added dns cache

repertory/librepertory/include/comm/curl/curl_comm.hpp

@@ -23,6 +23,7 @@
 #define REPERTORY_INCLUDE_COMM_CURL_CURL_COMM_HPP_
 
 #include "app_config.hpp"
+#include "comm/curl/dns_cache.hpp"
 #include "comm/curl/multi_request.hpp"
 #include "comm/i_http_comm.hpp"
 #include "events/event_system.hpp"
@@ -210,6 +211,8 @@ public:
         curl_easy_setopt(curl, CURLOPT_HTTPHEADER, header_list);
       }
 
+      dns_cache::set_cache(curl);
+
       auto url = construct_url(curl, request.get_path(), cfg) + parameters;
       curl_easy_setopt(curl, CURLOPT_URL, url.c_str());
 

repertory/librepertory/include/comm/curl/dns_cache.hpp

@@ -0,0 +1,66 @@
+/*
+  Copyright <2018-2025> <scott.e.graves@protonmail.com>
+
+  Permission is hereby granted, free of charge, to any person obtaining a copy
+  of this software and associated documentation files (the "Software"), to deal
+  in the Software without restriction, including without limitation the rights
+  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+  copies of the Software, and to permit persons to whom the Software is
+  furnished to do so, subject to the following conditions:
+
+  The above copyright notice and this permission notice shall be included in all
+  copies or substantial portions of the Software.
+
+  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+  SOFTWARE.
+*/
+#ifndef REPERTORY_INCLUDE_COMM_CURL_DNS_CACHE_HPP_
+#define REPERTORY_INCLUDE_COMM_CURL_DNS_CACHE_HPP_
+
+namespace repertory {
+class dns_cache final {
+private:
+  struct curl_sh_deleter final {
+    void operator()(CURLSH *ptr) {
+      if (ptr != nullptr) {
+        curl_share_cleanup(ptr);
+      }
+    }
+  };
+
+  using curl_sh_t = std::unique_ptr<CURLSH, curl_sh_deleter>;
+
+public:
+  dns_cache() = delete;
+  dns_cache(const dns_cache &) = delete;
+  dns_cache(dns_cache &&) = delete;
+  ~dns_cache() = delete;
+
+  auto operator=(const dns_cache &) -> dns_cache & = delete;
+  auto operator=(dns_cache &&) -> dns_cache & = delete;
+
+private:
+  static curl_sh_t cache_;
+  static std::unique_ptr<unique_recur_mutex_lock> lock_;
+  static std::recursive_mutex mtx_;
+
+private:
+  static auto create_cache() -> CURLSH *;
+
+  static void lock_callback(CURL * /* curl */, curl_lock_data /* data */,
+                            curl_lock_access /* access */, void * /* ptr */);
+
+  static void unlock_callback(CURL * /* curl */, curl_lock_data /* data */,
+                              curl_lock_access /* access */, void * /* ptr */);
+
+public:
+  static void set_cache(CURL *curl);
+};
+} // namespace repertory
+
+#endif // REPERTORY_INCLUDE_COMM_CURL_DNS_CACHE_HPP_

repertory/librepertory/src/comm/curl/dns_cache.cpp

@@ -0,0 +1,60 @@
+/*
+  Copyright <2018-2025> <scott.e.graves@protonmail.com>
+
+  Permission is hereby granted, free of charge, to any person obtaining a copy
+  of this software and associated documentation files (the "Software"), to deal
+  in the Software without restriction, including without limitation the rights
+  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+  copies of the Software, and to permit persons to whom the Software is
+  furnished to do so, subject to the following conditions:
+
+  The above copyright notice and this permission notice shall be included in all
+  copies or substantial portions of the Software.
+
+  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+  SOFTWARE.
+*/
+#include "comm/curl/dns_cache.hpp"
+
+namespace repertory {
+dns_cache::curl_sh_t dns_cache::cache_{dns_cache::create_cache()};
+
+std::unique_ptr<unique_recur_mutex_lock> dns_cache::lock_;
+
+std::recursive_mutex dns_cache::mtx_;
+
+auto dns_cache::create_cache() -> CURLSH * {
+  auto *ret = curl_share_init();
+  if (ret == nullptr) {
+    return ret;
+  }
+
+  lock_ = std::make_unique<unique_recur_mutex_lock>(mtx_);
+
+  curl_share_setopt(ret, CURLSHOPT_SHARE, CURL_LOCK_DATA_DNS);
+  curl_share_setopt(ret, CURLSHOPT_LOCKFUNC, lock_callback);
+  curl_share_setopt(ret, CURLSHOPT_UNLOCKFUNC, unlock_callback);
+
+  return ret;
+}
+
+void dns_cache::lock_callback(CURL * /* curl */, curl_lock_data /* data */,
+                              curl_lock_access /* access */, void * /* ptr */) {
+  lock_->lock();
+}
+
+void dns_cache::set_cache(CURL *curl) {
+  curl_easy_setopt(curl, CURLOPT_SHARE, cache_.get());
+}
+
+void dns_cache::unlock_callback(CURL * /* curl */, curl_lock_data /* data */,
+                                curl_lock_access /* access */,
+                                void * /* ptr */) {
+  lock_->unlock();
+}
+} // namespace repertory