Logger

Simple and high-performance log module based on C/C++

Basic features are as follows

• Prints log to standard output.
• Prints log to the specified log file.
• Filter logs based on log levels.

Also you can

• Change log format through inheritance.
• Use threaded Logger for high performance (but some log can be lost when Queue is full)

UML class diagram

Logger module

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Install (Logger module)

$ mkdir build                # Make a build directory
$ cd build                   # Change to the build directory
$ cmake ..                   # Create a Makefile
$ make                       # Make a libray file
$ make install               # Install header and library files
$ ls -al ../release/include  # You can check a header file
$ ls -al ../release/lib      # You can check a library file

Test

### "Install" is required before testing.
$ cd test                    # Change to the test directory
$ mkdir build                # Make a build directory
$ cd build                   # Change to the build directory
$ cmake ..                   # Create a Makefile
$ make                       # Make a binary file
$ ./main                     # Run test

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Examples

SimpleLogger

• Simple logger.

//
// Set namespace
//
using namespace vp;

//
// Define log macros
//
#define LOG_TRC(...)  _LOG_TRC(logger, __VA_ARGS__)
#define LOG_DBG(...)  _LOG_DBG(logger, __VA_ARGS__)
#define LOG_INFO(...) _LOG_INFO(logger, __VA_ARGS__)
#define LOG_WARN(...) _LOG_WARN(logger, __VA_ARGS__)
#define LOG_ERR(...)  _LOG_ERR(logger, __VA_ARGS__)

SimpleLogger logger;

//
// Bassic logger settings
//
{
  ALogger &abst = logger;
  abst.setFilePath("."); // Set the log file path
  abst.setFileName("test.log"); // Set the log file name
  abst.setMaxLogLength(4096); // Set the maximum log length
  abst.setLogStdoutEnabled(true); // Enable printing log to standard output
  abst.setLogLevel(LogLevel::LOG_LEVEL_ALL); // LogLevel::LOG_LEVEL_ALL for all Log Levels.
      // You can set multiple log levels using the logical operation "|".
      // For example, if you set Log level as LogLevel::LOG_LEVEL_WARNING | LogLevel::LOG_LEVEL_ERROR,
      // only “Error” and “Warning” will be printed.
}

//
// Initialize the logger
//
if (logger.initialize() != RetType::RET_SUCCESS) {
  fprintf(stderr, "Failed to initialize logger\n");
  return -1;
}

LOG_TRC( "Hello world!! [T]");
LOG_DBG( "Hello world!! [D]");
LOG_INFO("Hello world!! [I]");
LOG_WARN("Hello world!! [W]");
LOG_ERR( "Hello world!! [E]");

//
// Finalize the logger
//
if (logger.finalize() != RetType::RET_SUCCESS) {
  fprintf(stderr, "Failed to finalize logger\n");
  return -1;
}

ThreadedLogger

• Threaded logger. (High-performance)
• A logger thread will be created. And in this thread, log will be written in a log file.

//
// Set namespace
//
using namespace vp;

//
// Define log macros
//
#define LOG_TRC(...)  _LOG_TRC(logger, __VA_ARGS__)
#define LOG_DBG(...)  _LOG_DBG(logger, __VA_ARGS__)
#define LOG_INFO(...) _LOG_INFO(logger, __VA_ARGS__)
#define LOG_WARN(...) _LOG_WARN(logger, __VA_ARGS__)
#define LOG_ERR(...)  _LOG_ERR(logger, __VA_ARGS__)

ThreadedLogger logger;

//
// Bassic logger settings
//
{
  ALogger &abst = logger;
  abst.setFilePath("."); // Set the log file path
  abst.setFileName("test.log"); // Set the log file name
  abst.setMaxLogLength(4096); // Set the maximum log length
  abst.setLogStdoutEnabled(true); // Enable printing log to standard output
  abst.setLogLevel(LogLevel::LOG_LEVEL_ALL); // LogLevel::LOG_LEVEL_ALL for all Log Levels.
      // You can set multiple log levels using the logical operation "|".
      // For example, if you set Log level as LogLevel::LOG_LEVEL_WARNING | LogLevel::LOG_LEVEL_ERROR,
      // only “Error” and “Warning” will be printed.
}

//
// Threaded logger settings
//
{
  logger.setMaxQueueSize(8192); // Set the maximum queue size (Default 4096)
  logger.setPollingSleepUs(1); // Set the polling sleep time in micro seconds (0 means no sleep but polling, Default 1000)
}

//
// Initialize the logger
//
if (logger.initialize() != RetType::RET_SUCCESS) {
  fprintf(stderr, "Failed to initialize logger\n");
  return -1;
}

//
// Print log
//
LOG_TRC( "Hello world!! [T]");
LOG_DBG( "Hello world!! [D]");
LOG_INFO("Hello world!! [I]");
LOG_WARN("Hello world!! [W]");
LOG_ERR( "Hello world!! [E]");

//
// Finalize the logger
//
if (logger.finalize() != RetType::RET_SUCCESS) {
  fprintf(stderr, "Failed to finalize logger\n");
  return -1;
}

SimpleLogger with a user log formatter

• Users can set their own log format

//
// Set namespace
//
using namespace vp;

//
// Define log macros
//
#define LOG_TRC(...)  _LOG_TRC(logger, __VA_ARGS__)
#define LOG_DBG(...)  _LOG_DBG(logger, __VA_ARGS__)
#define LOG_INFO(...) _LOG_INFO(logger, __VA_ARGS__)
#define LOG_WARN(...) _LOG_WARN(logger, __VA_ARGS__)
#define LOG_ERR(...)  _LOG_ERR(logger, __VA_ARGS__)

//
// User log formatter class
//
class UserLogFormatter : public ILogFormatter
{
public:
  UserLogFormatter() = default;
  virtual ~UserLogFormatter() = default;
  virtual auto format(char *pzLogBuffer, int nLogBufferLength,
            LogLevel eLogLevel, const char *pzFileName, const char *pzFunctionName, int nLine,
            const char *pzFormat, va_list &vaList) -> int
  {
    int nLength = 0;
    nLength = snprintf(pzLogBuffer, nLogBufferLength, "[%02ld] [%s:%d] [%s] ", eLogLevel, pzFileName, nLine, pzFunctionName);
    nLength += vsnprintf(pzLogBuffer + nLength, nLogBufferLength - nLength, pzFormat, vaList);
    return nLength;
  }
};

SimpleLogger logger;
UserLogFormatter fomatter;

//
// Bassic logger settings
//
{
  ALogger &abst = logger;
  abst.setFilePath("."); // Set the log file path
  abst.setFileName("test.log"); // Set the log file name
  abst.setMaxLogLength(4096); // Set the maximum log length
  abst.setLogStdoutEnabled(true); // Enable printing log to standard output
  abst.setLogLevel(LogLevel::LOG_LEVEL_ALL); // LogLevel::LOG_LEVEL_ALL for all Log Levels.
      // You can set multiple log levels using the logical operation "|".
      // For example, if you set Log level as LogLevel::LOG_LEVEL_WARNING | LogLevel::LOG_LEVEL_ERROR,
      // only “Error” and “Warning” will be printed.
  abst.setLogFormatter(&fomatter); // Set a user log formatter
}

//
// Initialize the logger
//
if (logger.initialize() != RetType::RET_SUCCESS) {
  fprintf(stderr, "Failed to initialize logger\n");
  return -1;
}

//
// Print log
//
LOG_TRC( "Hello world!! [T]");
LOG_DBG( "Hello world!! [D]");
LOG_INFO("Hello world!! [I]");
LOG_WARN("Hello world!! [W]");
LOG_ERR( "Hello world!! [E]");

//
// Finalize the logger
//
if (logger.finalize() != RetType::RET_SUCCESS) {
  fprintf(stderr, "Failed to finalize logger\n");
  return -1;
}

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Please let me know if there is any bug or feature you would like to use.
Thank you. :)