Add support for writing through StreamInterface.
This adds method and tests for writing to a PDB stream. With
this, even a PDB stream which is discontiguous can be treated
as a sequential stream of bytes for the purposes of writing.
Reviewed By: ruiu
Differential Revision: http://reviews.llvm.org/D21157
llvm-svn: 272369
diff --git a/llvm/lib/DebugInfo/CodeView/StreamWriter.cpp b/llvm/lib/DebugInfo/CodeView/StreamWriter.cpp
new file mode 100644
index 0000000..f61c6b5
--- /dev/null
+++ b/llvm/lib/DebugInfo/CodeView/StreamWriter.cpp
@@ -0,0 +1,77 @@
+//===- StreamWrite.cpp - Writes bytes and objects to a stream -------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/DebugInfo/CodeView/StreamWriter.h"
+
+#include "llvm/DebugInfo/CodeView/CodeViewError.h"
+#include "llvm/DebugInfo/CodeView/StreamReader.h"
+#include "llvm/DebugInfo/CodeView/StreamRef.h"
+
+using namespace llvm;
+using namespace llvm::codeview;
+
+StreamWriter::StreamWriter(StreamRef S) : Stream(S), Offset(0) {}
+
+Error StreamWriter::writeBytes(ArrayRef<uint8_t> Buffer) {
+ if (auto EC = Stream.writeBytes(Offset, Buffer))
+ return EC;
+ Offset += Buffer.size();
+ return Error::success();
+}
+
+Error StreamWriter::writeInteger(uint16_t Int) {
+ return writeObject(support::ulittle16_t(Int));
+}
+
+Error StreamWriter::writeInteger(uint32_t Int) {
+ return writeObject(support::ulittle32_t(Int));
+}
+
+Error StreamWriter::writeZeroString(StringRef Str) {
+ if (auto EC = writeFixedString(Str))
+ return EC;
+ if (auto EC = writeObject('\0'))
+ return EC;
+
+ return Error::success();
+}
+
+Error StreamWriter::writeFixedString(StringRef Str) {
+ ArrayRef<uint8_t> Bytes(Str.bytes_begin(), Str.bytes_end());
+ if (auto EC = Stream.writeBytes(Offset, Bytes))
+ return EC;
+
+ Offset += Str.size();
+ return Error::success();
+}
+
+Error StreamWriter::writeStreamRef(StreamRef Ref) {
+ if (auto EC = writeStreamRef(Ref, Ref.getLength()))
+ return EC;
+ Offset += Ref.getLength();
+ return Error::success();
+}
+
+Error StreamWriter::writeStreamRef(StreamRef Ref, uint32_t Length) {
+ Ref = Ref.slice(0, Length);
+
+ StreamReader SrcReader(Ref);
+ // This is a bit tricky. If we just call readBytes, we are requiring that it
+ // return us the entire stream as a contiguous buffer. For large streams this
+ // will allocate a huge amount of space from the pool. Instead, iterate over
+ // each contiguous chunk until we've consumed the entire stream.
+ while (SrcReader.bytesRemaining() > 0) {
+ ArrayRef<uint8_t> Chunk;
+ if (auto EC = SrcReader.readLongestContiguousChunk(Chunk))
+ return EC;
+ if (auto EC = writeBytes(Chunk))
+ return EC;
+ }
+ return Error::success();
+}