1 /* 2 * Generic accessor functionality. 3 * 4 * Copyright (C) 2021 Paul Boddie <paul@boddie.org.uk> 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License as 8 * published by the Free Software Foundation; either version 2 of 9 * the License, or (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, 19 * Boston, MA 02110-1301, USA 20 */ 21 22 #pragma once 23 24 #include <mem/flexpage.h> 25 26 27 28 /* A file accessor, providing flexpages corresponding to file regions. */ 29 30 class Accessor 31 { 32 protected: 33 bool _closed = false; 34 offset_t _size; 35 36 /* Data transfer helper methods. */ 37 38 virtual void fill_populated(Flexpage *flexpage); 39 40 virtual void flush_populated(Flexpage *flexpage); 41 42 public: 43 fileid_t fileid; 44 45 explicit Accessor(fileid_t fileid); 46 47 virtual ~Accessor(); 48 49 virtual offset_t get_size() = 0; 50 51 virtual void set_size(offset_t size) = 0; 52 53 virtual void close(); 54 55 /* Data transfer methods. */ 56 57 virtual void fill(Flexpage *flexpage); 58 59 virtual void flush(Flexpage *flexpage); 60 61 /* Lifecycle methods. */ 62 63 virtual void remove(); 64 }; 65 66 // vim: tabstop=4 expandtab shiftwidth=4