Lift VFS from clang to llvm (NFC)

This patch moves the virtual file system form clang to llvm so it can be
used by more projects.

Concretely the patch:
 - Moves VirtualFileSystem.{h|cpp} from clang/Basic to llvm/Support.
 - Moves the corresponding unit test from clang to llvm.
 - Moves the vfs namespace from clang::vfs to llvm::vfs.
 - Formats the lines affected by this change, mostly this is the result of
   the added llvm namespace.

RFC on the mailing list:
http://lists.llvm.org/pipermail/llvm-dev/2018-October/126657.html

Differential revision: https://reviews.llvm.org/D52783

llvm-svn: 344140

1 files changed, 8 insertions, 6 deletions

diff --git a/clang/lib/Lex/ModuleMap.cpp b/clang/lib/Lex/ModuleMap.cpp
index b6a6e26d6ad..d44bf124ffc 100644
--- a/clang/lib/Lex/ModuleMap.cpp
+++ b/clang/lib/Lex/ModuleMap.cpp
@@ -22,7 +22,6 @@
 #include "clang/Basic/SourceLocation.h"
 #include "clang/Basic/SourceManager.h"
 #include "clang/Basic/TargetInfo.h"
-#include "clang/Basic/VirtualFileSystem.h"
 #include "clang/Lex/HeaderSearch.h"
 #include "clang/Lex/HeaderSearchOptions.h"
 #include "clang/Lex/LexDiagnostic.h"
@@ -43,6 +42,7 @@
 #include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/MemoryBuffer.h"
 #include "llvm/Support/Path.h"
+#include "llvm/Support/VirtualFileSystem.h"
 #include "llvm/Support/raw_ostream.h"
 #include <algorithm>
 #include <cassert>
@@ -1020,9 +1020,10 @@ Module *ModuleMap::inferFrameworkModule(const DirectoryEntry *FrameworkDir,
     = StringRef(FrameworkDir->getName());
   llvm::sys::path::append(SubframeworksDirName, "Frameworks");
   llvm::sys::path::native(SubframeworksDirName);
-  vfs::FileSystem &FS = *FileMgr.getVirtualFileSystem();
-  for (vfs::directory_iterator Dir = FS.dir_begin(SubframeworksDirName, EC),
-                               DirEnd;
+  llvm::vfs::FileSystem &FS = *FileMgr.getVirtualFileSystem();
+  for (llvm::vfs::directory_iterator
+           Dir = FS.dir_begin(SubframeworksDirName, EC),
+           DirEnd;
        Dir != DirEnd && !EC; Dir.increment(EC)) {
     if (!StringRef(Dir->path()).endswith(".framework"))
       continue;
@@ -2394,8 +2395,9 @@ void ModuleMapParser::parseUmbrellaDirDecl(SourceLocation UmbrellaLoc) {
     // uncommonly used Tcl module on Darwin platforms.
     std::error_code EC;
     SmallVector<Module::Header, 6> Headers;
-    vfs::FileSystem &FS = *SourceMgr.getFileManager().getVirtualFileSystem();
-    for (vfs::recursive_directory_iterator I(FS, Dir->getName(), EC), E;
+    llvm::vfs::FileSystem &FS =
+        *SourceMgr.getFileManager().getVirtualFileSystem();
+    for (llvm::vfs::recursive_directory_iterator I(FS, Dir->getName(), EC), E;
          I != E && !EC; I.increment(EC)) {
       if (const FileEntry *FE = SourceMgr.getFileManager().getFile(I->path())) {