Doomsday Manual

stub

This article summarizes the coding conventions and practices used in Doomsday 2.0 (libdeng2 library).

• more modular: core, legacy, data, network already present, more to come
• everything in “include/de” is the public API
• non-public headers go to the module's src dir
• Qt-like convenience includes with class name, e.g. “include/de/Log”
• copyright banner should be updated to match the new format in libdeng1 (with @file, @authors, <small> GPL text)
• library-wide defines have a DENG2_ prefix (DENG2_USE_QT, DENG2_64BIT, DENG2_PUBLIC, DENG2_ASSERT)
• all C APIs should go to c_wrapper.h
• exports are marked with DENG2_PUBLIC (no .def files on Windows)
• all basic number types should use the d* typedefs in libdeng2.h
• the data module is important to know by heart: serialization, locking, byte array and string operations, time/date
• everything goes in “namespace de”
• error situations are handled via exceptions (see usage of DENG2_ERROR, DENG2_SUB_ERROR through the modules)
• error exceptions need to include both function name and the error description (without a period in the end) – see the existing throws in the code
• beware: exceptions cannot be allowed to reach to the libdeng1 one (kills the app immediately); they must be caught in C wrappers
• all non-trivial classes should use an opaque instance pointer (e.g., de::Socket); however, it should be noted that signals & slots require the class declaration to be in a header file
• use of libdeng2 and Qt is fully allowed on libdeng1 side in .cpp files
• use of Qt container classes vs. STL: both are allowed, however Qt containers usually have copy-on-write semantics so making read-only copies is O(1)
• all log output (previous Con_Message/Con_Printf/printf/fprintf) should use LOG_* (choose appropriate level) – the level for including messages in the log output buffer is selected with LogBuffer::enable()
• LOG_AS(“something”) can be used for setting a persistent scope prefix for subsequent messages