As of 8477d2ce, the mbwide() macro (which tests if we're in a
multibyte locale, i.e. UTF-8) is redefined as a constant 0 if we're
compiling without SHOPT_MULTIBYTE. See src/cmd/ksh93/include/defs.h
The other multibyte macros use mbwide() as well, so they all revert
to the single-byte fallbacks in that case, and the multibyte code
in them is never compiled. See src/lib/libast/include/ast.h
Consequently we can now do a bit of cleanup and get rid of many of
the '#if SHOPT_MULTIBYTE' directives, as the compiler optimiser
will happily remove the multibyte-specific code. This increases the
legibility of the ksh code.
I'm taking the opportunity to fix a few typos and whitespace
formatting glitches as well.
This fixes a hanging bug that could occur on macOS when using the
'read' command to read from a FIFO and encountering end-of-file
without a final newline character. It also makes the 'read' command
perform 15-25% faster on macOS and Linux.
The previous version (ff385e5a) failed on SunOS/Solaris/Illumos
because those systems apparently don't (fully) support the POSIX
standard recv(2) syscall with MSG_PEEK[*], which is the feature
that iffe detects under the 'socket_peek' identifier. On Illumos,
using that methods causes a compilation failure (unknown identifier
MSG_PEEK); on Solaris 11.4, that method causes multiple regressions
in tests/io.sh, suggesting the method compiles but doesn't work at
all. Instead, SunOS/Solaris/Illumos requires the method using
ioctl(2)+I_PEEK and select(2). No other system that ksh currently
builds on requires this method, so it is now only used on
SunOS/Solaris/Illumos.
So far, this version of sfpkrd() has been tested to work correctly
on Linux, macOS, FreeBSD, NetBSD, OpenBSD, HP-UX, Solaris, and
OmniOS (an Illumos distribution).
It still fails to peek on Cygwin, but in the exact same way it
failed before, so that's no loss.
To test, run the 'io' test set: bin/shtests -p io
src/lib/libast/sfio/sfpkrd.c: sfpkrd():
- Remove long-obsolete Mac OS X and Solaris bug workarounds.
- Remove methods that are no longer needed.
On systems with a POSIX compliant recv(2), the only thing that
is required to avoid regressions is the code that was conditional
upon the socket_peek feature test, which tests for the correct
functioning of the recv(2) syscall. This has now been made
mandatory for non-SunOS/Solaris/Illumos systems (using an #error
directive if it is not detected), with the other methods removed.
The result performs 15-25% faster on macOS and Linux while
passing all the regression tests.
On macOS, avoiding the select(2) method fixes the hanging bug.
On SunOS/Solaris/Illumos (the '__sun' identifier), the method
using ioctl(2)+I_PEEK and select(2) (iffe feature IDs:
stream_peek and lib_select) is preserved.
Resolves: https://github.com/ksh93/ksh/issues/118 (again)
[*] https://pubs.opengroup.org/onlinepubs/9699919799/functions/recv.html
This fixes a hanging bug that could occur on macOS when using the
'read' command to read from a FIFO and encountering end-of-file
without a final newline character. It also makes the 'read' command
perform 15-25% faster on macOS and Linux and maybe other systems.
src/lib/libast/sfio/sfpkrd.c: sfpkrd():
- Get rid of the optional stuff that uses the poll(2) or select(2)
syscalls. The only thing that is required to avoid regressions is
the code that was conditional upon the socket_peek feature test,
which tests for the correct functioning of the recv(2) syscall.
This has now been made mandatory. The rest now uses what was
previously a fallback in plain C, resulting in a function that is
not only more readable, but actually faster than the syscalls.
Resolves: https://github.com/ksh93/ksh/issues/118
CDE <https://cdesktopenv.sf.net/> developer Chase writes, re dtksh:
| Everything is now completely working, and we are almost ready to
| add ksh93 as a submodule, but I have one last commit to get rid
| of some warnings we are facing. nval.h has some of these
| "compatiblity redefines" that are causing issues whenever we
| include it (warnings about redefining values) [...].
src/cmd/ksh93/include/nval.h:
- Replace ancient compatibility redefines by an unconditional
'#include <hash.h>'; ksh works fine with the "new" hash library.
Co-authored-by: Martijn Dekker <martijn@inlv.org>
If a command's path was previously added to the hash table as a
'tracked alias', then the hash table entry was used, bypassing
the default utility path search activated by 'command -p'.
'command -p' activates a SH_DEFPATH shell state. The bug was caused
by a failure to check for this state before using the hash table.
This check needs to be added in four places.
src/cmd/ksh93/sh/path.c,
src/cmd/ksh93/sh/xec.c:
- path_search(), path_spawn(), sh_exec(), sh_ntfork(): Only consult
the hash table, which is shp->track_tree, if the SH_DEFPATH shell
state is not active.
src/cmd/ksh93/tests/path.sh:
- Add regress tests checking that 'command -p' and 'command -p -v'
still search in the default path if a hash table entry exists for
the command searched.
A memory leak occurred upon leaving a virtual subshell if a
function was defined within it. If this was done more than 32766
(= 2^15-2 = the 'short' max value - 1) times, the shell crashed.
Discussion and reproducer: https://github.com/ksh93/ksh/issues/114
src/cmd/ksh93/sh/subshell.c: table_unset():
- A subshell-defined function was never freed because a broken
check for autoloaded functions (which must not be freed[*]). It
looked for an initial '/' in the canonical path of the script
file that defined the function, but that path is also stored for
regular functions. Now use a check that executes nv_search() in
fpathdict, the same method used in _nv_unset() in name.c for a
regular function unset.
src/cmd/ksh93/bltins/misc.c: b_dot_cmd():
- Fix an additional memory leak introduced in bd88cc7f, that caused
POSIX functions (which are run with b_dot_cmd() like dot scripts)
to leak extra. This fix avoids both the crash fixed there and the
memory leak by introducing a 'tofree' variable remembering the
filename to free. Thanks to Johnothan King for the patch.
src/lib/libast/include/stk.h,
src/lib/libast/misc/stk.c,
src/lib/libast/man/stk.3,
src/lib/libast/man/stak.3:
- Make the stack more resilient by extending the stack reference
counter 'stkref' from (signed) short to unsigned int. On modern
systems with 32-bit ints, this extends the maximum number of
elements on a stack from 2^15-1==32767 to 2^32-1==4294967295.
The ref counter can never be negative, so there is no reason for
signedness. sizeof(int) is defined as the size of a single CPU
word, so this should not affect performance at all.
On a 16-bit system (not that ksh still compiles there), this
doubles the max number of entries to 2^16-1=65535.
src/cmd/ksh93/tests/leaks.sh:
- Add leak regression tests for ksh functions, POSIX functions, dot
scripts run with '.', and dot scripts run with 'source'.
src/cmd/ksh93/tests/path.sh:
- Add an output builtin with a redirect to an autoloaded function
so that a crash[*] is triggered if the check for an autoloaded
function is ever removed from table_unset(), as was done in ksh
93v- (which crashed).
[*] Freeing autoloaded functions after leaving a virtual subshell
causes a crashing bug: https://github.com/att/ast/issues/803
Co-authored-by: Johnothan King <johnothanking@protonmail.com>
Fixes: https://github.com/ksh93/ksh/issues/114
Co-authored-by: Martijn Dekker <martijn@inlv.org>
An intermittent crash occurred after running many thousands of
virtual/non-forked subshells. One reproducer is a crash in the
shbench fibonacci.ksh test, as documented here:
https://github.com/ksh-community/shbench/blob/f3d9e134/bench/fibonacci.ksh#L4-L10
The apparent cause was the signed and insufficiently large 'short'
data type of 'curenv' and related variables which wrapped around to
a negative number when overflowing. These IDs are necessary for the
'wait' builtin to obtain the exit status from a background job.
This fix is inspired by a patch based on ksh 93v-:
https://build.opensuse.org/package/view_file/shells/ksh/ksh93-longenv.dif?expand=1https://src.fedoraproject.org/rpms/ksh/blob/f24/f/ksh-20130628-longer.patch
However, we change the type to 'unsigned int' instead of 'long'. On
all remotely modern systems, ints are 32-bit values, and using this
type avoids a performance degradation on 32-bit sytems. Making them
unsigned prevents an overflow to negative values.
src/cmd/ksh93/include/defs.h,
src/cmd/ksh93/include/jobs.h,
src/cmd/ksh93/include/nval.h,
src/cmd/ksh93/include/shell.h:
- Change the types of the static global 'subenv' and the subshell
structure members 'curenv', 'jobenv', 'subenv', 'p_env' and
'subshell' to one consistent type, unsigned int.
src/cmd/ksh93/sh/jobs.c,
src/cmd/ksh93/sh/macro.c:
src/cmd/ksh93/sh/name.c:
src/cmd/ksh93/sh/nvtype.c,
src/cmd/ksh93/sh/subshell.c:
- Updates to match new variable types.
src/cmd/ksh93/tests/subshell.sh:
- Show wrong exit status in message on failure of 'wait' builtin.
As of aa4669ad, astconf("PATH") is implemented as a hardcoded AST
configuration variable that always has a value, instead of one that
falls back on the OS. Its value is now obtained from the OS (with a
fallback) at configure time and not at runtime. This means that any
fallback for astconf("PATH") is now never used.
src/cmd/ksh93/data/msg.c,
src/cmd/ksh93/include/shell.h:
- Remove e_defpath[]. (The path "/bin:/usr/bin:" made no sense as a
default path anyway, as the final empty element is wrong: default
utilities should never be sought in the current working dir.)
src/cmd/ksh93/sh/path.c,
src/lib/libast/path/pathbin.c:
- abort() if astconf("PATH") returns null.
src/lib/libast/comp/conf.tab: PATH:
- If no 'getconf' utility can be found, use a fallback path that
finds more utilities by also searching in 'sbin' directories.
On some systems, this is needed to find chown(1).
src/cmd/ksh93/sh.1:
- Update doc re default path.
The entity is not valid in XML, only in HTML. Since we must
be compatible with both, it can't be used. Thanks to Andras Farkas
for the bug report.
In addition, the generation of numeric entities for unprintable
characters was only valid while processing UTF-8 text while in a
UTF-8 locale. In all other conditions it produced invalid results.
This is not worth trying to fix.
Discussion:
https://groups.google.com/d/msgid/korn-shell/CAA0nTRta%3DPbOYduyBv%3DXCzumTcUCU8Lki%3DQQf2O8Erk2BFvO1g%40mail.gmail.com
src/cmd/ksh93/bltins/print.c:
- Remove conversion to entity.
- Remove conversion of non-graph characters to numeric entities.
Convert only the 5 semantically meaningful characters: < > & " '
src/cmd/ksh93/include/defs.h,
src/cmd/ksh93/sh/string.c:
- We don't need sh_isprint() in print.c anymore, so turn it back
into a static function.
src/cmd/ksh93/tests/builtins.sh:
- Update and trim regression tests.
This applies a number of fixes to the printf formatting directives
%H and %#H (as well as their equivalents %(html)q and %(url)q):
1. Both formatters have been made multibyte/UTF-8 aware, and no
longer delete multibyte characters. Invalid UTF-8 byte sequences
are rendered as ASCII question marks.
2. %H no longer wrongly encodes spaces as non-breaking spaces
( ) and instead correctly encodes the UTF-8 non-breaking
space as such.
3. %H now converts the single quote (') to '%#39;' instead of
''' which is not a valid entity in all HTML versions.
4. %#H failed to encode some reserved characters (e.g. '?') while
encoding some unreserved ones (e.g. '~'). It now percent-encodes
all characters except those 'unreserved' as per RFC3986 (ASCII
alphanumeric plus -._~).
Prior discussion:
https://groups.google.com/d/msgid/korn-shell/ce8d1467-4a6d-883b-45ad-fc3c7b90e681%40inlv.org
src/cmd/ksh93/include/defs.h:
src/cmd/ksh93/sh/string.c:
- defs.h: If compiling without SHOPT_MULTIBYTE, redefine the
mbwide() macro (which tests if we're in a multibyte locale) as 0.
This lets the compiler optimiser do the work that would otherwise
require a lot of tedious '#if SHOPT_MULTIBYTE' directives.
- string.c: Remove some now-unneeded '#if SHOPT_MULTIBYTE' stuff.
- defs.h, string.c: Rename is_invisible() to sh_isprint(), invert
the boolean return value, and make it an extern for use in
fmthtml() -- see below. If compiling without SHOPT_MULTIBYTE,
simply #define sh_isprint() as equivalent to isprint(3).
- defs.h: Add URI_RFC3986_UNRESERVED macro for fmthtml() containing
the characters "unreserved" for purposes of URI percent-encoding.
src/cmd/ksh93/bltins/print.c: fmthtml():
- Remove kludge that skipped all multibyte characters (!).
- Complete rewrite to implement fixes described above.
- Don't bother with '#if SHOPT_MULTIBYTE' directives (see above).
src/cmd/ksh93/data/builtins.c:
- sh_optprintf[]: %H: Add single quote to encoded chars doc.
- Edit credits and bump version date.
src/cmd/ksh93/tests/builtins.sh:
- Update and tweak old regression tests.
- Add a number of new tests for UTF-8 HTML and URI encoding, which
are only run when running tests in a UTF-8 locale (shtests -u).
There are convincing arguments why including '.' and '..' in the
result of pathname expansion is actively harmful. See:
https://www.austingroupbugs.net/view.php?id=1228https://github.com/ksh93/ksh/issues/58#issuecomment-653716846
pdksh, mksh and zsh already skip these special traversal names
in all cases. This commit makes ksh act like these shells.
Since passing '.' and especially '..' as arguments to commands like
'chmod -R' and 'cp -r' may cause harm, this change seems likely to
fix more legacy scripts than it breaks. I'm unaware of anyone ever
having come up with a concrete use case for the old behaviour.
This change also fixes the bug that '.' and '..' failed to be
ignored as documented if FIGNORE is set.
src/lib/libast/misc/glob.c: glob_dir():
- Explicitly skip any matching '.' and '..' in all cases.
src/cmd/ksh93/tests/glob.sh:
- Add test_glob() tests for '*' and '.*'.
src/cmd/ksh93/sh.1: File Name Generation:
- Update to match new behaviour.
Resolves: https://github.com/ksh93/ksh/issues/58
The 'redirect' builtin command did not error out before executing
any valid redirections. For example, 'redirect ls >foo.txt' issued
an "incorrect syntax" error, but still created 'foo.txt' and left
standard output permanently redirected to it.
src/cmd/ksh93/sh/xec.c: sh_exec():
- If we have redirections (io != NULL), and the command is
SYSREDIR, then check for arguments and error out if there are
any, before calling sh_redirect() to execute redirections.
(Note, the other check for arguments in b_exec() in bltins/misc.c
must be kept, as that applies if there are no redirections.)
src/cmd/ksh93/sh/io.c: sh_redirect():
- Edit comments to better explain what the flag values do.
src/cmd/ksh93/bltins/misc.c:
- Add a dummy b_redirect() function declaration "for the dictionary
generator" as has historically been done for other builtins that
share one C function. I'm not sure what that dictionary generator
is supposed to be, but this also improves greppability.
src/cmd/ksh93/data/builtins.c,
src/cmd/ksh93/sh.1:
- Fix misleading "I/O redirection arguments" term. I/O redirections
are not arguments at all; no argument parser ever sees them.
src/cmd/ksh93/tests/io.sh:
- Test both conditions that should make 'redirect' produce an
"incorrect syntax" error.
- Test that any redirections are not executed if erroneous
non-redirection arguments exist.
src/cmd/ksh93/tests/builtins.sh:
- "... should show usage info on unrecognized options" test:
Because 'redirect' now refuses to process redirections on error,
the error message was not captured. The fix is to run the builtin
in a braces block and add the redirection to the block.
The crash in job_list() or job_unpost() could still occur after the
previous patch if a signal was being handled after $TMOUT was
exceeded and the 60-second grace period was entered.
It *should* work to add a general check for !sh_isstate(SH_GRACE).
We know that the SH_GRACE state is set immediately after printing
the 60 second grace period warning message:
https://github.com/ksh93/ksh/blob/9de65210/src/cmd/ksh93/sh/io.c#L1869-L1870
(and that the crashes occur upon re-evaluating the $PS1 prompt
after setting the SH_GRACE state). We know that the SH_GRACE state
is not turned off again until either the user enters a line:
https://github.com/ksh93/ksh/blob/9de65210/src/cmd/ksh93/sh/main.c#L474
or the shell times out after the grace period:
https://github.com/ksh93/ksh/blob/9de65210/src/cmd/ksh93/sh/io.c#L1861
The SH_GRACE state flag is not used or changed in any other context
(verified with grep -rn SH_GRACE src/cmd/ksh93). So, logically,
this should suffice to make sure the crash stays gone.
src/cmd/ksh93/sh/jobs.c: job_reap():
- Do not list jobs when the SH_GRACE state (the 60 second timeout
grace period after TMOUT was exceeded) is active.
- Keep the previous check for job control just to be sure, and
because it makes sense.
Fixes: https://github.com/ksh93/ksh/issues/103 (again)
This variable is like Bash's $BASHPID, but in virtual subshells
it will retain its previous value as virtual subshells don't fork.
Both $BASHPID and ${.sh.pid} are different from $$ as the latter
is only set to the parent shell's process ID (i.e. it isn't set
to the process ID of the current subshell).
src/cmd/ksh93/include/defs.h:
- Add 'current_pid' for storing the current process ID at a valid
memory address.
- Change 'ppid' from 'int32_t' to 'pid_t', as the return value from
'getppid' is of the 'pid_t' data type.
src/cmd/ksh93/data/variables.c,
src/cmd/ksh93/include/variables.h,
src/cmd/ksh93/sh/init.c,
src/cmd/ksh93/sh/xec.c:
- Add the ${.sh.pid} variable as an alternative to $BASHPID.
The process ID is stored in a struct before ${.sh.pid} is set
as environment variables are pointers that must point to a
valid memory address. ${.sh.pid} is updated by the _sh_fork()
function, which is called when ksh forks a new process with
sh_fork() or sh_ntfork().
src/cmd/ksh93/tests/variables.sh:
- Add ${.sh.pid} to the list of special variables and add three
regression tests for ${.sh.pid}.
src/cmd/ksh93/tests/subshell.sh:
- Update the PATH forking regression test to use ${.sh.pid} and
remove the TODO note.
This bug caused an undefined state, which sometimes crashed the
shell in job_list() or job_unpost(), if $PS1 contains a command
substitution running an external command and the '-b'/'-o notify'
shell option is active. So far the only known way to trigger the
crash is by letting $TMOUT time out the interactive shell. See
https://github.com/ksh93/ksh/issues/103 for details.
src/cmd/ksh93/sh/jobs.c: job_reap():
- The check for the SH_NOTIFY option and the SH_TTYWAIT state
before listing jobs was insufficient. Job control is disabled in
command substitutions, so also check that job control is active
before listing jobs.
src/cmd/ksh93/sh.1:
- Fix TMOUT documentation. The 'read' command in fact only times
out when reading from a terminal, just like 'select'. Also
document the extra 60 second grace period when an interactive
shell prompt reads from a terminal.
Fixes: https://github.com/ksh93/ksh/issues/103
The liblist variable needs to be an extern for dtksh to build.
Quote from CDE developer Chase:
we use an old function that no longer appears in kornshell,
sh_getliblist, it seems to be replaced by the function sh_getlib,
which is fine, but it seems to return a "Shbltin_f" type, which I
can't seem to find any information on what it is. We need the void
pointer dlsym provides for some widget init stuff, I tried making
liblist an extern, but it kept giving me an error about libcomp_t
being undefined.
src/cmd/ksh93/bltins/typeset.c,
src/cmd/ksh93/include/shell.h:
- Fix the compiler error reported above by moving the type definition
for Libcomp_t to shell.h.
- Make liblist an extern since findsym.c in dtksh needs it to build.
The old sh_getliblist function doesn't need to be reintroduced
since the only purpose it served was to workaround the problem
of liblist being a static variable. Now that liblist is an extern,
dtksh fsym can use liblist directly to avoid sh_getliblist.
dtksh findsym.c:
https://sourceforge.net/p/cdesktopenv/code/ci/2.3.2/tree/cde/programs/dtksh/findsym.c
The required longjmp used to terminate scripts was not being run
when over-shifting in a POSIX function with a redirection. This
caused scripts to continue after an error in the shift builtin,
which is incorrect since shift is a special builtin. The
interpreter is sent into an indeterminate state that causes
undefined behavior as well:
$ cat reproducer.ksh
some_func() {
shift 10
}
for i in a b c d e f; do
echo "read $i"
[ "$i" != "c" ] && continue
some_func 2>&1
echo "$i = c"
done
$ ksh ./reproducer.ksh
read a
read b
read c
/tmp/k[2]: shift: 10: bad number
c = c
read d
/tmp/k[2]: shift: 10: bad number
d = c
read e
/tmp/k[2]: shift: 10: bad number
e = c
read f
/tmp/k[2]: shift: 10: bad number
f = c
src/cmd/ksh93/sh/xec.c: sh_exec():
- Do the necessary longjmp needed to terminate the script after
over-shifting in a POSIX function when the function call has a
redirection.
src/cmd/ksh93/tests/functions.sh:
- Add the over-shifting regression test from ksh93v- 2013-10-10-alpha.
Bug report and fix on the old mailing list:
https://www.mail-archive.com/ast-developers@lists.research.att.com/msg00732.html
Multidimensional associative arrays are created with an extra array
member named '0', which is set to no value. Reproducer:
$ typeset -A foo
$ typeset -A foo[bar]
$ typeset -p foo
typeset -A foo=([bar]=([0]='') )
The bugfix prevents nv_setarray from creating the extra '[0]' member
when an associative array is empty. This bug was discussed on the old
mailing list:
https://www.mail-archive.com/ast-developers@lists.research.att.com/msg01574.html
src/cmd/ksh93/sh/array.c:
- Do not allow the creation of an extra array member when an array
is empty.
src/cmd/ksh93/tests/arrays.sh:
- Add a regression test for creating multidimensional associative
arrays, but use the output from 'typeset -p' instead of fgrep.
When the classic fork/exec mechanism was used (via sh_fork()) to
run an external command from within a non-forking subshell, SIGINT
was blocked until that subshell was exited. If a subsequent loop
was run in the subshell, it became uninterruptible, e.g.:
$ arch/*/bin/ksh -c '(/usr/bin/true; while :; do :; done); exit'
^C^C^C^C^C
src/cmd/ksh93/sh/xec.c:
- sh_fork() did not reset the savesig variable in the parent part
of the fork when running in a virtual subshell. This had the
effect of delaying signal handling until exiting the subshell.
There is no reason for that subshell check that I can discern, so
this removes it.
I've verified that this causes no regression test failures
even when ksh is compiled with -DSHOPT_SPAWN=0 which means the
classic fork/exec mechanism is always used.
Fixes: https://github.com/ksh93/ksh/issues/86
Add support for multibyte characters to $IFS
This commit fixes BUG_MULTIBIFS, which had two bug reports in the ksh2020 branch.
src/cmd/ksh93/sh/macro.c:
- Backport Eric Scrivner's fix for multibyte IFS characters (slightly modified
for compatibility with C89). Explanation from https://github.com/att/ast/pull/737:
Previously, the varsub method used for the macro expansion of $param, ${param},
and ${param op word} would incorrectly expand the internal field separator (IFS)
if it was a multibyte character. This was due to truncation based on the
incorrect assumption that the IFS would never be larger than a single byte.
This change fixes this issue by carefully tracking the number of bytes that
should be persisted in the IFS case and ensuring that all bytes are written
during expansion and substitution.
Bug report: https://github.com/att/ast/issues/13
- Fixed another bug that caused multibyte characters with the same initial byte
to be treated as the same character by the IFS. This bug was occurring because
the first byte of a multibyte character wasn't being written to the stack when
the IFS delimiter had the same initial byte:
$ IFS=£
$ v='§'
$ set -- $v
$ v="${1-}"
$ echo "$v" | hd # The first byte should be c2, but it isn't due to the bug
00000000 a7 0a |..|
00000002
Bug report: https://github.com/att/ast/issues/1372
src/cmd/ksh93/tests/variables.sh:
- Add (reworked) regression tests from ksh2020 for the multibyte IFS bugs.
- Add a regression test for att/ast#1372 based on the reproducer.
When a command substitution is run on the same line as a here-document,
a syntax error occurs due to a regression introduced in ksh93u+ 2011-04-15:
true << EOF; true $(true)
EOF
syntax error at line 1: `<<EOF' here-document not contained within command substitution
The regression is caused by an error check that was added to make
the following script causes a syntax error (because the here-document
isn't completed inside of the command substitution):
$(true << EOF)
EOF
src/cmd/ksh93/sh/lex.c:
- Only throw an error when a here-document in a command substitution
isn't completed inside of the command substitution.
src/cmd/ksh93/tests/heredoc.sh:
- Add a regression test for running a command substitution on the
same line as a here-document.
- Add a missed regression test for using here-documents in command
substitutions. This is the original bug that was fixed in ksh93u+
2011-04-15 (it is why the error message was added), but a regression
test for here-documents in command substitutions wasn't added in
that version.
This bugfix was backported from ksh93v- 2013-10-10-alpha.
When ksh is compiled with SHOPT_SPAWN (the default), which uses
posix_spawn(3) or vfork(2) (via sh_ntfork()) to launch external
commands, at least two race conditions occur when launching
external commands while job control is active. See:
https://bugs.launchpad.net/ubuntu/+source/ksh/+bug/1887863/comments/3https://www.mail-archive.com/ast-developers@research.att.com/msg00717.html
The basic issue is that this performance optimisation is
incompatible with job control, because it uses a spawning mechanism
that doesn't copy the parent process' memory pages into the child
process, therefore no state that involves memory can be set before
exec-ing the external program. This makes it impossible to
correctly set the terminal's process group ID in the child process,
something that is essential for job control to work.
src/cmd/ksh93/sh/xec.c:
- Use sh_fork() instead of sh_ntfork() if job control is active.
This uses fork(2), which is 30%-ish slower on most sytems, but
allows for correctly setting the terminal process group.
src/cmd/ksh93/tests/basic.sh:
- Add regression test for the race condition reported in #79.
src/cmd/INIT/cc.darwin:
- Remove hardcoded flag to disable SHOPT_SPAWN on the Mac.
It should be safe to use now.
Fixes https://github.com/ksh93/ksh/issues/79
This merges some fixes to support building dtksh with -DBUILD_DTKSH.
These patches were sent through private email from the CDE developer
Chase. The reason these patches were submitted is because Chase wishes
to include ksh in CDE as an up-to-date git submodule. Quote from Chase:
"... my priority is to get your new version into our code as a git
submodule, and do it quickly before our code bases differ too widely."
Link to CDE project for anyone interested:
https://sourceforge.net/projects/cdesktopenv/
Although the patches were privately discussed, there are some public
emails on the CDE mailing list (links shortened due to long URLs):
ksh-chaos thread: https://bit.ly/3hjJ83b
dtksh alias thread: https://bit.ly/3hkzKfJ
The main fix is for suid_exec, which is now told that /usr/dt is a
valid directory to run from via preprocessor flags. A patch for
Shift-JIS was also submitted, but it isn't in this commit because it
isn't an effective fix for the existing Shift-JIS bugs. I will be
giving that patch some more testing.
From: Chase <nicetrynsa@protonmail.ch>
Co-authored by: Johnothan King <johnothanking@protonmail.com>
'whence -a' is documented to list all possible interpretations of a
command, but failed to list a built-in command if a shell function
by the same name exists or is marked undefined using 'autoload'.
src/cmd/ksh93/bltins/whence.c: whence():
- Refactor and separate the code for reporting functions and
built-in commands so that both can be reported for one name.
src/cmd/ksh93/data/builtins.c: sh_optwhence[]:
- Correct 'whence --man' to document that:
* 'type' is equivalent to 'whence -v'
* '-a' output is like '-v'
src/cmd/ksh93/tests/builtins.sh:
- Test 'whence -a' with these combinations:
* a function, built-in and external command
* an undefined/autoload function, built-in and external command
Fixes https://github.com/ksh93/ksh/issues/83
This commit fixes two different crashes related to kshdb:
- When redirect is given an invalid file descriptor, a segfault
no longer occurs. Reproducer:
$ ksh -c 'redirect 9>&200000000000'
- Fix a crash due to free(3) being used on an invalid pointer.
This can be reproduced with kshdb (commands from att/ast#582):
$ git clone https://github.com/rocky/kshdb.git
$ cd kshdb
$ ksh autogen.sh
$ echo "print hi there" > $HOME/.kshdbrc
$ ./kshdb -L . test/example/dbg-test1.sh
src/cmd/ksh93/bltins/misc.c: b_dot_cmd():
- The string pointed to by shp->st.filename must be able to be
freed from memory with free(3), so duplicate the string with
strdup(3).
src/cmd/ksh93/sh/io.c: sh_redirect():
- Show an error message when a file descriptor is invalid to
fix a memory fault.
Commit 80d9ae2b removed the line that set the NV_EXPORT flag on an
alias when the obsolete ksh88 'alias -x' option was used. But it
turns out that flag actually did something: it caused 'whence -v'
to report the alias as an exported alias -- misleadingly, because
exported aliases have never actually exised in ksh93. Since '-x' no
longer sets that flag, that message is never printed.
src/cmd/ksh93/data/msg.c,
src/cmd/ksh93/include/path.h:
- Remove is_xalias[] = "%s is an exported alias for " message.
src/cmd/ksh93/bltins/whence.c:
- Remove dead code to check for (formerly) exported alias.
The coshell(1) command, which is required for libcoshell to be
useful, is not known to be shipped by any distribution. It was
removed by the ksh-community fork and hence also by 93u+m (in
2940b3f5). The coshell facility as a whole is obsolete and
insecure. For a long time now, the statically linked libcoshell
library has been 40+ kilobytes of dead weight in the ksh binary.
Prior discussion (ksh2020): https://github.com/att/ast/issues/619
src/lib/libcoshell/*:
- Removed.
src/cmd/ksh93/*:
- Remove the SHOPT_COSHELL compiler option (which was enabled) and
a lot of code that was conditional upon #ifdef SHOPT_COSHELL.
- init.c: e_version[]: Removing SHOPT_COSHELL changed the "J"
feature identifier in ${.sh.version} to a lowercase "j", which
was conditional upon SHOPT_BGX (background job extensions).
But src/cmd/ksh93/RELEASE documents (at 08-12-04, on line 1188):
| +SHOPT_BGX enables background job extensions. Noted by "J" in
| the version string when enabled. [...]
That is the only available documentation. So change that "j" back
to a "J", leaving the version string unchanged after this commit.
- jobs.c: job_walk(): We need to keep one 'job_waitsafe(SIGCHLD);'
call that was conditional upon SHOPT_COSHELL; removing it caused
a regression test failure in tests/sigchld.sh, 'SIGCHLD blocked
for script at end of pipeline' (which means that until now, a ksh
compiled without libcoshell had broken SIGCHLD handling.)
bin/package, src/cmd/INIT/package.sh:
- Don't export COSHELL variable.
Support for the long-dead 3DFS userland versioning file system was
already removed from ksh93 (although I'd overlooked some minor
things), but libast still supported it. This removes that too.
src/lib/libast/include/fs3d.h,
src/lib/libast/man/fs3d.3,
src/lib/libast/misc/fs3d.c:
- Removed.
bin/package,
src/cmd/INIT/package.sh:
- Remove attempted use of removed vpath builtin.
src/cmd/ksh93/*:
- Remove minor 3dfs vestiges.
src/lib/lib{ast,cmd,coshell}/*:
- Remove code supporting 3dfs.
This commit backports the main changes to sh_delay from ksh93v-
and ksh2020, which fixes the following bugs:
- Microsecond amounts of less than one millisecond are no longer
ignored. The following loop will now take a minimum of one
second to complete:
for ((i = 0; i != 10000; i++)) do
sleep PT100U
done
- 'sleep 30' no longer adds an extra 30 milliseconds to the total
amount of time to sleep. This bug is hard to notice since 30
milliseconds can be considered within the margin of error. The
only reason why longer delays weren't affected is because the old
code masked the bug when the interval is greater than 30 seconds:
else if(n > 30)
{
sleep(n);
t -= n;
}
This caused 'sleep -s' to break with intervals greater than 30
seconds, so an actual fix is used instead of a workaround.
- 'sleep -s' now functions correctly with intervals of more than
30 seconds as the new code doesn't need the old workaround. This
is done by handling '-s' in sh_delay.
src/cmd/ksh93/bltins/sleep.c:
- Remove the replacement for sleep(3) from the sleep builtin.
- Replace the old sh_delay function with the newer one from ksh2020.
The new function uses tvsleep, which uses nanosleep(3) internally.
src/cmd/ksh93/include/shell.h,
src/cmd/ksh93/edit/edit.c,
src/cmd/ksh93/sh/jobs.c,
src/cmd/ksh93/sh/xec.c,
src/cmd/ksh93/shell.3:
- Update sh_delay documentation and usage since the function now
requires two arguments.
src/cmd/ksh93/tests/builtins.sh:
- Add a regression test for 'sleep -s' when the interval is greater
than 30 seconds. The other bugs can't be tested for in a feasible
manner across all systems:
https://github.com/ksh93/ksh/pull/72#issuecomment-657215616
With this change no more preset aliases exist, so the preset alias
tables can be safely removed. All ksh commands can now be used
without 'unalias -a' removing them, even in interactive shells.
Additionally, the history and r commands are no longer limited to
being used in interactive shells.
src/cmd/ksh93/bltins/hist.c:
- Implement the history and r commands as builtins. Also guarantee
lflag is set to one by avoiding 'lflag++'.
src/cmd/ksh93/Makefile,
src/cmd/ksh93/Mamfile,
src/cmd/ksh93/sh/main.c,
src/cmd/ksh93/sh/init.c,
src/cmd/ksh93/data/aliases.c:
- Remove the table of predefined aliases because the last few have
been removed. During init the alias tree is now initialized the
same way as the function tree.
src/cmd/ksh93/bltins/typeset.c:
- Remove the bugfix for unsetting predefined aliases because it is
now a no-op. Aliases are no longer able to have the NV_NOFREE
attribute.
src/cmd/ksh93/tests/alias.sh:
- Remove the regression test for unsetting predefined aliases since
those no longer exist.
src/cmd/ksh93/data/builtins.c:
- Update sh_opthist[] for 'hist --man', etc.
src/cmd/ksh93/sh.1:
- Remove the list of preset aliases since those no longer exist.
- Document history and r as builtins instead of preset aliases.
Co-authored-by: Martijn Dekker <martijn@inlv.org>
These two default aliases are useful on interactive shells. In
scripts, they interfere with possible function or command names.
As of this commit, these final two default aliases are only loaded
for interactive shells, leaving zero default aliases for scripts.
This completes the project to get rid of misguided default aliases.
src/cmd/ksh93/include/shtable.h,
src/cmd/ksh93/data/aliases.c:
src/cmd/ksh93/sh/init.c:
- Add empty alias table shtab_noaliases[] for scripts.
- Rename inittree() to sh_inittree() and make it external.
- nv_init(), sh_reinit(): Initialise empty alias tree for scripts.
src/cmd/ksh93/sh/main.c: sh_main():
- If interactive, reinitialise alias tree for interactive shells.
src/cmd/ksh93/tests/alias.sh:
- To test default alias removal, launch shell with -i.
This converts the 'autoload', 'compound', 'float', 'functions',
'integer' and 'nameref' default aliases into regular built-in
commands, so that 'unalias -a' does not remove them. Shell
functions can now use these names, which improves compatibility
with POSIX shell scripts.
src/cmd/ksh93/data/aliases.c:
- Remove default typeset aliases.
src/cmd/ksh93/data/builtins.c,
src/cmd/ksh93/include/builtins.h:
- Add corresponding built-in command declarations. Typeset-style
commands are now defined by a pointer range, SYSTYPESET ..
SYSTYPESET_END. A couple need their own IDs (SYSCOMPOUND,
SYSNAMEREF) for special-casing in sh/xec.c.
- Update 'typeset --man'.
src/cmd/ksh93/bltins/typeset.c: b_typeset():
- Recognise the new builtin commands by argv[0]. Implement them by
inserting the corresponding 'typeset' options into the argument
list before parsing options. This may seem like a bit of a hack,
but it is simpler, shorter, more future-proof and less
error-prone than manually copying and adapting all the complex
flaggery from the option parsing loop.
src/cmd/ksh93/sh/parse.c,
src/cmd/ksh93/sh/xec.c:
- Recognise typeset-style commands by SYSTYPESET .. SYSTYPESET_END
pointer range.
- Special-case 'compound' (SYSCOMPOUND) and 'nameref' (SYSNAMEREF)
along with recognising the corresponding 'typeset' options.
src/cmd/ksh93/sh.1:
- Update to document the new built-ins.
- Since not all declaration commands are special built-ins now,
identify declaration commands using a double-dagger "\(dd"
character (which renders as '=' in ASCII) and disassociate their
definition from that of special built-ins.
src/cmd/ksh93/tests/variables.sh:
- Adapt a regression test as there is no more 'integer' alias.
'set -b' had no effect; it should cause the shell to notify job
state changes immediately instead of waiting for the next prompt.
This fixes a regression that was introduced in ksh93t 2008-07-25.
The bugfix is from: https://github.com/att/ast/pull/1089
src/cmd/ksh93/sh/jobs.c:
- Save the tty wait state and avoid changing it if TTYWAIT was
already on to avoid breaking 'set -b'.
The last 'sh_offstate' is inside of an '#if' directive because it
is only required when ksh is compiled with SHOPT_COSHELL enabled.
src/cmd/ksh93/tests/pty.sh:
- Add a regression test for 'set -b' in interactive shells.
Type names that start with a lowercase 'a' cause an error when used:
$ typeset -T al=(typeset bar)
$ al foo=(bar=testset)
/usr/bin/ksh: al: : invalid variable name
The error occurs because when the parser checks for the alias
builtin (to set 'assignment' to two instead of one), only the first
letter of 'argp->argval' is checked (rather than the entire
string). This was fixed in ksh93v- by comparing argp->argval
against "alias", but in ksh93u+m the check can simply be removed
because it is only run when a builtin has the BLT_DCL flag. As of
04b9171, the alias builtin does not have that flag.
src/cmd/ksh93/sh/parse.c:
- Remove the bugged check for the alias builtin.
src/cmd/ksh93/tests/types.sh:
- Add a regression test for type names starting with a lowercase 'a'.
There is a bug in sh_eval() that may cause ksh to crash due to a
double free() after sourcing multiple files with '.' or 'source'
if a longjmp is triggered, e.g. by a syntax error.
This applies a fix from Siteshwar Vashist:
https://www.mail-archive.com/ast-developers@lists.research.att.com/msg01943.html
src/cmd/ksh93/sh/xec.c: sh_eval():
- Zero file descriptor io_save after closing it. This prevents a
double free() after returning from a longjmp.
src/cmd/ksh93/tests/basic.sh:
- Add reproducer as regression test.
This commit changes the behavior of four date formats accepted
by 'printf %()T' because the old behavior is not compatible with
modern implementations of date(1):
- %k and %l now return a blank-padded hour, the former based on a
24-hour clock and the latter a 12-hour clock (these are common
extensions present on Linux and *BSD).
- %f now returns a date with the format '%Y.%m.%d-%H:%M:%S'
(BusyBox extension).
- %q now returns the quarter of the current year (GNU extension).
src/cmd/ksh93/data/builtins.c:
- Copy the date format documentation from date in libcmd to
the printf man page (for documenting 'printf %T').
src/cmd/ksh93/tests/builtins.sh:
- Add four regression tests for the changed date formats.
src/cmd/ksh93/sh.1:
- Remove inaccurate information about the date formats accepted by
printf %T'. The KornShell uses a custom version of strftime(3)
that isn't guaranteed to accepts the same formats as the native
strftime function.
src/lib/libast/tm/tmxfmt.c:
- Change the behavior of %f, %k, %l and %q to the common behavior.
%k and %l are implemented as aliases to %_H and %_I to avoid
duplicating code.
src/lib/libcmd/date.c:
- Update the documentation for the AST date command since it is
also affected by the changes to 'printf %T'.
Fixes#62
The following set of commands can rarely cause a memory fault
when auditing[*] is enabled, although most of the time it will
simply cause ksh to write '(null)' to the auditing file in place
of a tty name:
$ [ -e /etc/ksh_audit ] || echo "/tmp/ksh_auditfile;$(id -u)" | sudo tee /etc/ksh_audit;
$ v=$(ksh 2> /dev/null +o rc -ic $'getopts a:bc: opt --man\nprint $?')
$ cat /tmp/ksh_auditfile
1000;1593599493;(null); getopts a:bc: opt --man
This happens because strdup is used unconditionally on the pointer
returned by 'ttyname', which can be NULL if stderr is closed. This
then causes 'hp->tty' to be set to null, as strdup returns NULL.
See https://github.com/att/ast/issues/1028
src/cmd/ksh93/edit/history.c:
- Make strdup duplicate 'notty' instead of NULL to prevent
crashes.
[*] https://blog.fpmurphy.com/2008/12/ksh93-auditing-and-accounting.html
If the processing of a multibyte character was interrupted in UTF-8
locales, e.g. by reading just one byte of a two-byte character 'ü'
(\303\274) with a command like:
print -nr $'\303\274' | read -n1 g
then the shellquoting algorithm was corrupted in such a way that
the final quote in simple single-quoted string was missing. This
bug may have had other, as yet undiscovered, effects as well. The
problem was with corrupted multibyte character processing and not
with the shell-quoting routine sh_fmtq() itself.
Full trace and discussion at: https://github.com/ksh93/ksh/issues/5
(which is also an attempt to begin to understand the esoteric
workings of the libast mb* macros that process UTF-8 characters).
src/lib/libast/comp/setlocale.c: utf8_mbtowc():
- If called from the mbinit() macro (i.e. if both pointer
parameters are null), reset the global multibyte character
synchronisation state variable. This fixes the problem with
interrupted processing leaving an inconsistent state, provided
that mbinit() is called before processing multibyte characters
(which it is, in most (?) places that do this). Before this fix,
calling mbinit() in UTF-8 locales was a no-op.
src/cmd/ksh93/sh/string.c: sh_fmtq():
- Call mbinit() before potentially processing multibyte characters.
Testing suggests that this could be superfluous, but at worst,
it's harmless; better be sure.
src/cmd/ksh93/tests/builtins.sh:
- Add regression test for shellquoting with 'printf %q' after
interrupting the processing of a multibyte characeter with
'read -n1'. This test only fails in a UTF-8 locale, e.g. when
running: bin/shtests -u builtins SHELL=/buggy/ksh-2012-08-01
Fixes#5.
ksh crashed if it encountered a .paths directory in any of the
directories in $PATH.
Ref: https://bugs.launchpad.net/ubuntu/+source/ksh/+bug/1534855
src/cmd/ksh93/sh/path.c: path_chkpaths():
- Refuse to read .paths if it's not a regular file
or a symlink to a regular file.
File descriptors that are too far out of range will cause the
read builtin to crash. The following example will generate
two crashes:
$ ksh -c 'read -u 2000000' || ksh -c 'read -u-2000000'
The fix is to error out when the given file descriptor is out
of range. This bugfix is from Tomas Klacko, although it was
modified to use 'sh_iovalidfd' and reject numbers greater
than 'INT_MAX':
https://www.mail-archive.com/ast-developers@lists.research.att.com/msg01912.html
The question about 'shp->fdstatus[-1]' only applies to ksh93v-
(ksh93u+ doesn't have any references to 'shp->fdstatus[-1]').
src/cmd/ksh93/bltins/read.c:
- File descriptors that are out of range should be rejected
with an error message (like invalid file descriptors that
are in range). The seemingly redundant check for negative
numbers is there because out of range negative numbers also
cause memory faults despite the later 'fd<0' check.
src/cmd/ksh93/tests/io.sh:
- Add three tests for attempting 'read -u' on various invalid
file descriptor numbers.
Variables created with 'typeset -RF' were being treated as
short integers, even though they are actually floating point
values. As a result the following example will cause a crash:
$ typeset -RF foo=1
$ test "$foo"
This is fixed by checking for 'NV_DOUBLE' with 'nv_isattr',
which prevents ksh from treating floating point values as
short integers due to '== NV_INT16P' excluding 'NV_DOUBLE'.
This bugfix was backported from ksh93v- 2013-10-10-alpha.
src/cmd/ksh93/sh/array.c,
src/cmd/ksh93/sh/name.c,
src/cmd/ksh93/sh/nvdisc:
- Avoid treating floating point values as short integers by
checking for 'NV_DOUBLE' with 'nv_isattr'.
src/cmd/ksh93/tests/types.sh:
- Add a regression test for the 'typeset -RF' crash. The
crash cannot be replicated if 'typeset -RF' sets 'foo'
to zero.
The cd builtin was removing '.' from directory names when combined
with a preceding '../', which caused commands like 'cd ../.local'
to become 'cd ../local'. This patch fixes the problem by limiting
the extra handling to leading '..'. The bugfix comes from ksh93v-
2013-10-10-alpha, although this version is a shortened patch from
Solaris (as ksh93v- refactored a decent amount of the code for the
cd builtin).
src/cmd/ksh93/bltins/cd_pwd.c:
- cd should only check for leading '..', as trying to handle a lone
'.' only causes problems.
src/cmd/ksh93/tests/builtins.sh:
- Add a regression test for this problem based on the test present in
ksh93v- 2013-10-10-alpha.
Patch from Solaris:
https://github.com/oracle/solaris-userland/blob/860d27f/components/ksh93/patches/270-23319761.patch
This commit fixes the bug reported in:
https://github.com/att/ast/issues/682
The following sequence fails in vi mode because ksh looks in the
wrong part of the 'virtual' buffer:
$ touch ~/testfile
$ ls ~/test<tab>
The fix is to change 'virtual[i]' to 'virtual[last_virt]' in the
bugged section of code. The other changes are to make sure listing
files in a directory with something like 'ls /etc/<tab>' calls the
code for Ctrl+L to preserve 'ls /etc/' rather than try (and fail)
to complete the directory name, producing 'ls /etc\n/'. This bugfix
was backported from ksh93v- 2013-10-10-alpha.
src/cmd/ksh93/edit/vi.c
- Backport the bugfix from ksh93v- 2013-10-10-alpha for this
problem.
src/cmd/ksh93/tests/pty.sh
- Add a regression test for this issue using pty, adjusted slightly
for a fake home directory in /tmp.
The code for handling process substitution with redirection was
never being run because IORAW is usually set when IOPROCSUB is
set. This commit fixes the problem by moving the required code
out of the !IORAW if statement. The following command now prints
'good' instead of writing 'ok' to a bizzare file:
$ ksh -c 'echo ok > >(sed s/ok/good/); wait'
good
This commit also fixes a bug that caused the process ID of the
asynchronous process to print when the shell was in interactive
mode. The following command no longer prints a process ID,
behaving like in Bash and zsh:
$ echo >(true)
/dev/fd/5
src/cmd/ksh93/sh/args.c:
- Temporarily turn off the interactive state while in a process
substitution to prevent the shell from printing the PID of
the asynchronous process.
src/cmd/ksh93/sh/io.c:
- Move the code for process substitution with redirection into
a separate if statement.
src/cmd/ksh93/tests/io.sh:
- Add two tests for both process substitution bugs fixed by this
commit.
src/cmd/ksh93/tests/shtests:
- Update shtests with a patch from Martijn Dekker to use
pretty-printing for the output from the times builtin (if it
is available).
Fixes#2
Ksh was trying to use the 'pw' variable as a valid pointer even
when it was NULL. This is fixed by doing the error check for
'pw' before doing anything else in 'job_kill'.
This bugfix is from Red Hat:
44e0a643a9/f/SOURCES/ksh-20130214-fixkill.patchFixes#34
The 'stop' and 'suspend' default aliases are now converted into
regular built-in commands so that 'unalias -a' does not remove
them, 'suspend' can do some sanity checks, and something like
cmd=stop; $cmd $!
will now work.
src/cmd/ksh93/bltins/trap.c:
- b_kill(): Incorporate 'stop' functionality, which is simply
setting the same flag and variable as '-s STOP' would have done.
- b_suspend(): Add simple builtin function that sends SIGSTOP to
the main shell. Check for no operands, and refuse to suspend a
login shell (which would leave the user stuck with no way out).
Also check that 'kill' succeeds; if we're in an asynchronous
subshell, it is possible the main shell no longer exists.
src/cmd/ksh93/data/aliases.c:
- Remove "stop" and "suspend" default aliases. (Why were these
conditional upon SIGTSTP when they actually issued SIGSTOP?)
src/cmd/ksh93/include/builtins.h,
src/cmd/ksh93/data/builtins.c,
src/cmd/ksh93/data/msg.c:
- Add declarations of "stop" and "suspend" regular built-ins.
- Add option strings (AST manual/--man pages) for them.
- Add e_toomanyops ("too many operands") reusable error message for
b_suspend(). Other new commands may want this at some point.
src/cmd/ksh93/sh.1:
- Remove "stop" and "suspend" default aliases.
- Document "stop" and "suspend" regular built-in commands.
src/cmd/ksh93/data/variables.c:
- Running 'unset .sh.lineno' creates a memory fault, so fix that
by giving it the NV_NOFREE attribute. This crash was happening
because ${.sh.lineno} is an integer that cannot be freed from
memory with free(3).
src/cmd/ksh93/sh/init.c:
- Tell _nv_unset to ignore NV_RDONLY when $RANDOM and $LINENO are
restored from the subshell scope. This is required to fully
restore the original state of these variables after a virtual
subshell finishes.
src/cmd/ksh93/bltins/typeset.c,
src/cmd/ksh93/sh/subshell.c:
- Disabled some optimizations for two instances of 'sh_assignok' to
fix 'readonly' in virtual subshells and '(unset .sh.level)' in
nested functions. This fixes the following variables when
'(readonly $varname); enum varname=' is run:
$_
${.sh.name}
${.sh.subscript}
${.sh.level}
The optimization in question prevents sh_assignok from saving the
original state of these variables by making the sh_assignok call
a no-op. Ksh needs the original state of a variable for it to be
properly restored after a virtual subshell has run, otherwise ksh
will simply carry over any new flags (being NV_RDONLY in this case)
from the subshell into the main shell.
src/cmd/ksh93/tests/variables.sh:
- Add regression tests from Martijn Dekker for setting special
variables as readonly in virtual subshells and for unsetting
special variables in general.
Fixes#4
