shared_header.cc

简单的动态内存管理程序源代码

// file: test/shared_header.cc
// author: Marc Bumble
// Mon Aug 11, 2003
// Memory allocator code for shared memory access
// Copyright (C) 2003 by Marc D. Bumble

//  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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.



#include <shared_memory.h>
#include <allocator_bit_vector.h>
#include <fstream>  // for std::ofstream to()

char  key_val1[] = "/allocate_key";
// char key_val2[] = "/tmp/.allocate_key2";

int main(int argc, char **argv) {

  int passed=0, failed=0;
  enum {
    num_of_pages = 1000,
    page_size = 8*1024,
    bit_vector_size = 1000/8 + 1
  };


  // First, make sure that the shared memory segment are not in use
  // during the test.
  // shm_unlink(key_val1);

// create memory for the shared memory header
  // simulate the page sizes
  int buff_size = num_of_pages*page_size +
    sizeof(mem_space::shared_memory_header_t) +
    bit_vector_size;
  unsigned char buffer[buff_size]; 
  mem_space::shared_memory_header_t* smh =
    new(buffer)mem_space::shared_memory_header_t(1000,
						 8*1024,
						 key_val1,
						 (int) buffer,
						 buff_size,
 						 0); // proj_id
// 						 key_val1,

  std::cerr << "----------------------------------------" << std::endl;
  std::cerr << "Shared memory header test. " << std::endl;
  smh->mark_pages(0,5);
  std::cerr << "\tMarking pages 0 through 4" << std::endl;
  int start_page = smh->find_free_pages(4);
  std::cerr << "\tFinding 4 free pages" << std::endl;
  if (start_page==5)
    passed++;
  else
    failed++;
  smh->clear_pages(2,3);
  std::cerr << "\tClearing pages 2 through 4" << std::endl;
  start_page = smh->find_free_pages(3);
  std::cerr << "\tFind 3 free pages" << std::endl;
  if (start_page==2)
    passed++;
  else
    failed++;
  smh->mark_pages(0,num_of_pages-3);
  std::cerr << "\tMarking pages 0 through " << num_of_pages-3 << std::endl;
  start_page = smh->find_free_pages(3);
  std::cerr << "\tFinding 3 free pages" << std::endl;
  if (start_page==num_of_pages-3)
    passed++;
  else
    failed++;
  std::cerr << "\tTesting page offset." << std::endl;
  int page_offset = smh->get_page_offset(1);
  if (page_offset ==
      static_cast<int>(sizeof(mem_space::shared_memory_header_t) +
		       smh->get_bit_vec_size() + 1*page_size))
    passed++;
  else
    failed++;
  std::cerr << "\tTesting page offset." << std::endl;
  page_offset = smh->get_page_offset(num_of_pages-1);
  if (page_offset ==
      static_cast<int>(sizeof(mem_space::shared_memory_header_t) +
		       smh->get_bit_vec_size() +
		       (num_of_pages-1)*page_size))
    passed++;
  else
    failed++;
  smh->set_key("/key_name_is_not_path");
  char key_name[512];
  smh->get_key(key_name);
  std::cerr << "\tPath name test: " << key_name << std::endl;
  // Destruct the shared memory head which was constructed with new above
  // Cleans up the semaphores
  smh->~shared_memory_header_t();
  std::cerr << "Passed: " << passed << std::endl;
  std::cerr << "Failed: " << failed << std::endl;
  std::cerr << "----------------------------------------" << std::endl;
  
  
  return 0;
}