X-Git-Url: https://jxself.org/git/?p=open-adventure.git;a=blobdiff_plain;f=notes.adoc;h=6ee80a5a463cc51799207b2295d0f92c671f98f4;hp=9981a127fe61998a915a16094378fc92e408c1b0;hb=HEAD;hpb=df87c596fb94eed31616a827289b1a30fe83cf87 diff --git a/notes.adoc b/notes.adoc index 9981a12..b970e7c 100644 --- a/notes.adoc +++ b/notes.adoc @@ -1,5 +1,7 @@ = Open Adventure Maintainer's Notes = by Eric S. Raymond +// SPDX-FileCopyrightText: (C) Eric S. Raymond +// SPDX-License-Identifier: CC-BY-4.0 In which we explain what has been done to this code since Don Woods authorized us to ship it under an open-source license. There's a @@ -11,8 +13,11 @@ The principal maintainers of this code are Eric S. Raymond and Jason Ninneman. Eric received Don Woods's encouragement to update and ship the game; Jason signed on early in the process to help. The assistance of Peje Nilsson in restructuring some particularly grotty gotos is -gratefully acknowledged. Petr Voropaev contributed fuzz testing. Aaron -Traas did a lot of painstaking work to improve test coverage. +gratefully acknowledged. Petr Voropaev contributed fuzz testing and +code cleanups. Aaron Traas did a lot of painstaking work to improve +test coverage, and factored out the last handful of gotos. Ryan +Sarson nudged us into fixing a longstannding minor bug in the +handling of incorrect magic-word sequebcesm, == Nomenclature == @@ -40,26 +45,43 @@ form that is (a) readable, and (b) friendly to forward translation to future languages. It has already survived a move from FORTRAN to C; a future as a Python or Go translation seems possible, even probable. +Compatibility with the 2.5 source we found has been checked by +building a version patched minimally to support the seed command and +running it against the entire test suite, which has 100% code +coverage. + == Functional changes == Bug fixes: +* The caged bird used to be counted as two items in your inventory. + * Reading the relocated Witt's End sign in the endgame didn't work right. -* Behavior when saying the giant's magic words outside his room wasn't - quite correct - the game responded as though the player were in - the room. - -* Attempting to extinguish an unlit urn caused it to lose its oil. +* Oyster was readable after first gotten even when not carried. + +* Response to an attempt to unlock the oyster while carrying it was incorrect. + +* Behavior when saying the giant's magic words before having seen them + wasn't quite correct - the game responded as though the player had + already read them ("...can't you read?"). The new message is "Well, + that was remarkably pointless!" The -o option reverts this change. -* Unrecognized words are no longer truncated to 5 characters and - uppercased when they are echoed. (This behavior is restored by the - oldstyle switch.) +* Attempting to extinguish an unlit urn caused it to lose its oil. * "A crystal bridge now spans the fissure." (progressive present) was incorrect most places it appeared and has been replaced by "A crystal bridge spans the fissure." (timeless present). +* A few minor typos have been corrected: absence of capitalization on + "Swiss" and "Persian", inconsistent spelling of "imbedded" vs. "embedded", + "eying" for "eyeing", "thresholds" for "threshholds". + +* Under odd circumstances (dropping rug or vase outdoors) the game could + formerly say "floor" when it should say "ground" (or "dirt", or something). + +Enhancements: + By default, advent issues "> " as a command prompt. This feature became common in many variants after the original 350-point version, but was never backported into Crowther & Woods's main line before now. @@ -71,11 +93,19 @@ for a turn, 'i' for 'inventory', 'g' for 'get', and 'd' for 'drop'. The 'd' alias collides with 'd' for 'down', but the others have been implemented. The "-o" (oldstyle) option disables them. +Unrecognized words are no longer truncated to 5 characters and +uppercased when they are echoed. The "-o" (oldstyle) option restores +this behavior. + A "seed" command has been added. This is not intended for human use but as a way for game logs to set the PRNG (pseudorandom-number generator) so that random events (dwarf & pirate appearances, the bird's magic word) will be reproducible. +A "version" command has been added. This has no effect on gameplay. + +The text displayed by the "news" command has been updated. + A -l command-line option has been added. When this is given (with a file path argument) each command entered will be logged to the specified file. Additionally, a generated "seed" command will be put @@ -97,10 +127,27 @@ FORTRAN-derived code that formerly implemented the save/restore functions; without C's fread(3)/fwrite() and structs it was necessarily pretty ugly by modern standards. Encryption and checksumming have been discarded - it's pointless to try -tamper-proofing saves when everyone has the source code. +tamper-proofing saves when everyone has the source code. However +the game still integrity-checks savefiles on resume, including an +abort if the endianness of the restoring machine does not match that of +the saving machine. There is a magic-cookie header on the saves so +in theory they could be identified by programs like file(1). + +Save and resume filenames are stripped of leading and trailing +whitespace before processing. + +A -r command-line option has been added. When it is given (with a file +path argument) it is functionally equivalent to a RESTORE command. + +An -a command-line option has been added (conditionally on +ADVENT_AUTOSAVE) for use in BBS door systems. When this option is +given, the game roads from the specified filename argument on startup +and saves to it on quit or a received signal. There is a new nmessage +to inform the user about this. -A -r command-line been added. When it is given (with a file path -argument) it is functionally equivalent to a RESTORE command. +The game can be built in a mode that entirely disables save/resume +(-DADVENT_NOSAVE). If the game had been built this way, a diagnostic is +emitted if you try to save or resume. == Translation == @@ -111,8 +158,7 @@ ugly and quite unreadable. Jason Ninneman and I have moved it to what is almost, but not quite, idiomatic modern C. We refactored the right way, checking correctness against a comprehensive test suite that we built first and verified -with coverage tools (we have over 95% coverage, with the remaining -confined to exception cases that are very difficult to reach). This is +with coverage tools (there is effectively 100% code coverage). This is what you are running when you do "make check". The move to modern C entailed some structural changes. The most @@ -124,7 +170,7 @@ The original code was greatly complicated by a kind of bit-packing that was performed because the FORTRAN it was written in had no string type. Text from the adventure.text file was compiled into sequences of sixbit code points in a restricted character set, packed 5 to a -32-bit word (it seems clear from the code that words were originally +32-bit word (and it seems clear from the code that words were originally *6* chars each packed into a PDP-10 36-bit word). A command noun or verb was one of these words, and what would be string operations in a more recent language were all done on sequences of these words. @@ -139,6 +185,9 @@ afl (American Fuzzy Lop). We've found and fixed some crashers in our new code (which occasionally uses malloc(3)), but none as yet in Don's old code (which didn't). +After version 1.11, correctness was carefully checked against the +behavior of a binary from before the big refactoring. + The code falls short of being fully modern C in the following ways: @@ -148,10 +197,6 @@ ways: and the choice to refrain will make forward translation into future languages easier. -* There are a few gotos left that resist restructuring; all are in the - principal command interpreter function implementing its state - machine. - * Linked lists (for objects at a location) are implemented using an array of link indices. This is a surviving FORTRANism that is quite unlike normal practice in C or any more modern language. We have not tried @@ -162,14 +207,18 @@ ways: arrays are a cell larger than they strictly need to be and cell 0 is unused. -* The code is still mostly typeless, slinging around machine longs - like a FORTRAN or BCPL program. Some (incomplete) effort has been made - to introduce semantic types. - We have made exactly one minor architectural change. In addition to the old code's per-object state-description messages, we now have a per-object message series for state *changes*. This makes it possible to pull a fair amount of text out of the arbitrary-messages list and associate those -mesages with the objects that conceptually own them. +messages with the objects that conceptually own them. + +== Development status == + +We consider this project finished. All issues and TODOs have been +cleared, behavior has been carefully checked against original ADVENT, +no future demand for new features is expected, and the test suite has +100% code coverage. If new bugs appear as the toolchain bit-rots out +from under underneath, we will fix those problems. // end