1 //===- BinaryStreamWriter.cpp - Writes objects to a BinaryStream ----------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 10 #include "llvm/Support/BinaryStreamWriter.h" 11 12 #include "llvm/Support/BinaryStreamReader.h" 13 #include "llvm/Support/BinaryStreamRef.h" 14 15 using namespace llvm; 16 17 BinaryStreamWriter::BinaryStreamWriter(WritableBinaryStreamRef S) 18 : Stream(S), Offset(0) {} 19 20 Error BinaryStreamWriter::writeBytes(ArrayRef<uint8_t> Buffer) { 21 if (auto EC = Stream.writeBytes(Offset, Buffer)) 22 return EC; 23 Offset += Buffer.size(); 24 return Error::success(); 25 } 26 27 Error BinaryStreamWriter::writeCString(StringRef Str) { 28 if (auto EC = writeFixedString(Str)) 29 return EC; 30 if (auto EC = writeObject('\0')) 31 return EC; 32 33 return Error::success(); 34 } 35 36 Error BinaryStreamWriter::writeFixedString(StringRef Str) { 37 return writeBytes(ArrayRef<uint8_t>(Str.bytes_begin(), Str.bytes_end())); 38 } 39 40 Error BinaryStreamWriter::writeStreamRef(BinaryStreamRef Ref) { 41 return writeStreamRef(Ref, Ref.getLength()); 42 } 43 44 Error BinaryStreamWriter::writeStreamRef(BinaryStreamRef Ref, uint32_t Length) { 45 BinaryStreamReader SrcReader(Ref.slice(0, Length)); 46 // This is a bit tricky. If we just call readBytes, we are requiring that it 47 // return us the entire stream as a contiguous buffer. There is no guarantee 48 // this can be satisfied by returning a reference straight from the buffer, as 49 // an implementation may not store all data in a single contiguous buffer. So 50 // we iterate over each contiguous chunk, writing each one in succession. 51 while (SrcReader.bytesRemaining() > 0) { 52 ArrayRef<uint8_t> Chunk; 53 if (auto EC = SrcReader.readLongestContiguousChunk(Chunk)) 54 return EC; 55 if (auto EC = writeBytes(Chunk)) 56 return EC; 57 } 58 return Error::success(); 59 } 60