I got one intermittent regression test failure due to 'argument
list too long' on a Debian x86_64 system.
src/cmd/ksh93/sh/path.c: path_xargs():
- Leave extra argument space for systems that need extra bytes:
1KiB per extra byte, with a minimum of 2KiB (the old value).
This fixes the function that sets ${.sh.match}. Patch from OpenSUSE:
https://build.opensuse.org/package/view_file/shells/ksh/ksh93-limit-name-len.dif
src/cmd/ksh93/sh/init.c: sh_setmatch():
- Fix node size calculation, possibly preventing data corruption.
src/cmd/ksh93/include/ulimit.h: Limit_t:
- Defining the 'name' struct member as 'char name[16]' makes
no sense as the name is being initialised statically in
data/limits.c; just make it a 'char *name' pointer.
This fixes the following regressions marked TODO in attributes.sh:
$ typeset -L 13 bar; readonly bar; typeset -p bar
typeset -r -L 0 foo # exp.: typeset -r -L 13 foo
$ typeset -R 13 bar; readonly bar; typeset -p bar
typeset -r -R 0 bar # exp.: typeset -r -R 13 bar
$ typeset -Z 13 baz; readonly baz; typeset -p baz
typeset -r -Z 0 -R 0 baz # exp.: typeset -r Z 13 -R 13 baz
I've discovered that these were briefly fixed between fdb9781e (Red
Hat patch for typeset -xu/-xl) and 95fe07d8 (reversal of patch,
different -xu/-xl fix, but reintroduced these regressions).
src/cmd/ksh93/sh/name.c: nv_newattr():
- Replace check from 95fe07d8 with a new one that combines its
approach with that of fdb9781e: do not change size (and hence
return early) if NV_RDONLY and/or NV_EXPORT are the only
attributes that are changing.
src/cmd/ksh93/tests/attributes.sh:
- Enable the TODO regression tests.
This fixes part of https://github.com/ksh93/ksh/issues/87:
Scalar arrays (-a) and associative arrays (-A) of a type created by
'enum' did not consistently block values not specified by the enum
type, yielding corrupted results.
An expansion of type "${array[@]}" yielded random numbers instead
of values for associative arrays of a type created by 'enum'.
This does not yet fix another problem: ${array[@]} does not yield
all values for associative enum arrays.
src/cmd/ksh93/bltins/enum.c: put_enum():
- Always throw an error if the value is not in the list of possible
values for an enum type. Remove incorrect check for the NV_NOFREE
flag. Whatever that was meant to accomplish, I've no idea.
src/cmd/ksh93/sh/array.c: nv_arraysettype():
- Instead of sh_eval()ing a shell assignment, use nv_putval()
directly. Also use the stack (see src/lib/libast/man/stk.3)
instead of malloc to save the value; it's faster and will be
auto-freed at some point. This shortens the function and makes it
faster by not entering into a whole new shell context -- which
also fixes another problem: the error message from put_enum()
didn't cause the shell to exit for indexed enum arrays.
src/cmd/ksh93/sh/name.c: nv_setlist():
- Apply a patch from David Korn that correctly sets the data type
for associative arrays, fixing the ${array[@]} expansion yielding
random numbers. Thanks to @JohnoKing for the pointer.
https://github.com/ksh93/ksh/issues/87#issuecomment-662613887https://www.mail-archive.com/ast-developers@lists.research.att.com/msg00697.html
src/cmd/ksh93/tests/enum.sh:
- Add tests checking that invalid values are correctly blocked for
indexed and associative arrays of an enum type.
Makes progress on: https://github.com/ksh93/ksh/issues/87
Turns out the assumption I was operating on, that Linux and macOS
align arguments on 32 or 64 bit boundaries, is incorrect -- they
just need some extra bytes per argument. So we can use a bit more
of the arguments buffer on these systems than I thought.
src/cmd/ksh93/features/externs:
- Change the feature test to simply detect the # of extra bytes per
argument needed. On *BSD and commercial Unices, ARG_EXTRA_BYTES
shows as zero; on Linux and macOS (64-bit), this yields 8. On
Linux (32-bit), this yields 4.
src/cmd/ksh93/sh/path.c: path_xargs():
- Do not try to calculate alignment, just add ARG_EXTRA_BYTES to
each argument.
- Also add this when substracting the length of environment
variables and leading and trailing static command arguments.
src/cmd/ksh93/tests/path.sh:
- Test command -v/-V with -x.
- Add a robust regression test for command -x.
src/cmd/ksh93/data/builtins.c, src/cmd/ksh93/sh.1:
- Tweak docs. Glob patterns also expand to multiple words.
This takes another small step towards disentangling the build
system from the old AT&T environment. The USAGE_LICENSE macros with
author and copyright information, which was formerly generated
dynamically for each file from a database, are eliminated and the
copyright/author information is instead inserted into the AST
getopt usage strings directly.
Repetitive license/copyright information is also removed from the
getopt strings in the builtin commands (src/lib/libcmd/*.c and
src/cmd/ksh93/data/builtins.c). There's no need to include 55
identical license/copyright strings in the ksh binary; one (in the
main ksh getopt string, shown by ksh --man) ought to be enough!
This makes the ksh binary about 10k smaller.
It does mean that something like 'enum --author', 'typeset
--license' or 'shift --copyright' will now not show those notices
for those builtins, but I doubt anyone will care.
This commit fixes 'command -x' to adapt to OS limitations with
regards to data alignment in the arguments list. A feature test is
added that detects if the OS aligns the argument on 32-bit or
64-bit boundaries or not at all, allowing 'command -x' to avoid
E2BIG errors while maximising efficiency.
Also, as of now, 'command -x' is a way to bypass built-ins and
run/query an external command. Built-ins do not limit the length of
their argument list, so '-x' never made sense to use for them. And
because '-x' hangs on Linux and macOS on every ksh93 release
version to date (see acf84e96), few use it, so there is little
reason not to make this change.
Finally, this fixes a longstanding bug that caused the minimum exit
status of 'command -x' to be 1 if a command with many arguments was
divided into several command invocations. This is done by replacing
broken flaggery with a new SH_XARG state flag bit.
src/cmd/ksh93/features/externs:
- Add new C feature test detecting byte alignment in args list.
The test writes a #define ARG_ALIGN_BYTES with the amount of
bytes the OS aligns arguments to, or zero for no alignment.
src/cmd/ksh93/include/defs.h:
- Add new SH_XARG state bit indicating 'command -x' is active.
src/cmd/ksh93/sh/path.c: path_xargs():
- Leave extra 2k in the args buffer instead of 1k, just to be sure;
some commands add large environment variables these days.
- Fix a bug in subtracting the length of existing arguments and
environment variables. 'size -= strlen(cp)-1;' subtracts one less
than the size of cp, which makes no sense; what is necessary is
to substract the length plus one to account for the terminating
zero byte, i.e.: 'size -= strlen(cp)+1'.
- Use the ARG_ALIGN_BYTES feature test result to match the OS's
data alignment requirements.
- path_spawn(): E2BIG: Change to checking SH_XARG state bit.
src/cmd/ksh93/bltins/whence.c: b_command():
- Allow combining -x with -p, -v and -V with the expected results
by setting P_FLAG to act like 'whence -p'. E.g., as of now,
command -xv printf
is equivalent to
whence -p printf
but note that 'whence' has no equivalent of 'command -pvx printf'
which searches $(getconf PATH) for a command.
- When -x will run a command, now set the new SH_XARG state flag.
src/cmd/ksh93/sh/xec.c: sh_exec():
- Change to using the new SH_XARG state bit.
- Skip the check for built-ins if SH_XARG is active, so that
'command -x' now always runs an external command.
src/lib/libcmd/date.c, src/lib/libcmd/uname.c:
- These path-bound builtins sometimes need to run the external
system command by the same name, but they did that by hardcoding
an unportable direct path. Now that 'command -x' runs an external
command, change this to using 'command -px' to guarantee using
the known-good external system utility in the default PATH.
- In date.c, fix the format string passed to 'command -px date'
when setting the date; it was only compatible with BSD systems.
Use the POSIX variant on non-BSD systems.
Three OpenSUSE patches from:
https://build.opensuse.org/package/show/shells/ksh
As usual, the relevant bug is not currently public:
https://bugzilla.opensuse.org/show_bug.cgi?id=844071
src/cmd/ksh93/sh/xec.c: sh_debug()/sh_exec():
- Fix stk restoration. [bnc#844071]
src/lib/libast/misc/stk.c:
- Fix stk aliasing code. [bnc#844071]
(ksh93-stkalias.dif)
- Make a unknown location fatal in stkset() so that we get a core
dump right away instead of later in an unrelated part of code.
(ksh93-stkset-abort.dif)
src/lib/libast/man/stk.3,
src/lib/libast/man/stak.3:
- Update manual with new stkset() behaviour. (93u+m addition)
(Note that stak is implemented as macros that translate to stk)
This backports most of the Cdt (container data types) mechanism
from the ksh 93v- beta, based on ground work done by OpenSUSE:
https://build.opensuse.org/package/view_file/shells/ksh/ksh93-dttree-crash.dif
plus adaptations to match ksh 93u+m and an updated manual page
(src/lib/libast/man/cdt.3) added directly from the 93v- sources.
| Thu Dec 20 12:48:02 UTC 2012 - werner@suse.de
|
| - Add ksh93-dttree-crash.dif - Allow empty strings in (dt)trees
| (bnc#795324)
|
| Fri Oct 25 14:07:57 UTC 2013 - werner@suse.de
|
| - Rework patch ksh93-dttree-crash.dif
As usual, precious little information is available because the
OpenSUSE bug report is currently closed to the public:
https://bugzilla.opensuse.org/show_bug.cgi?id=795324
However, a cursory inspection suggests that this code contains
improvements to do with concurrent processing and related
robustness. The new cdt.3 manual page adds a lot about that.
This has been in production use on OpenSUSE for a long time,
so hopefully this will make ksh a little more stable again.
Only one way to find out: let's commit and test this...
BTW, to get a nice manual, use groff and ghostscript's ps2pdf:
$ groff -tman src/lib/libast/man/cdt.3 | ps2pdf - cdt.3.pdf
An unquoted variable expansion evaluated in a DEBUG trap action
caused IFS field splitting to be deactivated in code executed after
the trap action. Thanks to Koichi Nakashima for the reproducer:
| v=''
| trap ': $v' DEBUG
| A="a b c"
| set -- $A
| printf '%s\n' "$@"
|
| Expected
|
| a
| b
| c
|
| Actual
|
| a b c
src/cmd/ksh93/sh/fault.c: sh_trap():
- Remove incorrect save/restore of sh.ifstable, the internal state
table for field splitting. This reverts three lines added in ksh
93t+ 2009-11-30. Analysis: As an expansion is split into fields
(macro.c, lines 2367-2471), sh.ifstable is modified. If that
happens within a DEBUG trap, any modifications in ifstable are
undone by the restoring memccpy, leaving an inconsistent state.
src/cmd/ksh93/COMPATIBILITY:
- Document the DEBUG trap fixes, particularly the incorrect
inheritance by subshells and functions that some scripts may now
rely on because this bug is so longstanding. (re: 2a835a2d)
src/cmd/ksh93/tests/basic.sh:
- Add relevant tests.
Resolves: https://github.com/ksh93/ksh/issues/155
TODO: add a -T (-o functrace) option as in bash, which should allow
subshells and ksh-style functions to inherit DEBUG traps.
P.S.: The very handy multishell repo allows us to use 'git blame'
to trace the origin of the recently fixed DEBUG trap bugs.
The off-by-one error causing various bugs, reverted in 2a835a2d,
was introduced in ksh 93t 2008-07-25:
https://github.com/multishell/ksh93/commit/8e947ccf
(fault.c, line 321)
The incorrect check causing the exit status bug, reverted in
d00b4b39, was introduced in ksh 93t 2008-11-04:
https://github.com/multishell/ksh93/commit/b1ade268
(fault.c, line 459)
The ifstable save/restore causing the field splitting bug, reverted
in this commit, was introduced in ksh 93t+ 2009-11-30:
https://github.com/multishell/ksh93/commit/53d9f009
(fault.c, lines 440, 444, 482)
So all the bugs reported in #155 were fixed by simply reverting
these specific changes. I think that they are some experiments that
the developers simply forgot to remove. I've suspected such a thing
multiple times before. ksh93 was developed by researchers who were
genius innovators, but incredibly sloppy maintainers.
This trap failed to be restored correctly when being trapped in
a subshell, causing corruption or a crash when restoring the
parent shell environment's trap upon leaving the subshell.
Thanks to Koichi Nakashima for the report and reproducer.
src/cmd/ksh93/sh/fault.c: sh_sigreset():
- Fix an off-by-one error in the loop that restores the
pseudosignal traps.
src/cmd/ksh93/tests/basic.sh:
- Test overwriting the main shell trap in a subshell for all
pseudosignals.
Makes progress on: https://github.com/ksh93/ksh/issues/155
UnixWare's ps prefers to read psinfo (from the proc structure in
kernel memory) within /proc as an anti-Trojan horse measure.
Updates to argv[0] are still reflected within /proc/$pid/cmdline,
which is useful for diagnostic purposes.
src/cmd/ksh93/sh/main.c:
- Remove __USLC__ from the list of platforms excluded from the
fixargs method.
src/cmd/ksh93/tests/basic.sh:
- Read /proc/$pid/cmdline instead of ps on UnixWare.
SHOPT_KIA enables the -R option that generates a cross-reference
database from a script. However, no tool to analyse this database
is shipped or seems to be available anywhere (in spite of multiple
people looking for one), and the format is very opaque. No usage
examples are known or findable on the internet. This seems like it
should not be compiled in by default, although we'll keep the code
in case some way to use it is found.
src/cmd/ksh93/SHOPT.sh:
- Disable SHOPT_KIA by default by removing the default 1 value.
src/cmd/ksh93/sh/args.c, src/cmd/ksh93/sh/parse.c:
- Fix a couple of preprocessor logic bugs that made it impossible
to compile ksh without SHOPT_KIA.
src/cmd/ksh93/data/builtins.c:
- Fix typo in -R doc in ksh --man (in case SHOPT_KIA is enabled).
src/cmd/ksh93/sh.1:
- Since sh.1 is not generated dynamically, remove the -R doc.
What is this for? See cefe087d
src/cmd/ksh93/Mamfile:
- Make iffe generate a test for the presence of setproctitle(3).
src/cmd/ksh93/sh/main.c:
- Include setproctitle test result.
- Re-enable fixargs() for FreeBSD and DragonFly BSD.
Disable it for UnixWare.
- fixargs(): Add _lib_setproctitle version. Keep it simple with a
128-character buffer array -- should be plenty for 'ps' output.
- fixargs(): Fix an off-by-one in zeroing the rest of the buffer.
src/cmd/ksh93/tests/basic.sh:
- Update the relevant regression test to run on FreeBSD/DragonFly
and tolerate the "ksh: " prefix added by setproctitle(3).
src/cmd/ksh93/include/version.h:
- Centrally define the 93u+m copyright (SH_RELEASE_CPYR) for adding
to the original AT&T copyright in 'ksh --man' and 'shcomp --man'.
- Centrally define the binary header version number for bytecode
generated by shcomp: SHCOMP_HDR_VERSION.
- Bump SHCOMP_HDR_VERSION from 3 to 4. Converting all the preset
aliases to builtin commands has caused new bytecode to be
incompatible with old ksh. (However, old bytecode runs fine on
93u+m, because shcomp pre-expands the preset aliases.)
src/cmd/ksh93/sh/shcomp.c:
- Instead of keeping its own version date (not changed since 2003),
use the same version string as ksh itself (SH_RELEASE).
- Use SH_RELEASE_CPYR for the extra 93u+m copyright string.
- Use SHCOMP_HDR_VERSION for the bytecode header.
src/cmd/ksh93/sh/parse.c: sh_parse():
- Use SHCOMP_HDR_VERSION for the bytecode version check.
src/cmd/ksh93/data/builtins.c: opt_ksh[]:
- Use SH_RELEASE_CPYR for the extra 93u+m copyright string.
src/cmd/ksh93/COMPATIBILITY:
- Mention that 93u+m shcomp bytecode won't run on older ksh.
- Document changes in printf %T (re: 9526b3fa).
src/cmd/ksh93/README:
- Mention that we run on UnixWare (with major regressions).
https://github.com/ksh93/ksh/pull/159#issuecomment-764667929
This fixes the following:
trap ':' DEBUG
r=$(exit 123)
echo $? # Expected 123, but actually 0.
Thanks to Koichi Nakashima for the report and reproducer.
src/cmd/ksh93/sh/fault.c: sh_trap():
- Restore the saved current exit status (exitval) for all traps.
Do not except the DEBUG trap from doing that. I've no idea why
this exception was made, but it's not correct.
src/cmd/ksh93/tests/basic.sh:
- Add tests.
Makes progress on: https://github.com/ksh93/ksh/issues/155
This commit also further mitigates the problems with restoring an
inaccessible or nonexistent PWD on exiting a virtual subshell.
Harald van Dijk writes:
> On a build of ksh with -fsanitize=undefined to help diagnose
> problems:
>
> $ mkdir deleted
> $ cd deleted
> $ rmdir ../deleted
> $ ksh -c '(cd /; (cd /)); :'
> /home/harald/ksh/src/cmd/ksh93/sh/subshell.c:561:22: runtime
> error: null pointer passed as argument 1, which is declared to
> never be null
> Segmentation fault (core dumped)
>
> Note that it segfaults the same with default compilation flags,
> but it does not print out the useful extra message. The code
> assumes that pwd is non-null and passes it to strcmp without
> checking, but it will be null if the current directory cannot be
> determined, for instance because it has been deleted.
src/cmd/ksh93/sh/subshell.c: sh_subshell():
- Avoid the null pointer dereference reported above.
src/cmd/ksh93/bltins/cd_pwd.c: b_cd():
- Fork a virtual subshell even on systems with fchdir(2) if the
present working directory tests as inaccessible on invoking 'cd';
it may no longer exist and fchdir would fail to get a handle.
(For the test we have to opendir(3) the full path to the PWD and
not ".", as the latter may succeed even if the PWD is gone.)
src/cmd/ksh93/data/builtins.c:
- Update 'cd' version string.
Fixes: https://github.com/ksh93/ksh/issues/153
Related: https://github.com/ksh93/ksh/issues/141
src/cmd/ksh93/sh/main.c: sh_main():
- Reading the code makes it obvious that the shp->comdiv-- decrease
in the 'else' block is never reached unless that pointer is still
null, in which case it makes no sense to decrease it. Must be
some kind of missed leftover from old code. Remove the decrease.
This change is backported from the abandoned ksh 93v- beta.
src/cmd/ksh93/sh/subshell.c: sh_subsavefd():
- Do not subtract 1 from fd, as this would cause a negative shift
operand for stdin (fd==0).
This now makes ksh build on DragonFly BSD.
bin/package, src/cmd/INIT/package.sh:
- DragonFly also needs the -lm hack for LDFLAGS.
src/cmd/ksh93/sh/main.c, src/cmd/ksh93/tests/basic.sh:
- fixargs() doesn't work on DragonFly either
(re: 9b7c392a, 159fb9ee, cefe087d).
The following are backported from:
https://github.com/att/ast/issues/26#issuecomment-313927854https://github.com/att/ast/pull/19
src/lib/libast/comp/setlocale.c:
- Add missing #include <errno.h> since errno is used.
src/lib/libast/features/standards:
- Do not set any standards macros (_POSIX_SOURCE etc) on FreeBSD or
DragonflyBSD; they disable too much functionality on those.
src/lib/libast/features/wchar:
- Set _STDFILE_DECLARED on DragonFly, too.
src/lib/libast/include/sfio.h, src/lib/libast/include/sfio_t.h,
src/lib/libast/sfio/_sfopen.c, src/lib/libast/sfio/sfclrlock.c,
src/lib/libast/sfio/sfhdr.h, src/lib/libast/sfio/sfnew.c,
src/lib/libast/sfio/sfset.c:
- Rename SF_* macros to SFIO_* to avoid a conflict with system
headers.
src/lib/libast/string/strexpr.c:
- Rename error() to err() to avoid a conflict.
src/cmd/ksh93/sh/main.c: fixargs():
- Erase the entire length of the command arguments buffer (the
space from argv[0] until environ[0]) so that remnants of longer
command arguments aren't left in 'ps' output when executing a
hashbang-ess script with a shorter command line.
- Disable fixargs() on FreeBSD. It has never had any effect on that
system; apparently it either requires another method to rewrite
arguments for 'ps' output purposes (which?) or it's not possible.
src/cmd/ksh93/tests/basic.sh:
- Skip the test if running on FreeBSD.
This applies a patch from Solaris:
https://github.com/oracle/solaris-userland/blob/master/components/ksh93/patches/160-CR7175995.patch
There is no public information on why it's needed, but it seems
sensible on the face of it. Using a file called '.profile' in the
PWD on login, without a directory path, is redundant at best, since
"$HOME/.profile" (e_profile, see data/msg.c) is already used. And
if the PWD is not $HOME at login time, it seems to me there are
serious problems and the last thing you want is to read some
random and probably dodgy '.profile' from the PWD.
src/cmd/ksh93/sh/init.c: sh_init(): login_files[]:
- Remove redundant/problematic ".profile" entry.
$KSH_VERSION is initialised as a nameref to ${.sh.version}, but it
was not realiable as it could be overridden from the environment.
Some scripts do version checking so this would allow influencing
their execution.
This fix is inspired by the following Solaris patch:
https://github.com/oracle/solaris-userland/blob/master/components/ksh93/patches/200-17435456.patch
but a different approach was needed, because the code has changed
(see 960a1a99).
src/cmd/ksh93/sh/init.c: env_init():
- Refuse to import $KSH_VERSION. Using strncmp(3) might be crude,
but it's effective and I can't figure out another way.
This fixes the following bug filed with Solaris: "22964338 ksh93
appears to send SIGHUP to unrelated processes on occasion". It is
fixed by applying this patch by Lijo George from the Solaris repo:
https://github.com/oracle/solaris-userland/blob/master/components/ksh93/patches/260-22964338.patch
The ksh2020 upstream rejected this, but if it's in production use
in Solaris, Solaris, it's probably good enough for 93u+m. If any
breakage is left, it can be fixed later.
https://github.com/att/ast/pull/1
src/cmd/ksh93/include/jobs.h,
src/cmd/ksh93/sh/fault.c,
src/cmd/ksh93/sh/jobs.c:
- Use a new job_hup() function instead of job_kill() to send SIGHUP
to job processes on termination. The new function checks if a job
is in fact still live before issuing SIGHUP to it.
This pulls a new version of sh_iosafefd() from:
https://github.com/oracle/solaris-userland/blob/master/components/ksh93/patches/285-30771135.patch
It was written by Kurtis Rader for ksh2020:
https://github.com/att/ast/issues/198https://github.com/att/ast/pull/199
It is presumably better than the Red Hat version and also comes
with more regression test cases (although it still doesn't fix
modernish BUG_CSUBSTDO, which remains in the TODO file).
This commit does not go along with other peripheral changes from
that patch, i.e. a different name and location of this function.
src/cmd/ksh93/sh/io.c:
- Replace sh_iosafefd() as above.
src/cmd/ksh93/tests/subshell.sh:
- Add and tweak tests from the patch.
This change is pulled from here:
https://github.com/oracle/solaris-userland/blob/master/components/ksh93/patches/280-23332860.patch
Info and reproducers:
https://github.com/att/ast/issues/36
In a -c script (like ksh -c 'commands'), the last command
misredirects standard output if an EXIT or ERR trap is set.
This appears to be a side effect of the optimisation that
runs the last command without forking.
This applies a patch by George Lijo that flags these specific
cases and disables the optimisation.
src/cmd/ksh93/include/defs.h,
src/cmd/ksh93/bltins/trap.c,
src/cmd/ksh93/sh/init.c,
src/cmd/ksh93/sh/main.c,
src/cmd/ksh93/sh/xec.c:
- Apply patch as above.
src/cmd/ksh93/tests/io.sh:
- Add the reproducers from the bug report as regression tests.
This change is pulled from here:
https://github.com/oracle/solaris-userland/blob/master/components/ksh93/patches/275-20855453.patchhttps://github.com/att/ast/issues/30
George Lijo wrote on 17 Feb 2017:
> Here's a reproducible testcase on a Solaris11 host running
> ksh93u+(2012-08-01).
> $ cat a.sh
> #!/bin/sh
>
> AAA="aaa"
> echo 'insert character'
> BBB=`echo ${AAA} | sed "s/aaa/bbb/g"`
> logger "variable BBB = ${BBB}"
>
> $ cat t.sh
> #!/bin/ksh
>
> sleep 10
> /bin/ksh ./a.sh
> exit 0
>
> $
>
> $ ./t.sh
>
> The expected result is:
>
> Apr 9 12:43:34 lab user: [ID 702911 user.notice] variable BBB = bbb
>
> because variable "BBB" is supposed to be set to 'bbb' in a.sh.
>
> But if the parent shell is terminated, the variable is wrongly set.
>
> user@xxxxx$ telnet lab
> ...
> $ ./t.sh & <--- Run t.sh in background.
> [1] 2067
> $ logout <--- CTRL + D to exit while t.sh is running.
> Connection to lab closed by foreign host.
>
> Again, access the system and check the output:
>
> user@xxxxx$ telnet lab
> ...
> $ tail -f /var/adm/messages
> :
> Apr 9 12:47:47 lab user: [ID 702911 user.notice] variable BBB =
> insert character <--- !!!
> Apr 9 12:47:47 lab bbb
> <--- !!!
>
> Thus the variable is wrongly set. (The previous echo string was
> not cleared.)
>
> The issue happens because the EIO error during the logout is not
> handled properly.
src/cmd/ksh93/sh/io.c,
src/lib/libast/include/error.h:
- Amend the ERROR_PIPE() macro to check for EIO as well as EPIPE
and ECONNRESET.
This change is pulled from here:
https://github.com/oracle/solaris-userland/blob/master/components/ksh93/patches/110-CR7061011.patch
Unfortunately there is no publicly available documentation on why
this change was needed. We just have to assume the Solaris people
knew what they were doing. ksh2020 upstreamed this too (as well as
all the other Solaris patches applied here).
src/cmd/ksh93/sh/nvdisc.c: setdisc():
- If no <event> is known for <np>, return a null pointer instead
of a pointer to the empty string.
The forking fix implemented in 102868f8 and 9d428f8f, which stops
the main shell's hash table from being cleared if PATH is changed
in a subshell, can cause a significant performance penalty for
certain scripts that do something like
( PATH=... command foo )
in a subshell, especially if done repeatedly. This is because the
hash table is cleared (and hence a subshell forks) even for
temporary PATH assignments preceding commands.
It also just plain doesn't work. For instance:
$ hash -r; (ls) >/dev/null; hash
ls=/bin/ls
Simply running an external command in a subshell caches the path in
the hash table that is shared with a main shell. To remedy this, we
would have to fork the subshell before forking any external
command. And that would be an unacceptable performance regression.
Virtual subshells do not need to fork when changing PATH if they
get their own hash tables. This commit adds these. The code for
alias subshell trees (which was removed in ec888867 because they
were broken and unneeded) provided the beginning of a template for
their implementation.
src/cmd/ksh93/sh/subshell.c:
- struct subshell: Add strack pointer to subshell hash table.
- Add sh_subtracktree(): return pointer to subshell hash table.
- sh_subfuntree(): Refactor a bit for legibility.
- sh_subshell(): Add code for cleaning up subshell hash table.
src/cmd/ksh93/sh/name.c:
- nv_putval(): Remove code to fork a subshell upon resetting PATH.
- nv_rehash(): When in a subshell, invalidate a hash table entry
for a subshell by creating the subshell scope if needed, then
giving that entry the NV_NOALIAS attribute to invalidate it.
src/cmd/ksh93/sh/path.c: path_search():
- To set a tracked alias/hash table entry, use sh_subtracktree()
and pass the HASH_NOSCOPE flag to nv_search() so that any new
entries are added to the current subshell table (if any) and do
not influence any parent scopes.
src/cmd/ksh93/bltins/typeset.c: b_alias():
- b_alias(): For hash table entries, use sh_subtracktree() instead
of forking a subshell. Keep forking for normal aliases.
- setall(): To set a tracked alias/hash table entry, pass the
HASH_NOSCOPE flag to nv_search() so that any new entries are
added to the current subshell table (if any) and do not influence
any parent scopes.
src/cmd/ksh93/sh/init.c: put_restricted():
- Update code for clearing the hash table (when changing $PATH) to
use sh_subtracktree().
src/cmd/ksh93/bltins/cd_pwd.c:
- When invalidating path name bindings to relative paths, use the
subshell hash tree if applicable by calling sh_subtracktree().
- rehash(): Call nv_rehash() instead of _nv_unset()ting the hash
table entry; this is needed to work correctly in subshells.
src/cmd/ksh93/tests/leaks.sh:
- Add leak tests for various PATH-related operations in the main
shell and in a virtual subshell.
- Several pre-existing memory leaks are exposed by the new tests
(I've confirmed these in 93u+). The tests are disabled and marked
TODO for now, as these bugs have not yet been fixed.
src/cmd/ksh93/tests/subshell.sh:
- Update.
Resolves: https://github.com/ksh93/ksh/issues/66
The SHOPT_2DMATCH code block in sh_setmatch() modifies the 'ap'
pointer, which is initialised as nv_arrayptr(SH_MATCHNOD). This
caused a (rarely occurring) segfault in the following line near the
end of the function:
ap->nelem -= x;
as this line assumed that 'ap' still had the initial value.
src/cmd/ksh93/sh/init.c: sh_setmatch():
- On init, save ap in ap_save and use ap_save instead of ap where
it should be pointing to SH_MATCHNOD. This also allows removing
two redundant nv_arrayptr(SH_MATCHNOD) calls, slightly increasing
the efficiency of this function.
Scripts that use floating point shell arithmetic confusingly fail
with 'arithmetic syntax error' when running in a locale that uses
',' as the radix point, because '.' is generally assumed by
scripts. The error message is confounding as the problem is not a
syntax error but a locale that is incompatible with the script.
src/cmd/ksh93/sh/arith.c:
- If the locale's radix point is not '.' but a '.' is found in its
place, issue an informative error message that instructs setting
LC_NUMERIC=C.
Resolves: https://github.com/ksh93/ksh/issues/145
As of this commit, ksh 93u+m has a standard semantic version number
<https://semver.org/>, beginning with 1.0.0-alpha. This is added to
the version string in a way that should be compatible with scripts
parsing ${.sh.version} or $(ksh --version). This addition does not
replace the release date and does not affect $((.sh.version)).
For non-release builds, the version string will be:
FORK/VERSION+HASH YYYY-MM-DD
e.g.: 93u+m/1.0.0-alpha+41ef7f76 2021-01-03
For release builds, it will be:
FORK/VERSION YYYY-MM-DD
e.g.: 93u+m/1.0.0 2021-01-03
It is now automatically decided by bin/package whether to build a
release or development build. When building from a directory that
is not a git repository, or if the current git branch name starts
with a number (e.g. '1.0'), the release build is enabled; otherwise
a development build is the default. This is arranged by adding -D
flags to $CCFLAGS as described below. These flags are prepended to
$CCFLAGS, so they can be overridden by adding your own -D or -U
flags via the environment.
In addition, AST vmalloc is disabled for release builds as of this
commit, forcing the use of the OS's standard malloc(3). In 2021,
this is generally more reliable, faster, and more economical with
memory than AST vmalloc. Several memory leaks and crashing bugs are
avoided, e.g.: <https://github.com/ksh93/ksh/issues/95>.
For development builds, vmalloc stays enabled (along with its known
bugs) because this allows the use of the vmstat builtin, making it
much more efficient to test for memory leaks. For more info, see
the regression test script: src/cmd/ksh93/tests/leaks.sh
bin/package, src/cmd/INIT/package.sh:
- Add flags for build type. In $CCFLAGS, define _AST_ksh_release if
we're not on any git branch or on a git branch whose name starts
with a number. Otherwise, define _AST_git_commit as the first 8
characters of the current git commit hash.
src/lib/libast/features/vmalloc:
- If _AST_ksh_release is defined, disable vmalloc and force use of
the operating system's malloc. Discussion:
https://github.com/ksh93/ksh/issues/95
src/cmd/ksh93/include/version.h:
- Define new format for version string, adding a semantic version
number as well as (for non-release builds) the git commit hash.
src/cmd/ksh93/sh/init.c: e_version[]:
- Add a 'v' to the ${.sh.version} feature string if ksh was
compiled with vmalloc enabled. This allows scripts, such as
regression tests, to detect this.
src/cmd/ksh93/data/builtins.c: sh_optksh[]:
- Add a copyright line crediting the contributors to ksh 93u+m.
Resolves: https://github.com/ksh93/ksh/issues/95
