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/*
* Copyright (C) 2010 Google Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following disclaimer
* in the documentation and/or other materials provided with the
* distribution.
* * Neither the name of Google Inc. nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "config.h"
#include "FileStream.h"
#include "FileSystem.h"
#include <wtf/text/WTFString.h>
namespace WebCore {
FileStream::FileStream()
: m_handle(invalidPlatformFileHandle)
, m_bytesProcessed(0)
, m_totalBytesToRead(0)
{
}
FileStream::~FileStream()
{
close();
}
long long FileStream::getSize(const String& path, double expectedModificationTime)
{
// Check the modification time for the possible file change.
time_t modificationTime;
if (!getFileModificationTime(path, modificationTime))
return -1;
if (isValidFileTime(expectedModificationTime)) {
if (static_cast<time_t>(expectedModificationTime) != modificationTime)
return -1;
}
// Now get the file size.
long long length;
if (!getFileSize(path, length))
return -1;
return length;
}
bool FileStream::openForRead(const String& path, long long offset, long long length)
{
if (isHandleValid(m_handle))
return true;
// Open the file.
m_handle = openFile(path, OpenForRead);
if (!isHandleValid(m_handle))
return false;
// Jump to the beginning position if the file has been sliced.
if (offset > 0) {
if (seekFile(m_handle, offset, SeekFromBeginning) < 0)
return false;
}
m_totalBytesToRead = length;
m_bytesProcessed = 0;
return true;
}
void FileStream::close()
{
if (isHandleValid(m_handle)) {
closeFile(m_handle);
m_handle = invalidPlatformFileHandle;
}
}
int FileStream::read(char* buffer, int bufferSize)
{
if (!isHandleValid(m_handle))
return -1;
long long remaining = m_totalBytesToRead - m_bytesProcessed;
int bytesToRead = (remaining < bufferSize) ? static_cast<int>(remaining) : bufferSize;
int bytesRead = 0;
if (bytesToRead > 0)
bytesRead = readFromFile(m_handle, buffer, bytesToRead);
if (bytesRead < 0)
return -1;
if (bytesRead > 0)
m_bytesProcessed += bytesRead;
return bytesRead;
}
} // namespace WebCore
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