clang-tools  4.0.0
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::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 (auto I = SubModules.begin(), E = SubModules.end(); I != E; ++I) {
91  if (!(*I)->output(OS, Indent))
92  return false;
93  }
94 
95  // Output header files.
96  for (auto I = HeaderFileNames.begin(), E = HeaderFileNames.end(); I != E;
97  ++I) {
98  OS.indent(Indent);
99  if (IsProblem || strstr((*I).c_str(), ".inl"))
100  OS << "exclude header \"" << *I << "\"\n";
101  else
102  OS << "header \"" << *I << "\"\n";
103  }
104 
105  // If this module has header files, output export directive.
106  if (HeaderFileNames.size() != 0) {
107  OS.indent(Indent);
108  OS << "export *\n";
109  }
110 
111  // If this is not the nameless root module, close the module definition.
112  if (Name.size() != 0) {
113  Indent -= 2;
114  OS.indent(Indent);
115  OS << "}\n";
116  }
117 
118  return true;
119 }
120 
121 // Lookup a sub-module.
122 Module *Module::findSubModule(llvm::StringRef SubName) {
123  for (auto I = SubModules.begin(), E = SubModules.end(); I != E; ++I) {
124  if ((*I)->Name == SubName)
125  return *I;
126  }
127  return nullptr;
128 }
129 
130 // Implementation functions:
131 
132 // Reserved keywords in module.modulemap syntax.
133 // Keep in sync with keywords in module map parser in Lex/ModuleMap.cpp,
134 // such as in ModuleMapParser::consumeToken().
135 static const char *const ReservedNames[] = {
136  "config_macros", "export", "module", "conflict", "framework",
137  "requires", "exclude", "header", "private", "explicit",
138  "link", "umbrella", "extern", "use", nullptr // Flag end.
139 };
140 
141 // Convert module name to a non-keyword.
142 // Prepends a '_' to the name if and only if the name is a keyword.
143 static std::string
144 ensureNoCollisionWithReservedName(llvm::StringRef MightBeReservedName) {
145  std::string SafeName = MightBeReservedName;
146  for (int Index = 0; ReservedNames[Index] != nullptr; ++Index) {
147  if (MightBeReservedName == ReservedNames[Index]) {
148  SafeName.insert(0, "_");
149  break;
150  }
151  }
152  return SafeName;
153 }
154 
155 // Convert module name to a non-keyword.
156 // Prepends a '_' to the name if and only if the name is a keyword.
157 static std::string
158 ensureVaidModuleName(llvm::StringRef MightBeInvalidName) {
159  std::string SafeName = MightBeInvalidName;
160  std::replace(SafeName.begin(), SafeName.end(), '-', '_');
161  std::replace(SafeName.begin(), SafeName.end(), '.', '_');
162  if (isdigit(SafeName[0]))
163  SafeName = "_" + SafeName;
164  return SafeName;
165 }
166 
167 // Add one module, given a header file path.
168 static bool addModuleDescription(Module *RootModule,
169  llvm::StringRef HeaderFilePath,
170  llvm::StringRef HeaderPrefix,
171  DependencyMap &Dependencies,
172  bool IsProblemFile) {
173  Module *CurrentModule = RootModule;
174  DependentsVector &FileDependents = Dependencies[HeaderFilePath];
175  std::string FilePath;
176  // Strip prefix.
177  // HeaderFilePath should be compared to natively-canonicalized Prefix.
178  llvm::SmallString<256> NativePath, NativePrefix;
179  llvm::sys::path::native(HeaderFilePath, NativePath);
180  llvm::sys::path::native(HeaderPrefix, NativePrefix);
181  if (NativePath.startswith(NativePrefix))
182  FilePath = NativePath.substr(NativePrefix.size() + 1);
183  else
184  FilePath = HeaderFilePath;
185  int Count = FileDependents.size();
186  // Headers that go into modules must not depend on other files being
187  // included first. If there are any dependents, warn user and omit.
188  if (Count != 0) {
189  llvm::errs() << "warning: " << FilePath
190  << " depends on other headers being included first,"
191  " meaning the module.modulemap won't compile."
192  " This header will be omitted from the module map.\n";
193  return true;
194  }
195  // Make canonical.
196  std::replace(FilePath.begin(), FilePath.end(), '\\', '/');
197  // Insert module into tree, using subdirectories as submodules.
198  for (llvm::sys::path::const_iterator I = llvm::sys::path::begin(FilePath),
199  E = llvm::sys::path::end(FilePath);
200  I != E; ++I) {
201  if ((*I)[0] == '.')
202  continue;
203  std::string Stem = llvm::sys::path::stem(*I);
205  Stem = ensureVaidModuleName(Stem);
206  Module *SubModule = CurrentModule->findSubModule(Stem);
207  if (!SubModule) {
208  SubModule = new Module(Stem, IsProblemFile);
209  CurrentModule->SubModules.push_back(SubModule);
210  }
211  CurrentModule = SubModule;
212  }
213  // Add header file name to headers.
214  CurrentModule->HeaderFileNames.push_back(FilePath);
215  return true;
216 }
217 
218 // Create the internal module tree representation.
219 static Module *loadModuleDescriptions(
220  llvm::StringRef RootModuleName, llvm::ArrayRef<std::string> HeaderFileNames,
221  llvm::ArrayRef<std::string> ProblemFileNames,
222  DependencyMap &Dependencies, llvm::StringRef HeaderPrefix) {
223 
224  // Create root module.
225  auto *RootModule = new Module(RootModuleName, false);
226 
227  llvm::SmallString<256> CurrentDirectory;
228  llvm::sys::fs::current_path(CurrentDirectory);
229 
230  // If no header prefix, use current directory.
231  if (HeaderPrefix.size() == 0)
232  HeaderPrefix = CurrentDirectory;
233 
234  // Walk the header file names and output the module map.
235  for (llvm::ArrayRef<std::string>::iterator I = HeaderFileNames.begin(),
236  E = HeaderFileNames.end();
237  I != E; ++I) {
238  std::string Header(*I);
239  bool IsProblemFile = false;
240  for (auto &ProblemFile : ProblemFileNames) {
241  if (ProblemFile == Header) {
242  IsProblemFile = true;
243  break;
244  }
245  }
246  // Add as a module.
247  if (!addModuleDescription(RootModule, Header, HeaderPrefix, Dependencies, IsProblemFile))
248  return nullptr;
249  }
250 
251  return RootModule;
252 }
253 
254 // Kick off the writing of the module map.
255 static bool writeModuleMap(llvm::StringRef ModuleMapPath,
256  llvm::StringRef HeaderPrefix, Module *RootModule) {
257  llvm::SmallString<256> HeaderDirectory(ModuleMapPath);
258  llvm::sys::path::remove_filename(HeaderDirectory);
259  llvm::SmallString<256> FilePath;
260 
261  // Get the module map file path to be used.
262  if ((HeaderDirectory.size() == 0) && (HeaderPrefix.size() != 0)) {
263  FilePath = HeaderPrefix;
264  // Prepend header file name prefix if it's not absolute.
265  llvm::sys::path::append(FilePath, ModuleMapPath);
266  llvm::sys::path::native(FilePath);
267  } else {
268  FilePath = ModuleMapPath;
269  llvm::sys::path::native(FilePath);
270  }
271 
272  // Set up module map output file.
273  std::error_code EC;
274  llvm::tool_output_file Out(FilePath, EC, llvm::sys::fs::F_Text);
275  if (EC) {
276  llvm::errs() << Argv0 << ": error opening " << FilePath << ":"
277  << EC.message() << "\n";
278  return false;
279  }
280 
281  // Get output stream from tool output buffer/manager.
282  llvm::raw_fd_ostream &OS = Out.os();
283 
284  // Output file comment.
285  OS << "// " << ModuleMapPath << "\n";
286  OS << "// Generated by: " << CommandLine << "\n\n";
287 
288  // Write module hierarchy from internal representation.
289  if (!RootModule->output(OS, 0))
290  return false;
291 
292  // Tell tool_output_file that we want to keep the file.
293  Out.keep();
294 
295  return true;
296 }
297 
298 // Global functions:
299 
300 // Module map generation entry point.
301 bool createModuleMap(llvm::StringRef ModuleMapPath,
302  llvm::ArrayRef<std::string> HeaderFileNames,
303  llvm::ArrayRef<std::string> ProblemFileNames,
304  DependencyMap &Dependencies, llvm::StringRef HeaderPrefix,
305  llvm::StringRef RootModuleName) {
306  // Load internal representation of modules.
307  std::unique_ptr<Module> RootModule(
309  RootModuleName, HeaderFileNames, ProblemFileNames, Dependencies,
310  HeaderPrefix));
311  if (!RootModule.get())
312  return false;
313 
314  // Write module map file.
315  return writeModuleMap(ModuleMapPath, HeaderPrefix, RootModule.get());
316 }
const std::string Name
Definition: USRFinder.cpp:164
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 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 std::string ensureVaidModuleName(llvm::StringRef MightBeInvalidName)
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)