Frontend: Add support for reading named pipes as the main file.

 - The whole {File,Source}Manager is built around wanting to pre-determine the
   size of files, so we can't fit this in naturally. Instead, we handle it like
   we do STDIN, where we just replace the main file contents upfront.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@167419 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 13 insertions, 0 deletions

diff --git a/lib/Frontend/CompilerInstance.cpp b/lib/Frontend/CompilerInstance.cpp
index c6c5fb5fe2..b85832208b 100644
--- a/lib/Frontend/CompilerInstance.cpp
+++ b/lib/Frontend/CompilerInstance.cpp
@@ -610,6 +610,19 @@ bool CompilerInstance::InitializeSourceManager(StringRef InputFile,
       return false;
     }
     SourceMgr.createMainFileID(File, Kind);
+
+    // The natural SourceManager infrastructure can't currently handle named
+    // pipes, but we would at least like to accept them for the main
+    // file. Detect them here, read them with the more generic MemoryBuffer
+    // function, and simply override their contents as we do for STDIN.
+    if (File->isNamedPipe()) {
+      OwningPtr<llvm::MemoryBuffer> MB;
+      if (llvm::error_code ec = llvm::MemoryBuffer::getFile(InputFile, MB)) {
+        Diags.Report(diag::err_cannot_open_file) << InputFile << ec.message();
+        return false;
+      }
+      SourceMgr.overrideFileContents(File, MB.take());
+    }
   } else {
     OwningPtr<llvm::MemoryBuffer> SB;
     if (llvm::MemoryBuffer::getSTDIN(SB)) {