Replace auto_delete* with defer

src/h2load_http2_session.cc

@@ -106,8 +106,8 @@ void Http2Session::on_connect()
 
   nghttp2_session_callbacks_new(&callbacks);
 
-  util::auto_delete<nghttp2_session_callbacks*> callbacks_deleter
-    (callbacks, nghttp2_session_callbacks_del);
+  auto callbacks_deleter =
+    util::defer(callbacks, nghttp2_session_callbacks_del);
 
   nghttp2_session_callbacks_set_on_frame_recv_callback
     (callbacks, on_frame_recv_callback);

src/nghttp.cc

@@ -1832,8 +1832,7 @@ int run(char **uris, int n)
   nghttp2_session_callbacks *callbacks;
 
   nghttp2_session_callbacks_new(&callbacks);
-  util::auto_delete<nghttp2_session_callbacks*> cbsdel
-    (callbacks, nghttp2_session_callbacks_del);
+  auto cbsdel = util::defer(callbacks, nghttp2_session_callbacks_del);
 
   nghttp2_session_callbacks_set_on_stream_close_callback
     (callbacks, on_stream_close_callback);

src/shrpx_http2_session.cc

@@ -1377,8 +1377,8 @@ int Http2Session::on_connect()
     return -1;
   }
 
-  util::auto_delete<nghttp2_session_callbacks*> callbacks_deleter
-    (callbacks, nghttp2_session_callbacks_del);
+  auto callbacks_deleter =
+    util::defer(callbacks, nghttp2_session_callbacks_del);
 
   nghttp2_session_callbacks_set_on_stream_close_callback
     (callbacks, on_stream_close_callback);

src/shrpx_http2_upstream.cc

@@ -637,8 +637,8 @@ Http2Upstream::Http2Upstream(ClientHandler *handler)
 
   assert(rv == 0);
 
-  util::auto_delete<nghttp2_session_callbacks*> callbacks_deleter
-    (callbacks, nghttp2_session_callbacks_del);
+  auto callbacks_deleter =
+    util::defer(callbacks, nghttp2_session_callbacks_del);
 
   nghttp2_session_callbacks_set_on_stream_close_callback
     (callbacks, on_stream_close_callback);

src/shrpx_ssl.cc

@@ -602,8 +602,7 @@ void get_altnames(X509 *cert,
     static_cast<GENERAL_NAMES*>
     (X509_get_ext_d2i(cert, NID_subject_alt_name, nullptr, nullptr));
   if(altnames) {
-    util::auto_delete<GENERAL_NAMES*> altnames_deleter(altnames,
-                                                       GENERAL_NAMES_free);
+    auto altnames_deleter = util::defer(altnames, GENERAL_NAMES_free);
     size_t n = sk_GENERAL_NAME_num(altnames);
     for(size_t i = 0; i < n; ++i) {
       const GENERAL_NAME *altname = sk_GENERAL_NAME_value(altnames, i);
@@ -665,7 +664,7 @@ int check_cert(SSL *ssl)
     LOG(ERROR) << "No certificate found";
     return -1;
   }
-  util::auto_delete<X509*> cert_deleter(cert, X509_free);
+  auto cert_deleter = util::defer(cert, X509_free);
   long verify_res = SSL_get_verify_result(ssl);
   if(verify_res != X509_V_OK) {
     LOG(ERROR) << "Certificate verification failed: "
@@ -864,7 +863,7 @@ int cert_lookup_tree_add_cert_from_file(CertLookupTree *lt, SSL_CTX *ssl_ctx,
     LOG(ERROR) << "BIO_new failed";
     return -1;
   }
-  util::auto_delete<BIO*> bio_deleter(bio, BIO_vfree);
+  auto bio_deleter = util::defer(bio, BIO_vfree);
   if(!BIO_read_filename(bio, certfile)) {
     LOG(ERROR) << "Could not read certificate file '" << certfile << "'";
     return -1;
@@ -875,7 +874,7 @@ int cert_lookup_tree_add_cert_from_file(CertLookupTree *lt, SSL_CTX *ssl_ctx,
                << certfile << "'";
     return -1;
   }
-  util::auto_delete<X509*> cert_deleter(cert, X509_free);
+  auto cert_deleter = util::defer(cert, X509_free);
   std::string common_name;
   std::vector<std::string> dns_names;
   std::vector<std::string> ip_addrs;

src/util.h

@@ -51,46 +51,26 @@ constexpr size_t array_size(T (&)[N])
   return N;
 }
 
-template<typename T>
-class auto_delete {
-private:
-  T obj_;
-  void (*deleter_)(T);
-public:
-  auto_delete(T obj, void (*deleter)(T)):obj_(obj), deleter_(deleter) {}
+template<typename T, typename F>
+struct Defer {
+  Defer(T t, F f)
+    : t(t), f(std::move(f))
+  {}
 
-  ~auto_delete()
+  ~Defer()
   {
-    deleter_(obj_);
+    f(t);
   }
+
+  T t;
+  F f;
 };
 
-template<typename T>
-class auto_delete_d {
-private:
-  T obj_;
-public:
-  auto_delete_d(T obj):obj_(obj) {}
-
-  ~auto_delete_d()
-  {
-    delete obj_;
-  }
-};
-
-template<typename T, typename R>
-class auto_delete_r {
-private:
-  T obj_;
-  R (*deleter_)(T);
-public:
-  auto_delete_r(T obj, R (*deleter)(T)):obj_(obj), deleter_(deleter) {}
-
-  ~auto_delete_r()
-  {
-    (void)deleter_(obj_);
-  }
-};
+template<typename T, typename F>
+Defer<T, F> defer(T&& t, F f)
+{
+  return Defer<T, F>(std::forward<T>(t), std::forward<F>(f));
+}
 
 extern const char DEFAULT_STRIP_CHARSET[];