NetHack Porting Guidelines v 3.4 1999-11-29 1.0 Introduction This document goes through the steps required to port NetHack to a new machine. The basic steps in porting the program are: 1. Get the code onto your machine. The parts of the current directory setup you definitely need include src (NetHack code shared by all systems), include (include files), util (code for utility programs), and dat (various data files). The documentation in doc is strongly recommended. You already have the files in the top directory since you're reading this one. :-) A full list of the distribution files and their associated OSes may be found in the top-level file "Files". If your machine uses an OS already supported, you need the sys subdirectory for that OS and possibly sys/share. Otherwise, get the closest match (say sys/msdos for single-tasking OSes and sys/unix for multi-user OSes, along with sys/share, if nothing else comes to mind). You may want others for comparison. If your machine uses a windowing system already supported, you need the win subdirectory for that system (or the appropriate sys subdirectory if the windowing system was previously considered restricted to one OS). 2. Modify the appropriate include files to customize NetHack to your system. You may need to add a new OS-specific "*conf.h" file (see unixconf.h, pcconf.h, tosconf.h, etc. as examples). 3. If your machine uses a new OS instead of a variant of existing OSes, add a new sys subdirectory. Add, if required, a OS- specific copy of "main.c", "tty.c" and "unix.c". Possibly add an OS-specific library (see "msdos.c" and "tos.c" as examples) to provide functions NetHack wants and your OS lacks. 4. If your machine uses a new windowing system, follow doc/window.doc carefully. Put files implementing these routines in a win or sys subdirectory as appropriate. 5. If your compilation environment isn't close to one already supported, try starting from the UNIX makefiles. Modify the top level makefile and the src makefile as required. Then run an initial compile. You are bound to get some errors. You should be able to fix them in a fairly simple fashion. If things seem to be getting too complex, take a step back, and possibly send us some mail. We might be able to help. 6. Mail all of your fixes to us in a contextual form so that we can easily integrate them into the code. One general rule of thumb exists. Always add code. Don't delete somebody else's code for yours -- it won't work on their machine if you do. Always add your OS specific code inside #ifdef / #else / #endif constructs so that it will be able to be folded back into the original code easily. 2.0 Include Files 2.1 config.h The file "config.h" is a master configuration file that determines the basic features of the game, as well as many of the security options. It is intended that end users configure the game by editing "config.h" and an appropriate "*conf.h" file, so any #defines for individual preferences should be added to those files. OS-specific #defines that are not intended to be changed should also go in "*conf.h"; try to find the most appropriate place for other #defines. The following sections may require modification: - Section 1: OS and window system selection. You may have to put a #define for your OS here. If your OS is yet another UNIX variant, put the #define in unixconf.h instead. An unfortunately large amount of stuff shares this section because the #definitions have to be seen before *conf.h is reached. Don't add to this unless necessary. - Section 2: Global parameters and filenames. These will have to be customized to your system. - Section 3: Type definitions and other compiler behavior. These will have to be matched to your compiler. 2.2 global.h This file defines things specific to NetHack that should not require modification by an end user. For a new port, you may have to add automatic inclusion of another auxiliary config file (*conf.h) which you wrote for your system. 2.3 extern.h If you create any new source modules or new functions in old modules, you must enter the names of the new external references (the functions defined there for external use) in this file. 2.4 system.h This file contains references for all hooks into the OS (via the standard "C" libraries). Depending on what your standard library looks like, you may have to put new entries into this file. 3.0 Source files The first step in getting the game up is to get the "makedefs" program running. This program is used to create configuration-specific files for the game. Once "makedefs" has been built, the rest of the game can be compiled. You may have to create an OS-specific module to handle things you want to use, like a mouse or a ram-disk. The utility compilers "dgn_comp" and "lev_comp" may be a better place to start. They also require "makedefs" but are independent of "nethack". They are usually the last programs made, but since they are much smaller they may be more tractable when first arguing with the include files. These programs create binary data files that "nethack" uses to guide its dungeon creation. 3.1 Makefiles This distribution provides makefiles for several kinds of systems. There are joint makefiles for the various varieties of UNIX, makefiles for MSDOS, a makefile for NT, and so on. You may have to create a new makefile for your specific machine. You may even have to translate some makefiles into a form more congenial to your system. If possible, however, add to one of those provided. 3.2 termcap.c If your system wants to use tty windowing and it doesn't run off of a termcap or terminfo database, you may have to put the appropriate terminal control strings into termcap.c. This has already been done for MSDOS, and these mods can be used as an example. You can also consider using the termcap code from sys/share/tclib.c or sys/share/termcap.uu, especially if your system supports multiple kinds of terminals. 3.3 main.c You may need to create a new "main.c" module. If you do, call it [OS]main.c where the [OS] is replaced with the name of the OS you are porting to. This file contains the mainline module, which reads options from the command line (or wherever) and processes them. It also contains various functions associated with game startup. 3.4 tty.c You may need to create a new "tty.c" module. If you do, call it [OS]tty.c where the [OS] is replaced with the name of the OS you are porting to. This file contains the routines that configure the terminal/console for raw I/O, etc. 3.5 unix.c You may need to create a new "unix.c" module. If you do, call it [OS]unix.c where the [OS] is replaced with the name of the OS you are porting to. This file contains some OS dependencies concerning time and filename creation. An object of the NetHack development project is to get the game working on as many different types of hardware and under as many different operating systems as is practical. Any assistance will be appreciated.