Fix compile error with libstdc++ and/or --disable-threads

src/shrpx.cc

@@ -438,7 +438,11 @@ void refresh_cb(struct ev_loop *loop, ev_timer *w, int revents) {
 
 namespace {
 void renew_ticket_key_cb(struct ev_loop *loop, ev_timer *w, int revents) {
-  auto old_ticket_keys = std::atomic_load(&get_config()->ticket_keys);
+#ifndef NOTHREADS
+  std::lock_guard<std::mutex> g(mod_config()->ticket_keys_lock);
+#endif // !NOTHREADS
+  auto old_ticket_keys = get_config()->ticket_keys;
+
   auto ticket_keys = std::make_shared<TicketKeys>();
   if (LOG_ENABLED(INFO)) {
     LOG(INFO) << "renew ticket key";
@@ -461,8 +465,7 @@ void renew_ticket_key_cb(struct ev_loop *loop, ev_timer *w, int revents) {
     if (LOG_ENABLED(INFO)) {
       LOG(INFO) << "failed to renew ticket key";
     }
-    std::atomic_store(&mod_config()->ticket_keys,
+    mod_config()->ticket_keys.reset();
-                      std::shared_ptr<TicketKeys>());
     return;
   }
 
@@ -473,7 +476,7 @@ void renew_ticket_key_cb(struct ev_loop *loop, ev_timer *w, int revents) {
     }
   }
 
-  std::atomic_store(&mod_config()->ticket_keys, ticket_keys);
+  mod_config()->ticket_keys = ticket_keys;
 }
 } // namespace
 

src/shrpx_config.h

@@ -36,6 +36,7 @@
 #include <vector>
 #include <memory>
 #include <atomic>
+#include <mutex>
 
 #include <openssl/ssl.h>
 
@@ -183,6 +184,7 @@ struct Config {
   std::vector<LogFragment> accesslog_format;
   std::vector<DownstreamAddr> downstream_addrs;
   std::vector<std::string> tls_ticket_key_files;
+  std::mutex ticket_keys_lock;
   std::shared_ptr<TicketKeys> ticket_keys;
   // binary form of http proxy host and port
   sockaddr_union downstream_http_proxy_addr;

src/shrpx_ssl.cc

@@ -147,9 +147,18 @@ namespace {
 int ticket_key_cb(SSL *ssl, unsigned char *key_name, unsigned char *iv,
                   EVP_CIPHER_CTX *ctx, HMAC_CTX *hctx, int enc) {
   auto handler = static_cast<ClientHandler *>(SSL_get_app_data(ssl));
-  auto ticket_keys = get_config()->auto_tls_ticket_key
+#ifndef NOTHREADS
-                         ? std::atomic_load(&get_config()->ticket_keys)
+  std::shared_ptr<TicketKeys> ticket_keys;
-                         : get_config()->ticket_keys;
+  if (get_config()->auto_tls_ticket_key) {
+    std::lock_guard<std::mutex> g(mod_config()->ticket_keys_lock);
+    ticket_keys = get_config()->ticket_keys;
+  } else {
+    ticket_keys = get_config()->ticket_keys;
+  }
+#else  // NOTHREADS
+  auto ticket_keys = get_config()->ticket_keys;
+#endif // NOTHREADS
+
   if (!ticket_keys) {
     /* No ticket keys available.  Perform full handshake */
     return 0;

src/shrpx_worker.cc

@@ -66,7 +66,9 @@ Worker::~Worker() {
 }
 
 void Worker::run() {
+#ifndef NOTHREADS
   fut_ = std::async(std::launch::async, [this] { this->run_loop(); });
+#endif // !NOTHREADS
 }
 
 void Worker::run_loop() {
@@ -74,7 +76,11 @@ void Worker::run_loop() {
   ev_run(loop_);
 }
 
-void Worker::wait() { fut_.get(); }
+void Worker::wait() {
+#ifndef NOTHREADS
+  fut_.get();
+#endif // !NOTHREADS
+}
 
 void Worker::send(const WorkerEvent &event) {
   {