p≡p Logger

Introduction

The p≡p Logger is a fork of the Logger module of the p≡p JSON Server Adapter.

Features

• compile-time configurable via logger_config.hh, run-time configuable via API functions

• supports logging to syslog (UN*X only), to a file and to the console (stderr).

• supports log levels ("severities" in syslog terminology) and run-time filtering of log entries lower than given "log level"

• API for both printf()-like ("C") style and C++ outputstream-like style

• compile-time disabling of debug messages via -D DEBUG_ENABLED (if done via macros, see below)

• hierarchical Logger instances that inherit their "name" and their log level from their parent Logger instance

• multi-line log messages, visualized via big square brackets

• auto wrapping of long log lines, visualized via "↩" and "↪" (configurable at run-time via Logger::setMaxLineLength() )

• log GMT / UTC timestamp and easily greppable thread IDs. The thread IDh have the form ¶XYZ where 'XYZ' is a hash of std::this_thread::get_id(), truncated to three base-37 digits, to make collisions of thread IDs unlikely.

• logfile analyzer (e.g. for filtering log of different threads) via HTML & Javascript, see html/logview.html

TODOs

• truncating of pathologically long log messages, visualized via "▒ (%u octets clipped)" (configurable at run-time via Logger::setMaxMessageLength() )

• escaping of non-printing control characters, illegal Unicode codepoints and illegal UTF-8 sequences

Building

Dependencies

• C++14 compiler: tested with clang++ 10, g++ 11. Newer versions should work, too.
• GNU make

Building/Installing (Linux and macOS)

It is so simple. This should do out of the box:

make test

Building/Installing (Windows)

TODO.

Using the Logger in your own code

See examples in src/unittest_logger.cc