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.

llvm-svn: 118203

1 files changed, 4 insertions, 2 deletions

diff --git a/clang/lib/Lex/PTHLexer.cpp b/clang/lib/Lex/PTHLexer.cpp
index 63b4823cf19..3d52159fa3b 100644
--- a/clang/lib/Lex/PTHLexer.cpp
+++ b/clang/lib/Lex/PTHLexer.cpp
@@ -434,10 +434,12 @@ static void InvalidPTH(Diagnostic &Diags, const char *Msg) {
   Diags.Report(Diags.getCustomDiagID(Diagnostic::Error, Msg));
 }
 
-PTHManager* PTHManager::Create(const std::string& file, Diagnostic &Diags) {
+PTHManager* PTHManager::Create(const std::string& file, FileManager &FileMgr,
+                               const FileSystemOptions &FSOpts,
+                               Diagnostic &Diags) {
   // Memory map the PTH file.
   llvm::OwningPtr<llvm::MemoryBuffer>
-  File(llvm::MemoryBuffer::getFile(file.c_str()));
+  File(FileMgr.getBufferForFile(file, FSOpts));
 
   if (!File) {
     Diags.Report(diag::err_invalid_pth_file) << file;