1//////////////////////////////////////////////////////////////////////////////
2//
3// (C) Copyright Ion Gaztanaga 2006-2012. Distributed under the Boost
4// Software License, Version 1.0. (See accompanying file
5// LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
6//
7// See http://www.boost.org/libs/interprocess for documentation.
8//
9//////////////////////////////////////////////////////////////////////////////
10
11#include <boost/interprocess/detail/workaround.hpp>
12//[doc_bufferstream
13#include <boost/interprocess/managed_shared_memory.hpp>
14#include <boost/interprocess/streams/bufferstream.hpp>
15#include <vector>
16#include <iterator>
17#include <cstddef>
18//<-
19#include "../test/get_process_id_name.hpp"
20//->
21
22using namespace boost::interprocess;
23
24int main ()
25{
26 //Remove shared memory on construction and destruction
27 struct shm_remove
28 {
29 //<-
30 #if 1
31 shm_remove() { shared_memory_object::remove(filename: test::get_process_id_name()); }
32 ~shm_remove(){ shared_memory_object::remove(filename: test::get_process_id_name()); }
33 #else
34 //->
35 shm_remove() { shared_memory_object::remove("MySharedMemory"); }
36 ~shm_remove(){ shared_memory_object::remove("MySharedMemory"); }
37 //<-
38 #endif
39 //->
40 } remover;
41 //<-
42 (void)remover;
43 //->
44
45 //Create shared memory
46 //<-
47 #if 1
48 managed_shared_memory segment(create_only,test::get_process_id_name(), 65536);
49 #else
50 //->
51 managed_shared_memory segment(create_only,
52 "MySharedMemory", //segment name
53 65536);
54 //<-
55 #endif
56 //->
57
58 //Fill data
59 std::vector<int> data;
60 data.reserve(n: 100);
61 for(std::size_t i = 0; i < 100; ++i){
62 data.push_back(x: (int)i);
63 }
64 const std::size_t BufferSize = 100*5;
65
66 //Allocate a buffer in shared memory to write data
67 char *my_cstring =
68 segment.construct<char>(name: "MyCString")[BufferSize]('\0');
69 bufferstream mybufstream(my_cstring, BufferSize);
70
71 //Now write data to the buffer
72 for(std::size_t i = 0; i < 100; ++i){
73 mybufstream << data[i] << std::endl;
74 }
75
76 //Check there was no overflow attempt
77 assert(mybufstream.good());
78
79 //Extract all values from the shared memory string
80 //directly to a vector.
81 std::vector<int> data2;
82 std::istream_iterator<int> it(mybufstream), itend;
83 std::copy(first: it, last: itend, result: std::back_inserter(x&: data2));
84
85 //This extraction should have ended will fail error since
86 //the numbers formatted in the buffer end before the end
87 //of the buffer. (Otherwise it would trigger eofbit)
88 assert(mybufstream.fail());
89
90 //Compare data
91 assert(std::equal(data.begin(), data.end(), data2.begin()));
92
93 //Clear errors and rewind
94 mybufstream.clear();
95 mybufstream.seekp(0, std::ios::beg);
96
97 //Now write again the data trying to do a buffer overflow
98 for(std::size_t i = 0, m = data.size()*5; i < m; ++i){
99 mybufstream << data[i%5u] << std::endl;
100 }
101
102 //Now make sure badbit is active
103 //which means overflow attempt.
104 assert(!mybufstream.good());
105 assert(mybufstream.bad());
106 segment.destroy_ptr(ptr: my_cstring);
107 return 0;
108}
109//]
110
111

source code of boost/libs/interprocess/example/doc_bufferstream.cpp