Add a driver option -ivfsoverlay
Reads the description of a virtual filesystem from a file and overlays
it over the real file system.
llvm-svn: 202176
diff --git a/clang/lib/Frontend/FrontendAction.cpp b/clang/lib/Frontend/FrontendAction.cpp
index 72377d8..6cfa121 100644
--- a/clang/lib/Frontend/FrontendAction.cpp
+++ b/clang/lib/Frontend/FrontendAction.cpp
@@ -211,6 +211,32 @@
return true;
}
+ if (!CI.getHeaderSearchOpts().VFSOverlayFiles.empty()) {
+ IntrusiveRefCntPtr<vfs::OverlayFileSystem>
+ Overlay(new vfs::OverlayFileSystem(vfs::getRealFileSystem()));
+ // earlier vfs files are on the bottom
+ const std::vector<std::string> &Files =
+ CI.getHeaderSearchOpts().VFSOverlayFiles;
+ for (std::vector<std::string>::const_iterator I = Files.begin(),
+ E = Files.end();
+ I != E; ++I) {
+ OwningPtr<llvm::MemoryBuffer> Buffer;
+ if (llvm::errc::success != llvm::MemoryBuffer::getFile(*I, Buffer)) {
+ CI.getDiagnostics().Report(diag::err_missing_vfs_overlay_file) << *I;
+ goto failure;
+ }
+
+ IntrusiveRefCntPtr<vfs::FileSystem> FS =
+ vfs::getVFSFromYAML(Buffer.take(), /*DiagHandler*/0);
+ if (!FS.getPtr()) {
+ CI.getDiagnostics().Report(diag::err_invalid_vfs_overlay) << *I;
+ goto failure;
+ }
+ Overlay->pushOverlay(FS);
+ }
+ CI.setVirtualFileSystem(Overlay);
+ }
+
// Set up the file and source managers, if needed.
if (!CI.hasFileManager())
CI.createFileManager();