Implement -working-directory.

When -working-directory is passed in command line, file paths are resolved relative to the specified directory.
This helps both when using libclang (where we can't require the user to actually change the working directory)
and to help reproduce test cases when the reproduction work comes along.

--FileSystemOptions is introduced which controls how file system operations are performed (currently it just contains
 the working directory value if set).
--FileSystemOptions are passed around to various interfaces that perform file operations.
--Opening & reading the content of files should be done only through FileManager. This is useful in general since
 file operations will be abstracted in the future for the reproduction mechanism.

FileSystemOptions is independent of FileManager so that we can have multiple translation units sharing the same
FileManager but with different FileSystemOptions.

Addresses rdar://8583824.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@118203 91177308-0d34-0410-b5e6-96231b3b80d8

4 files changed, 32 insertions, 3 deletions

diff --git a/include/clang/Frontend/ASTUnit.h b/include/clang/Frontend/ASTUnit.h
index 45f771763d..980cd54cb3 100644
--- a/include/clang/Frontend/ASTUnit.h
+++ b/include/clang/Frontend/ASTUnit.h
@@ -21,6 +21,7 @@
 #include "clang/Lex/PreprocessingRecord.h"
 #include "clang/Basic/SourceManager.h"
 #include "clang/Basic/FileManager.h"
+#include "clang/Basic/FileSystemOptions.h"
 #include "clang-c/Index.h"
 #include "llvm/ADT/IntrusiveRefCntPtr.h"
 #include "llvm/ADT/OwningPtr.h"
@@ -68,7 +69,9 @@ private:
   llvm::OwningPtr<TargetInfo>       Target;
   llvm::OwningPtr<Preprocessor>     PP;
   llvm::OwningPtr<ASTContext>       Ctx;
-  
+
+  FileSystemOptions FileSystemOpts;
+
   /// \brief The AST consumer that received information about the translation
   /// unit as it was parsed or loaded.
   llvm::OwningPtr<ASTConsumer> Consumer;
@@ -359,6 +362,8 @@ public:
   const FileManager &getFileManager() const { return *FileMgr; }
         FileManager &getFileManager()       { return *FileMgr; }
 
+  const FileSystemOptions &getFileSystemOpts() const { return FileSystemOpts; }
+
   const std::string &getOriginalSourceFileName();
   const std::string &getASTFileName();
 
@@ -452,7 +457,12 @@ public:
   unsigned cached_completion_size() const { 
     return CachedCompletionResults.size(); 
   }
-  
+
+  llvm::MemoryBuffer *getBufferForFile(llvm::StringRef Filename,
+                                       std::string *ErrorStr = 0,
+                                       int64_t FileSize = -1,
+                                       struct stat *FileInfo = 0);
+
   /// \brief Whether this AST represents a complete translation unit.
   ///
   /// If false, this AST is only a partial translation unit, e.g., one
@@ -473,6 +483,7 @@ public:
   /// \returns - The initialized ASTUnit or null if the AST failed to load.
   static ASTUnit *LoadFromASTFile(const std::string &Filename,
                                   llvm::IntrusiveRefCntPtr<Diagnostic> Diags,
+                                  const FileSystemOptions &FileSystemOpts,
                                   bool OnlyLocalDecls = false,
                                   RemappedFile *RemappedFiles = 0,
                                   unsigned NumRemappedFiles = 0,
diff --git a/include/clang/Frontend/CompilerInstance.h b/include/clang/Frontend/CompilerInstance.h
index e5121e1bf9..3db6077029 100644
--- a/include/clang/Frontend/CompilerInstance.h
+++ b/include/clang/Frontend/CompilerInstance.h
@@ -220,6 +220,10 @@ public:
     return Invocation->getDiagnosticOpts();
   }
 
+  const FileSystemOptions &getFileSystemOpts() const {
+    return Invocation->getFileSystemOpts();
+  }
+
   FrontendOptions &getFrontendOpts() {
     return Invocation->getFrontendOpts();
   }
@@ -499,7 +503,8 @@ public:
   void createFileManager();
 
   /// Create the source manager and replace any existing one with it.
-  void createSourceManager();
+  void createSourceManager(FileManager &FileMgr,
+                           const FileSystemOptions &FSOpts);
 
   /// Create the preprocessor, using the invocation, file, and source managers,
   /// and replace any existing one with it.
@@ -517,6 +522,7 @@ public:
                                           const DependencyOutputOptions &,
                                           const TargetInfo &,
                                           const FrontendOptions &,
+                                          const FileSystemOptions &,
                                           SourceManager &, FileManager &);
 
   /// Create the AST context.
@@ -617,6 +623,7 @@ public:
   static bool InitializeSourceManager(llvm::StringRef InputFile,
                                       Diagnostic &Diags,
                                       FileManager &FileMgr,
+                                      const FileSystemOptions &FSOpts,
                                       SourceManager &SourceMgr,
                                       const FrontendOptions &Opts);
 
diff --git a/include/clang/Frontend/CompilerInvocation.h b/include/clang/Frontend/CompilerInvocation.h
index aef02448f0..641c5f6650 100644
--- a/include/clang/Frontend/CompilerInvocation.h
+++ b/include/clang/Frontend/CompilerInvocation.h
@@ -12,6 +12,7 @@
 
 #include "clang/Basic/LangOptions.h"
 #include "clang/Basic/TargetOptions.h"
+#include "clang/Basic/FileSystemOptions.h"
 #include "clang/Frontend/AnalyzerOptions.h"
 #include "clang/Frontend/CodeGenOptions.h"
 #include "clang/Frontend/DependencyOutputOptions.h"
@@ -52,6 +53,9 @@ class CompilerInvocation {
   /// Options controlling the diagnostic engine.
   DiagnosticOptions DiagnosticOpts;
 
+  /// Options controlling file system operations.
+  FileSystemOptions FileSystemOpts;
+
   /// Options controlling the frontend itself.
   FrontendOptions FrontendOpts;
 
@@ -126,6 +130,11 @@ public:
   DiagnosticOptions &getDiagnosticOpts() { return DiagnosticOpts; }
   const DiagnosticOptions &getDiagnosticOpts() const { return DiagnosticOpts; }
 
+  FileSystemOptions &getFileSystemOpts() { return FileSystemOpts; }
+  const FileSystemOptions &getFileSystemOpts() const {
+    return FileSystemOpts;
+  }
+
   HeaderSearchOptions &getHeaderSearchOpts() { return HeaderSearchOpts; }
   const HeaderSearchOptions &getHeaderSearchOpts() const {
     return HeaderSearchOpts;
diff --git a/include/clang/Frontend/Utils.h b/include/clang/Frontend/Utils.h
index fe722db381..ff075445b4 100644
--- a/include/clang/Frontend/Utils.h
+++ b/include/clang/Frontend/Utils.h
@@ -39,6 +39,7 @@ class SourceManager;
 class Stmt;
 class TargetInfo;
 class FrontendOptions;
+class FileSystemOptions;
 
 /// Normalize \arg File for use in a user defined #include directive (in the
 /// predefines buffer).
@@ -53,6 +54,7 @@ void ApplyHeaderSearchOptions(HeaderSearch &HS,
 /// InitializePreprocessor - Initialize the preprocessor getting it and the
 /// environment ready to process a single file.
 void InitializePreprocessor(Preprocessor &PP,
+                            const FileSystemOptions &FSOpts,
                             const PreprocessorOptions &PPOpts,
                             const HeaderSearchOptions &HSOpts,
                             const FrontendOptions &FEOpts);