file_event_handlers add before_open function

example/example.cpp

@@ -121,7 +121,11 @@ void rotating_example()
 {
     // Create a file rotating logger with 5mb size max and 3 rotated files.
     spdlog::file_event_handlers_t file_event_handlers;
-        file_event_handlers.after_open = [](spdlog::filename_t filename, std::FILE* fstream)
+    file_event_handlers.before_open = [](spdlog::filename_t filename)
+    {
+        spdlog::info("basic_example() : file_event_handlers.before_open     : {}", filename.c_str());
+    };
+    file_event_handlers.after_open = [](spdlog::filename_t filename, std::FILE* fstream)
     {
         fputs("OPEN!\r\n", fstream);
         spdlog::info("basic_example() : file_event_handlers.after_open      : {}", filename.c_str());

include/spdlog/common.h

@@ -256,11 +256,15 @@ struct source_loc
     const char *funcname{nullptr};
 };
 
-typedef struct 
+typedef struct file_event_handlers
 {
+    std::function<void(const filename_t &filename)> before_open;
     std::function<void(const filename_t &filename, std::FILE *file_stream)> after_open;
     std::function<void(const filename_t &filename, std::FILE *file_stream)> before_close;
     std::function<void(const filename_t &filename)> after_close;
+
+    file_event_handlers(): before_open(nullptr), after_open(nullptr), before_close(nullptr), after_close(nullptr)
+    {}
 } file_event_handlers_t;
 
 namespace details {

include/spdlog/details/file_helper-inl.h

@@ -37,6 +37,10 @@ SPDLOG_INLINE void file_helper::open(const filename_t &fname, bool truncate)
     auto *mode = SPDLOG_FILENAME_T("ab");
     auto *trunc_mode = SPDLOG_FILENAME_T("wb");
 
+    if (event_handlers_.before_open)
+    {
+        event_handlers_.before_open(filename_);
+    }
     for (int tries = 0; tries < open_tries_; ++tries)
     {
         // create containing folder if not exists already.

include/spdlog/details/file_helper.h

@@ -51,7 +51,7 @@ private:
     const unsigned int open_interval_ = 10;
     std::FILE *fd_{nullptr};
     filename_t filename_;
-    file_event_handlers_t event_handlers_{nullptr, nullptr, nullptr};
+    file_event_handlers_t event_handlers_;
 };
 } // namespace details
 } // namespace spdlog

include/spdlog/sinks/basic_file_sink.h

@@ -20,7 +20,7 @@ template<typename Mutex>
 class basic_file_sink final : public base_sink<Mutex>
 {
 public:
-    explicit basic_file_sink(const filename_t &filename, bool truncate = false, const file_event_handlers_t& event_handlers = {nullptr, nullptr, nullptr});
+    explicit basic_file_sink(const filename_t &filename, bool truncate = false, const file_event_handlers_t& event_handlers = {});
     const filename_t &filename() const;
 
 protected:
@@ -40,13 +40,13 @@ using basic_file_sink_st = basic_file_sink<details::null_mutex>;
 // factory functions
 //
 template<typename Factory = spdlog::synchronous_factory>
-inline std::shared_ptr<logger> basic_logger_mt(const std::string &logger_name, const filename_t &filename, bool truncate = false, const file_event_handlers_t& event_handlers = {nullptr, nullptr, nullptr})
+inline std::shared_ptr<logger> basic_logger_mt(const std::string &logger_name, const filename_t &filename, bool truncate = false, const file_event_handlers_t& event_handlers = {})
 {
     return Factory::template create<sinks::basic_file_sink_mt>(logger_name, filename, truncate, event_handlers);
 }
 
 template<typename Factory = spdlog::synchronous_factory>
-inline std::shared_ptr<logger> basic_logger_st(const std::string &logger_name, const filename_t &filename, bool truncate = false, const file_event_handlers_t& event_handlers = {nullptr, nullptr, nullptr})
+inline std::shared_ptr<logger> basic_logger_st(const std::string &logger_name, const filename_t &filename, bool truncate = false, const file_event_handlers_t& event_handlers = {})
 {
     return Factory::template create<sinks::basic_file_sink_st>(logger_name, filename, truncate, event_handlers);
 }

include/spdlog/sinks/daily_file_sink.h

@@ -68,7 +68,7 @@ class daily_file_sink final : public base_sink<Mutex>
 {
 public:
     // create daily file sink which rotates on given time
-    daily_file_sink(filename_t base_filename, int rotation_hour, int rotation_minute, bool truncate = false, uint16_t max_files = 0, const file_event_handlers_t& event_handlers = {nullptr, nullptr, nullptr})
+    daily_file_sink(filename_t base_filename, int rotation_hour, int rotation_minute, bool truncate = false, uint16_t max_files = 0, const file_event_handlers_t& event_handlers = {})
         : base_filename_(std::move(base_filename))
         , rotation_h_(rotation_hour)
         , rotation_m_(rotation_minute)
@@ -215,28 +215,28 @@ using daily_file_format_sink_st = daily_file_sink<details::null_mutex, daily_fil
 //
 template<typename Factory = spdlog::synchronous_factory>
 inline std::shared_ptr<logger> daily_logger_mt(
-    const std::string &logger_name, const filename_t &filename, int hour = 0, int minute = 0, bool truncate = false, uint16_t max_files = 0, const file_event_handlers_t& event_handlers = {nullptr, nullptr, nullptr})
+    const std::string &logger_name, const filename_t &filename, int hour = 0, int minute = 0, bool truncate = false, uint16_t max_files = 0, const file_event_handlers_t& event_handlers = {})
 {
     return Factory::template create<sinks::daily_file_sink_mt>(logger_name, filename, hour, minute, truncate, max_files, event_handlers);
 }
 
 template<typename Factory = spdlog::synchronous_factory>
 inline std::shared_ptr<logger> daily_logger_format_mt(
-    const std::string &logger_name, const filename_t &filename, int hour = 0, int minute = 0, bool truncate = false, uint16_t max_files = 0, const file_event_handlers_t& event_handlers = {nullptr, nullptr, nullptr})
+    const std::string &logger_name, const filename_t &filename, int hour = 0, int minute = 0, bool truncate = false, uint16_t max_files = 0, const file_event_handlers_t& event_handlers = {})
 {
     return Factory::template create<sinks::daily_file_format_sink_mt>(logger_name, filename, hour, minute, truncate, max_files, event_handlers);
 }
 
 template<typename Factory = spdlog::synchronous_factory>
 inline std::shared_ptr<logger> daily_logger_st(
-    const std::string &logger_name, const filename_t &filename, int hour = 0, int minute = 0, bool truncate = false, uint16_t max_files = 0, const file_event_handlers_t& event_handlers = {nullptr, nullptr, nullptr})
+    const std::string &logger_name, const filename_t &filename, int hour = 0, int minute = 0, bool truncate = false, uint16_t max_files = 0, const file_event_handlers_t& event_handlers = {})
 {
     return Factory::template create<sinks::daily_file_sink_st>(logger_name, filename, hour, minute, truncate, max_files, event_handlers);
 }
 
 template<typename Factory = spdlog::synchronous_factory>
 inline std::shared_ptr<logger> daily_logger_format_st(
-    const std::string &logger_name, const filename_t &filename, int hour = 0, int minute = 0, bool truncate = false, uint16_t max_files = 0, const file_event_handlers_t& event_handlers = {nullptr, nullptr, nullptr})
+    const std::string &logger_name, const filename_t &filename, int hour = 0, int minute = 0, bool truncate = false, uint16_t max_files = 0, const file_event_handlers_t& event_handlers = {})
 {
     return Factory::template create<sinks::daily_file_format_sink_st>(logger_name, filename, hour, minute, truncate, max_files, event_handlers);
 }

include/spdlog/sinks/hourly_file_sink.h

@@ -46,7 +46,7 @@ class hourly_file_sink final : public base_sink<Mutex>
 {
 public:
     // create hourly file sink which rotates on given time
-    hourly_file_sink(filename_t base_filename, bool truncate = false, uint16_t max_files = 0, const file_event_handlers_t& event_handlers = {nullptr, nullptr, nullptr})
+    hourly_file_sink(filename_t base_filename, bool truncate = false, uint16_t max_files = 0, const file_event_handlers_t& event_handlers = {})
         : base_filename_(std::move(base_filename))
         , file_helper_{event_handlers}
         , truncate_(truncate)
@@ -181,14 +181,14 @@ using hourly_file_sink_st = hourly_file_sink<details::null_mutex>;
 //
 template<typename Factory = spdlog::synchronous_factory>
 inline std::shared_ptr<logger> hourly_logger_mt(
-    const std::string &logger_name, const filename_t &filename, bool truncate = false, uint16_t max_files = 0, const file_event_handlers_t& event_handlers = {nullptr, nullptr, nullptr})
+    const std::string &logger_name, const filename_t &filename, bool truncate = false, uint16_t max_files = 0, const file_event_handlers_t& event_handlers = {})
 {
     return Factory::template create<sinks::hourly_file_sink_mt>(logger_name, filename, truncate, max_files, event_handlers);
 }
 
 template<typename Factory = spdlog::synchronous_factory>
 inline std::shared_ptr<logger> hourly_logger_st(
-    const std::string &logger_name, const filename_t &filename, bool truncate = false, uint16_t max_files = 0, const file_event_handlers_t& event_handlers = {nullptr, nullptr, nullptr})
+    const std::string &logger_name, const filename_t &filename, bool truncate = false, uint16_t max_files = 0, const file_event_handlers_t& event_handlers = {})
 {
     return Factory::template create<sinks::hourly_file_sink_st>(logger_name, filename, truncate, max_files, event_handlers);
 }

include/spdlog/sinks/rotating_file_sink.h

@@ -22,7 +22,7 @@ template<typename Mutex>
 class rotating_file_sink final : public base_sink<Mutex>
 {
 public:
-    rotating_file_sink(filename_t base_filename, std::size_t max_size, std::size_t max_files, bool rotate_on_open = false, const file_event_handlers_t& event_handlers = {nullptr, nullptr, nullptr});
+    rotating_file_sink(filename_t base_filename, std::size_t max_size, std::size_t max_files, bool rotate_on_open = false, const file_event_handlers_t& event_handlers = {});
     static filename_t calc_filename(const filename_t &filename, std::size_t index);
     filename_t filename();
 
@@ -60,14 +60,14 @@ using rotating_file_sink_st = rotating_file_sink<details::null_mutex>;
 
 template<typename Factory = spdlog::synchronous_factory>
 inline std::shared_ptr<logger> rotating_logger_mt(
-    const std::string &logger_name, const filename_t &filename, size_t max_file_size, size_t max_files, bool rotate_on_open = false, const file_event_handlers_t& event_handlers = {nullptr, nullptr, nullptr})
+    const std::string &logger_name, const filename_t &filename, size_t max_file_size, size_t max_files, bool rotate_on_open = false, const file_event_handlers_t& event_handlers = {})
 {
     return Factory::template create<sinks::rotating_file_sink_mt>(logger_name, filename, max_file_size, max_files, rotate_on_open, event_handlers);
 }
 
 template<typename Factory = spdlog::synchronous_factory>
 inline std::shared_ptr<logger> rotating_logger_st(
-    const std::string &logger_name, const filename_t &filename, size_t max_file_size, size_t max_files, bool rotate_on_open = false, const file_event_handlers_t& event_handlers = {nullptr, nullptr, nullptr})
+    const std::string &logger_name, const filename_t &filename, size_t max_file_size, size_t max_files, bool rotate_on_open = false, const file_event_handlers_t& event_handlers = {})
 {
     return Factory::template create<sinks::rotating_file_sink_st>(logger_name, filename, max_file_size, max_files, rotate_on_open, event_handlers);
 }