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, 6 insertions, 5 deletions

diff --git a/clang/lib/Lex/HeaderSearch.cpp b/clang/lib/Lex/HeaderSearch.cpp
index c475336ca5b..27eca0a81c4 100644
--- a/clang/lib/Lex/HeaderSearch.cpp
+++ b/clang/lib/Lex/HeaderSearch.cpp
@@ -17,7 +17,6 @@
 #include "clang/Basic/IdentifierTable.h"
 #include "clang/Basic/Module.h"
 #include "clang/Basic/SourceManager.h"
-#include "clang/Basic/VirtualFileSystem.h"
 #include "clang/Lex/DirectoryLookup.h"
 #include "clang/Lex/ExternalPreprocessorSource.h"
 #include "clang/Lex/HeaderMap.h"
@@ -35,6 +34,7 @@
 #include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/FileSystem.h"
 #include "llvm/Support/Path.h"
+#include "llvm/Support/VirtualFileSystem.h"
 #include <algorithm>
 #include <cassert>
 #include <cstddef>
@@ -1571,8 +1571,9 @@ void HeaderSearch::collectAllModules(SmallVectorImpl<Module *> &Modules) {
                                 DirNative);
 
         // Search each of the ".framework" directories to load them as modules.
-        vfs::FileSystem &FS = *FileMgr.getVirtualFileSystem();
-        for (vfs::directory_iterator Dir = FS.dir_begin(DirNative, EC), DirEnd;
+        llvm::vfs::FileSystem &FS = *FileMgr.getVirtualFileSystem();
+        for (llvm::vfs::directory_iterator Dir = FS.dir_begin(DirNative, EC),
+                                           DirEnd;
              Dir != DirEnd && !EC; Dir.increment(EC)) {
           if (llvm::sys::path::extension(Dir->path()) != ".framework")
             continue;
@@ -1639,8 +1640,8 @@ void HeaderSearch::loadSubdirectoryModuleMaps(DirectoryLookup &SearchDir) {
   std::error_code EC;
   SmallString<128> DirNative;
   llvm::sys::path::native(SearchDir.getDir()->getName(), DirNative);
-  vfs::FileSystem &FS = *FileMgr.getVirtualFileSystem();
-  for (vfs::directory_iterator Dir = FS.dir_begin(DirNative, EC), DirEnd;
+  llvm::vfs::FileSystem &FS = *FileMgr.getVirtualFileSystem();
+  for (llvm::vfs::directory_iterator Dir = FS.dir_begin(DirNative, EC), DirEnd;
        Dir != DirEnd && !EC; Dir.increment(EC)) {
     bool IsFramework = llvm::sys::path::extension(Dir->path()) == ".framework";
     if (IsFramework == SearchDir.isFramework())