diff options
author | Dimitry Andric <dim@FreeBSD.org> | 2019-12-20 19:53:05 +0000 |
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committer | Dimitry Andric <dim@FreeBSD.org> | 2019-12-20 19:53:05 +0000 |
commit | 0b57cec536236d46e3dba9bd041533462f33dbb7 (patch) | |
tree | 56229dbdbbf76d18580f72f789003db17246c8d9 /contrib/llvm-project/llvm/lib/Support/BinaryStreamWriter.cpp | |
parent | 718ef55ec7785aae63f98f8ca05dc07ed399c16d (diff) |
Notes
Diffstat (limited to 'contrib/llvm-project/llvm/lib/Support/BinaryStreamWriter.cpp')
-rw-r--r-- | contrib/llvm-project/llvm/lib/Support/BinaryStreamWriter.cpp | 103 |
1 files changed, 103 insertions, 0 deletions
diff --git a/contrib/llvm-project/llvm/lib/Support/BinaryStreamWriter.cpp b/contrib/llvm-project/llvm/lib/Support/BinaryStreamWriter.cpp new file mode 100644 index 000000000000..986e18da281d --- /dev/null +++ b/contrib/llvm-project/llvm/lib/Support/BinaryStreamWriter.cpp @@ -0,0 +1,103 @@ +//===- BinaryStreamWriter.cpp - Writes objects to a BinaryStream ----------===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// + +#include "llvm/Support/BinaryStreamWriter.h" + +#include "llvm/Support/BinaryStreamError.h" +#include "llvm/Support/BinaryStreamReader.h" +#include "llvm/Support/BinaryStreamRef.h" +#include "llvm/Support/LEB128.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::writeULEB128(uint64_t Value) { + uint8_t EncodedBytes[10] = {0}; + unsigned Size = encodeULEB128(Value, &EncodedBytes[0]); + return writeBytes({EncodedBytes, Size}); +} + +Error BinaryStreamWriter::writeSLEB128(int64_t Value) { + uint8_t EncodedBytes[10] = {0}; + unsigned Size = encodeSLEB128(Value, &EncodedBytes[0]); + return writeBytes({EncodedBytes, Size}); +} + +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(arrayRefFromStringRef(Str)); +} + +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(); +} |