UWP平台Taglib编译（2）

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#endif  // _WIN32
}class FileStream::FileStreamPrivate
{
public:FileStreamPrivate(const FileName &fileName): file(InvalidFileHandle), name(fileName), readOnly(true){}FileHandle file;FileNameHandle name;bool readOnly;
};// public membersFileStream::FileStream(FileName fileName, bool openReadOnly): d(new FileStreamPrivate(fileName))
{// First try with read / write mode, if that fails, fall back to read only.if(!openReadOnly)d->file = openFile(fileName, false);if(d->file != InvalidFileHandle)d->readOnly = false;elsed->file = openFile(fileName, true);if(d->file == InvalidFileHandle){
# ifdef _WIN32debug("Could not open file " + fileName.toString());
# elsedebug("Could not open file " + String(static_cast(d->name)));
# endif}
}FileStream::~FileStream()
{if(isOpen())closeFile(d->file);delete d;
}FileName FileStream::name() const
{return d->name;
}ByteVector FileStream::readBlock(ulong length)
{if(!isOpen()) {debug("FileStream::readBlock() -- invalid file.");return ByteVector::null;}if(length == 0)return ByteVector::null;const ulong streamLength = static_cast(FileStream::length());if(length > bufferSize() && length > streamLength)length = streamLength;ByteVector buffer(static_cast(length));const size_t count = readFile(d->file, buffer);buffer.resize(static_cast(count));return buffer;
}void FileStream::writeBlock(const ByteVector &data)
{if(!isOpen()) {debug("FileStream::writeBlock() -- invalid file.");return;}if(readOnly()) {debug("FileStream::writeBlock() -- read only file.");return;}writeFile(d->file, data);
}void FileStream::insert(const ByteVector &data, ulong start, ulong replace)
{if(!isOpen()) {debug("FileStream::insert() -- invalid file.");return;}if(readOnly()) {debug("FileStream::insert() -- read only file.");return;}if(data.size() == replace) {seek(start);writeBlock(data);return;}else if(data.size() < replace) {seek(start);writeBlock(data);removeBlock(start + data.size(), replace - data.size());return;}// Woohoo!  Faster (about 20%) than id3lib at last.  I had to get hardcore// and avoid TagLib's high level API for rendering just copying parts of// the file that don't contain tag data.//// Now I'll explain the steps in this ugliness:// First, make sure that we're working with a buffer that is longer than// the *differnce* in the tag sizes.  We want to avoid overwriting parts// that aren't yet in memory, so this is necessary.ulong bufferLength = bufferSize();while(data.size() - replace > bufferLength)bufferLength += bufferSize();// Set where to start the reading and writing.long readPosition = start + replace;long writePosition = start;ByteVector buffer = data;ByteVector aboutToOverwrite(static_cast(bufferLength));while(true){// Seek to the current read position and read the data that we're about// to overwrite.  Appropriately increment the readPosition.seek(readPosition);const size_t bytesRead = readFile(d->file, aboutToOverwrite);aboutToOverwrite.resize(bytesRead);readPosition += bufferLength;// Check to see if we just read the last block.  We need to call clear()// if we did so that the last write succeeds.if(bytesRead < bufferLength)clear();// Seek to the write position and write our buffer.  Increment the// writePosition.seek(writePosition);writeBlock(buffer);// We hit the end of the file.if(bytesRead == 0)break;writePosition += buffer.size();// Make the current buffer the data that we read in the beginning.buffer = aboutToOverwrite;}
}void FileStream::removeBlock(ulong start, ulong length)
{if(!isOpen()) {debug("FileStream::removeBlock() -- invalid file.");return;}ulong bufferLength = bufferSize();long readPosition = start + length;long writePosition = start;ByteVector buffer(static_cast(bufferLength));for(size_t bytesRead = -1; bytesRead != 0;){seek(readPosition);bytesRead = readFile(d->file, buffer);readPosition += bytesRead;// Check to see if we just read the last block.  We need to call clear()// if we did so that the last write succeeds.if(bytesRead < buffer.size()) {clear();buffer.resize(bytesRead);}seek(writePosition);writeFile(d->file, buffer);writePosition += bytesRead;}truncate(writePosition);
}bool FileStream::readOnly() const
{return d->readOnly;
}bool FileStream::isOpen() const
{return (d->file != InvalidFileHandle);
}void FileStream::seek(long offset, Position p)
{if(!isOpen()) {debug("FileStream::seek() -- invalid file.");return;}#ifdef _WIN32DWORD whence;switch(p) {case Beginning:whence = FILE_BEGIN;break;case Current:whence = FILE_CURRENT;break;case End:whence = FILE_END;break;default:debug("FileStream::seek() -- Invalid Position value.");return;}#if WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_APP | WINAPI_PARTITION_SYSTEM)LARGE_INTEGER distance = { 0 };distance.QuadPart = offset;if (!SetFilePointerEx(d->file, distance, NULL, whence))
#elseSetLastError(NO_ERROR);SetFilePointer(d->file, offset, NULL, whence);const int lastError = GetLastError();if(lastError != NO_ERROR && lastError != ERROR_NEGATIVE_SEEK)
#endifdebug("FileStream::seek() -- Failed to set the file pointer.");#elseint whence;switch(p) {case Beginning:whence = SEEK_SET;break;case Current:whence = SEEK_CUR;break;case End:whence = SEEK_END;break;default:debug("FileStream::seek() -- Invalid Position value.");return;}fseek(d->file, offset, whence);#endif
}void FileStream::clear()
{
#ifdef _WIN32// NOP#elseclearerr(d->file);#endif
}long FileStream::tell() const
{
#ifdef _WIN32#if WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_APP | WINAPI_PARTITION_SYSTEM)LARGE_INTEGER distance = { 0 };LARGE_INTEGER position = { 0 };if (SetFilePointerEx(d->file, distance, &position, FILE_CURRENT)) {return static_cast(position.QuadPart);}
#elseSetLastError(NO_ERROR);const DWORD position = SetFilePointer(d->file, 0, NULL, FILE_CURRENT);if(GetLastError() == NO_ERROR) {return static_cast(position);}
#endifelse {debug("FileStream::tell() -- Failed to get the file pointer.");return 0;}#elsereturn ftell(d->file);#endif
}long FileStream::length()
{if(!isOpen()) {debug("FileStream::length() -- invalid file.");return 0;}#ifdef _WIN32#if WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_APP | WINAPI_PARTITION_SYSTEM)LARGE_INTEGER fileSize = { 0 };if (GetFileSizeEx(d->file, &fileSize)) {return static_cast(fileSize.QuadPart);}
#elseSetLastError(NO_ERROR);const DWORD fileSize = GetFileSize(d->file, NULL);if (GetLastError() == NO_ERROR) {return static_cast(fileSize);}
#endifelse {debug("FileStream::length() -- Failed to get the file size.");return 0;}#elseconst long curpos = tell();seek(0, End);const long endpos = tell();seek(curpos, Beginning);return endpos;#endif
}// protected membersvoid FileStream::truncate(long length)
{
#ifdef _WIN32const long currentPos = tell();seek(length);SetLastError(NO_ERROR);SetEndOfFile(d->file);if(GetLastError() != NO_ERROR) {debug("FileStream::truncate() -- Failed to truncate the file.");}seek(currentPos);#elseconst int error = ftruncate(fileno(d->file), length);if(error != 0) {debug("FileStream::truncate() -- Coundn't truncate the file.");}#endif
}TagLib::uint FileStream::bufferSize()
{return 1024;
}

为了便于调试，还需要修改taglib\toolkit\tdebuglistener.cpp，以便在调试直接在Output窗口输出调试信息，完整代码如下：

/***************************************************************************copyright            : (C) 2013 by Tsuda Kageyuemail                : tsuda.kageyu@gmail.com***************************************************************************//****************************************************************************   This library is free software; you can redistribute it and/or modify  **   it under the terms of the GNU Lesser General Public License version   **   2.1 as published by the Free Software Foundation.                     **                                                                         **   This library is distributed in the hope that it will be useful, but   **   WITHOUT ANY WARRANTY; without even the implied warranty of            **   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU     **   Lesser General Public License for more details.                       **                                                                         **   You should have received a copy of the GNU Lesser General Public      **   License along with this library; if not, write to the Free Software   **   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA         **   02110-1301  USA                                                       **                                                                         **   Alternatively, this file is available under the Mozilla Public        **   License Version 1.1.  You may obtain a copy of the License at         **   http://www.mozilla.org/MPL/                                           ****************************************************************************/#include "tdebuglistener.h"#include
#include #ifdef _WIN32
# include
#endifusing namespace TagLib;namespace
{class DefaultListener : public DebugListener{public:virtual void printMessage(const String &msg){
#ifdef _WIN32const wstring wstr = msg.toWString();
#if WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_APP | WINAPI_PARTITION_SYSTEM)OutputDebugStringW(wstr.c_str());
#elseconst int len = WideCharToMultiByte(CP_ACP, 0, wstr.c_str(), -1, NULL, 0, NULL, NULL);if(len != 0) {std::vector buf(len);WideCharToMultiByte(CP_ACP, 0, wstr.c_str(), -1, &buf[0], len, NULL, NULL);std::cerr << std::string(&buf[0]);}
#endif#elsestd::cerr << msg;#endif }};DefaultListener defaultListener;
}namespace TagLib
{DebugListener *debugListener = &defaultListener;DebugListener::DebugListener(){}DebugListener::~DebugListener(){}void setDebugListener(DebugListener *listener){if(listener)debugListener = listener;elsedebugListener = &defaultListener;}
}

最后，编译吧，骚年！！！

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