Squashed 'third_party/boostorg/multi_index/' content from commit d95a949
Change-Id: Ie67c2d797c11dc122c7f11e767e81691bf2191a4
git-subtree-dir: third_party/boostorg/multi_index
git-subtree-split: d95a94942b918140e565feb99ed36ea97c30084e
diff --git a/example/ip_allocator.cpp b/example/ip_allocator.cpp
new file mode 100644
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+++ b/example/ip_allocator.cpp
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+/* Boost.MultiIndex example of use of Boost.Interprocess allocators.
+ *
+ * Copyright 2003-2008 Joaquin M Lopez Munoz.
+ * Distributed under the Boost Software License, Version 1.0.
+ * (See accompanying file LICENSE_1_0.txt or copy at
+ * http://www.boost.org/LICENSE_1_0.txt)
+ *
+ * See http://www.boost.org/libs/multi_index for library home page.
+ */
+
+#if !defined(NDEBUG)
+#define BOOST_MULTI_INDEX_ENABLE_INVARIANT_CHECKING
+#define BOOST_MULTI_INDEX_ENABLE_SAFE_MODE
+#endif
+
+#include <boost/config.hpp> /* keep it first to prevent nasty warns in MSVC */
+#include <algorithm>
+#include <boost/interprocess/allocators/allocator.hpp>
+#include <boost/interprocess/containers/string.hpp>
+#include <boost/interprocess/managed_mapped_file.hpp>
+#include <boost/interprocess/sync/named_mutex.hpp>
+#include <boost/interprocess/sync/scoped_lock.hpp>
+#include <boost/multi_index_container.hpp>
+#include <boost/multi_index/ordered_index.hpp>
+#include <boost/multi_index/member.hpp>
+#include <iostream>
+#include <iterator>
+#include <sstream>
+#include <string>
+
+using boost::multi_index_container;
+using namespace boost::multi_index;
+namespace bip=boost::interprocess;
+
+/* shared_string is a string type placeable in shared memory,
+ * courtesy of Boost.Interprocess.
+ */
+
+typedef bip::basic_string<
+ char,std::char_traits<char>,
+ bip::allocator<char,bip::managed_mapped_file::segment_manager>
+> shared_string;
+
+/* Book record. All its members can be placed in shared memory,
+ * hence the structure itself can too.
+ */
+
+struct book
+{
+ shared_string name;
+ shared_string author;
+ unsigned pages;
+ unsigned prize;
+
+ book(const shared_string::allocator_type& al):
+ name(al),author(al),pages(0),prize(0)
+ {}
+
+ friend std::ostream& operator<<(std::ostream& os,const book& b)
+ {
+ os<<b.author<<": \""<<b.name<<"\", $"<<b.prize<<", "<<b.pages<<" pages\n";
+ return os;
+ }
+};
+
+/* partial_str_less allows for partial searches taking into account
+ * only the first n chars of the strings compared against. See
+ * Tutorial: Basics: Special lookup operations for more info on this
+ * type of comparison functors.
+ */
+
+/* partial_string is a mere string holder used to differentiate from
+ * a plain string.
+ */
+
+struct partial_string
+{
+ partial_string(const shared_string& str):str(str){}
+ shared_string str;
+};
+
+struct partial_str_less
+{
+ bool operator()(const shared_string& x,const shared_string& y)const
+ {
+ return x<y;
+ }
+
+ bool operator()(const shared_string& x,const partial_string& y)const
+ {
+ return x.substr(0,y.str.size())<y.str;
+ }
+
+ bool operator()(const partial_string& x,const shared_string& y)const
+ {
+ return x.str<y.substr(0,x.str.size());
+ }
+};
+
+/* Define a multi_index_container of book records with indices on
+ * author, name and prize. The index on names allows for partial
+ * searches. This container can be placed in shared memory because:
+ * * book can be placed in shared memory.
+ * * We are using a Boost.Interprocess specific allocator.
+ */
+
+/* see Compiler specifics: Use of member_offset for info on
+ * BOOST_MULTI_INDEX_MEMBER
+ */
+
+typedef multi_index_container<
+ book,
+ indexed_by<
+ ordered_non_unique<
+ BOOST_MULTI_INDEX_MEMBER(book,shared_string,author)
+ >,
+ ordered_non_unique<
+ BOOST_MULTI_INDEX_MEMBER(book,shared_string,name),
+ partial_str_less
+ >,
+ ordered_non_unique<
+ BOOST_MULTI_INDEX_MEMBER(book,unsigned,prize)
+ >
+ >,
+ bip::allocator<book,bip::managed_mapped_file::segment_manager>
+> book_container;
+
+/* A small utility to get data entered via std::cin */
+
+template<typename T>
+void enter(const char* msg,T& t)
+{
+ std::cout<<msg;
+ std::string str;
+ std::getline(std::cin,str);
+ std::istringstream iss(str);
+ iss>>t;
+}
+
+void enter(const char* msg,std::string& str)
+{
+ std::cout<<msg;
+ std::getline(std::cin,str);
+}
+
+void enter(const char* msg,shared_string& str)
+{
+ std::cout<<msg;
+ std::string stdstr;
+ std::getline(std::cin,stdstr);
+ str=stdstr.c_str();
+}
+
+int main()
+{
+ /* Create (or open) the memory mapped file where the book container
+ * is stored, along with a mutex for synchronized access.
+ */
+
+ bip::managed_mapped_file seg(
+ bip::open_or_create,"./book_container.db",
+ 65536);
+ bip::named_mutex mutex(
+ bip::open_or_create,"7FD6D7E8-320B-11DC-82CF-F0B655D89593");
+
+ /* create or open the book container in shared memory */
+
+ book_container* pbc=seg.find_or_construct<book_container>("book container")(
+ book_container::ctor_args_list(),
+ book_container::allocator_type(seg.get_segment_manager()));
+
+ std::string command_info=
+ "1. list books by author\n"
+ "2. list all books by prize\n"
+ "3. insert a book\n"
+ "4. delete a book\n"
+ "0. exit\n";
+
+ std::cout<<command_info;
+
+ /* main loop */
+
+ for(bool exit=false;!exit;){
+ int command=-1;
+ enter("command: ",command);
+
+ switch(command){
+ case 0:{ /* exit */
+ exit=true;
+ break;
+ }
+ case 1:{ /* list books by author */
+ std::string author;
+ enter("author (empty=all authors): ",author);
+
+ /* operations with the container must be mutex protected */
+
+ bip::scoped_lock<bip::named_mutex> lock(mutex);
+
+ std::pair<book_container::iterator,book_container::iterator> rng;
+ if(author.empty()){
+ rng=std::make_pair(pbc->begin(),pbc->end());
+ }
+ else{
+ rng=pbc->equal_range(
+ shared_string(
+ author.c_str(),
+ shared_string::allocator_type(seg.get_segment_manager())));
+ }
+
+ if(rng.first==rng.second){
+ std::cout<<"no entries\n";
+ }
+ else{
+ std::copy(
+ rng.first,rng.second,std::ostream_iterator<book>(std::cout));
+ }
+ break;
+ }
+ case 2:{ /* list all books by prize */
+ bip::scoped_lock<bip::named_mutex> lock(mutex);
+
+ std::copy(
+ get<2>(*pbc).begin(),get<2>(*pbc).end(),
+ std::ostream_iterator<book>(std::cout));
+ break;
+ }
+ case 3:{ /* insert a book */
+ book b(shared_string::allocator_type(seg.get_segment_manager()));
+
+ enter("author: ",b.author);
+ enter("name: " ,b.name);
+ enter("prize: " ,b.prize);
+ enter("pages: " ,b.pages);
+
+ std::cout<<"insert the following?\n"<<b<<"(y/n): ";
+ char yn='n';
+ enter("",yn);
+ if(yn=='y'||yn=='Y'){
+ bip::scoped_lock<bip::named_mutex> lock(mutex);
+ pbc->insert(b);
+ }
+
+ break;
+ }
+ case 4:{ /* delete a book */
+ shared_string name(
+ shared_string::allocator_type(seg.get_segment_manager()));
+ enter(
+ "name of the book (you can enter\nonly the first few characters): ",
+ name);
+
+ typedef nth_index<book_container,1>::type index_by_name;
+ index_by_name& idx=get<1>(*pbc);
+ index_by_name::iterator it;
+ book b(shared_string::allocator_type(seg.get_segment_manager()));
+
+ {
+ /* Look for a book whose title begins with name. Note that we
+ * are unlocking after doing the search so as to not leave the
+ * container blocked during user prompting. That is also why a
+ * local copy of the book is done.
+ */
+
+ bip::scoped_lock<bip::named_mutex> lock(mutex);
+
+ it=idx.find(partial_string(name));
+ if(it==idx.end()){
+ std::cout<<"no such book found\n";
+ break;
+ }
+ b=*it;
+ }
+
+ std::cout<<"delete the following?\n"<<b<<"(y/n): ";
+ char yn='n';
+ enter("",yn);
+ if(yn=='y'||yn=='Y'){
+ bip::scoped_lock<bip::named_mutex> lock(mutex);
+ idx.erase(it);
+ }
+
+ break;
+ }
+ default:{
+ std::cout<<"select one option:\n"<<command_info;
+ break;
+ }
+ }
+ }
+
+ return 0;
+}