1 /* 2 * Copyright (C) 2014 Google Inc. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions are 6 * met: 7 * 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above 11 * copyright notice, this list of conditions and the following disclaimer 12 * in the documentation and/or other materials provided with the 13 * distribution. 14 * * Neither the name of Google Inc. nor the names of its 15 * contributors may be used to endorse or promote products derived from 16 * this software without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31 #include "config.h" 32 #include "core/xml/parser/SharedBufferReader.h" 33 34 #include "platform/SharedBuffer.h" 35 #include "wtf/PassRefPtr.h" 36 #include "wtf/RefPtr.h" 37 38 #include <algorithm> 39 #include <cstring> 40 41 namespace blink { 42 43 SharedBufferReader::SharedBufferReader(PassRefPtr<SharedBuffer> buffer) 44 : m_buffer(buffer) 45 , m_currentOffset(0) 46 { 47 } 48 49 SharedBufferReader::~SharedBufferReader() 50 { 51 } 52 53 int SharedBufferReader::readData(char* outputBuffer, unsigned askedToRead) 54 { 55 if (!m_buffer || m_currentOffset > m_buffer->size()) 56 return 0; 57 58 unsigned bytesCopied = 0; 59 unsigned bytesLeft = m_buffer->size() - m_currentOffset; 60 unsigned lenToCopy = std::min(askedToRead, bytesLeft); 61 62 while (bytesCopied < lenToCopy) { 63 const char* data; 64 unsigned segmentSize = m_buffer->getSomeData(data, m_currentOffset); 65 if (!segmentSize) 66 break; 67 68 segmentSize = std::min(segmentSize, lenToCopy - bytesCopied); 69 memcpy(outputBuffer + bytesCopied, data, segmentSize); 70 bytesCopied += segmentSize; 71 m_currentOffset += segmentSize; 72 } 73 74 return bytesCopied; 75 } 76 77 } // namespace blink 78