Revert "Added a function to add callbacks that are called when a logger is registered (#2883)"

This reverts commit b6eeb7364c, since it causes deadlocks too easily for the users.

include/spdlog/details/registry-inl.h

@@ -259,22 +259,6 @@ SPDLOG_INLINE void registry::register_logger_(std::shared_ptr<logger> new_logger
     auto logger_name = new_logger->name();
     throw_if_exists_(logger_name);
     loggers_[logger_name] = std::move(new_logger);
-
-    const auto& logger = loggers_[logger_name];
-    for (const auto& on_registration_callback : on_registration_callbacks_) {
-        on_registration_callback(logger);
-    }
-}
-
-SPDLOG_INLINE void registry::add_on_registration_callback(
-    const std::function<void(std::shared_ptr<logger>)>& callback) {
-    std::lock_guard<std::mutex> lock(logger_map_mutex_);
-    on_registration_callbacks_.push_back(callback);
-}
-
-SPDLOG_INLINE void registry::drop_all_on_registration_callbacks() {
-    std::lock_guard<std::mutex> lock(logger_map_mutex_);
-    on_registration_callbacks_.clear();
 }
 
 }  // namespace details

include/spdlog/details/registry.h

@@ -17,7 +17,6 @@
 #include <mutex>
 #include <string>
 #include <unordered_map>
-#include <vector>
 
 namespace spdlog {
 class logger;
@@ -93,10 +92,6 @@ public:
 
     void apply_logger_env_levels(std::shared_ptr<logger> new_logger);
 
-    void add_on_registration_callback(const std::function<void(std::shared_ptr<logger>)>& callback);
-
-    void drop_all_on_registration_callbacks();
-
 private:
     registry();
     ~registry();
@@ -117,7 +112,6 @@ private:
     std::shared_ptr<logger> default_logger_;
     bool automatic_registration_ = true;
     size_t backtrace_n_messages_ = 0;
-    std::vector<std::function<void(std::shared_ptr<logger>)>> on_registration_callbacks_;
 };
 
 }  // namespace details

include/spdlog/spdlog-inl.h

@@ -89,12 +89,4 @@ SPDLOG_INLINE void apply_logger_env_levels(std::shared_ptr<logger> logger) {
     details::registry::instance().apply_logger_env_levels(std::move(logger));
 }
 
-SPDLOG_INLINE void add_on_registration_callback(const std::function<void(const std::shared_ptr<logger>&)>& callback) {
-    details::registry::instance().add_on_registration_callback(callback);
-}
-
-SPDLOG_INLINE void drop_all_on_registration_callbacks() {
-    details::registry::instance().drop_all_on_registration_callbacks();
-}
-
 }  // namespace spdlog

include/spdlog/spdlog.h

@@ -140,21 +140,6 @@ SPDLOG_API void set_default_logger(std::shared_ptr<spdlog::logger> default_logge
 //   spdlog::apply_logger_env_levels(mylogger);
 SPDLOG_API void apply_logger_env_levels(std::shared_ptr<logger> logger);
 
-// Add a callback that is called whenever a logger is registered
-//
-// Useful for intercepting loggers that are dynamically created during the application's lifetime
-// (e.g. from dynamically loaded libraries, etc.)
-// Example:
-// void my_on_registration_callback(const std::shared_ptr<spdlog::logger>& logger) {
-//     logger->do_stuff();
-// }
-// ...
-// spdlog::add_on_registration_callback(my_on_registration_callback);
-SPDLOG_API void add_on_registration_callback(const std::function<void(const std::shared_ptr<logger>&)>& callback);
-
-// Clear all callbacks that were added to intercept registrations (see "add_on_registration_callback")
-SPDLOG_API void drop_all_on_registration_callbacks();
-
 template <typename... Args>
 inline void log(source_loc source,
                 level::level_enum lvl,

tests/test_registry.cpp

@@ -110,30 +110,3 @@ TEST_CASE("disable automatic registration", "[registry]") {
     spdlog::set_level(spdlog::level::info);
     spdlog::set_automatic_registration(true);
 }
-
-TEST_CASE("add_on_registration_callback", "[registry]") {
-    std::vector<std::string> registered_logger_names;
-    auto on_registration_callback = [&](std::shared_ptr<spdlog::logger> logger)
-    {
-        registered_logger_names.push_back(logger->name());
-    };
-    spdlog::add_on_registration_callback(on_registration_callback);
-
-    auto captured_registration_logger1 = spdlog::create<spdlog::sinks::stdout_color_sink_mt>("captured_registration_logger1");
-
-    spdlog::set_automatic_registration(false);
-    auto non_captured_registration_logger1 = spdlog::create<spdlog::sinks::stdout_color_sink_mt>("non_captured_registration_logger1");
-
-    auto captured_registration_logger2 = spdlog::create<spdlog::sinks::stdout_color_sink_mt>("captured_registration_logger2");
-    spdlog::register_logger(captured_registration_logger2);
-
-    spdlog::drop_all_on_registration_callbacks();
-    auto non_captured_registration_logger2 = spdlog::create<spdlog::sinks::stdout_color_sink_mt>("non_captured_registration_logger2");
-    spdlog::register_logger(non_captured_registration_logger2);
-
-    // Check that only the automatically registered logged and the manually registered logger were captured
-    REQUIRE(registered_logger_names == std::vector<std::string>({"captured_registration_logger1", "captured_registration_logger2"}));
-
-    spdlog::set_level(spdlog::level::info);
-    spdlog::set_automatic_registration(true);
-}