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Diffstat (limited to 'contrib/llvm/lib/Support/BinaryStreamWriter.cpp')
-rw-r--r-- | contrib/llvm/lib/Support/BinaryStreamWriter.cpp | 90 |
1 files changed, 90 insertions, 0 deletions
diff --git a/contrib/llvm/lib/Support/BinaryStreamWriter.cpp b/contrib/llvm/lib/Support/BinaryStreamWriter.cpp new file mode 100644 index 0000000..c427651 --- /dev/null +++ b/contrib/llvm/lib/Support/BinaryStreamWriter.cpp @@ -0,0 +1,90 @@ +//===- BinaryStreamWriter.cpp - Writes objects to a BinaryStream ----------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#include "llvm/Support/BinaryStreamWriter.h" + +#include "llvm/Support/BinaryStreamError.h" +#include "llvm/Support/BinaryStreamReader.h" +#include "llvm/Support/BinaryStreamRef.h" + +using namespace llvm; + +BinaryStreamWriter::BinaryStreamWriter(WritableBinaryStreamRef Ref) + : Stream(Ref) {} + +BinaryStreamWriter::BinaryStreamWriter(WritableBinaryStream &Stream) + : Stream(Stream) {} + +BinaryStreamWriter::BinaryStreamWriter(MutableArrayRef<uint8_t> Data, + llvm::support::endianness Endian) + : Stream(Data, Endian) {} + +Error BinaryStreamWriter::writeBytes(ArrayRef<uint8_t> Buffer) { + if (auto EC = Stream.writeBytes(Offset, Buffer)) + return EC; + Offset += Buffer.size(); + return Error::success(); +} + +Error BinaryStreamWriter::writeCString(StringRef Str) { + if (auto EC = writeFixedString(Str)) + return EC; + if (auto EC = writeObject('\0')) + return EC; + + return Error::success(); +} + +Error BinaryStreamWriter::writeFixedString(StringRef Str) { + return writeBytes(ArrayRef<uint8_t>(Str.bytes_begin(), Str.bytes_end())); +} + +Error BinaryStreamWriter::writeStreamRef(BinaryStreamRef Ref) { + return writeStreamRef(Ref, Ref.getLength()); +} + +Error BinaryStreamWriter::writeStreamRef(BinaryStreamRef Ref, uint32_t Length) { + BinaryStreamReader SrcReader(Ref.slice(0, Length)); + // This is a bit tricky. If we just call readBytes, we are requiring that it + // return us the entire stream as a contiguous buffer. There is no guarantee + // this can be satisfied by returning a reference straight from the buffer, as + // an implementation may not store all data in a single contiguous buffer. So + // we iterate over each contiguous chunk, writing each one in succession. + 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(); +} + +std::pair<BinaryStreamWriter, BinaryStreamWriter> +BinaryStreamWriter::split(uint32_t Off) const { + assert(getLength() >= Off); + + WritableBinaryStreamRef First = Stream.drop_front(Offset); + + WritableBinaryStreamRef Second = First.drop_front(Off); + First = First.keep_front(Off); + BinaryStreamWriter W1{First}; + BinaryStreamWriter W2{Second}; + return std::make_pair(W1, W2); +} + +Error BinaryStreamWriter::padToAlignment(uint32_t Align) { + uint32_t NewOffset = alignTo(Offset, Align); + if (NewOffset > getLength()) + return make_error<BinaryStreamError>(stream_error_code::stream_too_short); + while (Offset < NewOffset) + if (auto EC = writeInteger('\0')) + return EC; + return Error::success(); +} |