModuleName)
Create the module map file.
static cl::opt< std::string > RootModule("root-module", cl::init(""), cl::desc("Specify the name of the root module."))
static std::string ensureNoCollisionWithReservedName(llvm::StringRef MightBeReservedName)
const SymbolIndex * Index
Definition: Dexp.cpp:85