1 /*********************************************************************/ 2 // dar - disk archive - a backup/restoration program 3 // Copyright (C) 2002-2052 Denis Corbin 4 // 5 // This program is free software; you can redistribute it and/or 6 // modify it under the terms of the GNU General Public License 7 // as published by the Free Software Foundation; either version 2 8 // of the License, or (at your option) any later version. 9 // 10 // This program is distributed in the hope that it will be useful, 11 // but WITHOUT ANY WARRANTY; without even the implied warranty of 12 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 // GNU General Public License for more details. 14 // 15 // You should have received a copy of the GNU General Public License 16 // along with this program; if not, write to the Free Software 17 // Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. 18 // 19 // to contact the author : http://dar.linux.free.fr/email.html 20 /*********************************************************************/ 21 22 /// \file generic_thread.hpp 23 /// \brief class generic_thread provides a way to interact with a generic_file ran in an other thread 24 /// \ingroup Private 25 /// 26 27 28 #ifndef GENERIC_THREAD_HPP 29 #define GENERIC_THREAD_HPP 30 31 #include "../my_config.h" 32 33 #include "generic_file.hpp" 34 #include "messaging.hpp" 35 #include "slave_thread.hpp" 36 #include "erreurs.hpp" 37 38 namespace libdar 39 { 40 41 42 class generic_thread : public generic_file 43 { 44 public: 45 // default values for constuctor 46 static const unsigned int tampon_block_size = 102401; 47 static const unsigned int tampon_num_block = 1000; 48 static const unsigned int tampon_block_size_ctrl = 1024; 49 static const unsigned int tampon_num_block_ctrl = 10; 50 51 /// constructor 52 /// 53 /// \param[in] ptr is the generic_file that will be read from/written to by a separated thread 54 /// \param[in] block_size is the size of block used to pass information to and from the remote thread 55 /// \param[in] num_block maximum number of blocks that can be sent without being retrieved by the other threads 56 /// \note that the pointed to generic_file must exist during the whole life of the generic_thread. Its memory 57 /// management after the generic_thread has died is under the responsibility of the caller of the generic_thread 58 generic_thread(generic_file *ptr, 59 U_I data_block_size = tampon_block_size, 60 U_I data_num_block = tampon_num_block, 61 U_I ctrl_block_size = tampon_block_size_ctrl, 62 U_I ctrl_num_block = tampon_num_block_ctrl); 63 generic_thread(const generic_thread & ref); //< copy constructor is disabled (throws exception) operator =(const generic_thread & ref)64 const generic_thread & operator = (const generic_thread & ref) { throw SRC_BUG; }; 65 virtual ~generic_thread(); 66 67 // inherited methods from generic_file 68 69 virtual bool skippable(skippability direction, const infinint & amount); 70 virtual bool skip(const infinint & pos); 71 virtual bool skip_to_eof(); 72 virtual bool skip_relative(S_I x); 73 virtual infinint get_position() const; 74 75 protected: 76 // inherited from generic_file 77 virtual void inherited_read_ahead(const infinint & amount); 78 virtual U_I inherited_read(char *a, U_I size); 79 virtual void inherited_write(const char *a, U_I size); 80 81 /// generic_file inherited method to sync all pending writes 82 /// 83 /// \note no data in transit in this object so we should not do anything, 84 /// however for performance propagating the order to slave_thread 85 virtual void inherited_sync_write(); 86 virtual void inherited_flush_read(); 87 virtual void inherited_terminate(); 88 89 90 private: 91 libthreadar::fast_tampon<char> toslave_data; 92 libthreadar::fast_tampon<char> tomaster_data; 93 libthreadar::fast_tampon<char> toslave_ctrl; 94 libthreadar::fast_tampon<char> tomaster_ctrl; 95 slave_thread *remote; 96 bool reached_eof; //< whether we reached end of file 97 char data_header; //< contains 1 byte header for data 98 char data_header_eof; //< contains 1 byte header for data + eof 99 bool running; //< whether a remote is expected to run, tid is then set 100 pthread_t tid; //< thread id of remote 101 102 // the following variables are locally used in quite all methods 103 // they do not contain valuable information outside each method call 104 messaging_encode order; 105 messaging_decode answer; 106 unsigned int num; 107 char *ptr; 108 label dataname; 109 110 void send_order(); 111 void read_answer(); //< \note ptr must be released/recycled after this call 112 void check_answer(msg_type expected); 113 void wake_up_slave_if_asked(); //< check whether an order to wakeup the slave has been received, and send wake up the slave release_block_answer()114 void release_block_answer() { tomaster_ctrl.fetch_recycle(ptr); ptr = nullptr; }; 115 void release_data_ptr(); 116 void purge_data_pipe(); //< drops all data in the toslave_data pipe 117 void my_run(); 118 void my_join(); 119 }; 120 121 } // end of namespace 122 123 #endif 124