fix lock (#414)

include/ylt/easylog/appender.hpp

@@ -27,6 +27,10 @@
 #include "ylt/util/concurrentqueue.h"
 
 namespace easylog {
+struct empty_mutex {
+  void lock() {}
+  void unlock() {}
+};
 constexpr inline std::string_view BOM_STR = "\xEF\xBB\xBF";
 
 constexpr char digits[10] = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9'};
@@ -114,7 +118,8 @@ class appender {
         if (stop_) {
           if (queue_.size_approx() > 0) {
             while (queue_.try_dequeue(record)) {
-              write_record(record);
+              enable_console_ ? write_record<false, true>(record)
+                              : write_record<false, false>(record);
             }
           }
         }
@@ -140,14 +145,22 @@ class appender {
     return {buf, last_len};
   }
 
+  template <bool sync>
+  auto &get_mutex() {
+    if constexpr (sync) {
+      return mtx_;
+    }
+    else {
+      return empty_mtx_;
+    }
+  }
+
   template <bool sync = false, bool enable_console = false>
   void write_record(record_t &record) {
+    std::lock_guard guard(get_mutex<sync>());
     if constexpr (sync == true) {
-      std::shared_lock guard(mtx_);
       if (max_files_ > 0 && file_size_ > max_file_size_ &&
           static_cast<size_t>(-1) != file_size_) {
-        guard.unlock();
-        std::lock_guard lock{mtx_};
         roll_log_files();
       }
     }
@@ -159,33 +172,31 @@ class appender {
     buf[32] = ' ';
 
     if constexpr (enable_console) {
-      if constexpr (sync) {
-        std::lock_guard guard(console_mtx_);
-        add_color(record.get_severity());
-      }
-      else {
-        add_color(record.get_severity());
-      }
+      add_color(record.get_severity());
     }
 
-    write_str<sync, enable_console>(std::string_view(buf, 33));
+    std::string_view str(buf, 33);
+
+    write_file(str);
 
     if constexpr (enable_console) {
+      std::cout << str;
       clean_color(record.get_severity());
     }
 
-    write_str<sync, enable_console>(get_tid_buf(record.get_tid()));
-    write_str<sync, enable_console>(record.get_file_str());
-    write_str<sync, enable_console>(record.get_message());
+    auto tid_str = get_tid_buf(record.get_tid());
+    auto file_str = record.get_file_str();
+    auto msg = record.get_message();
+
+    write_file(tid_str);
+    write_file(file_str);
+    write_file(msg);
 
     if constexpr (enable_console) {
-      if constexpr (sync) {
-        std::lock_guard guard(console_mtx_);
-        std::cout << std::flush;
-      }
-      else {
-        std::cout << std::flush;
-      }
+      std::cout << tid_str;
+      std::cout << file_str;
+      std::cout << msg;
+      std::cout << std::flush;
     }
   }
 
@@ -304,7 +315,6 @@ class appender {
       if (file_size == 0) {
         if (file_.write(BOM_STR.data(), BOM_STR.size())) {
           file_size_ += BOM_STR.size();
-          is_first_write_ = false;
         }
       }
     }
@@ -346,11 +356,9 @@ class appender {
     }
 
     open_log_file();
-    is_first_write_ = false;
   }
 
-  template <bool sync, bool enable_console>
-  void write_str(std::string_view str) {
+  void write_file(std::string_view str) {
     if (has_init_) {
       if (file_.write(str.data(), str.size())) {
         if (flush_every_time_) {
@@ -360,16 +368,6 @@ class appender {
         file_size_ += str.size();
       }
     }
-
-    if constexpr (enable_console) {
-      if constexpr (sync) {
-        std::lock_guard guard(console_mtx_);
-        std::cout << str;
-      }
-      else {
-        std::cout << str;
-      }
-    }
   }
 
   bool has_init_ = false;
@@ -380,11 +378,9 @@ class appender {
   size_t file_size_ = 0;
   size_t max_file_size_ = 0;
   size_t max_files_ = 0;
-  bool is_first_write_ = true;
-
-  std::mutex console_mtx_;
 
   std::shared_mutex mtx_;
+  empty_mutex empty_mtx_;
   std::ofstream file_;
 
   std::mutex que_mtx_;