Formatter

struct Formatter : IFormatter {
    string format (std::string& msg, const Info& info) const override {
        std::stringstream ss;
        ss << info.file <<  ":" << to_string(info.line) << "\t" << msg << std::endl;
        auto ret = ss.str();
        return string(ret.data(), ret.size());
    }
};
set_formatter(new Formatter());

Formatter is an object that produce a string from all the information provided by logging library and user.

To customize format implement IFormatter an overload string format (std::string& msg, const Info& info) const method. msg is a message passed to log macro(i.e. panda_log_debug) and info is additional information:

• Level level - log level: debug, info, error, etc...
• const Module* module - pointer to module object. See Modules
• string_view file - name of source file containing the logging call
• uint32_t line - line in a source file
• string_view func- short name of a function containing the logging call
• time_point time - curent time
• string_view program_name - a name of program. Process name by default, can be changed by set_program_name

Pattern Formater

A formatter based on a pattern string. It is printf-like string. Tokens can look like %X or %xX or %.yX or %x.yX. x and y are tokent's digital arguments like precision for doubles in printf. I.e. %2.3t is a time HH:MM:SS and 3 digits of milliseconds.

%L - level

%M - module. if module has no name (root), removes x chars on the left and y chars on the right.

%F - function

%f - file

• x=0: only file name
• x=1: full path as it appeared during compilation

%l - line

%m - message

• x=0: default multiline message behaviour
• x=1: decorate each line of multiline message

%t - current time

• x=0: YYYY-MM-DD HH:MM:SS
• x=1: YY-MM-DD HH:MM:SS
• x=2: HH:MM:SS
• x=3: UNIX TIMESTAMP
• x=4: YYYY/MM/DD HH:MM:SS
• y>0: high resolution time, adds fractional part after seconds with "y" digits precision

%T - current thread id

%p - current process id

%P - current process title

%c - start color

%C - end color