clang-tools  3.8.0
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::tool_output_file 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  ~Module();
51  bool output(llvm::raw_fd_ostream &OS, int Indent);
52  Module *findSubModule(llvm::StringRef SubName);
53 
54 public:
55  std::string Name;
56  std::vector<std::string> HeaderFileNames;
57  std::vector<Module *> SubModules;
58  bool IsProblem;
59 };
60 
61 } // end anonymous namespace.
62 
63 // Module functions:
64 
65 // Constructors.
66 Module::Module(llvm::StringRef Name, bool Problem)
67  : Name(Name), IsProblem(Problem) {}
68 Module::Module() : IsProblem(false) {}
69 
70 // Destructor.
71 Module::~Module() {
72  // Free submodules.
73  while (!SubModules.empty()) {
74  Module *last = SubModules.back();
75  SubModules.pop_back();
76  delete last;
77  }
78 }
79 
80 // Write a module hierarchy to the given output stream.
81 bool Module::output(llvm::raw_fd_ostream &OS, int Indent) {
82  // If this is not the nameless root module, start a module definition.
83  if (Name.size() != 0) {
84  OS.indent(Indent);
85  OS << "module " << Name << " {\n";
86  Indent += 2;
87  }
88 
89  // Output submodules.
90  for (std::vector<Module *>::iterator I = SubModules.begin(),
91  E = SubModules.end();
92  I != E; ++I) {
93  if (!(*I)->output(OS, Indent))
94  return false;
95  }
96 
97  // Output header files.
98  for (std::vector<std::string>::iterator I = HeaderFileNames.begin(),
99  E = HeaderFileNames.end();
100  I != E; ++I) {
101  OS.indent(Indent);
102  if (IsProblem)
103  OS << "exclude header \"" << *I << "\"\n";
104  else
105  OS << "header \"" << *I << "\"\n";
106  }
107 
108  // If this module has header files, output export directive.
109  if (HeaderFileNames.size() != 0) {
110  OS.indent(Indent);
111  OS << "export *\n";
112  }
113 
114  // If this is not the nameless root module, close the module definition.
115  if (Name.size() != 0) {
116  Indent -= 2;
117  OS.indent(Indent);
118  OS << "}\n";
119  }
120 
121  return true;
122 }
123 
124 // Lookup a sub-module.
125 Module *Module::findSubModule(llvm::StringRef SubName) {
126  for (std::vector<Module *>::iterator I = SubModules.begin(),
127  E = SubModules.end();
128  I != E; ++I) {
129  if ((*I)->Name == SubName)
130  return *I;
131  }
132  return nullptr;
133 }
134 
135 // Implementation functions:
136 
137 // Reserved keywords in module.modulemap syntax.
138 // Keep in sync with keywords in module map parser in Lex/ModuleMap.cpp,
139 // such as in ModuleMapParser::consumeToken().
140 static const char *const ReservedNames[] = {
141  "config_macros", "export", "module", "conflict", "framework",
142  "requires", "exclude", "header", "private", "explicit",
143  "link", "umbrella", "extern", "use", nullptr // Flag end.
144 };
145 
146 // Convert module name to a non-keyword.
147 // Prepends a '_' to the name if and only if the name is a keyword.
148 static std::string
149 ensureNoCollisionWithReservedName(llvm::StringRef MightBeReservedName) {
150  std::string SafeName = MightBeReservedName;
151  for (int Index = 0; ReservedNames[Index] != nullptr; ++Index) {
152  if (MightBeReservedName == ReservedNames[Index]) {
153  SafeName.insert(0, "_");
154  break;
155  }
156  }
157  return SafeName;
158 }
159 
160 // Add one module, given a header file path.
161 static bool addModuleDescription(Module *RootModule,
162  llvm::StringRef HeaderFilePath,
163  llvm::StringRef HeaderPrefix,
164  DependencyMap &Dependencies,
165  bool IsProblemFile) {
166  Module *CurrentModule = RootModule;
167  DependentsVector &FileDependents = Dependencies[HeaderFilePath];
168  std::string FilePath;
169  // Strip prefix.
170  // HeaderFilePath should be compared to natively-canonicalized Prefix.
171  llvm::SmallString<256> NativePath, NativePrefix;
172  llvm::sys::path::native(HeaderFilePath, NativePath);
173  llvm::sys::path::native(HeaderPrefix, NativePrefix);
174  if (NativePath.startswith(NativePrefix))
175  FilePath = NativePath.substr(NativePrefix.size() + 1);
176  else
177  FilePath = HeaderFilePath;
178  int Count = FileDependents.size();
179  // Headers that go into modules must not depend on other files being
180  // included first. If there are any dependents, warn user and omit.
181  if (Count != 0) {
182  llvm::errs() << "warning: " << FilePath
183  << " depends on other headers being included first,"
184  " meaning the module.modulemap won't compile."
185  " This header will be omitted from the module map.\n";
186  return true;
187  }
188  // Make canonical.
189  std::replace(FilePath.begin(), FilePath.end(), '\\', '/');
190  // Insert module into tree, using subdirectories as submodules.
191  for (llvm::sys::path::const_iterator I = llvm::sys::path::begin(FilePath),
192  E = llvm::sys::path::end(FilePath);
193  I != E; ++I) {
194  if ((*I)[0] == '.')
195  continue;
196  std::string Stem = llvm::sys::path::stem(*I);
198  Module *SubModule = CurrentModule->findSubModule(Stem);
199  if (!SubModule) {
200  SubModule = new Module(Stem, IsProblemFile);
201  CurrentModule->SubModules.push_back(SubModule);
202  }
203  CurrentModule = SubModule;
204  }
205  // Add header file name to headers.
206  CurrentModule->HeaderFileNames.push_back(FilePath);
207  return true;
208 }
209 
210 // Create the internal module tree representation.
211 static Module *loadModuleDescriptions(
212  llvm::StringRef RootModuleName, llvm::ArrayRef<std::string> HeaderFileNames,
213  llvm::ArrayRef<std::string> ProblemFileNames,
214  DependencyMap &Dependencies, llvm::StringRef HeaderPrefix) {
215 
216  // Create root module.
217  Module *RootModule = new Module(RootModuleName, false);
218 
219  llvm::SmallString<256> CurrentDirectory;
220  llvm::sys::fs::current_path(CurrentDirectory);
221 
222  // If no header prefix, use current directory.
223  if (HeaderPrefix.size() == 0)
224  HeaderPrefix = CurrentDirectory;
225 
226  // Walk the header file names and output the module map.
227  for (llvm::ArrayRef<std::string>::iterator I = HeaderFileNames.begin(),
228  E = HeaderFileNames.end();
229  I != E; ++I) {
230  std::string Header(*I);
231  bool IsProblemFile = false;
232  for (auto &ProblemFile : ProblemFileNames) {
233  if (ProblemFile == Header) {
234  IsProblemFile = true;
235  break;
236  }
237  }
238  // Add as a module.
239  if (!addModuleDescription(RootModule, Header, HeaderPrefix, Dependencies, IsProblemFile))
240  return nullptr;
241  }
242 
243  return RootModule;
244 }
245 
246 // Kick off the writing of the module map.
247 static bool writeModuleMap(llvm::StringRef ModuleMapPath,
248  llvm::StringRef HeaderPrefix, Module *RootModule) {
249  llvm::SmallString<256> HeaderDirectory(ModuleMapPath);
250  llvm::sys::path::remove_filename(HeaderDirectory);
251  llvm::SmallString<256> FilePath;
252 
253  // Get the module map file path to be used.
254  if ((HeaderDirectory.size() == 0) && (HeaderPrefix.size() != 0)) {
255  FilePath = HeaderPrefix;
256  // Prepend header file name prefix if it's not absolute.
257  llvm::sys::path::append(FilePath, ModuleMapPath);
258  llvm::sys::path::native(FilePath);
259  } else {
260  FilePath = ModuleMapPath;
261  llvm::sys::path::native(FilePath);
262  }
263 
264  // Set up module map output file.
265  std::error_code EC;
266  llvm::tool_output_file Out(FilePath, EC, llvm::sys::fs::F_Text);
267  if (EC) {
268  llvm::errs() << Argv0 << ": error opening " << FilePath << ":"
269  << EC.message() << "\n";
270  return false;
271  }
272 
273  // Get output stream from tool output buffer/manager.
274  llvm::raw_fd_ostream &OS = Out.os();
275 
276  // Output file comment.
277  OS << "// " << ModuleMapPath << "\n";
278  OS << "// Generated by: " << CommandLine << "\n\n";
279 
280  // Write module hierarchy from internal representation.
281  if (!RootModule->output(OS, 0))
282  return false;
283 
284  // Tell tool_output_file that we want to keep the file.
285  Out.keep();
286 
287  return true;
288 }
289 
290 // Global functions:
291 
292 // Module map generation entry point.
293 bool createModuleMap(llvm::StringRef ModuleMapPath,
294  llvm::ArrayRef<std::string> HeaderFileNames,
295  llvm::ArrayRef<std::string> ProblemFileNames,
296  DependencyMap &Dependencies, llvm::StringRef HeaderPrefix,
297  llvm::StringRef RootModuleName) {
298  // Load internal representation of modules.
299  std::unique_ptr<Module> RootModule(
301  RootModuleName, HeaderFileNames, ProblemFileNames, Dependencies,
302  HeaderPrefix));
303  if (!RootModule.get())
304  return false;
305 
306  // Write module map file.
307  return writeModuleMap(ModuleMapPath, HeaderPrefix, RootModule.get());
308 }
Common definitions for Modularize.
static bool addModuleDescription(Module *RootModule, llvm::StringRef HeaderFilePath, llvm::StringRef HeaderPrefix, DependencyMap &Dependencies, bool IsProblemFile)
StringHandle Name
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 cl::opt< std::string > HeaderPrefix("prefix", cl::init(""), cl::desc("Prepend header file paths with this prefix."" If not specified,"" the files are considered to be relative to the header list file."))
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."))
std::string CommandLine
Definition: Modularize.cpp:336
llvm::StringMap< DependentsVector > DependencyMap
Definition: Modularize.h:33
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)