dll/example/tutorial5/load_all.cpp
2019-01-06 20:30:18 +03:00

147 lines
4.2 KiB
C++

// Copyright 2014 Renato Tegon Forti, Antony Polukhin.
// Copyright 2015-2019 Antony Polukhin.
//
// 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)
// MinGW related workaround
#define BOOST_DLL_FORCE_ALIAS_INSTANTIATION
#include "../b2_workarounds.hpp"
#include "../tutorial4/static_plugin.hpp"
#include <boost/dll/runtime_symbol_info.hpp> // for program_location()
#include <boost/dll/shared_library.hpp>
#include <boost/make_shared.hpp>
#include <boost/container/map.hpp>
#include <boost/filesystem.hpp>
#include <iostream>
//[plugcpp_plugins_collector_def
namespace dll = boost::dll;
class plugins_collector {
// Name => plugin
typedef boost::container::map<std::string, dll::shared_library> plugins_t;
boost::dll::fs::path plugins_directory_;
plugins_t plugins_;
// loads all plugins in plugins_directory_
void load_all();
// Gets `my_plugin_api` instance using "create_plugin" or "plugin" imports,
// stores plugin with its name in the `plugins_` map.
void insert_plugin(BOOST_RV_REF(dll::shared_library) lib);
public:
plugins_collector(const boost::dll::fs::path& plugins_directory)
: plugins_directory_(plugins_directory)
{
load_all();
}
void print_plugins() const;
std::size_t count() const;
// ...
};
//]
//[plugcpp_plugins_collector_load_all
void plugins_collector::load_all() {
namespace fs = ::boost::dll::fs;
typedef fs::path::string_type string_type;
const string_type extension = dll::shared_library::suffix().native();
// Searching a folder for files with '.so' or '.dll' extension
fs::recursive_directory_iterator endit;
for (fs::recursive_directory_iterator it(plugins_directory_); it != endit; ++it) {
if (!fs::is_regular_file(*it)) {
continue;
}
/*<-*/
if ( !b2_workarounds::is_shared_library((*it).path()) ) {
continue;
}
/*->*/
// We found a file. Trying to load it
boost::dll::fs::error_code error;
dll::shared_library plugin(it->path(), error);
if (error) {
continue;
}
std::cout << "Loaded (" << plugin.native() << "):" << it->path() << '\n';
// Gets plugin using "create_plugin" or "plugin" function
insert_plugin(boost::move(plugin));
}
dll::shared_library plugin(dll::program_location());
std::cout << "Loaded self\n";
insert_plugin(boost::move(plugin));
}
//]
//[plugcpp_plugins_collector_insert_plugin
void plugins_collector::insert_plugin(BOOST_RV_REF(dll::shared_library) lib) {
std::string plugin_name;
if (lib.has("create_plugin")) {
plugin_name = lib.get_alias<boost::shared_ptr<my_plugin_api>()>("create_plugin")()->name();
} else if (lib.has("plugin")) {
plugin_name = lib.get<my_plugin_api>("plugin").name();
} else {
return;
}
if (plugins_.find(plugin_name) == plugins_.cend()) {
plugins_[plugin_name] = boost::move(lib);
}
}
//]
void plugins_collector::print_plugins() const {
plugins_t::const_iterator const end = plugins_.cend();
for (plugins_t::const_iterator it = plugins_.cbegin(); it != end; ++it) {
std::cout << '(' << it->second.native() << "): " << it->first << '\n';
}
}
std::size_t plugins_collector::count() const {
return plugins_.size();
}
//[plugcpp_load_all
int main(int argc, char* argv[]) {
/*<-*/
BOOST_ASSERT(argc >= 3);
boost::dll::fs::path path1(argv[1]);
for (int i = 2; i < argc; ++i) {
boost::dll::fs::path path2(argv[i]);
boost::dll::fs::path res;
for (boost::dll::fs::path::iterator it1 = path1.begin(), it2 = path2.begin();
it1 != path1.end() && it2 != path2.end() && *it1 == *it2;
++it1, ++it2)
{
res /= *it1;
}
path1 = res;
}
std::string new_argv = path1.string();
std::cout << "\nPlugins path: " << new_argv << ":\n";
argv[1] = &new_argv[0];
/*->*/
plugins_collector plugins(argv[1]);
std::cout << "\n\nUnique plugins " << plugins.count() << ":\n";
plugins.print_plugins();
// ...
//]
BOOST_ASSERT(plugins.count() >= 3);
}