include/libtorrent/file_pool.hpp

   1 /*
   2
   3 Copyright (c) 2006, Arvid Norberg
   4 All rights reserved.
   5
   6 Redistribution and use in source and binary forms, with or without
   7 modification, are permitted provided that the following conditions
   8 are met:
   9
  10     * Redistributions of source code must retain the above copyright
  11       notice, this list of conditions and the following disclaimer.
  12     * Redistributions in binary form must reproduce the above copyright
  13       notice, this list of conditions and the following disclaimer in
  14       the documentation and/or other materials provided with the distribution.
  15     * Neither the name of the author nor the names of its
  16       contributors may be used to endorse or promote products derived
  17       from this software without specific prior written permission.
  18
  19 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  20 AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22 ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
  23 LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  24 CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  25 SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  26 INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  27 CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  28 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  29 POSSIBILITY OF SUCH DAMAGE.
  30
  31 */
  32
  33 #ifndef TORRENT_FILE_POOL_HPP
  34 #define TORRENT_FILE_POOL_HPP
  35
  36 #ifdef _MSC_VER
  37 #pragma warning(push, 1)
  38 #endif
  39
  40 #include <boost/filesystem/path.hpp>
  41 #include <boost/multi_index_container.hpp>
  42 #include <boost/multi_index/member.hpp>
  43 #include <boost/multi_index/ordered_index.hpp>
  44 #include <boost/shared_ptr.hpp>
  45 #include <boost/thread.hpp>
  46
  47 #ifdef _MSC_VER
  48 #pragma warning(pop)
  49 #endif
  50
  51 #include "libtorrent/file.hpp"
  52 #include "libtorrent/time.hpp"
  53
  54 namespace libtorrent
  55 {
  56
  57         using boost::multi_index::multi_index_container;
  58         using boost::multi_index::ordered_non_unique;
  59         using boost::multi_index::ordered_unique;
  60         using boost::multi_index::indexed_by;
  61         using boost::multi_index::member;
  62         namespace fs = boost::filesystem;
  63
  64         struct TORRENT_EXPORT file_pool : boost::noncopyable
  65         {
  66                 file_pool(int size = 40): m_size(size) {}
  67
  68                 boost::shared_ptr<file> open_file(void* st, fs::path const& p
  69                         , file::open_mode m, error_code& ec);
  70                 void release(void* st);
  71                 void release(fs::path const& p);
  72                 void resize(int size);
  73
  74         private:
  75                 int m_size;
  76
  77                 struct lru_file_entry
  78                 {
  79                         lru_file_entry(): last_use(time_now()) {}
  80                         mutable boost::shared_ptr<file> file_ptr;
  81                         fs::path file_path;
  82                         void* key;
  83                         ptime last_use;
  84                         file::open_mode mode;
  85                 };
  86
  87                 typedef multi_index_container<
  88                         lru_file_entry, indexed_by<
  89                                 ordered_unique<member<lru_file_entry, fs::path
  90                                         , &lru_file_entry::file_path> >
  91                                 , ordered_non_unique<member<lru_file_entry, ptime
  92                                         , &lru_file_entry::last_use> >
  93                                 , ordered_non_unique<member<lru_file_entry, void*
  94                                         , &lru_file_entry::key> >
  95                                 >
  96                         > file_set;
  97
  98                 file_set m_files;
  99                 boost::mutex m_mutex;
 100         };
 101 }
 102
 103 #endif