Cleaned up logging

Author: Lauris Kaplinski

cdoc/CDoc.cpp

@@ -21,7 +21,7 @@
 #include "CDoc2Writer.h"
 #include "CDoc2Reader.h"
 #include "Configuration.h"
-#include "ILogger.h"
+#include "ConsoleLogger.h"
 #include "Io.h"
 #include "NetworkBackend.h"
 
@@ -71,6 +71,28 @@ getVersion()
     return VERSION_STR;
 }
 
+static Logger *
+getDefaultLogger()
+{
+    static ConsoleLogger clogger;
+    return &clogger;
+}
+
+static Logger *sys_logger = nullptr;
+
+void
+setLogger(Logger *logger)
+{
+    sys_logger = logger;
+}
+
+void
+log(LogLevel level, std::string_view file, int line, std::string_view msg)
+{
+    Logger *logger = (sys_logger) ? sys_logger : getDefaultLogger();
+    logger->log(level, file, line, msg);
+}
+
 int
 libcdoc::CDocReader::getCDocFileVersion(DataSource *src)
 {

cdoc/CDoc.h

@@ -134,6 +134,50 @@ CDOC_EXPORT std::string getErrorStr(int64_t code);
 
 CDOC_EXPORT std::string getVersion();
 
+// Logging interface
+
+class ILogger;
+typedef ILogger Logger;
+
+/**
+ * @brief Log-level enumeration to indicate severity of the log message.
+ */
+enum LogLevel
+{
+    /**
+     * @brief Most critical level. Application is about to abort.
+     */
+    LEVEL_FATAL,
+
+    /**
+     * @brief Errors where functionality has failed or an exception have been caught.
+     */
+    LEVEL_ERROR,
+
+    /**
+     * @brief Warnings about validation issues or temporary failures that can be recovered.
+     */
+    LEVEL_WARNING,
+
+    /**
+     * @brief Information that highlights progress or application lifetime events.
+     */
+    LEVEL_INFO,
+
+    /**
+     * @brief Debugging the application behavior from internal events of interest.
+     */
+    LEVEL_DEBUG,
+
+    /**
+     * @brief Most verbose level. Used for development, NOP in production code.
+     */
+    LEVEL_TRACE
+};
+
+CDOC_EXPORT void setLogger(Logger *logger);
+CDOC_EXPORT void log(LogLevel level, std::string_view file, int line, std::string_view msg);
+
 /**
  * @brief A simple container of file name and size
  *

cdoc/CMakeLists.txt

@@ -38,7 +38,6 @@ add_library(cdoc
     CryptoBackend.cpp
     NetworkBackend.cpp
     PKCS11Backend.cpp
-    LogEngine.cpp
     $<$<PLATFORM_ID:Windows>:WinBackend.cpp>
     Certificate.cpp Certificate.h
     Crypto.cpp Crypto.h

cdoc/ConsoleLogger.h

@@ -35,14 +35,11 @@ namespace libcdoc
 class ConsoleLogger : public ILogger
 {
 public:
-    virtual void LogMessage(LogLevel level, std::string_view file, int line, std::string_view message) override
+    virtual void logMessage(LogLevel level, std::string_view file, int line, std::string_view message) override
     {
         // We ignore by default the file name and line number, and call LogMessage with the level and message.
-        if (level <= minLogLevel)
-        {
-            std::ostream& ofs = (level == LEVEL_INFO) ? std::cout : std::cerr;
-            ofs << message << '\n';
-        }
+        std::ostream& ofs = (level == LEVEL_INFO) ? std::cout : std::cerr;
+        ofs << message << '\n';
     }
 };
 

cdoc/Crypto.cpp

@@ -426,7 +426,7 @@ void Crypto::LogSslError(const char* funcName, const char* file, int line)
     while (errorCode != 0)
     {
         ERR_error_string_n(errorCode, sslErrorStr, errorStrBufLen);
-        ILogger::getLogger()->LogMessage(ILogger::LEVEL_ERROR, file, line, FORMAT("{} failed: {}", funcName, sslErrorStr));
+        LOG_ERROR("{} failed: {}", funcName, sslErrorStr);
 
         // Get next error code
         errorCode = ERR_get_error();

cdoc/ILogger.h

@@ -31,6 +31,8 @@ namespace fmt = std;
 #include "fmt/format.h"
 #endif
 
+#include <CDoc.h>
+
 #define FORMAT fmt::format
 
 namespace libcdoc
@@ -42,62 +44,19 @@ namespace libcdoc
 class CDOC_EXPORT ILogger
 {
 public:
-    /**
-     * @brief Log-level enumeration to indicate severity of the log message.
-     */
-    enum LogLevel
-    {
-        /**
-         * @brief Most critical level. Application is about to abort.
-         */
-        LEVEL_FATAL,
-
-        /**
-         * @brief Errors where functionality has failed or an exception have been caught.
-         */
-        LEVEL_ERROR,
-
-        /**
-         * @brief Warnings about validation issues or temporary failures that can be recovered.
-         */
-        LEVEL_WARNING,
-
-        /**
-         * @brief Information that highlights progress or application lifetime events.
-         */
-        LEVEL_INFO,
-
-        /**
-         * @brief Debugging the application behavior from internal events of interest.
-         */
-        LEVEL_DEBUG,
-
-        /**
-         * @brief Most verbose level. Used for development, NOP in production code.
-         */
-        LEVEL_TRACE
-    };
-
-    ILogger() : minLogLevel(LEVEL_WARNING) {}
-    virtual ~ILogger() {}
-
     /**
      * @brief Logs given message with given severity, file name and line number.
+     * 
+     * It tests the log level and if <= min_level invokes logMessage
+     * 
      * @param level Severity of the log message.
      * @param file File name where the log message was recorded.
      * @param line Line number in the file where the log message was recorded.
-     * @param message The log message.
-     *
-     * Every class implementing the ILogger interface must implement the member function.
-     * Default implementation does nothing.
+     * @param msg The log message.
      */
-    virtual void LogMessage(LogLevel level, std::string_view file, int line, std::string_view message) {}
-
-    /**
-     * @brief Returns current minimum log level of the logger.
-     * @return Minimum log level.
-     */
-    LogLevel GetMinLogLevel() const noexcept { return minLogLevel; }
+    void log(LogLevel level, std::string_view file, int line, std::string_view msg) {
+        if (level <= min_level) logMessage(level, file, line, msg);
+    }
 
     /**
      * @brief Sets minimum log level for the logger.
@@ -107,68 +66,56 @@ class CDOC_EXPORT ILogger
      * to LogLevelInfo (default), then LogLevelFatal, LogLevelError, LogLevelWarning and LogLevelInfo
      * messages are logged, but not LogLevelDebug or LogLevelTrace messages.
      */
-    void SetMinLogLevel(LogLevel level) noexcept { minLogLevel = level; }
-
+    void setMinLogLevel(LogLevel level) noexcept { min_level = level; }
+protected:
     /**
-     * @brief Adds ILogger implementation to logging queue.
+     * @brief Logs given message with given severity, file name and line number.
      * 
-     * This function does not take ownership of the logger's instance.
-     * It is up to the caller to free the resources of the logger's instance and 
-     * keep it alive until removed from the queue.
+     * Every class implementing the ILogger interface must implement this member function.
+     * The efault implementation does nothing.
+     * The level should be checked by caller, thus the implementation should expect that level <= min_level
      * 
-     * @param logger Logger's instance to be added.
-     * @return Unique cookie identifying the logger's instance in the logging queue.
-     */
-    static int addLogger(ILogger* logger);
-
-    /**
-     * @brief Removes logger's instance from the logging queue.
-     * @param cookie Unique cookie returned by the add_logger function when the logger was added.
-     * @return Pointer to ILogger object that is removed. It's up to user to free the resources.
-     */
-    static ILogger* removeLogger(int cookie);
-
-    /**
-     * @brief Returns global logger's instance.
-     * @return Global logger's instance.
+     * @param level Severity of the log message.
+     * @param file File name where the log message was recorded.
+     * @param line Line number in the file where the log message was recorded.
+     * @param msg The log message.
      */
-    static ILogger* getLogger();
+    virtual void logMessage(LogLevel level, std::string_view file, int line, std::string_view msg) {}
 
-    static void setLogger(ILogger *logger);
-
-protected:
     /**
      * @brief Minimum level of log messages to log.
      */
-    LogLevel minLogLevel;
+    LogLevel min_level = LEVEL_WARNING;
 };
 
+typedef ILogger Logger;
+
 #ifndef SWIG
 template<typename... Args>
-static inline void LogFormat(ILogger::LogLevel level, std::string_view file, int line, fmt::format_string<Args...> fmt, Args&&... args)
+static inline void LogFormat(LogLevel level, std::string_view file, int line, fmt::format_string<Args...> fmt, Args&&... args)
 {
     auto msg = fmt::format(fmt, std::forward<Args>(args)...);
-    ILogger::getLogger()->LogMessage(level, file, line, msg);
+    libcdoc::log(level, file, line, msg);
 }
 
-static inline void LogFormat(ILogger::LogLevel level, std::string_view file, int line, std::string_view msg)
+static inline void LogFormat(LogLevel level, std::string_view file, int line, std::string_view msg)
 {
-    ILogger::getLogger()->LogMessage(level, file, line, msg);
+    libcdoc::log(level, file, line, msg);
 }
 #endif
 
 #define LOG(l,...) LogFormat((l), __FILE__, __LINE__, __VA_ARGS__)
-#define LOG_ERROR(...) LogFormat(libcdoc::ILogger::LEVEL_ERROR, __FILE__, __LINE__, __VA_ARGS__)
-#define LOG_WARN(...) LogFormat(libcdoc::ILogger::LEVEL_WARNING, __FILE__, __LINE__, __VA_ARGS__)
-#define LOG_INFO(...) LogFormat(libcdoc::ILogger::LEVEL_INFO, __FILE__, __LINE__, __VA_ARGS__)
-#define LOG_DBG(...) LogFormat(libcdoc::ILogger::LEVEL_DEBUG, __FILE__, __LINE__, __VA_ARGS__)
+#define LOG_ERROR(...) LogFormat(libcdoc::LEVEL_ERROR, __FILE__, __LINE__, __VA_ARGS__)
+#define LOG_WARN(...) LogFormat(libcdoc::LEVEL_WARNING, __FILE__, __LINE__, __VA_ARGS__)
+#define LOG_INFO(...) LogFormat(libcdoc::LEVEL_INFO, __FILE__, __LINE__, __VA_ARGS__)
+#define LOG_DBG(...) LogFormat(libcdoc::LEVEL_DEBUG, __FILE__, __LINE__, __VA_ARGS__)
 
 #ifdef NDEBUG
 #define LOG_TRACE(...)
 #define LOG_TRACE_KEY(MSG, KEY)
 #else
-#define LOG_TRACE(...) LogFormat(libcdoc::ILogger::LEVEL_TRACE, __FILE__, __LINE__, __VA_ARGS__)
-#define LOG_TRACE_KEY(MSG, KEY) LogFormat(libcdoc::ILogger::LEVEL_TRACE, __FILE__, __LINE__, MSG, toHex(KEY))
+#define LOG_TRACE(...) LogFormat(libcdoc::LEVEL_TRACE, __FILE__, __LINE__, __VA_ARGS__)
+#define LOG_TRACE_KEY(MSG, KEY) LogFormat(libcdoc::LEVEL_TRACE, __FILE__, __LINE__, MSG, toHex(KEY))
 #endif
 
 }