refactor: add std::unique_ptr<evhttp> handler to utils-ev (#4261)

libtransmission/rpc-server.cc

@@ -716,7 +716,7 @@ static void startServer(tr_rpc_server* server)
     else
     {
         evhttp_set_gencb(httpd, handle_request, server);
-        server->httpd = std::unique_ptr<evhttp, void (*)(evhttp*)>{ httpd, &evhttp_free };
+        server->httpd.reset(httpd);
 
         tr_logAddInfo(fmt::format(_("Listening for RPC and Web requests on '{address}'"), fmt::arg("address", addr_port_str)));
     }

libtransmission/rpc-server.h

@@ -17,6 +17,7 @@
 #include "transmission.h"
 
 #include "net.h"
+#include "utils-ev.h"
 
 struct evhttp;
 struct tr_variant;
@@ -155,8 +156,7 @@ public:
     std::unique_ptr<struct tr_rpc_address> bind_address_;
 
     std::unique_ptr<libtransmission::Timer> start_retry_timer;
-    std::unique_ptr<struct evhttp, void (*)(struct evhttp*)> httpd{ nullptr, [](evhttp*) {
-                                                                   } };
+    libtransmission::evhelpers::evhttp_unique_ptr httpd;
     tr_session* const session;
 
     size_t login_attempts_ = 0U;

libtransmission/session.h

@@ -21,9 +21,11 @@
 #include <string>
 #include <string_view>
 #include <tuple>
-#include <utility> // std::pair
+#include <utility> // for std::pair
 #include <vector>
 
+#include <event2/util.h> // for evutil_socket_t
+
 #include "transmission.h"
 
 #include "announce-list.h"

libtransmission/tr-lpd.cc

@@ -18,6 +18,7 @@
 #include <netinet/in.h> /* sockaddr_in */
 #endif
 
+#include <event2/event.h>
 #include <event2/util.h>
 
 #include <fmt/format.h>

libtransmission/utils-ev.h

@@ -11,8 +11,19 @@
 
 #include <memory>
 
-#include <event2/buffer.h>
-#include <event2/event.h>
+extern "C"
+{
+    struct evbuffer;
+    struct event;
+    struct event_base;
+    struct evhttp;
+
+    void evbuffer_free(struct evbuffer*);
+    void event_base_free(struct event_base*);
+    int event_del(struct event*);
+    void event_free(struct event*);
+    void evhttp_free(struct evhttp*);
+}
 
 namespace libtransmission::evhelpers
 {
@@ -57,4 +68,17 @@ struct EventDeleter
 
 using event_unique_ptr = std::unique_ptr<struct event, EventDeleter>;
 
+struct EvhttpDeleter
+{
+    void operator()(struct evhttp* evh) const noexcept
+    {
+        if (evh != nullptr)
+        {
+            evhttp_free(evh);
+        }
+    }
+};
+
+using evhttp_unique_ptr = std::unique_ptr<struct evhttp, EvhttpDeleter>;
+
 } // namespace libtransmission::evhelpers