src/support/events.h

   1 // Copyright (c) 2016 The Bitcoin Core developers
   2 // Distributed under the MIT software license, see the accompanying
   3 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
   4
   5 #ifndef BITCOIN_SUPPORT_EVENTS_H
   6 #define BITCOIN_SUPPORT_EVENTS_H
   7
   8 #include <ios>
   9 #include <memory>
  10
  11 #include <event2/event.h>
  12 #include <event2/http.h>
  13
  14 #define MAKE_RAII(type) \
  15 /* deleter */\
  16 struct type##_deleter {\
  17     void operator()(struct type* ob) {\
  18         type##_free(ob);\
  19     }\
  20 };\
  21 /* unique ptr typedef */\
  22 typedef std::unique_ptr<struct type, type##_deleter> raii_##type
  23
  24 MAKE_RAII(event_base);
  25 MAKE_RAII(event);
  26 MAKE_RAII(evhttp);
  27 MAKE_RAII(evhttp_request);
  28 MAKE_RAII(evhttp_connection);
  29
  30 inline raii_event_base obtain_event_base() {
  31     auto result = raii_event_base(event_base_new());
  32     if (!result.get())
  33         throw std::runtime_error("cannot create event_base");
  34     return result;
  35 }
  36
  37 inline raii_event obtain_event(struct event_base* base, evutil_socket_t s, short events, event_callback_fn cb, void* arg) {
  38     return raii_event(event_new(base, s, events, cb, arg));
  39 }
  40
  41 inline raii_evhttp obtain_evhttp(struct event_base* base) {
  42     return raii_evhttp(evhttp_new(base));
  43 }
  44
  45 inline raii_evhttp_request obtain_evhttp_request(void(*cb)(struct evhttp_request *, void *), void *arg) {
  46     return raii_evhttp_request(evhttp_request_new(cb, arg));
  47 }
  48
  49 inline raii_evhttp_connection obtain_evhttp_connection_base(struct event_base* base, std::string host, uint16_t port) {
  50     auto result = raii_evhttp_connection(evhttp_connection_base_new(base, nullptr, host.c_str(), port));
  51     if (!result.get())
  52         throw std::runtime_error("create connection failed");
  53     return result;
  54 }
  55
  56 #endif // BITCOIN_SUPPORT_EVENTS_H