BitMagic-C++
sample6.cpp
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1 /*
2 Copyright(c) 2002-2017 Anatoliy Kuznetsov(anatoliy_kuznetsov at yahoo.com)
3 
4 Licensed under the Apache License, Version 2.0 (the "License");
5 you may not use this file except in compliance with the License.
6 You may obtain a copy of the License at
7 
8  http://www.apache.org/licenses/LICENSE-2.0
9 
10 Unless required by applicable law or agreed to in writing, software
11 distributed under the License is distributed on an "AS IS" BASIS,
12 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 See the License for the specific language governing permissions and
14 limitations under the License.
15 
16 For more information please visit: http://bitmagic.io
17 */
18 
19 /** \example sample6.cpp
20  This example demonstrates using of custom memory allocators.
21  In this case allocator works as a memory checker, counts number of
22  allocations and deallocations to make sure that there is no memory leaks.
23 */
24 /*! \file sample6.cpp
25  \brief Example: bvector<> custom memory allocator
26 */
27 #include <iostream>
28 #include <cassert>
29 #include "bm.h"
30 
31 using namespace std;
32 
33 
34 // Custom allocator keeps number of all alloc/free calls.
35 // It also reservs the front word of the allocated block and saves
36 // number of elements allocated. On deallocation it makes sure
37 // it deallocates the same size as allocated
38 //
39 // Please note, that this sample allocator is NOT compatible with SIMD
40 // optimizations, requiring special address alignment
41 //
42 
44 {
45 public:
46 static unsigned na_;
47 static unsigned nf_;
48 
49  static bm::word_t* allocate(size_t n, const void *)
50  {
51  ++na_;
52  assert(n);
53  bm::word_t* p =
54  (bm::word_t*) ::malloc((n+1) * sizeof(bm::word_t));
55  *p = (unsigned)n;
56  return ++p;
57  }
58 
59  static void deallocate(bm::word_t* p, size_t /* n */)
60  {
61  ++nf_;
62  --p;
63  ::free(p);
64  }
65 
66  static int balance()
67  {
68  return int(nf_ - na_);
69  }
70 };
71 
72 unsigned dbg_block_allocator::na_ = 0;
73 unsigned dbg_block_allocator::nf_ = 0;
74 
76 {
77 public:
78 static unsigned na_;
79 static unsigned nf_;
80 
81  static void* allocate(size_t n, const void *)
82  {
83  ++na_;
84  assert(sizeof(size_t) == sizeof(void*));
85  void* p = ::malloc((n+1) * sizeof(void*));
86  size_t* s = (size_t*) p;
87  *s = n;
88  return (void*)++s;
89  }
90 
91  static void deallocate(void* p, size_t /* n */)
92  {
93  ++nf_;
94  size_t* s = (size_t*) p;
95  --s;
96  ::free(s);
97  }
98 
99  static int balance()
100  {
101  return int(nf_ - na_);
102  }
103 
104 };
105 
106 unsigned dbg_ptr_allocator::na_ = 0;
107 unsigned dbg_ptr_allocator::nf_ = 0;
108 
109 
110 typedef
113 
115 
116 int main(void)
117 {
118  try
119  {
120  {
121  bvect bv;
122 
123  bv[10] = true;
124  bv[100000] = true;
125  bv[10000000] = false;
126  }
127 
128  cout << "Number of BLOCK allocations = " << dbg_block_allocator::na_ << endl;
129  cout << "Number of PTR allocations = " << dbg_ptr_allocator::na_ << endl;
130  }
131  catch(std::exception& ex)
132  {
133  std::cerr << ex.what() << std::endl;
134  return 1;
135  }
136 
137  assert(dbg_block_allocator::balance() == 0);
138  assert(dbg_ptr_allocator::balance() == 0);
139 
140  return 0;
141 }
142 
143 
dbg_block_allocator::balance
static int balance()
Definition: sample6.cpp:66
dbg_ptr_allocator::allocate
static void * allocate(size_t n, const void *)
Definition: sample6.cpp:81
dbg_ptr_allocator
Definition: sample6.cpp:75
bm::alloc_pool
Allocation pool object.
Definition: bmalloc.h:200
dbg_block_allocator::allocate
static bm::word_t * allocate(size_t n, const void *)
Definition: sample6.cpp:49
dbg_ptr_allocator::na_
static unsigned na_
Definition: sample6.cpp:78
dbg_ptr_allocator::deallocate
static void deallocate(void *p, size_t)
Definition: sample6.cpp:91
bm::bvector
Bitvector Bit-vector container with runtime compression of bits.
Definition: bm.h:107
dbg_block_allocator::nf_
static unsigned nf_
Definition: sample6.cpp:47
dbg_ptr_allocator::balance
static int balance()
Definition: sample6.cpp:99
dbg_block_allocator::deallocate
static void deallocate(bm::word_t *p, size_t)
Definition: sample6.cpp:59
dbg_ptr_allocator::nf_
static unsigned nf_
Definition: sample6.cpp:79
dbg_block_allocator
Definition: sample6.cpp:43
main
int main(void)
Definition: sample6.cpp:116
bm::word_t
unsigned int word_t
Definition: bmconst.h:38
dbg_block_allocator::na_
static unsigned na_
Definition: sample6.cpp:46
bvect
bm::bvector< dbg_alloc > bvect
Definition: sample6.cpp:114
bm.h
Compressed bit-vector bvector<> container, set algebraic methods, traversal iterators.
dbg_alloc
bm::mem_alloc< dbg_block_allocator, dbg_ptr_allocator, bm::alloc_pool< dbg_block_allocator, dbg_ptr_allocator > > dbg_alloc
Definition: sample6.cpp:112
bm::mem_alloc
BM style allocator adapter.
Definition: bmalloc.h:254