logging: refactor: pull prefix code out

Author: ajtowns

src/logging.cpp

@@ -202,7 +202,7 @@ bool GetLogCategory(BCLog::LogFlags& flag, const std::string& str)
     return false;
 }
 
-std::string BCLog::Logger::LogLevelToStr(BCLog::Level level) const
+std::string BCLog::Logger::LogLevelToStr(BCLog::Level level)
 {
     switch (level) {
     case BCLog::Level::Trace:
@@ -341,7 +341,7 @@ static constexpr std::array<BCLog::Level, 3> LogLevelsList()
 std::string BCLog::Logger::LogLevelsString() const
 {
     const auto& levels = LogLevelsList();
-    return Join(std::vector<BCLog::Level>{levels.begin(), levels.end()}, ", ", [this](BCLog::Level level) { return LogLevelToStr(level); });
+    return Join(std::vector<BCLog::Level>{levels.begin(), levels.end()}, ", ", [](BCLog::Level level) { return LogLevelToStr(level); });
 }
 
 std::string BCLog::Logger::LogTimestampStr(const std::string& str)
@@ -392,12 +392,9 @@ namespace BCLog {
     }
 } // namespace BCLog
 
-void BCLog::Logger::LogPrintStr(const std::string& str, const std::string& logging_function, const std::string& source_file, int source_line, BCLog::LogFlags category, BCLog::Level level)
+std::string BCLog::Logger::GetLogPrefix(BCLog::LogFlags category, BCLog::Level level) const
 {
-    StdLockGuard scoped_lock(m_cs);
-    std::string str_prefixed = LogEscapeMessage(str);
-
-    if ((category != LogFlags::NONE || level != Level::None) && m_started_new_line) {
+    if (category != LogFlags::NONE || level != Level::None) {
         std::string s{"["};
 
         if (category != LogFlags::NONE) {
@@ -414,7 +411,18 @@ void BCLog::Logger::LogPrintStr(const std::string& str, const std::string& loggi
         }
 
         s += "] ";
-        str_prefixed.insert(0, s);
+        return s;
+    }
+    return {};
+}
+
+void BCLog::Logger::LogPrintStr(const std::string& str, const std::string& logging_function, const std::string& source_file, int source_line, BCLog::LogFlags category, BCLog::Level level)
+{
+    StdLockGuard scoped_lock(m_cs);
+    std::string str_prefixed = LogEscapeMessage(str);
+
+    if (m_started_new_line) {
+        str_prefixed.insert(0, GetLogPrefix(category, level));
     }
 
     if (m_log_sourcelocations && m_started_new_line) {

src/logging.h

@@ -124,6 +124,8 @@ namespace BCLog {
         fs::path m_file_path;
         std::atomic<bool> m_reopen_file{false};
 
+        std::string GetLogPrefix(LogFlags category, Level level) const;
+
         /** Send a string to the log output */
         void LogPrintStr(const std::string& str, const std::string& logging_function, const std::string& source_file, int source_line, BCLog::LogFlags category, BCLog::Level level);
 
@@ -194,7 +196,7 @@ namespace BCLog {
         std::string LogLevelsString() const;
 
         //! Returns the string representation of a log level.
-        std::string LogLevelToStr(BCLog::Level level) const;
+        static std::string LogLevelToStr(BCLog::Level level);
 
         bool DefaultShrinkDebugFile() const;
     };

src/test/logging_tests.cpp

@@ -87,6 +87,7 @@ BOOST_FIXTURE_TEST_CASE(logging_LogPrintf_, LogSetup)
     LogPrintf_("fn2", "src2", 2, BCLog::LogFlags::NET, BCLog::Level::None, "foo2: %s\n", "bar2");
     LogPrintf_("fn3", "src3", 3, BCLog::LogFlags::NONE, BCLog::Level::Debug, "foo3: %s\n", "bar3");
     LogPrintf_("fn4", "src4", 4, BCLog::LogFlags::NONE, BCLog::Level::None, "foo4: %s\n", "bar4");
+    LogPrintf_("fn5", "src5", 5, BCLog::LogFlags::NONE, BCLog::Level::Info, "foo5: %s\n", "bar5");
     std::ifstream file{tmp_log_path};
     std::vector<std::string> log_lines;
     for (std::string log; std::getline(file, log);) {
@@ -97,6 +98,7 @@ BOOST_FIXTURE_TEST_CASE(logging_LogPrintf_, LogSetup)
         "[src2:2] [fn2] [net] foo2: bar2",
         "[src3:3] [fn3] [debug] foo3: bar3",
         "[src4:4] [fn4] foo4: bar4",
+        "[src5:5] [fn5] [info] foo5: bar5",
     };
     BOOST_CHECK_EQUAL_COLLECTIONS(log_lines.begin(), log_lines.end(), expected.begin(), expected.end());
 }