clang  6.0.0svn
CompilationDatabase.h
Go to the documentation of this file.
1 //===--- CompilationDatabase.h - --------------------------------*- 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 provides an interface and multiple implementations for
11 // CompilationDatabases.
12 //
13 // While C++ refactoring and analysis tools are not compilers, and thus
14 // don't run as part of the build system, they need the exact information
15 // of a build in order to be able to correctly understand the C++ code of
16 // the project. This information is provided via the CompilationDatabase
17 // interface.
18 //
19 // To create a CompilationDatabase from a build directory one can call
20 // CompilationDatabase::loadFromDirectory(), which deduces the correct
21 // compilation database from the root of the build tree.
22 //
23 // See the concrete subclasses of CompilationDatabase for currently supported
24 // formats.
25 //
26 //===----------------------------------------------------------------------===//
27 
28 #ifndef LLVM_CLANG_TOOLING_COMPILATIONDATABASE_H
29 #define LLVM_CLANG_TOOLING_COMPILATIONDATABASE_H
30 
31 #include "clang/Basic/LLVM.h"
32 #include "llvm/ADT/ArrayRef.h"
33 #include "llvm/ADT/StringRef.h"
34 #include "llvm/ADT/Twine.h"
35 #include <memory>
36 #include <string>
37 #include <vector>
38 
39 namespace clang {
40 namespace tooling {
41 
42 /// \brief Specifies the working directory and command of a compilation.
46  std::vector<std::string> CommandLine, Twine Output)
47  : Directory(Directory.str()),
48  Filename(Filename.str()),
49  CommandLine(std::move(CommandLine)),
50  Output(Output.str()){}
51 
52  /// \brief The working directory the command was executed from.
53  std::string Directory;
54 
55  /// The source file associated with the command.
56  std::string Filename;
57 
58  /// \brief The command line that was executed.
59  std::vector<std::string> CommandLine;
60 
61  /// The output file associated with the command.
62  std::string Output;
63 };
64 
65 /// \brief Interface for compilation databases.
66 ///
67 /// A compilation database allows the user to retrieve compile command lines
68 /// for the files in a project.
69 ///
70 /// Many implementations are enumerable, allowing all command lines to be
71 /// retrieved. These can be used to run clang tools over a subset of the files
72 /// in a project.
74 public:
75  virtual ~CompilationDatabase();
76 
77  /// \brief Loads a compilation database from a build directory.
78  ///
79  /// Looks at the specified 'BuildDirectory' and creates a compilation database
80  /// that allows to query compile commands for source files in the
81  /// corresponding source tree.
82  ///
83  /// Returns NULL and sets ErrorMessage if we were not able to build up a
84  /// compilation database for the build directory.
85  ///
86  /// FIXME: Currently only supports JSON compilation databases, which
87  /// are named 'compile_commands.json' in the given directory. Extend this
88  /// for other build types (like ninja build files).
89  static std::unique_ptr<CompilationDatabase>
90  loadFromDirectory(StringRef BuildDirectory, std::string &ErrorMessage);
91 
92  /// \brief Tries to detect a compilation database location and load it.
93  ///
94  /// Looks for a compilation database in all parent paths of file 'SourceFile'
95  /// by calling loadFromDirectory.
96  static std::unique_ptr<CompilationDatabase>
97  autoDetectFromSource(StringRef SourceFile, std::string &ErrorMessage);
98 
99  /// \brief Tries to detect a compilation database location and load it.
100  ///
101  /// Looks for a compilation database in directory 'SourceDir' and all
102  /// its parent paths by calling loadFromDirectory.
103  static std::unique_ptr<CompilationDatabase>
104  autoDetectFromDirectory(StringRef SourceDir, std::string &ErrorMessage);
105 
106  /// \brief Returns all compile commands in which the specified file was
107  /// compiled.
108  ///
109  /// This includes compile commands that span multiple source files.
110  /// For example, consider a project with the following compilations:
111  /// $ clang++ -o test a.cc b.cc t.cc
112  /// $ clang++ -o production a.cc b.cc -DPRODUCTION
113  /// A compilation database representing the project would return both command
114  /// lines for a.cc and b.cc and only the first command line for t.cc.
115  virtual std::vector<CompileCommand> getCompileCommands(
116  StringRef FilePath) const = 0;
117 
118  /// \brief Returns the list of all files available in the compilation database.
119  ///
120  /// By default, returns nothing. Implementations should override this if they
121  /// can enumerate their source files.
122  virtual std::vector<std::string> getAllFiles() const { return {}; }
123 
124  /// \brief Returns all compile commands for all the files in the compilation
125  /// database.
126  ///
127  /// FIXME: Add a layer in Tooling that provides an interface to run a tool
128  /// over all files in a compilation database. Not all build systems have the
129  /// ability to provide a feasible implementation for \c getAllCompileCommands.
130  ///
131  /// By default, this is implemented in terms of getAllFiles() and
132  /// getCompileCommands(). Subclasses may override this for efficiency.
133  virtual std::vector<CompileCommand> getAllCompileCommands() const;
134 };
135 
136 /// \brief Interface for compilation database plugins.
137 ///
138 /// A compilation database plugin allows the user to register custom compilation
139 /// databases that are picked up as compilation database if the corresponding
140 /// library is linked in. To register a plugin, declare a static variable like:
141 ///
142 /// \code
143 /// static CompilationDatabasePluginRegistry::Add<MyDatabasePlugin>
144 /// X("my-compilation-database", "Reads my own compilation database");
145 /// \endcode
147 public:
148  virtual ~CompilationDatabasePlugin();
149 
150  /// \brief Loads a compilation database from a build directory.
151  ///
152  /// \see CompilationDatabase::loadFromDirectory().
153  virtual std::unique_ptr<CompilationDatabase>
154  loadFromDirectory(StringRef Directory, std::string &ErrorMessage) = 0;
155 };
156 
157 /// \brief A compilation database that returns a single compile command line.
158 ///
159 /// Useful when we want a tool to behave more like a compiler invocation.
160 /// This compilation database is not enumerable: getAllFiles() returns {}.
162 public:
163  /// \brief Creates a FixedCompilationDatabase from the arguments after "--".
164  ///
165  /// Parses the given command line for "--". If "--" is found, the rest of
166  /// the arguments will make up the command line in the returned
167  /// FixedCompilationDatabase.
168  /// The arguments after "--" must not include positional parameters or the
169  /// argv[0] of the tool. Those will be added by the FixedCompilationDatabase
170  /// when a CompileCommand is requested. The argv[0] of the returned command
171  /// line will be "clang-tool".
172  ///
173  /// Returns NULL in case "--" is not found.
174  ///
175  /// The argument list is meant to be compatible with normal llvm command line
176  /// parsing in main methods.
177  /// int main(int argc, char **argv) {
178  /// std::unique_ptr<FixedCompilationDatabase> Compilations(
179  /// FixedCompilationDatabase::loadFromCommandLine(argc, argv));
180  /// cl::ParseCommandLineOptions(argc, argv);
181  /// ...
182  /// }
183  ///
184  /// \param Argc The number of command line arguments - will be changed to
185  /// the number of arguments before "--", if "--" was found in the argument
186  /// list.
187  /// \param Argv Points to the command line arguments.
188  /// \param ErrorMsg Contains error text if the function returns null pointer.
189  /// \param Directory The base directory used in the FixedCompilationDatabase.
190  static std::unique_ptr<FixedCompilationDatabase> loadFromCommandLine(
191  int &Argc, const char *const *Argv, std::string &ErrorMsg,
192  Twine Directory = ".");
193 
194  /// Reads flags from the given file, one-per line.
195  /// Returns nullptr and sets ErrorMessage if we can't read the file.
196  static std::unique_ptr<FixedCompilationDatabase>
197  loadFromFile(StringRef Path, std::string &ErrorMsg);
198 
199  /// \brief Constructs a compilation data base from a specified directory
200  /// and command line.
202 
203  /// \brief Returns the given compile command.
204  ///
205  /// Will always return a vector with one entry that contains the directory
206  /// and command line specified at construction with "clang-tool" as argv[0]
207  /// and 'FilePath' as positional argument.
208  std::vector<CompileCommand>
209  getCompileCommands(StringRef FilePath) const override;
210 
211 private:
212  /// This is built up to contain a single entry vector to be returned from
213  /// getCompileCommands after adding the positional argument.
214  std::vector<CompileCommand> CompileCommands;
215 };
216 
217 } // end namespace tooling
218 } // end namespace clang
219 
220 #endif
std::string Output
The output file associated with the command.
Interface for compilation database plugins.
virtual std::vector< std::string > getAllFiles() const
Returns the list of all files available in the compilation database.
Definition: Format.h:1900
std::string Directory
The working directory the command was executed from.
Forward-declares and imports various common LLVM datatypes that clang wants to use unqualified...
std::string Filename
The source file associated with the command.
Interface for compilation databases.
Specifies the working directory and command of a compilation.
Dataflow Directional Tag Classes.
std::vector< std::string > CommandLine
The command line that was executed.
CompileCommand(Twine Directory, Twine Filename, std::vector< std::string > CommandLine, Twine Output)
A compilation database that returns a single compile command line.