Commit Graph

242 Commits

Author SHA1 Message Date
Pasi Kallinen
758528f094 Grimtooth and Sunsword invoke can be paid with magic power
If the invoke timeout hasn't run out, the effect will take 25 pw,
the same as a lvl 5 spell.
If hero doesn't have that much, then the invoke fails.
2025-12-14 12:00:30 +02:00
Alex Smith
8c29b20010 Accurately track which items have been discovered, even if not #named
This fixes a couple of bugs: a long-standing bug in which writing a
scroll by label could fail even if you've already seen a scroll with
that label (due to the game not tracking whether or not you've seen a
scroll if it doesn't have a name); and a somewhat newer bug in which
spellbooks auto-identified by Wizard knowledge were marked as having
been encountered (rather than as known but not encountered).

Breaks save file compatibility, but not bones files.
2025-11-25 22:42:38 +00:00
nhmall
8d5ffbd6e3 permapoisoned follow-up
otmp can be 0 in mk_artifact. In fact, it is explicitly
being set to 0 three lines above the recently added call
to permapoisoned().

The static analyzer was griping also.
2025-06-01 22:31:09 -04:00
nhmall
a654d08c3b save/restore changes - part 3
This is the third of a series of savefile-related changes.

    This adds early-days experimental support for a completely optional
    'sfctool' utility (savefile conversion tool), to be able to export
    a savefile's contents into a more portable format. There are likely
    to be bugs at this stage. In this initial first-attempt, the export
    format is a very simple ascii output.

    NetHack can be built entirely, without also building this tool.
    NetHack has no dependencies on the tool.

    Attempts were made to minimize duplication of existing NetHack code.
    To achieve that, unfortunately, #ifdef SFCTOOL and #ifndef SFCTOOL
    had to be sprinkled around through some of the existing NetHack
    source code, so that it could be re-used for building the utility.

    The process for building the sfctool typically recompiles the source
    files with #define SFCTOOL and a distinct object file with SF- is
    produced.

sfctool notes:

    Universal ctags is used and required to produce the sfctool utility.

    Some targets were added to the Unix and Windows Makefiles to
    facilitate the build process.

         make sfctool

    That should build a copy in util.

    Note: At present, the Unix Makefiles do not copy sfctool over to the
          NetHack playground during 'make install' or 'make update'.
          Until that gets resolved by someone, The tool will
          have to be manually copied there by the builder/admin if
          desired.
          cp util/sfctool ~/nh/install/games/lib/nethackdir/sfctool

    Also, a separate Visual Studio sfctool.sln solution was written and
    placed in sys/windows/vs. That has has only very limited testing.

    Usage:

      i)  To convert an existing savefile to an exportascii format
          that co-resides with the savefile:

          sfctool -c savefile

          That *must* be executed on the same platform / architecture /
          data model that produced the save file in the first place.

     ii)  To unconvert an existing exportascii format export file to a
          historical format savefile that can then be used by NetHack:

          sfctool -u savefile

          That must be executed on the same target platform / architecture /
          data model that was used to build the NetHack that will
          utilize the save file that results.

     A Windows example:

          sfctool -c Fred.NetHack-saved-game

          That should result in creation of Fred.NetHack-saved-game.exportascii
          from existing savefile:
              %USERPROFILE%\AppData\Local\NetHack\3.7\Fred.NetHack-saved-game

     A Unix example:

          sfctool -c 1000wizard

          That should result in creation of 1000wizard.exportascii.gz
          from existing savefile in the playground save directory:
              1000wizard.gz

  Current Mechanics:
     1. Makefile recipe, or script uses universal ctags to produce
        util/sf.tags.

     2. util/sftags is built and executed to read util/sf.tags and
        generate: include/sfproto.h and src/sfdata.c.

     3. util/sfctool is built from the following:
        generated file compiled with -DSFCTOOL:
                    src/sfdata.c       -> sfdata.o
        existing files compiled with -DSFCTOOL:
                    util/sfctool.c     -> sfctool.o
                    util/sfexpasc.c    -> sfexpasc.o
                    src/alloc.c        -> sf-alloc.o
                    src/monst.c        -> sf-monst.o
                    src/objects.c      -> sf-objects.o
                    src/sfbase.c       -> sfbase.o
                    src/sfstruct.c     -> sfstruct.o
                    src/nhlua.c        -> sf-nhlua.o
                    util/panic.c       -> panic.o
                    src/date.c         -> sf-date.o
                    src/decl.c         -> sf-decl.o
                    src/artifact.c     -> sf-artifact.o
                    src/dungeon.c      -> sf-dungeon.o
                    src/end.c          -> sf-end.o
                    src/engrave.c      -> sf-engrave.o
                    src/cfgfiles.c     -> sf-cfgfiles.o
                    src/files.c        -> sf-files.o
                    src/light.c        -> sf-light.o
                    src/mdlib.c        -> sf-mdlib.o
                    src/mkmaze.c       -> sf-mkmaze.o
                    src/mkroom.c       -> sf-mkroom.o
                    src/o_init.c       -> sf-o_init.o
                    src/region.c       -> sf-region.o
                    src/restore.c      -> sf-restore.o
                    src/rumors.c       -> sf-rumors.o
                    src/sys.c          -> sf-sys.o
                    src/timeout.c      -> sf-timeout.o
                    src/track.c        -> sf-track.o
                    src/version.c      -> sf-version.o
                    src/worm.c         -> sf-worm.o
                    src/strutil.c      -> strutil.o
2025-05-25 20:38:17 -04:00
nhmall
f4a6da2e52 save/restore changes - part 2
This is the second of a series of changes related to save/restore.

    No EDITLEVEL bump has been included, because although the code
    is changed extensively by this, the content of the savefiles have
    not been changed.

    Push the use of the structlevel bwrite() and mread() function use
    out of the core and into sfstruct.c. This is groundwork for upcoming
    changes.

    In the core, replace the bwrite() and mread() calls with the
    use of type-specific savefile output (Sfo) and savefile
    input (Sfi) macros.  The macros are defined in a new header file
    savefile.h, which also contains the prototypes for the sfo_* and
    sfi_* functions that the macros ultimately expand to. The functions
    themselves are in src/sfbase.c.

    On C99, each Sfo or Sfi macro expansion refers directly to the
    corresponding  type-specific sfo_* or sfi_* function.

    If C23 or later is is use, the majority (all but 3 types) of the
    macros refer to a single _Generic output routine sfo(nhfp, dt, tag),
    and a single _Generic input routine sfi(nhfp, dt, tag), which handles
    the dispatch of the type-specific underlying functions. This was
    somewhat experimental, but turned out to be practical because the
    compiler would gripe if the type for a variable was not included in
    the _Generic when passed as an argument, so it could be fixed.

    This alters the savefile verication process by having a common set
    return values for the related functions such as uptodate(),
    check_version(), etc. The new return values return more information
    about savefile incompatibilities, beyond failure/sucess. The
    additional information will be useful for an upcoming addition.
    The expanded return values are:
     SF_UPTODATE                     (0) everything matched and looks good
     SF_OUTDATED                     (1) savefile is outdated
     SF_CRITICAL_BYTE_COUNT_MISMATCH (2) critical size count mismatch
     SF_DM_IL32LLP64_ON_ILP32LL64    (3) Windows x64 savefile on x86
     SF_DM_I32LP64_ON_ILP32LL64      (4) Unix 64 savefile on x86
     SF_DM_ILP32LL64_ON_I32LP64      (5) x86 savefile on Unix 64
     SF_DM_ILP32LL64_ON_IL32LLP64    (6) x86 savefile on Windows x64
     SF_DM_I32LP64_ON_IL32LLP64      (7) Unix 64 savefile on Windows x64
     SF_DM_IL32LLP64_ON_I32LP64      (8) Windows x64 savefile on Unix 64
     SF_DM_MISMATCH                  (9) some other mismatch
    The callers in the core have been adjusted to deal with the expanded
    return values.

    Other miscellaneous inclusions:

       - go.oracle_loc -> svo.oracle_loc.
       - add a bit (1UL << 30) to  called SFCTOOL_BIT as groundwork
         for changes to follow.
2025-05-25 15:03:13 -04:00
Pasi Kallinen
68ef0b49c1 Split arti_invoke code into smaller functions 2025-05-14 18:30:55 +03:00
nhmall
a3e12550ea savefile changes - part 1
This is the first of several savefile-related changes to
follow later. This one is groundwork for those later changes.

Remove internal compression schemes (RLECOMP and ZEROCOMP)
and discard the savefile_info struct that was primarily used to
convey which internal compression schemes had been in use.

Relocate some struct definitions into appropriate header files
for use by code to come in later changes.

Remove the two struct size-related fields from version_info and
from the nmakedefs_s. Instead, include a series of bytes near the
beginning of the savefile, representing the size of each
struct or base data type that impacts the historical savefile
content. Those are referred to as the "critical bytes".
(Related note: the "you" struct required two bytes, low and high,
due to its size).

Compare those critical bytes in a savefile against the NetHack
build that is reading the savefile. This allows mismatch detection
early in the savefile-reading process, and a clean exit, rather than
proceeding to read nonsensical values from the file. Include some
feedback on what the first mismatch was when encountering
one.

For arrays stored in the savefile, use loop-logic in the core
to write/read the array elements one at a time, rather than in
a single blob. This will be required for changes to follow later.
(impacts artiexist[], artidisco[], svd.dungeons[], svl.level_info[],
svl.level.locations[][], msrooms[] field of mapseen, svb.bases[],
svb.disco[] objects[], svm.mvitals[], svs.spl_book[], svd.doors[],
go.oracle_loc[], utrack[], wgrowtime[])

This also adds data model to the long version information.

This invalidates existing save and bones files due to the changes in
the information at the start of the file.
2025-04-15 15:35:17 -04:00
Pasi Kallinen
85de51a69a Add invocation effect to Fire and Frost Brand
Casts fireball or cone of cold at expert level
2025-04-13 13:13:54 +03:00
Pasi Kallinen
8f7258dc35 Buff Grimtooth with poison
Grimtooth is now permanently poisoned, protects the wielder from
poison, and can be invoked to throw poison.

Permapoison code comes from xNetHack by copperwater <aosdict@gmail.com>.
2025-04-12 19:24:36 +03:00
nhmall
78ca37290b cast style tidbit 2025-03-05 10:29:50 -05:00
nhmall
7ff7679a76 remove a redundant check for NULL
mksobj is declared to have a NONNULL return:
extern struct obj *mksobj(int, boolean, boolean) NONNULL;

Remove an unnecessary if block.
2025-01-27 10:12:10 -05:00
nhmall
f75e4a13b7 more follow-up for mk_artifact() 2025-01-26 21:38:37 -05:00
nhmall
ee0d955050 follow-up: make definition match proto staticfn 2025-01-26 12:25:27 -05:00
nhmall
3cca4f2707 avoid mk_artifact()-related memory leaks
Reported directly to devteam after being discovered in nerfhack.
2025-01-26 11:57:01 -05:00
Alex Smith
97e0e934e8 Use a common funcion for all monster healing
Previously, the code for monster healing was repeated every time it
was needed; this commit sends it all through a common function, which
will make it easier to make changes to how monster healing works in
the future.

This is just a code reorganisation and won't have any gameplay
effect unless I made a mistake.
2025-01-12 18:20:13 +00:00
Alex Smith
3491535548 More bugfixes for the recent artifact gifting changes 2024-12-12 07:35:50 +00:00
Alex Smith
3d8081c748 Bugfixes for the recent artifact gifting changes 2024-12-12 06:58:43 +00:00
Alex Smith
d87cadaf73 Artifact and #offer rebalance, part 1: sacrifice gifts
In 3.6, artifact gifts are often either a) entirely useless or
b) gamebreaking, neither of which is really ideal from a balance
perspective.

This commit aims to make artifact gifts more useful in the early
game by greatly increasing the chance for situational artifacts to
generate positively enchanted.  However, the most powerful
artifacts will now only be gifted if you offer a high-value corpse,
meaning that they are only likely to be accessible later in the
game.  The selection of which artifact to gift has become more
complicated in order to a) increase the chance that it fits the
character and b) reduce cheese strategies (e.g. it is no longer
possible for elves to force the gifting of Stormbringer as the
first sacrifice gift).
2024-12-12 03:14:47 +00:00
PatR
d32ab55b84 new property: BLND_RES
Add enlightenment feedback for Sunsword's blocking of becoming blind
from light flashes.  It uses an extra property so that wizard mode
can report the reason.

EDITLEVEL is being incremented, so existing save and bones files are
invalidated.
2024-11-26 20:57:11 -08:00
nhmall
bf1af7c471 Merge branch 'NetHack-3.7' of https://github.com/klorpa/NetHack into NetHack-3.7 2024-09-14 09:17:48 -04:00
PatR
50412ba53b some reformatting (1 of 4)
I recently realized that I've been editing sources in a terminal
window that was widened in order to fit curses borders for testing
something or other.  That has resulted in some new wide lines in the
source.  There were lots of old ones too.

This updates some source files to try to achieve the goal of 78
characters or less.  As in the past, I've been inconsistent about
lines with 79 characters.  Lines with 80 or more have been wrapped
or shortened (usually by trimming an end of line comment or removing
redundant parantheses, sometimes just by reducing the indentation
of the continuation portion of an already wrapped line).

I eliminated one instance of warning manipulation for non-constant
format string, and simplified stone_luck() where Ken had a silly
comment about the function argument's name.
2024-09-05 13:12:11 -07:00
klorpa
02c4147893 Typos 2024-08-31 15:28:42 -05:00
nhmall
0eb7f109e0 follow-up, program_state 2024-07-13 16:31:35 -04:00
nhmall
6c0ae092c6 distinguish global variables that get written to savefile
The g? structs had a mix of variables that were written to
the savefile, and those that were not.

For better clarity and to distinguish those that end up in
the savefile, relocate some g? variables that get written
directly to the savefile into different structs.

This updates EDITLEVEL, although technically it probably
didn't need to, since savefile contents are not changing.

Details:

    gb.bases            -> svb.bases
    gb.bbubbles         -> svb.bbubbles
    gb.branches         -> svb.branches
    gc.context          -> svc.context
    gd.disco            -> svd.disco
    gd.dndest           -> svd.dndest
    gd.doors            -> svd.doors
    gd.doors_alloc      -> svd.doors_alloc
    gd.dungeon_topology -> svd.dungeon_topology
    gd.dungeons         -> svd.dungeons
    ge.exclusion_zones  -> sve.exclusion_zones
    gh.hackpid          -> svh.hackpid
    gi.inv_pos          -> svi.inv_pos
    gk.killer           -> svk.killer
    gl.lastseentyp      -> svl.lastseentyp
    gl.level            -> svl.level
    gl.level_info       -> svl.level_info
    gm.mapseenchn       -> svm.mapseenchn
    gm.moves            -> svm.moves
    gm.mvitals          -> svm.mvitals
    gn.n_dgns           -> svn.n_dgns
    gn.n_regions        -> svn.n_regions
    gn.nroom            -> svn.nroom
    go.oracle_cnt       -> svo.oracle_cnt
    gp.pl_character     -> svp.pl_character
    gp.pl_fruit         -> svp.pl_fruit
    gp.plname           -> svp.plname
    gp.program_state    -> svp.program_state
    gq.quest_status     -> svq.quest_status
    gr.rooms            -> svr.rooms
    gs.sp_levchn        -> svs.sp_levchn
    gs.spl_book         -> svs.spl_book
    gt.timer_id         -> svt.timer_id
    gt.tune             -> svt.tune
    gu.updest           -> svu.updest
    gx.xmax             -> svx.xmax
    gx.xmin             -> svx.xmin
    gy.ymax             -> svy.ymax
    gy.ymin             -> svy.ymin

Related note:
There are some pointer variables that are heads of chains that were not
moved from 'g?' to 'sv?', because they are not actually written to the
savefile directly, but the objects/monst/trap/lightsource/timer in the
chains they point to are. That can be changed, if desired.
Examples: gi.invent, gm.migrating_objs, gb.billobjs, gm.migrating_mons,
          gf.ftrap, gl.light_base, gt.timer_base
2024-07-13 14:57:50 -04:00
SHIRAKATA Kentaro
c68f870819 split 'nothing_special' of arti_invoke() into separate function 2024-05-31 10:15:25 -07:00
PatR
6aa42750ad Sunsword vs <u.ux,u.uy>
Using #invoke on wielded or carried Sunsword and picking direction
'>' or '<' lights the hero's spot.  But setting levl[u.ux][u.uy].lit
was too simplistic.  Lighting on the Rogue Level operates on full
rooms when done inside a room and doesn't to anything with done in a
corridor.

litroom() gave inappropriate messages in a couple of special cases.
2024-05-16 13:26:46 -07:00
PatR
9d71c8e1f4 Sunsword #invoke, directed at self
Give a resistance animation if you #invoke Sunsword while it's
wielded and direct its blinding ray at yourself.  Flashing a camera
at a monster who is wielding it will also produce the animation.
2024-04-19 10:50:46 -07:00
Pasi Kallinen
969c87c0a1 Unblind telepathy range and carried artifacts 2024-04-05 09:44:52 +03:00
PatR
6aaab97044 Sunsword's #invoke for blinding ray
Support aiming at self (to become blinded) and aiming up/down (to
light the hero's current map spot only, persistently rather than
temporarily).  Also, recognize cancel at the "direction?" prompt to
not leave the #invoke cooldown count set when aborted.

Aiming at self was a little trickier than expected to test because
you're blindness-resistant when wielding Sunsword.  But it doesn't
have to be wielded to be invoked.
2024-04-02 19:56:39 -07:00
Pasi Kallinen
44575ab347 Prevent blinding ray at yourself
The code doesn't handle zapping blinding ray at yourself;
maybe it should be changed to handle it, but for now just
prevent Sunsword blinding the hero.
2024-03-31 20:24:02 +03:00
Pasi Kallinen
c71e8ec8d4 Sunsword can be invoked to create a blinding ray 2024-03-31 19:43:33 +03:00
nhkeni
22d64456a6 staticfn followup 2024-03-29 13:45:27 -04:00
nhkeni
9c0ed8ae63 NOSTATICFN for src/* 2024-03-14 17:41:51 -04:00
Erik Lunna
eb22a81088 Refactor, unify, and nerf item destruction
Note: Original change is from xNetHack by copperwater <aosdict@gmail.com>,
      but this commit comes from HACKEM-MUCHE by Erik Lunna, with
      some minor code formatting.

From xNetHack commit a0a6103bea:

'The original goal: nerf item destruction using a method I initially
 proposed for SpliceHack, in which the number of items subject to
 damage from any single source is limited by the amount of damage the
 effect caused. The intent was to be more fair all around and prevent
 aggravating situations where, for instance, a chest shock trap zaps
 you for 4 damage and immediately ten of your rings and wands blow up.

 Problem 1: no easy way to limit the items destroyed without biasing
 heavily towards the start of the invent chain. The old code was able
 to get away without bias by just indiscriminately destroying
 everything eligible with a 1/3 chance. Here, I had to introduce
 reservoir sampling in a somewhat more complex form than I've applied
 it elsewhere, since there are a pool of potential items.

 Problem 2: destroy_item no longer worked remotely like destroy_mitem,
 which still destroyed 1/3 of items indiscriminately. Commence the
 process of squishing them into one function that handles both the
 player and monsters. (Which required making a lot of adjustments to
 destroy_one_item, now named maybe_destroy_item, on nits such as
 messaging and when to negate damage. An annoying consequence of the
 merge is that in the player case, their HP is deducted and they can
 be killed directly, but for monsters they need to add up the
 destruction damage and return it.)

 Unifying destroy_item and destroy_mitem has some advantages: in
 addition to the obvious code duplication removal, it ensures monsters
 now take the same damage as players for destruction (previously they
 took a piddly 1 damage per destroyed item). Now when you hit
 something with Mjollnir and their coveted wand of death breaks apart
 and explodes, you at least get the satisfaction of knowing they took
 the standard amount of damage from it.  Monsters also now get
 symmetry with players in having extrinsic elemental resistance
 protect them from item destruction, and damage negation from item
 destruction if they were appropriately resistant.

 Problem 3: a lot of callers didn't preserve the "amount of incoming
 damage" that this refactor relies on. E.g. if the defender resisted
 that element, the local dmg variable would be set to 0. So I had to
 do some wrangling with callers to save that original damage
 value. The rule of thumb is: all *incoming* damage counts. So that
 includes the player's spellcasting bonus if applicable, but not
 things like half damage, negation due to resistance, or extra damage
 due to being vulnerable to cold/fire.

 Then I figured, while I'm here let's get rid of all those silly cases
 where destroy_items is called multiple times for various different
 object classes, and cut the object class parameter out of it. This
 has a few minor effects:

 - Places where different object classes previously rolled
   independently for destruction to happen at all now roll
   once. (Which, by my calculation, generally means less incidences of
   destruction - a fire attack now won't have three separate chances
   to hit your scrolls, potions, and spellbooks. On the flip side, a
   lucky roll will no longer save an entire object class in your
   inventory.)

 - Callers can no longer specify different probabilities for
   destroying different object classes. The only place this was really
   used was to call destroy_item with a slightly lower probability on
   SPBOOK_CLASS.  With the nerf in this commit, less of them ought to
   be destroyed anyway.

 - A very edge case of where explosion-vs-monster damage was totted up
   differently for golems, which could result in differences of a hit
   point here or there.

 - All object classes being processed in one go means that less items
   are destroyed than would be if they were still processed
   independently.  This is not really visible compared to the old
   baseline of just destroying 33% of everything, but would be a
   marked difference versus a copy of the game that still called
   destroy_items separately for different object classes. To
   compensate, I adjusted my planned damage-to-destruction-limit
   scaling factor down from 8 to 5.

 Not done: merging in ignite_items(), though that would probably be
 really easy now.'

Notes from porting from xNetHack:

- It might be necessary to reexamine at all the conditional checks for
calling destroy_items. Because item destruction is much more
restrained and uses the actual damage from an effect, we might now
need to check 'if (!rn2(3))' and similar in all the places item
destruction occurs.
2024-02-20 22:03:54 +02:00
nhmall
688ac6ffbe remove register from variable declarations 2024-02-19 16:30:07 -05:00
PatR
13ff565a67 github issue #1201 - Forcefighting webs
Issue reported by Umbire:  suggestion to always destroy adjacent webs
via 'F'<dir> if wielding Sting or Fire Brand.

Sting already did that; this adds Fire Brand.

This also augments the #untrap command when wielding either of those,
or any other blade.  And rephrases successful untrap message
"You remove {the or your} {bear trap or webbing} from Fido." to
"You extract Fido from {the or your} {bear trap or web}." since the
trap remains intact.

Forcefight and #untrap against webs ought to be reconciled to remove
[some of] their differences and/or share code.  But not by me...

Closes #1201
2024-01-21 11:58:44 -08:00
nhmall
25a8c258e6 replace x >= LOW_PM with ismnum(x) shorthand macro 2024-01-11 14:01:10 -05:00
nhmall
4e19221e55 variable 'display' causes shadow variable warnings in X11 build
display.botl      -> disp.botl
display.botlx     -> disp.botlx
display.time_botl -> disp.time_botl
2024-01-05 05:58:51 -05:00
nhmall
22e52ee905 bundle the display-related hints, that tell bot() and others
that an update is required, into a struct. Remove it from
context since there is no reason to save those.
2024-01-04 23:16:27 -05:00
nhmall
93bcfeac29 static analyzer bit for artifact.c
src/artifact.c(1589): warning C6011: Dereferencing NULL pointer 'magr'.

The 'struct monst *magr' parameter to artifact_hit() can be Null
if 'mdef' is youmonst. mdef is nonnull.
2023-12-23 22:56:21 -05:00
nhmall
516d428c40 update commented-out macro in artifact.c 2023-12-16 10:32:25 -05:00
nhmall
3eed55471b another artifact.c tweak
Use 'AFTER_LAST_ARTIFACT instead of SIZE(artilist)
2023-12-16 08:34:09 -05:00
nhmall
70dcab833d remove obj guard from stone_missile(obj) macro
Checking the callers:
toss_up() would have segfaulted prior to use of stone_missile() if obj were NULL.
thitu() now has a guard prior to use of stone_missile()
ohitmon() would have crashed from earlier dereference otmp->dknown if it were NULL,
   otmp arg is declared nonnull
thitm() now has a guard prior to use of stone_missile().
hmon_hitmon_do_hit() null obj takes a different code path than the code path
    using stone_missile(); comment asserting that added
2023-12-16 07:58:44 -05:00
nhmall
603fd18a1e update commented-out macro in artifact.c 2023-12-16 06:39:26 -05:00
nhmall
2138841e63 artifact.c tweak
get_artifact() returns the address of the existing unused first
element of artilist[] as the distinct address to check for
&artilist[ART_NONARTIFACT]
2023-12-16 06:16:51 -05:00
nhmall
6da27c7013 rework artifact.c to not use null pointers at all 2023-12-15 23:52:57 -05:00
nhmall
978ec6a3a7 augment include/extern.h with nonnull arg info
Define some macros in include/tradstdc.h, for compilers that support
__attribute__((nonnull)), to assist in identifying which parameters
on functions are not supposed to be null pointers.

Next, for the majority of functions declared in include/extern.h, this
adds the appropriate macro that matches the actual use of each function's
parameters. The additions were done after performing some analysis.

These were the rules that were followed when determining which function
parameters should be nonnul, and which are nullable:

    1. If the first use of, or reference to, the pointer parameter in the
       function is a dereference, then the parameter will be considered
       nonnull.

    2. If there is code in the function that tests for the pointer parameter
       being null, and adjusts the code-path accordingly so that no segfault
       will occur, then the parameter will not be considered nonnull (it can
       be null).

The use of the nonnull attributes allows the compiler to detect code in
callers of the function where a null parameter could get passed to the function.

If a warning is received the developer will have to do one of the following:

     - If the null being passed to the function is now appropriate,
       and the function should be able to expect a null parameter, then the
       NONNULLxxx macro will have to be removed from the function's prototype.

    or

     - If the null being passed to the function is not appropriate,
       correct the caller so it is not passing null.

    or

     - If the warning is about comparing to null, it may indicate an
       unnecessary null check in the code involved. If it is deemed to be
       unnecessary, it can then be removed.

Some static analysis tools apparently can work with the attribute, as well.

Following this, it was discovered that some functions were using one of the
(now) nonnull parameters in the first argument to the 'is_art(obj, ART)'
macro, which is defined like so:
 =>   #define is_art(o,art) ((o) && (o)->oartifact == (art))

That macro expansion inline resulted in a diagnostic warning because of the
'(o)' portion of the expanded macro, anywhere the macro was used with one of
the nonnull parameters. A test against null for a 'nonnull parameter' causes
a diagnostic warning.

To work around that, I replaced the is_art() macro with a function in
artifact.c, that accomplishes the same thing as the macro.

 =>   boolean
      is_art(struct obj *obj, int art)
      {
          if (obj && obj->oartifact == art)
              return TRUE;
          return FALSE;
      }

Some documentation...

These are the macros that have been defined for use when specifying the nonnull
parameters in a function prototype:

   ----------------------------------------------------------------------------
   |      Macro     |              Purpose                                    |
   +----------------+---------------------------------------------------------+
   | NONULL         | The function return value is never NULL.                |
   +----------------+---------------------------------------------------------+
   | NONNULLPTRS    | Every pointer argument is declared nonnull.             |
   +----------------+---------------------------------------------------------+
   | NONNULLARG1    | The 1st argument is declared nonnull.                   |
   +----------------+---------------------------------------------------------+
   | NONNULLARG2    | The 2nd argument is declared nonnull.                   |
   +----------------+---------------------------------------------------------+
   | NONNULLARG3    | The 3rd argument is declared nonnull.                   |
   +----------------+---------------------------------------------------------+
   | NONNULLARG4    | The 4th argument is declared nonnull (not used).        |
   +----------------+---------------------------------------------------------+
   | NONNULLARG5    | The 5th argument is declared nonnull.                   |
   +----------------+---------------------------------------------------------+
   | NONNULLARG7    | The 7th argument is declared nonnull (bhit).            |
   +----------------+---------------------------------------------------------+
   | NONNULLARG12   | The 1st and 2nd arguments are declared nonnull.         |
   +----------------+---------------------------------------------------------+
   | NONNULLARG13   | The 1st and 3rd arguments are declared nonnull.         |
   +----------------+---------------------------------------------------------+
   | NONNULLARG123  | The 1st, 2nd and 3rd arguments are declared nonnull.    |
   +----------------+---------------------------------------------------------+
   | NONNULLARG14   | The 1st and 4th arguments are declared nonnull.         |
   +----------------+---------------------------------------------------------+
   | NONNULLARG134  | The 1st, 3rd and 4th arguments are declared nonnull.    |
   +----------------+---------------------------------------------------------+
   | NONNULLARG17   | The 1st and 7th arguments are declared nonnull (this    |
   |                | was a special-case added for askchain(), where the      |
   |                | arguments are spread out that way. This macro           |
   |                | could be removed if the askchain arguments in the       |
   |                | prototype and callers were changed to make the          |
   |                | nonnull arguments side-by-side).                        |
   +----------------+---------------------------------------------------------+
   | NONNULLARG145  | The 1st, 4th and 5th arguments are declared nonnull     |
   |                | (this was a special-case added for find_roll_to_hit(),  |
   |                | in uhitm.c, where the arguments are spread out that way.|
   |                | We can't just use NONNULLPTRS there because the 3rd     |
   |                | argument 'weapon' can be NULL).                         |
   +----------------+---------------------------------------------------------+
   | NONNULLARG24   | The 2nd and 4th arguments are declared nonnull (this    |
   |                | was a special-case added for query_objlist()            |
   |                | in invent.c).                                           |
   +----------------+---------------------------------------------------------+
   | NONNULLARG45   | The 4th and 5th arguments are declared nonnull (this    |
   |                | was a special-case added for do_screen_description(),   |
   |                | in pager.c, where the arguments are spread out that     |
   |                | way. We can't just use NONNULLPTRS there because the    |
   |                | 6th argument can be NULL).                              |
   +----------------+---------------------------------------------------------+
   | NO_NONNULLS    | This macro expands to nothing. It is just used to       |
   |                | mark that analysis has been done on the function,       |
   |                | and concluded that none of the arguments could be       |
   |                | marked nonnull.That distinguishes a function that has   |
   |                | not been analyzed (yet), from one that has.             |
   +----------------+---------------------------------------------------------+

The NO_NONNULLS macro is meant to place a flag on the prototype to
make people aware that an assessed function was determined to not
be eligible for nonnull parameters. It expands to nothing.

Unfortunately, that macro was added partway through this exercise, so there
aren't many instances of it in the upper parts of include/extern.h, even though
the functions there were likely assessed and categorized as not having any
eligible nonnull parameters. It just never got any macro at all, in that case.

Following the parameter usage analysis that was done, the following was
noted:

       Some NetHack functions have added a test to catch a passed null
       parameter, and exit the function early as a result, or call
       impossible(), and then exit. While that approach prevents segfaults
       from dereferencing a null parameter, the early return is silent
       (when impossible is not called anyway), and the function's true
       purpose is not fulfilled. Also, the calling function may have no
       awareness that the function did not complete its intended purpose,
       in many instances.

       Functions with such a test and early return, cannot have the parameter
       declared 'nonnull', because the code to test for 'null' will cause a
       diagnostic to be issued if the parameter is nonnull.

       It might be good to revisit some of those functions and consider,
       on a case by case basis, declaring the parameter nonnull in the
       prototype, and the test/code-path commented out.
2023-12-14 20:06:03 -05:00
PatR
9ea2894448 fix discovered artifact panic
When known discoveries was displayed on a window of type NHW_MENU,
header lines sent to it via menu_add_heading() disappeared into the
bit bucket.  Switching back to putstr() made them show up.  But I also
changed the type to NHW_TEXT.  A menu_add_heading() in artifact.c was
overlooked, and after the window type change that started triggering
a panic when '\' or '`a' was used while any artifacts were discovered.

Not sure how other interfaces were dealing with this.
2023-12-08 11:41:53 -08:00
Pasi Kallinen
5dc94f3d83 Macro for picking random entry from array 2023-12-05 10:06:27 +02:00
nhmall
a7242760f7 consistent cast syntax 2023-11-13 19:28:19 -05:00