$ show HerculesWS/Hercules
Hercules is a C-based MMORPG server emulator for Ragnarok Online. It is a multi-process application suite: the login server handles account authentication and IP banning, the char server manages persistent character data, guilds, mail, pets, homunculi, and other account-wide state, the map server runs the real-time game world with combat, NPC scripting, instances, battlegrounds, item systems, and chat, and the API server exposes HTTP endpoints for external tools. All servers persist to MySQL/MariaDB through a shared SQL abstraction and communicate using custom binary inter-server packets. The architecture is modular at the subsystem level through interface structs containing function pointers, which also power a runtime plugin system (HPM). The primary data flow is: client packets arrive at login/char/map servers; map servers mutate real-time game state and delegate persistence to the char server; the char server executes SQL against the database; the API server proxies selected requests through login/char connections. External dependencies include MariaDB/MySQL, libconfig, cJSON, zlib, PCRE, GRF archive files, and bundled HTTP/multipart parsers. The codebase is actively maintained with CI covering GCC, Clang, MSVC, sanitizers, and multiple database backends, and it has recently transitioned toward CMake and Conan. However, it retains significant legacy weight: extensive PACKETVER conditionals, autogenerated packet header files, bundled third-party libraries, monolithic source files, and historical SQL migrations. It is a specialized game-server project rather than a general-purpose library, but several low-level infrastructure components are cleanly separated and reusable.
The LLM identified 5 files worth highlighting for reuse:
A generic timer facility built on a binary heap, supporting one-shot and interval timers with efficient scheduling. It is isolated from game logic and can be extracted into any C event-driven server needing timer management.
Entry Reuse System: a fixed-size object allocator that recycles entries to reduce allocation churn and memory fragmentation. The pattern is self-contained and valuable for high-throughput servers or libraries that repeatedly allocate small structs.
A thin SQL interface used uniformly across all server processes, encapsulating connections, queries, and prepared statements behind a C struct. It demonstrates a clean persistence abstraction and could be adapted for other C projects that need database backend portability.
Grid-based pathfinding using A* with heuristics and distance functions. Although embedded in the map server, the algorithm is separated enough to be lifted into tile-based games or robotics/grid navigation projects requiring deterministic movement.
A standalone pure-Python parser for libconfig-formatted configuration files, including include directive resolution and attribute-style object access. It is directly reusable in any Python toolchain that must read libconfig files without native bindings.