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SF_OUTDATED (1) savefile is outdated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.
We've had reports of a couple of issues building against musl libc.
Issues reported:
- build procedures utilize cat for Guidebook-creation, and cat
is deprecated in distros that use musl libc.
- some of the CRASHREPORT code is using library functions that
are not available in the musl libc environment. The reported
functions were backtrace() and backtrace_symbols(), which use
header file /usr/include/execinfo.h.
So we'll try to accommodate this. Since we don't have a means of
autodetecting the musl libc situation during the build (as of yet), the
builder will have to specify 'make musl=1' on the make command line.
Specifying 'musl=1' on the make command line will:
1. ensure that NOCRASHREPORT gets defined in the C preprocessor.
2. set COLCMD to be '../util/stripbs' instead of 'col -bx'.
Closes#1393
Define a macro NH_C to provide a shorter & simpler way to test for
which C standard the build is being carried out under (c99 or c23).
NH_C > 202300L Being compiled under C23 or greater
NH_C > 199900L Being compiled under C99 or greater
NH_C > 198900L Being compiled under C89 or greater,
or C std could not be determined.
While NetHack only requires c99, we've been taking advantage
of some c23 features (attributes), if they are available,
to allow the use of ATTRNORETURN/NORETURN and FALLTHROUGH on
compilers other than gcc.
Also add some comment documentation to tradstdc.h about NetHack's
use of c99.
The sys/unix/Makefile.top change overcomes a warning in the
Makefile-generated nhlua.h. That warning arises under some compilers
that rely on attribute [[noreturn]] ahead of a declaration
(NetHack macro ATTRNORETURN), rather than the trailing gcc
__attribute((noreturn)) (NetHack macro NORETURN). The sed command
is modified to include ATTRNORETURN at the start of the declaration
in addition to the NORETURN at the end of the declaration, in the
generated file. That's the same combination that's used for the
declaration of other functions that don't return.
Even though most of these are cast to void (but not all), the
mips cross-compiler seems determined to warn about them anyway.
Suppress that particular warning altogether to quiet the build.
That is not the ideal approach, but if the normal way of whitelisting
individual cases isn't working, I'm not sure of another course of
action.
Add a note about NO_TERMS to include/wintty.h for clarity.
Rename tty_startup and tty_shutdown to term_startup() and
term_shutdown(). They are found in termcap.c for !NO_TERMS
like most of the other term_ routines, as well as having
versions for several of the NO_TERMS platforms. They aren't
part of the tty_interface called from the core. The tty
implementation does call and rely on them.
Remove some conditional #ifdef's around term_shutdown()
(formerly tty_shutdown()) and just ensure that all the
tty platforms have an implementation that they can link
with, even if it is just a stub presently.
Put the protype for nethack_exit in extern.h to reduce
maintenance to a single spot, and remove it from other
locations. A warning in the msdos cross-compile led to
this change.
Instead of flat, have bin, lib and include folders for
the native DOS pieces.
If you have been cross-compiling for MSDOS, you will
need to carry out the following to bring things up-to-date:
sys/msdos/fetch-cross-compiler.sh
make CROSS_TO_MSDOS=1 WANT_DEBUG=1 package
This helps avoid a potential chicken-and-egg scenario
with the system configuration file (sysconf).
If sysconf wasn't accessible at the expected location, it
caused an immediate exit, without relaying any helpful
information. That happened even when using:
'nethack --showpaths'
That's particularly unhelpful, because the --showpaths
output might have been useful towards understanding where
NetHack was looking for such things.
That left you without an easy recourse to identify where
the game is looking for the sysconf file. That might be
especially troublesome if you didn't build the game
yourself.
There was a transcription error in the comments in cstd.h for
the standard list of header files, where only the description
remained for <stdlib.h>, not the name of the file itself.
Remove several extraneous inclusions of the standard C99 headers.
Tested on the following afterwards:
Linux (using hints/linux.370) including tty, curses, qt6, and X11
macOS (using hints/macOS.370) including tty, curses, qt5, and X11
Windows MSYS2 using sys/windows/GNUmakefile
Windows Visual Studio using sys/windows/Makefile.nmake
msdos cross-compile on Ubuntu using djgpp cross-compiler
This build command will include line number info, gdb.exe or nhgdb.bat in the package:
make CROSS_TO_MSDOS=1 WANT_DEBUG=1 package
This build command will not include line number info, gdb.exe or nhgdb.bat in the package:
make CROSS_TO_MSDOS=1 package
The WANT_DEBUG=1 will cause the cross-compile to include line
number information in the NetHack executable, useful for
backtraces and gdb debugging sessions.
How a developer can use the optional deploy-to-dosbox target:
make CROSS_TO_MSDOS=1 WANT_DEBUG=1 dosbox=/mnt/c/dosbox deploy-to-dosbox
where dosbox= points to the directory which will be mounted for
your drive in dosbox
THe deploy-to-dosbox recipe ensures that a target copy of gdb.exe
ends up alongside nethack.exe at the target, including:
- placing the source code that gdb requires on the target
in the nhsrc subfolder.
- an nhgdb.bat that supplies the right switches to gdb
for locating the NetHack sources.
gcc has recognized various "magic comments" for white-listing
occurrences of implicit fallthrough in switch statements for
a long time:
The range and shape of "falls through" comments accepted are
contingent upon the level of the warning. (The default level is =3.)
-Wimplicit-fallthrough=0 disables the warning altogether.
-Wimplicit-fallthrough=1 treats any kind of comment as a "falls through" comment.
-Wimplicit-fallthrough=2 essentially accepts any comment that contains something
that matches (case insensitively) "falls?[ \t-]*thr(ough|u)" regular expression.
-Wimplicit-fallthrough=3 case sensitively matches a wide range of regular
expressions, listed in the GCC manual. E.g., all of these are accepted:
/* Falls through. */
/* fall-thru */
/* Else falls through. */
/* FALLTHRU */
/* ... falls through ... */
etc.
-Wimplicit-fallthrough=4 also, case sensitively matches a range of regular
expressions but is much more strict than level =3.
-Wimplicit-fallthrough=5 doesn't recognize any comments.
Plenty of other compilers did not recognize the gcc comment convention,
and up until now the compiler warning for detecting unintended
fallthrough had to be suppressed on other compilers. That's because the code
in NetHack has been relying on the gcc approach, and only the gcc approach.
The C23 standard introduces an attribute [[fallthrough]] for the
functionality, when implicit fallthrough warnings have been enabled.
Several popular compilers already support that, or a very similar attribute
style approach, today, even ahead of their C23 support:
C compiler whitelist approach
--------------------------- -------------------------------------
C23 conforming compilers [[fallthrough]]
clang versions supporting
standards prior to
C23 __attribute__((__fallthrough__))
Microsoft Visual Studio
since VS 2022 17.4.
The warning C5262 controls
whether the implict
fallthrough is detected and
warned about with
/std:clatest. [[fallthrough]]
This adds support to NetHack for the attribute approach by inserting a
macro FALLTHROUGH to the existing cases that require white-listing, so
other compilers can analyze things too.
The definition of the FALLTHROUGH macro is controlled in include/tradstdc.h.
The gcc comment approach has also been left in place at this time.
In case someone switches from NetHack-3.6 to NetHack-3.7 and does
'make spotless' after the switch instead of before, get rid of out
of date lev_comp and dgn_comp.
...some of them, at any rate. We shut off (1) warnings provoked by Matt
Bishop's "mn" macro package, and (2) warnings spuriously emitted by
groff 1.23 and previous when "-wall" (or "-ww") is specified.
Also update explanatory comments.
