Fix a relatively nasty bug with fs::getPathFromOpenFD() on Windows. The GetFinalPathNameByHandle API does not behave as documented; if given a buffer that has enough space for the path but not the null terminator, the call will return the number of characters required *without* the null terminator (despite being documented otherwise) and it will not set GetLastError(). The result was that this function would return a bogus path and no error. Instead, ensure there is sufficient space for a null terminator (we already strip it off manually for compatibility with older versions of Windows).
llvm-svn: 273195
diff --git a/llvm/unittests/Support/Path.cpp b/llvm/unittests/Support/Path.cpp
index 705a90b..74b74ac 100644
--- a/llvm/unittests/Support/Path.cpp
+++ b/llvm/unittests/Support/Path.cpp
@@ -1024,6 +1024,39 @@
::close(FileDescriptor);
}
+TEST_F(FileSystemTest, PathFromFDWin32) {
+ // Create a temp file.
+ int FileDescriptor;
+ SmallString<64> TempPath;
+ ASSERT_NO_ERROR(
+ fs::createTemporaryFile("prefix", "temp", FileDescriptor, TempPath));
+
+ // Make sure it exists.
+ ASSERT_TRUE(sys::fs::exists(Twine(TempPath)));
+
+ SmallVector<char, 8> ResultPath;
+ std::error_code ErrorCode =
+ fs::getPathFromOpenFD(FileDescriptor, ResultPath);
+
+ if (!ErrorCode) {
+ // Now that we know how much space is required for the path, create a path
+ // buffer with exactly enough space (sans null terminator, which should not
+ // be present), and call getPathFromOpenFD again to ensure that the API
+ // properly handles exactly-sized buffers.
+ SmallVector<char, 8> ExactSizedPath(ResultPath.size());
+ ErrorCode = fs::getPathFromOpenFD(FileDescriptor, ExactSizedPath);
+ ResultPath = ExactSizedPath;
+ }
+
+ if (!ErrorCode) {
+ fs::UniqueID D1, D2;
+ ASSERT_NO_ERROR(fs::getUniqueID(Twine(TempPath), D1));
+ ASSERT_NO_ERROR(fs::getUniqueID(Twine(ResultPath), D2));
+ ASSERT_EQ(D1, D2);
+ }
+ ::close(FileDescriptor);
+}
+
TEST_F(FileSystemTest, OpenFileForRead) {
// Create a temp file.
int FileDescriptor;