Replace OpenDebugLog() with StartLogging()

StartLogging() is used to mark the start of logging generically, whether
using -printtoconsole or -debuglogfile.

Author: ajtowns

src/init.cpp

@@ -1249,10 +1249,10 @@ bool AppInitMain(InitInterfaces& interfaces)
             // and because this needs to happen before any other debug.log printing
             LogInstance().ShrinkDebugFile();
         }
-        if (!LogInstance().OpenDebugLog()) {
+    }
+    if (!LogInstance().StartLogging()) {
             return InitError(strprintf("Could not open debug log file %s",
                 LogInstance().m_file_path.string()));
-        }
     }
 
     if (!LogInstance().m_log_timestamps)

src/logging.cpp

@@ -39,9 +39,10 @@ static int FileWriteStr(const std::string &str, FILE *fp)
     return fwrite(str.data(), 1, str.size(), fp);
 }
 
-bool BCLog::Logger::OpenDebugLog()
+bool BCLog::Logger::StartLogging()
 {
     std::lock_guard<std::mutex> scoped_lock(m_file_mutex);
+    if (!m_print_to_file) return true;
 
     assert(m_fileout == nullptr);
     assert(!m_file_path.empty());

src/logging.h

@@ -93,7 +93,7 @@ namespace BCLog {
         /** Returns whether logs will be written to any output */
         bool Enabled() const { return m_print_to_console || m_print_to_file; }
 
-        bool OpenDebugLog();
+        bool StartLogging();
         void ShrinkDebugFile();
 
         uint32_t GetCategoryMask() const { return m_categories.load(); }