1 /* 2 * A pipe pager providing access to pipe content and navigation support. 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 <fsserver/pipe_accessor.h> 25 #include <fsserver/pipe_object_interface.h> 26 #include <fsserver/pipe_paging.h> 27 #include <fsserver/pager.h> 28 29 30 31 /* A pager abstraction for a pipe. */ 32 33 class PipePager : public Pager, public PipeObject 34 { 35 protected: 36 PipePaging *_paging; 37 bool _writing; 38 39 /* Helper methods. */ 40 41 virtual long next_region_for_reader(offset_t *populated_size, offset_t *size); 42 43 virtual long next_region_for_writer(offset_t *populated_size, offset_t *size); 44 45 virtual long pipe_error(); 46 47 public: 48 explicit PipePager(PipePaging *paging, bool writer); 49 50 virtual void close(); 51 52 /* Server details. */ 53 54 int expected_items(); 55 56 ipc_server_handler_type handler(); 57 58 void *interface() 59 { return static_cast<PipeObject *>(this); } 60 61 /* Pager methods. */ 62 63 virtual long map(offset_t offset, address_t hot_spot, flags_t flags, l4_snd_fpage_t *region); 64 65 /* Pipe methods. */ 66 67 virtual long current_region(offset_t *populated_size, offset_t *size); 68 69 virtual long next_region(offset_t *populated_size, offset_t *size); 70 }; 71 72 // vim: tabstop=4 expandtab shiftwidth=4