1317017Sdim//===- BinaryStreamWriter.cpp - Writes objects to a BinaryStream ----------===// 2317017Sdim// 3353358Sdim// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4353358Sdim// See https://llvm.org/LICENSE.txt for license information. 5353358Sdim// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6317017Sdim// 7317017Sdim//===----------------------------------------------------------------------===// 8317017Sdim 9317017Sdim#include "llvm/Support/BinaryStreamWriter.h" 10317017Sdim 11317017Sdim#include "llvm/Support/BinaryStreamError.h" 12317017Sdim#include "llvm/Support/BinaryStreamReader.h" 13317017Sdim#include "llvm/Support/BinaryStreamRef.h" 14353358Sdim#include "llvm/Support/LEB128.h" 15317017Sdim 16317017Sdimusing namespace llvm; 17317017Sdim 18318681SdimBinaryStreamWriter::BinaryStreamWriter(WritableBinaryStreamRef Ref) 19318681Sdim : Stream(Ref) {} 20317017Sdim 21318681SdimBinaryStreamWriter::BinaryStreamWriter(WritableBinaryStream &Stream) 22318681Sdim : Stream(Stream) {} 23318681Sdim 24318681SdimBinaryStreamWriter::BinaryStreamWriter(MutableArrayRef<uint8_t> Data, 25318681Sdim llvm::support::endianness Endian) 26318681Sdim : Stream(Data, Endian) {} 27318681Sdim 28317017SdimError BinaryStreamWriter::writeBytes(ArrayRef<uint8_t> Buffer) { 29317017Sdim if (auto EC = Stream.writeBytes(Offset, Buffer)) 30317017Sdim return EC; 31317017Sdim Offset += Buffer.size(); 32317017Sdim return Error::success(); 33317017Sdim} 34317017Sdim 35353358SdimError BinaryStreamWriter::writeULEB128(uint64_t Value) { 36353358Sdim uint8_t EncodedBytes[10] = {0}; 37353358Sdim unsigned Size = encodeULEB128(Value, &EncodedBytes[0]); 38353358Sdim return writeBytes({EncodedBytes, Size}); 39353358Sdim} 40353358Sdim 41353358SdimError BinaryStreamWriter::writeSLEB128(int64_t Value) { 42353358Sdim uint8_t EncodedBytes[10] = {0}; 43353358Sdim unsigned Size = encodeSLEB128(Value, &EncodedBytes[0]); 44353358Sdim return writeBytes({EncodedBytes, Size}); 45353358Sdim} 46353358Sdim 47317017SdimError BinaryStreamWriter::writeCString(StringRef Str) { 48317017Sdim if (auto EC = writeFixedString(Str)) 49317017Sdim return EC; 50317017Sdim if (auto EC = writeObject('\0')) 51317017Sdim return EC; 52317017Sdim 53317017Sdim return Error::success(); 54317017Sdim} 55317017Sdim 56317017SdimError BinaryStreamWriter::writeFixedString(StringRef Str) { 57327952Sdim 58327952Sdim return writeBytes(arrayRefFromStringRef(Str)); 59317017Sdim} 60317017Sdim 61317017SdimError BinaryStreamWriter::writeStreamRef(BinaryStreamRef Ref) { 62317017Sdim return writeStreamRef(Ref, Ref.getLength()); 63317017Sdim} 64317017Sdim 65317017SdimError BinaryStreamWriter::writeStreamRef(BinaryStreamRef Ref, uint32_t Length) { 66317017Sdim BinaryStreamReader SrcReader(Ref.slice(0, Length)); 67317017Sdim // This is a bit tricky. If we just call readBytes, we are requiring that it 68317017Sdim // return us the entire stream as a contiguous buffer. There is no guarantee 69317017Sdim // this can be satisfied by returning a reference straight from the buffer, as 70317017Sdim // an implementation may not store all data in a single contiguous buffer. So 71317017Sdim // we iterate over each contiguous chunk, writing each one in succession. 72317017Sdim while (SrcReader.bytesRemaining() > 0) { 73317017Sdim ArrayRef<uint8_t> Chunk; 74317017Sdim if (auto EC = SrcReader.readLongestContiguousChunk(Chunk)) 75317017Sdim return EC; 76317017Sdim if (auto EC = writeBytes(Chunk)) 77317017Sdim return EC; 78317017Sdim } 79317017Sdim return Error::success(); 80317017Sdim} 81317017Sdim 82317778Sdimstd::pair<BinaryStreamWriter, BinaryStreamWriter> 83317778SdimBinaryStreamWriter::split(uint32_t Off) const { 84317778Sdim assert(getLength() >= Off); 85317778Sdim 86317778Sdim WritableBinaryStreamRef First = Stream.drop_front(Offset); 87317778Sdim 88317778Sdim WritableBinaryStreamRef Second = First.drop_front(Off); 89317778Sdim First = First.keep_front(Off); 90317778Sdim BinaryStreamWriter W1{First}; 91317778Sdim BinaryStreamWriter W2{Second}; 92317778Sdim return std::make_pair(W1, W2); 93317778Sdim} 94317778Sdim 95317017SdimError BinaryStreamWriter::padToAlignment(uint32_t Align) { 96317017Sdim uint32_t NewOffset = alignTo(Offset, Align); 97317017Sdim if (NewOffset > getLength()) 98317017Sdim return make_error<BinaryStreamError>(stream_error_code::stream_too_short); 99320041Sdim while (Offset < NewOffset) 100320041Sdim if (auto EC = writeInteger('\0')) 101320041Sdim return EC; 102317017Sdim return Error::success(); 103317017Sdim} 104