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Diffstat (limited to 'libktorrent/util/mmapfile.h')
-rw-r--r-- | libktorrent/util/mmapfile.h | 146 |
1 files changed, 146 insertions, 0 deletions
diff --git a/libktorrent/util/mmapfile.h b/libktorrent/util/mmapfile.h new file mode 100644 index 0000000..ca0d782 --- /dev/null +++ b/libktorrent/util/mmapfile.h @@ -0,0 +1,146 @@ +/*************************************************************************** + * Copyright (C) 2005 by Joris Guisson * + * joris.guisson@gmail.com * + * * + * This program is free software; you can redistribute it and/or modify * + * it under the terms of the GNU General Public License as published by * + * the Free Software Foundation; either version 2 of the License, or * + * (at your option) any later version. * + * * + * This program 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 General Public License for more details. * + * * + * You should have received a copy of the GNU General Public License * + * along with this program; if not, write to the * + * Free Software Foundation, Inc., * + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. * + ***************************************************************************/ +#ifndef BTMMAPFILE_H +#define BTMMAPFILE_H + + +#include <qstring.h> +#include <util/constants.h> + +namespace bt +{ + + /** + * @author Joris Guisson + * @brief Memory mapped file + * + * This class allows to access memory mapped files. It's pretty similar to + * File. + * TODO: make sure large files work (not really needed for the blocklist) + */ + class MMapFile + { + public: + MMapFile(); + virtual ~MMapFile(); + + enum Mode + { + READ,WRITE, RW + }; + /** + * Open the file. If mode is write and the file doesn't exist, it will + * be created. + * @param file Filename + * @param mode Mode (READ, WRITE or RW) + * @return true upon succes + */ + bool open(const QString & file,Mode mode); + + /** + * Open the file. If mode is write and the file doesn't exist, it will + * be created. + * @param file Filename + * @param mode Mode (READ, WRITE or RW) + * @param size Size of the memory mapping (the file will be enlarged to this value) + * @return true upon succes + */ + bool open(const QString & file,Mode mode,Uint64 size); + + /** + * Close the file. Undoes the memory mapping. + */ + void close(); + + /** + * Flush the file. + */ + void flush(); + + /** + * Write a bunch of data. + * @param buf The data + * @param size Size of the data + * @return The number of bytes written + */ + Uint32 write(const void* buf,Uint32 size); + + /** + * Read a bunch of data + * @param buf The buffer to store the data + * @param size Size of the buffer + * @return The number of bytes read + */ + Uint32 read(void* buf,Uint32 size); + + enum SeekPos + { + BEGIN, + END, + CURRENT + }; + + /** + * Seek in the file. + * @param from Position to seek from + * @param num Number of bytes to move + * @return New position + */ + Uint64 seek(SeekPos from,Int64 num); + + /// Check to see if we are at the end of the file. + bool eof() const; + + /// Get the current position in the file. + Uint64 tell() const; + + /// Get the error string. + QString errorString() const; + + /// Get the file size + Uint64 getSize() const; + + + /** + * Get a pointer to the mmapped region of data. + * @param off Offset into buffer, if invalid 0 will be returned + * @return Pointer to a location in the mmapped region + */ + Uint8* getData(Uint64 off); + + /// Gets the data pointer + void* getDataPointer() { return data; } + private: + void growFile(Uint64 new_size); + + private: + int fd; + Uint8* data; + Uint64 size; // size of mmapping + Uint64 file_size; // size of file + Uint64 ptr; + QString filename; + Mode mode; + }; + +} + + +#endif |