1 //===- DependencyScanningTool.h - clang-scan-deps service -----------------===//
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 
9 #ifndef LLVM_CLANG_TOOLING_DEPENDENCYSCANNING_DEPENDENCYSCANNINGTOOL_H
10 #define LLVM_CLANG_TOOLING_DEPENDENCYSCANNING_DEPENDENCYSCANNINGTOOL_H
11 
12 #include "clang/Tooling/DependencyScanning/DependencyScanningService.h"
13 #include "clang/Tooling/DependencyScanning/DependencyScanningWorker.h"
14 #include "clang/Tooling/DependencyScanning/ModuleDepCollector.h"
15 #include "clang/Tooling/JSONCompilationDatabase.h"
16 #include "llvm/ADT/StringSet.h"
17 #include <string>
18 
19 namespace clang {
20 namespace tooling {
21 namespace dependencies {
22 
23 /// The full dependencies and module graph for a specific input.
24 struct FullDependencies {
25   /// The identifier of the C++20 module this translation unit exports.
26   ///
27   /// If the translation unit is not a module then \c ID.ModuleName is empty.
28   ModuleID ID;
29 
30   /// A collection of absolute paths to files that this translation unit
31   /// directly depends on, not including transitive dependencies.
32   std::vector<std::string> FileDeps;
33 
34   /// A collection of prebuilt modules this translation unit directly depends
35   /// on, not including transitive dependencies.
36   std::vector<PrebuiltModuleDep> PrebuiltModuleDeps;
37 
38   /// A list of modules this translation unit directly depends on, not including
39   /// transitive dependencies.
40   ///
41   /// This may include modules with a different context hash when it can be
42   /// determined that the differences are benign for this compilation.
43   std::vector<ModuleID> ClangModuleDeps;
44 
45   /// The original command line of the TU (excluding the compiler executable).
46   std::vector<std::string> OriginalCommandLine;
47 
48   /// Get the full command line.
49   ///
50   /// \param LookupModuleOutput This function is called to fill in
51   ///                           "-fmodule-file=", "-o" and other output
52   ///                           arguments for dependencies.
53   std::vector<std::string> getCommandLine(
54       llvm::function_ref<std::string(const ModuleID &, ModuleOutputKind)>
55           LookupOutput) const;
56 
57   /// Get the full command line, excluding -fmodule-file=" arguments.
58   std::vector<std::string> getCommandLineWithoutModulePaths() const;
59 };
60 
61 struct FullDependenciesResult {
62   FullDependencies FullDeps;
63   std::vector<ModuleDeps> DiscoveredModules;
64 };
65 
66 /// The high-level implementation of the dependency discovery tool that runs on
67 /// an individual worker thread.
68 class DependencyScanningTool {
69 public:
70   /// Construct a dependency scanning tool.
71   DependencyScanningTool(DependencyScanningService &Service,
72                          llvm::IntrusiveRefCntPtr<llvm::vfs::FileSystem> FS =
73                              llvm::vfs::createPhysicalFileSystem());
74 
75   /// Print out the dependency information into a string using the dependency
76   /// file format that is specified in the options (-MD is the default) and
77   /// return it. If \p ModuleName isn't empty, this function returns the
78   /// dependency information of module \p ModuleName.
79   ///
80   /// \returns A \c StringError with the diagnostic output if clang errors
81   /// occurred, dependency file contents otherwise.
82   llvm::Expected<std::string>
83   getDependencyFile(const std::vector<std::string> &CommandLine, StringRef CWD,
84                     llvm::Optional<StringRef> ModuleName = None);
85 
86   /// Collect the full module dependency graph for the input, ignoring any
87   /// modules which have already been seen. If \p ModuleName isn't empty, this
88   /// function returns the full dependency information of module \p ModuleName.
89   ///
90   /// \param AlreadySeen This stores modules which have previously been
91   ///                    reported. Use the same instance for all calls to this
92   ///                    function for a single \c DependencyScanningTool in a
93   ///                    single build. Use a different one for different tools,
94   ///                    and clear it between builds.
95   ///
96   /// \returns a \c StringError with the diagnostic output if clang errors
97   /// occurred, \c FullDependencies otherwise.
98   llvm::Expected<FullDependenciesResult>
99   getFullDependencies(const std::vector<std::string> &CommandLine,
100                       StringRef CWD, const llvm::StringSet<> &AlreadySeen,
101                       llvm::Optional<StringRef> ModuleName = None);
102 
103 private:
104   DependencyScanningWorker Worker;
105 };
106 
107 } // end namespace dependencies
108 } // end namespace tooling
109 } // end namespace clang
110 
111 #endif // LLVM_CLANG_TOOLING_DEPENDENCYSCANNING_DEPENDENCYSCANNINGTOOL_H
112