Revert "[VFS] Add support for handling path traversals"

This reverts commit r261551 due to failing tests in windows bots:

http://lab.llvm.org:8011/builders/clang-x64-ninja-win7/builds/10054

Failing Tests (4):
    Clang-Unit :: Basic/BasicTests.exe/VFSFromYAMLTest.CaseInsensitive
    Clang-Unit :: Basic/BasicTests.exe/VFSFromYAMLTest.DirectoryIteration
    Clang-Unit :: Basic/BasicTests.exe/VFSFromYAMLTest.MappedFiles
    Clang-Unit :: Basic/BasicTests.exe/VFSFromYAMLTest.UseExternalName

llvm-svn: 261654

1 files changed, 15 insertions, 39 deletions

diff --git a/clang/lib/Basic/VirtualFileSystem.cpp b/clang/lib/Basic/VirtualFileSystem.cpp
index 68ad428..6977f40 100644
--- a/clang/lib/Basic/VirtualFileSystem.cpp
+++ b/clang/lib/Basic/VirtualFileSystem.cpp
@@ -111,20 +111,6 @@ bool FileSystem::exists(const Twine &Path) {
   return Status && Status->exists();
 }
 
-#ifndef NDEBUG
-static bool isTraversalComponent(StringRef Component) {
-  return Component.equals("..") || Component.equals(".");
-}
-
-static bool pathHasTraversal(StringRef Path) {
-  using namespace llvm::sys;
-  for (StringRef Comp : llvm::make_range(path::begin(Path), path::end(Path)))
-    if (isTraversalComponent(Comp))
-      return true;
-  return false;
-}
-#endif
-
 //===-----------------------------------------------------------------------===/
 // RealFileSystem implementation
 //===-----------------------------------------------------------------------===/
@@ -821,9 +807,6 @@ public:
 ///
 /// and inherit their attributes from the external contents.
 ///
-/// Virtual file paths and external files are expected to be canonicalized
-/// without "..", "." and "./" in their paths.
-///
 /// In both cases, the 'name' field may contain multiple path components (e.g.
 /// /path/to/file). However, any directory that contains more than one child
 /// must be uniquely represented by a directory entry.
@@ -1021,13 +1004,7 @@ class RedirectingFileSystemParser {
       if (Key == "name") {
         if (!parseScalarString(I->getValue(), Value, Buffer))
           return nullptr;
-
-        SmallString<256> Path(Value);
-        // Guarantee that old YAML files containing paths with ".." and "." are
-        // properly canonicalized before read into the VFS.
-        Path = sys::path::remove_leading_dotslash(Path);
-        sys::path::remove_dots(Path, /*remove_dot_dot=*/true);
-        Name = Path.str();
+        Name = Value;
       } else if (Key == "type") {
         if (!parseScalarString(I->getValue(), Value, Buffer))
           return nullptr;
@@ -1071,12 +1048,7 @@ class RedirectingFileSystemParser {
         HasContents = true;
         if (!parseScalarString(I->getValue(), Value, Buffer))
           return nullptr;
-        SmallString<256> Path(Value);
-        // Guarantee that old YAML files containing paths with ".." and "." are
-        // properly canonicalized before read into the VFS.
-        Path = sys::path::remove_leading_dotslash(Path);
-        sys::path::remove_dots(Path, /*remove_dot_dot=*/true);
-        ExternalContentsPath = Path.str();
+        ExternalContentsPath = Value;
       } else if (Key == "use-external-name") {
         bool Val;
         if (!parseScalarBool(I->getValue(), Val))
@@ -1266,12 +1238,6 @@ ErrorOr<Entry *> RedirectingFileSystem::lookupPath(const Twine &Path_) {
   if (std::error_code EC = makeAbsolute(Path))
     return EC;
 
-  // Canonicalize path by removing ".", "..", "./", etc components. This is
-  // a VFS request, do bot bother about symlinks in the path components
-  // but canonicalize in order to perform the correct entry search.
-  Path = sys::path::remove_leading_dotslash(Path);
-  sys::path::remove_dots(Path, /*remove_dot_dot=*/true);
-
   if (Path.empty())
     return make_error_code(llvm::errc::invalid_argument);
 
@@ -1288,10 +1254,10 @@ ErrorOr<Entry *> RedirectingFileSystem::lookupPath(const Twine &Path_) {
 ErrorOr<Entry *>
 RedirectingFileSystem::lookupPath(sys::path::const_iterator Start,
                                   sys::path::const_iterator End, Entry *From) {
-  assert(!isTraversalComponent(*Start) &&
-         !isTraversalComponent(From->getName()) &&
-         "Paths should not contain traversal components");
+  if (Start->equals("."))
+    ++Start;
 
+  // FIXME: handle ..
   if (CaseSensitive ? !Start->equals(From->getName())
                     : !Start->equals_lower(From->getName()))
     // failure to match
@@ -1410,6 +1376,16 @@ UniqueID vfs::getNextVirtualUniqueID() {
   return UniqueID(std::numeric_limits<uint64_t>::max(), ID);
 }
 
+#ifndef NDEBUG
+static bool pathHasTraversal(StringRef Path) {
+  using namespace llvm::sys;
+  for (StringRef Comp : llvm::make_range(path::begin(Path), path::end(Path)))
+    if (Comp == "." || Comp == "..")
+      return true;
+  return false;
+}
+#endif
+
 void YAMLVFSWriter::addFileMapping(StringRef VirtualPath, StringRef RealPath) {
   assert(sys::path::is_absolute(VirtualPath) && "virtual path not absolute");
   assert(sys::path::is_absolute(RealPath) && "real path not absolute");