Most of these changes remove unused variables, functions and labels
to fix -Wunused compiler warnings. Somewhat notable changes:
src/cmd/ksh93/bltins/print.c:
- Removed the unused 'neg' variable.
Patch from ksh2020: https://github.com/att/ast/pull/725
src/cmd/ksh93/bltins/sleep.c:
- Initialized ns to fix three -Wsometimes-uninitialized warnings.
src/cmd/ksh93/edit/{emacs,vi}.c:
- Adjust strncpy size to fix two -Wstringop-truncation warnings.
src/cmd/ksh93/include/shell.h:
- The NOT_USED macro caused many -Wunused-value warnings,
so it has been replaced with ksh2020's macro:
19d0620a
src/cmd/ksh93/sh/expand.c:
- Removed an unnecessary 'ap = ' since 'ap' is never read
between stakseek and stakfreeze.
src/cmd/ksh93/edit/vi.c: refresh():
- Undef this function's 'w' macro at the end of it to stop it
potentially interfering with future code changes.
src/cmd/ksh93/sh/nvdisc.c,
src/lib/libast/misc/magic.c,
src/lib/libast/regex/regsubexec.c,
src/lib/libast/sfio/sfpool.c,
src/lib/libast/vmalloc/vmbest.c:
- Fixed some indentation to silence -Wmisleading-indentation
warnings.
src/lib/libast/include/ast.h:
- For clang, now only suppress hundreds of -Wparentheses warnings
as well as a few -Wstring-plus-int warnings.
Clang's -Wparentheses warns about things like
if(foo = bar())
which assigns to foo and checks the assigned value.
Clang wants us to change this into
if((foo = bar()))
Clang's -Wstring-plus-int warns about things like
"string"+x
where x is an integer, e.g. "string"+3 represents the string
"ing". Clang wants us to change that to
"string"[3]
The original versions represent a perfectly valid coding style
that was common in the 1980s and 1990s and is not going to change
in this historic code base. (gcc does not complain about these.)
Co-authored-by: Martijn Dekker <martijn@inlv.org>
Huge typeset -L/-R adjustment length values were still causing
crashses on sytems with not enough memory. They should error out
gracefully instead of crashing.
This commit adds out of memory checks to all malloc/calloc/realloc
calls that didn't have them (which is all but two or three).
The stkalloc/stakalloc calls don't need the checks; it has
automatic checking, which is done by passing a pointer to the
outofspace() function to the stakinstall() call in init.c.
src/lib/libast/include/error.h:
- Change the ERROR_PANIC exit status value from ERROR_LEVEL (255)
to 77, which is what it is supposed to be according to the libast
error.3 manual page. Exit statuses > 128 for anything else than
signals are not POSIX compliant and may cause misbehaviour.
src/cmd/ksh93/include/defs.h,
src/cmd/ksh93/sh/init.c:
- To facilitate consistency, add a simple extern sh_outofmemory()
function that throws an ERROR_PANIC "out of memory".
src/cmd/ksh93/include/shell.h,
src/cmd/ksh93/data/builtins.c:
- Remove now-redundant e_nospace[] extern message; it is now only
used in one place so it might as well be a string literal in
sh_outofmemory().
All other changed files:
- Verify the result of all malloc/calloc/realloc calls and call
sh_outofmemory() if they fail.
Many of the errors fixed in this commit are word repetitions
such as 'the the' and minor spelling errors. One formatting
error in the ksh man page has also been fixed.
This commit fixes a bug in the 'read' built-in: it did not properly
skip over multibyte characters. The bug never affects UTF-8 locales
because all UTF-8 bytes have the high-order bit set. But Shift-JIS
characters may include a byte corresponding to the ASCII backslash
character, which cauased buggy behaviour when using 'read' without
the '-r' option that disables backslash escape processing.
It also makes the regression tests compatible with Shift-JIS
locales. They failed with syntax errors.
src/cmd/ksh93/bltins/read.c:
- Use the multibyte macros when skipping over word characters.
Based on a patch from the old ast-developers mailing list:
https://www.mail-archive.com/ast-developers@lists.research.att.com/msg01848.html
src/cmd/ksh93/include/defs.h:
- Be a bit smarter about causing the compiler to optimise out
multibyte code when SHOPT_MULTIBYTE is disabled. See the updated
comment for details.
src/cmd/ksh93/tests/locale.sh:
- Put all the supported locales in an array for future tests.
- Add test for the 'read' bug. Include it in a loop that tests
64 SHIFT-JIS character combinations. Only one fails on old ksh:
the one where the final byte corresponds to the ASCII backslash.
It doesn't hurt to test all the others anyway.
src/cmd/ksh93/tests/basic.sh,
src/cmd/ksh93/tests/builtins.sh,
src/cmd/ksh93/tests/quoting2.sh:
- Fix syntax errors that occurred in SHIFT-JIS locales as the
parser was processing literal UTF-8 characters. Not executing
that code is not enough; we need to make sure it never gets
parsed as well. This is done by wrapping the commands containing
literal UTF-8 strings in an 'eval' command as a single-quoted
operand.
.github/workflows/ci.yml:
- Run the tests in the ja_JP.SJIS locale instead of ja_JP.UTF-8.
UTF-8 is already covered by the nl_NL.UTF-8 test run; that should
be good enough.
This fixes the following:
1. 'set --posix' now works as an equivalent of 'set -o posix'.
2. The posix option turns off braceexpand and turns on letoctal.
Any attempt to override that in a single command such as 'set -o
posix +o letoctal' was quietly ignored. This now works as long
as the overriding option follows the posix option in the command.
3. The --default option to 'set' now stops the 'posix' option, if
set or unset in the same 'set' command, from changing other
options. This allows the command output by 'set +o' to correctly
restore the current options.
src/cmd/ksh93/data/builtins.c:
- To make 'set --posix' work, we must explicitly list it in
sh_set[] as a supported option so that AST optget(3) recognises
it and won't override it with its own default --posix option,
which converts the optget(3) string to at POSIX getopt(3) string.
This means it will appear as a separate entry in --man output,
whether we want it to or not. So we might as well use it as an
example to document how --optionname == -o optionname, replacing
the original documentation that was part of the '-o' description.
src/cmd/ksh93/sh/args.c: sh_argopts():
- Add handling for explitit --posix option in data/builtins.c.
- Move SH_POSIX syncing SH_BRACEEXPAND and SH_LETOCTAL from
sh_applyopts() into the option parsing loop here. This fixes
the bug that letoctal was ignored in 'set -o posix +o letoctal'.
- Remember if --default was used in a flag, and do not sync options
with SH_POSIX if the flag is set. This makes 'set +o' work.
src/cmd/ksh93/include/argnod.h,
src/cmd/ksh93/data/msg.c,
src/cmd/ksh93/sh/args.c: sh_printopts():
- Do not potentially translate the 'on' and 'off' labels in 'set
-o' output. No other shell does, and some scripts parse these.
src/cmd/ksh93/sh/init.c: sh_init():
- Turn on SH_LETOCTAL early along with SH_POSIX if the shell was
invoked as sh; this makes 'sh -o' and 'sh +o' show expected
options (not that anyone does this, but correctness is good).
src/cmd/ksh93/include/defs.h,
src/cmd/ksh93/include/shell.h:
- The state flags were in defs.h and most (but not all) of the
shell options were in shell.h. Gather all the shell state and
option flag definitions into one place in shell.h for clarity.
- Remove unused SH_NOPROFILE and SH_XARGS option flags.
src/cmd/ksh93/tests/options.sh:
- Add tests for these bugs.
src/lib/libast/misc/optget.c: styles[]:
- Edit default optget(3) option self-documentation for clarity.
Several changed files:
- Some SHOPT_PFSH fixes to avoid compiling dead code.
With this patch, the Korn shell can now guarantee that calls to
sleep on systems using the select or poll method always result in
the system clock advancing by that much time, assuming no
interruptions. This compensates for deficiencies in certain
systems, including SCO UnixWare.
Discussion: https://github.com/ksh93/ksh/pull/174
src/lib/libast/tm/tvsleep.c:
- Ensure that at least the time requested to sleep has elapsed
for the select and poll methods.
- Simplify the logic of calculating the time remaining to
sleep and handle the case of an argument of greater than
10e9 nanoseconds being passed to tvsleep.
src/cmd/ksh93/bltins/sleep.c:
- Eliminate the check for EINTR to handle other cases wherein
we have not slept enough.
src/cmd/ksh93/tests/variables.sh:
- Improve the diagnostic message when the sleep test fails.
- Revise the SECONDS function test to expect that we always
sleep for at least the time specified.
src/cmd/ksh93/tests/functions.h:
- Redirect ps stderr to /dev/null. UnixWare ps prints an error
message about not being able to find the controlling terminal
when shtests output is piped, but we are only using ps to find
the PID.
If I haven't missed anything, this should make the non-interactive
aspects of job control in scripts work as expected, except for the
"<command unknown>" issue in the output of 'bg', 'fg' and 'jobs'
(which is not such a high priority as those commands are really
designed for interactive use).
Plus, I believe I now finally understand what these three are for:
* The job.jobcontrol variable is set to nonzero by job_init() in
jobs.c if, and only if, the shell is interactive *and* managed to
get control of the terminal. Therefore, any changing of terminal
settings (tcsetpgrp(3), tty_set()) should only be done if
job.jobcontrol is nonzero. This commit changes several checks for
sh_isoption(SH_INTERACTIVE) to checks for job.jobcontrol for
better consistency with this.
* The state flag, sh_isstate(SH_MONITOR), determines whether the
bits of job control that are relevant for both scripts and
interactive shells are active, which is mostly making sure that a
background job gets its own process group (setpgid(3)).
* The shell option, sh_isoption(SH_MONITOR), is just that. When the
user turns it on or off, the state flag is synched with it. It
should usually not be directly checked for, as the state may be
temporarily turned off without turning off the option.
Prior discussion:
https://www.mail-archive.com/austin-group-l@opengroup.org/msg06456.html
src/cmd/ksh93/bltins/typeset.c, src/cmd/ksh93/sh/args.c:
- Move synching the SH_MONITOR state flag with the SH_MONITOR
shell option from b_set() (the 'set' builtin) to sh_applyopts()
which is indirectly called from b_set() and is also used when
parsing the shell invocation command line. This ensures -m is
properly enabled in both scenarios.
src/cmd/ksh93/sh/jobs.c:
- job_init(): Do not refuse to initialise job control on
non-interactive shells. Instead, skip everything that should only
be done on interactive shells (i.e., everything to do with the
terminal). This function is now even more of a mess than it was
before, so refactoring may be desirabe at some point.
- job_close(), job_set(), job_reset(), job_wait(): Do not reset the
terminal process group (tcsetpgrp()) if job.jobcontrol isn't on.
src/cmd/ksh93/sh/xec.c:
- sh_exec(): TFORK: For SIGINT handling, check the SH_MONITOR
state flag, not the shell option.
- sh_exec(): TFORK: Do not turn off the SH_MONITOR state flag in
forked children. The non-interactive part of job control should
stay active. Instead, turn off the SH_INTERACTIVE state flag so
we don't get interactive shell behaviour (i.e. job control noise
on the terminal) in forked subshells.
- _sh_fork(), sh_ntfork(): Do not reset the terminal process group
(tcsetpgrp()) if job.jobcontrol isn't on. Do not turn off the
SH_MONITOR state flag in forked children.
src/cmd/ksh93/sh/subshell.c: sh_subfork():
- Do not turn off the monitor option and state in forked subshells.
The non-interactive part of job control should stay active.
src/cmd/ksh93/bltins/misc.c: b_bg():
- Check isstate(SH_MONITOR) instead of sh_isoption(SH_MONITOR) &&
job.jobcontrol before throwing a 'no job control' error.
This fixes a minor bug: fg, bg and disown could quietly fail.
src/cmd/ksh93/tests/jobs.sh:
- Add tests for 'fg' with job control IDs (%%, %1) in scripts.
- Add test checking that a background job launched from a subsell
with job control enabled correctly becomes the leader of its own
process group.
Makes progress on: https://github.com/ksh93/ksh/issues/119
src/cmd/ksh93/bltins/enum.c:
- enum_type[]: Fix typos; minor edit for style.
- enum_type[], enuminfo(): Make the list of supported values
comma-separated, instead of using a comma at the start of each.
src/cmd/ksh93/sh/nvtype.c:
- sh_opttype[]: Fix typos.
Many compile-time options were broken so that they could not be
turned off without causing compile errors and/or regression test
failures. This commit now allows the following to be disabled:
SHOPT_2DMATCH # two dimensional ${.sh.match} for ${var//pat/str}
SHOPT_BGX # one SIGCHLD trap per completed job
SHOPT_BRACEPAT # C-shell {...,...} expansions (, required)
SHOPT_ESH # emacs/gmacs edit mode
SHOPT_HISTEXPAND # csh-style history file expansions
SHOPT_MULTIBYTE # multibyte character handling
SHOPT_NAMESPACE # allow namespaces
SHOPT_STATS # add .sh.stats variable
SHOPT_VSH # vi edit mode
The following still break ksh when disabled:
SHOPT_FIXEDARRAY # fixed dimension indexed array
SHOPT_RAWONLY # make viraw the only vi mode
SHOPT_TYPEDEF # enable typeset type definitions
Compiling without SHOPT_RAWONLY just gives four regression test
failures in pty.sh, but turning off SHOPT_FIXEDARRAY and
SHOPT_TYPEDEF causes compilation to fail. I've managed to tweak the
code to make it compile without those two options, but then dozens
of regression test failures occur, often in things nothing directly
to do with those options. It looks like the separation between the
code for these options and the rest was never properly maintained.
Making it possible to disable SHOPT_FIXEDARRAY and SHOPT_TYPEDEF
may involve major refactoring and testing and may not be worth it.
This commit has far too many tweaks to list. Notables fixes are:
src/cmd/ksh93/data/builtins.c,
src/cmd/ksh93/data/options.c:
- Do not compile in the shell options and documentation for
disabled features (braceexpand, emacs/gmacs, vi/viraw), so the
shell is not left with no-op options and inaccurate self-doc.
src/cmd/ksh93/data/lexstates.c:
- Comment the state tables to associte them with their IDs.
- In the ST_MACRO table (sh_lexstate9[]), do not make the S_BRACE
state for position 123 (ASCII for '{') conditional upon
SHOPT_BRACEPAT (brace expansion), otherwise disabling this causes
glob patterns of the form {3}(x) (matching 3 x'es) to stop
working as well -- and that is ksh globbing, not brace expansion.
src/cmd/ksh93/edit/edit.c: ed_read():
- Fixed a bug: SIGWINCH was not handled by the gmacs edit mode.
src/cmd/ksh93/sh/name.c: nv_putval():
- The -L/-R left/right adjustment options to typeset do not count
zero-width characters. This is the behaviour with SHOPT_MULTIBYTE
enabled, regardless of locale. Of course, what a zero-width
character is depends on the locale, but control characters are
always considered zero-width. So, to avoid a regression, add some
fallback code for non-SHOPT_MULTIBYTE builds that skips ASCII
control characters (as per iscntrl(3)) so they are still
considered to have zero width.
src/cmd/ksh93/tests/shtests:
- Export the SHOPT_* macros from SHOPT.sh to the tests as
environment variables, so the tests can check for them and decide
whether or how to run tests based on the compile-time options
that the tested binary was presumably compiled with.
- Do not run the C.UTF-8 tests if SHOPT_MULTIBYTE is not enabled.
src/cmd/ksh93/tests/*.sh:
- Add a bunch of checks for SHOPT_* env vars. Since most should
have a value 0 (off) or 1 (on), the form ((SHOPT_FOO)) is a
convenient way to use them as arithmetic booleans.
.github/workflows/ci.yml:
- Make GitHub do more testing: run two locale tests (Dutch and
Japanese UTF-8 locales), then disable all the SHOPTs that we can
currently disable, recompile ksh, and run the tests again.
The >;word and <>;word redirection operators cannot be used with
the 'exec' builtin, but the 'redirect' builtin (which used to be
an alias of 'command exec') permitted them. However, they do not
have the documented effect of the added ';'. So this commit blocks
those operators for 'redirect' as they are blocked for 'exec'.
It also tweaks redirect's error message if a non-redirection
argument is encountered.
src/cmd/ksh93/sh/parse.c: simple():
- Set the lexp->inexec flag for SYSREDIR (redirect) as well as
SYSEXEC (exec). This flag is checked for in sh_lex() (lex.c) to
throw a syntax error if one of these two operators is used.
src/cmd/ksh93/sh.1, src/cmd/ksh93/data/builtins.c:
- Documentation tweaks.
src/cmd/ksh93/sh/xec.c, src/cmd/ksh93/bltins/misc.c:
- When 'redirect' gives an 'incorrect syntax' (e_badsyntax) error
message, include the first word that was found not to be a valid
redirection. This is simply the first argument, as redirections
are removed from the arguments list.
src/cmd/ksh93/tests/io.sh:
- Update test to reflect new error message format.
This commit corrects how shortint was being applied to various
possible typeset variables in error. The short integer option
modifier 'typeset -s' should only be able to be applied if the
the variable is also an integer. Several issues were resolved
with this fix:
- 'typeset -s': created a short integer having an invalid base
of zero. 'typeset -s foo' created 'typeset -s -i 0 foo=0' and
now will result in an empty string.
- 'typeset -sL': previously resulted in a segmentation fault.
The following are the various incorrect 'typeset' instances
that have been fixed:
$ 'export foo; typeset -s foo; readonly foo; typeset -p foo'
(before) typeset -x -r -s -i 0 foo=0
( after) typeset -x -r foo
$ 'typeset -sL foo=1*2; typeset -p foo'
(before) Segmentation fault (core dumped)
( after) typeset -L 3 foo='1*2'
$ 'typeset -sR foo=1*2; typeset -p foo'
(before) typeset -s -i foo=2
( after) typeset -R 3 foo='1*2'
$ 'typeset -sZ foo=1*2; typeset -p foo'
(before) typeset -F 0 foo=2
( after) typeset -Z 3 -R 3 foo='1*2'
src/cmd/ksh93/bltins/typeset.c: b_typeset():
- Add conditional check within the 's' option to only
apply NV_SHORT as well as remove any NV_LONG flag
if NV_INTEGER flag was set.
- Relocate shortint conditional logic to the 'i' option.
src/cmd/ksh93/tests/attributes.sh:
- Adjust regression tests for '-s' and add '-si' check.
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
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.
It is not correct to save sh.ifstable (a.k.a. shp->ifstable) before
calling a function and then restore it after; this can cause field
splitting to malfunction. See 70368c57.
The change to init.c in the Red Hat patch applied in 18b3f4aa
(shp->ifstable[0] = S_EOF) appears to be sufficient.
src/cmd/ksh93/bltins/alarm.c:
- Revert save/restore of sh.ifstable.
src/cmd/ksh93/tests/builtins.sh:
- Tweak the regression test to work correctly on a slower machine,
i.e. a Raspberry Pi running FreeBSD 12.2 arm64 (thanks to hyenias
for providing testing access).
This commit resolves the following incorrect variable assignments:
$ unset a; typeset -uF a=2; typeset -p a
typeset -X a=0x1.0000000000p+1
$ unset a; typeset -Fu a=2; typeset -p a
typeset -X a=0x1.0000000000p+1
$ unset a; typeset -ulF a=2; typeset -p a
typeset -l -X a=0x1.0000000000p+1
$ unset a; typeset -Ful a=2; typeset -p a
typeset -l -X a=0x1.0000000000p+1
$ unset a; typeset -Eu a=2; typeset -p a
typeset -E -X a=2
$ unset a; typeset -Eul a=2; typeset -p a
typeset -l -E -X a=2
src/cmd/ksh93/bltins/typeset.c:
- If the unsigned option (-u) was provided in conjunction with a
floating point (-F) then due to a flag collision with NV_UNSIGN
and NV_HEXFLOAT both having the value of NV_LTOU caused the
floating point to become a hexadecimal floating point (-X) in
error. Also, if a -E option flag was followed with a -u option
then the resulting variable would be both a scientific notation
and a hexadecimal floating point at the same time.
src/cmd/ksh93/tests/attributes.sh:
- Add regression tests.
Co-authored-by: Martijn Dekker <martijn@inlv.org>
This adds informative error messages if incompatible options are
given. It also documents the exclusive -m, -n and -T options on
separate usage lines, as was already done with -f. The usage
message for incompatible options now looks something like this:
| $ ksh -c 'typeset -L10 -F -f -i foo'
| ksh: typeset: -i/-F/-E/-X cannot be used with -L/-R/-Z
| ksh: typeset: -f cannot be used with other options
| Usage: typeset [-bflmnprstuxACHS] [-a[type]] [-i[base]] [-E[n]]
| [-F[n]] [-L[n]] [-M[mapping]] [-R[n]] [-X[n]]
| [-h string] [-T[tname]] [-Z[n]] [name[=value]...]
| Or: typeset -f [name...]
| Or: typeset -m [name=name...]
| Or: typeset -n [name=name...]
| Or: typeset -T [tname[=(type definition)]...]
| Help: typeset [ --help | --man ] 2>&1
(see also the previous commit, e21a053e)
Unfortunately the first "Usage" line has some redundancies with the
"Or:" lines showing separate usages. It doesn't seem to be possible
to avoid this; it's a flaw in how libast generates everything
(usage, help, manual) from one huge getopt(3) string. I still think
the three added "Or:" lines are an improvement as it wasn't
previously shown that these options need to be used on their own.
src/cmd/ksh93/bltins/typeset.c: b_typeset():
- Instead of only showing a generic usage message, add an
informative error message if incompatible options were given.
- Conflicting options detection was failing because NV_LJUST and
NV_EXPNOTE have the same bitmask value. Use a new 'isadjust'
flag for -L/-R/-Z to remember if one of these was set.
- Detect conflict between -L/-R/-Z and a float option, not just -i.
src/cmd/ksh93/include/name.h, src/cmd/ksh93/data/msg.c:
- Add the two new error messages for incompatible options.
src/cmd/ksh93/data/builtins.c: sh_opttypeset[]:
- Add a space after 'float' in in "[+float?\btypeset -lE\b]" as
this makes 'float' appear on its own line, improving formatting.
- Show -m, -n, -T on separate usage lines like -f, as none of these
can be combined with other options.
- Remove "cannot be combined with other options" from -m and -n
descriptions, as that should now be clear from the separate usage
lines -- and even if not, the error message is now informative.
src/cmd/ksh93/sh.1, src/cmd/ksh93/COMPATIBILITY:
- Update.
src/cmd/ksh93/tests/types.sh:
- Remove obsolete test: 'typeset -RF' is no longer accepted.
(It crashed in 93u+, so this is not an incompatibility...)
Resolves: https://github.com/ksh93/ksh/issues/48
src/cmd/ksh93/bltins/typeset.c:
- The new_argv[] array was one item too short (should be argc+2).
- Use AST stakalloc(3) to allocate it instead of a dynamic array;
this restores compatibility with ISO C90.
src/lib/libast/features/standards, src/cmd/INIT/cc.unixware.i386:
- Add support for UnixWare.
- Do not define any standards macros on this system, as on FreeBSD
and DragonFly BSD.
Commit d1483150 did not fully fix#153.
Test case from Harald van Dijk that was still failing:
$ mkdir test
$ cd test
$ rmdir $PWD
$ mkdir $PWD
$ ksh -c "(cd /); pwd"
/
Forking a virtual subshell in that case is needed to avoid ending
up in a directory that replaced the PWD, because it will not be
possible for a process to change back to the original directory.
src/cmd/ksh93/bltins/cd_pwd.c:
- When deciding whether to fork, instead of attempting to opendir
the PWD, compare the inodes $PWD and "." to determine if $PWD
still actually refers to the current directory. This uses the
test_inode() function which is also used by 'test foo -ef bar'.
src/cmd/ksh93/tests/subshell.sh:
- Add test based on the above.
Progresses: https://github.com/ksh93/ksh/issues/153
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
This change was pulled in from:
https://raw.githubusercontent.com/oracle/solaris-userland/master/components/ksh93/patches/185-Bug17714341.patch
No public information about the reasons for this change is
available, but it seems reasonable to trust that the Solaris people
found a legitimate need for it.
src/cmd/ksh93/bltins/cd_pwd.c: b_cd():
- When determining the old PWD before 'cd', do not trust shp->pwd
but get and validate the current PWD using path_pwd().
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/211-21547336.patch
src/cmd/ksh93/bltins/cd_pwd.c: b_cd():
- The functions path_pwd() and path_relative() in sh/path.c may
return a pointer to e_dot[] (".") as a fallback if they fail to
determine a path. This is a string in read-only memory
(data/msg.c), so must not be freed. A pointer to that string may
end up in sh.pwd (== shp->pwd), so b_cd() needs a check for that.
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
@stephane-chazelas writes:
> Per POSIX[*], cd should skip the $CDPATH processing if the first
> component of the directory given to cd is . or ...
>
> Yet, with ksh93u+m 2021-01-03 at least, while that's OK with ..,
> it's not with . with or without the posix option:
>
> $ CDPATH=/ ./ksh -o posix -c 'cd -P ./etc && pwd'
> /etc
> /etc
>
> It seems to be a regression introduced with ksh93u+ as I can't
> reproduce it with ksh93u or any version prior to that. I can also
> reproduce in u+, v- and the ksh2020 from the Ubuntu 20.04
> package.
src/cmd/ksh93/bltins/cd_pwd.c: b_cd():
- Skip $CDPATH processing not only if the path is absolute, but
also if the initial path component is '.' or '..' (in the latter
case the $CDPATH processing was done but appeared to be a no-op).
src/cmd/ksh93/tests/builtins.sh:
- Add regression test.
[*] https://pubs.opengroup.org/onlinepubs/9699919799.2018edition/utilities/cd.html
Fixes: https://github.com/ksh93/ksh/issues/151
Issuing typeset floating point numerics having a precision of 0
failed as the precision/size was being overwritten with the string
length of the value, e.g. 'typeset -F0 x=5.67' would result in
'typeset -F 4 x=5.6700' as len('5.67') is 4.
src/cmd/ksh93/include/nval.h:
- Created a symbolic name of NV_FLTSIZEZERO to respresent a float
having a precision/size of 0. NV_FLTSIZEZERO needs to be a
negative value.
src/cmd/ksh93/bltins/typeset.c:
- In b_typeset(), added code to set tdata.argnum to NV_FLTSIZEZERO
for E, F, X options.
- In setall(), adjusted code to allow for tp->argnum to be negative.
src/cmd/ksh93/sh/name.c: nv_newattr():
- Adjusted option value only change code to handle NV_FLTSIZEZERO as
well as changed to directly setting np->nvsize instead of using
nv_setsize(np,size) as nv_setsize might contain conflicting and/or
redundant code.
- Added missing conditional check of '!(newatts&NV_INTEGER)' to
constrain the size==0 code block to justified strings as
NV_LJUST, NV_RJUST, or NV_ZFILL are only valid for strings if
NV_INTEGER is not set. This code block was mistakenly setting
the precision/size value to the length of the value of an
assignment for floats whereas it should only be performing
auto assignment length for justified strings.
'typeset -xu' and 'typeset -xl' would export the variable but fail
to change case in the value as the check between old and new
attributes did not provide the necesssary insight for lower or
upper case transcoding due to the lower or upper case attribute
being set within typeset.c prior to calling name.c nv_newattr
function.
Previous rhbz#1188377 patch added a conditional check for size==-1
which in effect caused the nv_newattr export code block return
optimization to never be executed as one cannot set any attributes
using the readonly builtin. By altering the size==-1 check to !trans
the export only optimization can run.
Also, the rhbz#1188377 patch altered new_attr function by setting
the new size to oldsize if run by the readonly builtin. The result
of setting size==oldsize allowed the succeeding if statement to
run more frequently and if size was a non-zero value resulted in
nv_setsize resetting the value to what it already was. Investigation
yielded that size was always 0 coming from the readonly builtin.
src/cmd/ksh93/bltins/typeset.c:
- Remove the setting of tdata.argnum to -1 as it is not needed due to
existing name.c nv_newattr() logic.
src/cmd/ksh93/sh/name.c: nv_newattr():
- Corrected the export only check optimization by using !trans instead
of using size==-1.
- Removed previous condition check to set size=oldsize if coming from
the readonly builtin. nv_newattr already had existing logic to
prevent changing the size via nv_setsize as size is always 0 when
coming from readonly builtin.
Virtual/non-forking subshells that change the present working
directory (PWD) with 'cd' suffer from a serious race condition. The
PWD is changed within the same process. This means it may not be
possible to change back to the original PWD when exiting the
subshell, as some other process may destroy the PWD or modify its
permissions in the meantime. ksh did not handle this error
condition at all, so, after exiting a subshell that invoked 'cd',
it could silently end up running the script's following command(s)
in the wrong directory. Which might be 'rm -rf *'. So, ouch.
The proper and obvious fix is never to allow a virtual subshell to
change the PWD, as it can never be guaranteed you can return to a
previous directory. If the PWD is changed in a child process, there
is no need to restore it in the parent process, and this whole
problem is avoided. So subshells really should always fork on
encountering a 'cd' command.
But forking is slow. It is not uncommon for scripts to 'cd' in a
subshell that is run repeatedly in a loop.
There is also the issue of custom builtins that can be added to ksh
via shared libraries. In the standard shell language, 'cd' is the
only command that changes the PWD, so we could just make that
command fork the subshell it is run from. But there's no telling
what a custom builtin might do.
So this commit implements a compromise that will not affect
performance unless there is the pathological condition of a PWD
that has been rendered inaccessible in some way:
1. When entering a virtual subshell, if the parent shell's PWD
proves inaccessible upon saving it, the subshell will now fork into
a separate process, avoiding the unrestorable PWD problem.
2. If some attack renders the parent shell's PWD unrestorable
*after* ksh enters a virtual subshell, ksh will now error out when
exiting it. There is nothing else left to do then. Continuing would
mean running arbitrary commands in the wrong PWD.
src/cmd/ksh93/sh/subshell.c:
- Put all the code/variables only needed for fchdir() behind '#if
_lib_fchdir'. This makes it clearer what's what.
(I don't know if there is still any system out there without
fchdir(3); I haven't found any. The chdir(3) fallback version may
be removed later as there is no way to make it remotely secure.)
- Fix the attempt to use the O_PATH mode for open(2) as a fallback
for nonexistent O_SEARCH on Linux. Define _GNU_SOURCE on Linux,
or <fcntl.h> (which is included indirectly) won't define O_PATH.
- Fix use of O_SEARCH. The code was simply wrong, repeating an
open(".",O_RDONLY) instead. Since a nonexistent O_SEARCH is now
redefined as either O_PATH or O_RDONLY, we can simply
open(".",O_SEARCH) and be done with it.
- Fix fatal error handling. Introduce fatal error condition for
failure to fchdir(3) back to the parent's PWD; rename 'duped' to
'fatalerror' and use it for error numbers; save and restore errno
on fatal error so the message will report the cause. (We must
call errormsg() near the end of sh_subshell() to avoid crashes.)
- If open(".",O_SEARCH) was not able get a file descriptor to our
PWD on entry, then call sh_subfork() immediately before running
the subshell commands. (Forking earlier causes a crash.)
- When restoring the PWD, if fchdir(3) fails, do *not* fall back to
chdir(3). We already know the PWD is inaccessible, so if chdir(3)
"succeeds" then, it's very likely to be a substitute injected by
an attacker.
src/cmd/ksh93/bltins/cd_pwd.c:
- If we don't have fchdir(3), then sh_subshell() must fall back to
chdir(2) to restore the PWD. That is highly vulnerable, as a
well-timed rename would allow an attacker to usurp the PWD. We
can't do anything about that if some custom builtin changes the
PWD, but we can at least make 'cd' always fork a subshell, which
slows down ksh but removes the need for the parent shell ever to
restore the PWD. (There is certainly no popular system where this
is relevant and there might not be any such current system.)
This commit adds no regression test because a portable regression
test is not really doable. Different kernels, external /bin/pwd
utilities, etc. all have quite different behaviour under the
pathological condition of an inaccessible PWD, so both the
before-fix and the after-fix behaviour differs. See link below.
Resolves: https://github.com/ksh93/ksh/issues/141
Thanks to Stéphane Chazelas for the bug report.
src/cmd/ksh93/bltins/typeset.c: b_typeset():
- For integer bases change argnum check to default values that
are < 2 or > 64 to 10 instead of allowing invalid base values
that ksh cannot process.
src/cmd/ksh93/bltins/typeset.c: setall():
- Remove argnum check for integer base of 1 as base cannot be 1.
- Relocate strlen(name) to inside of conditional check for
np->nvfun as this code does not need to run all.
- Remove no-op oldname code
src/cmd/ksh93/tests/attributes.sh:
- Add typeset -i base bounds checks to default base 10
By definition, subshells are never interactive, so they should
disable behaviour associated with interactive shells even if the
main shell is interactive.
Most visibly, running a background job from a subshell like
( some_command & )
now no longer prints a job ID that you cannot use in the main shell.
This behaviour change matches pdksh/mksh, bash, zsh, dash, et al.
Prior discussion:
https://www.mail-archive.com/austin-group-l@opengroup.org/msg06456.html
(plus the preceding thread)
src/cmd/ksh93/sh/subshell.c: sh_subshell():
- Before running the command(s) in the subshell using sh_exec(),
turn off the SH_INTERACTIVE shell state flag. (No need to add
code to restore it as this function already saves and restores
the entire shell state.)
src/cmd/ksh93/bltins/misc.c: b_bg():
- If there is no job control when using 'bg', 'fg' or 'disown',
always print the "no job control" error message and not only if
the shell is in the interactive state. This is also what
pdksh/mksh, bash and zsh do.
'typeset -xu' and 'typeset -xl' would export the variable but fail
to change case in the value under certain conditions.
Original patch:
642af4d6/f/ksh-20120801-xufix.patch
This applies the patch essentially without change and adds a
regression test based on the reproducer provided in the RH bug.
Unfortunately there is no description of how the patch works and
it's a little obscure to me. As far as I can figure out, the cause
of the problem was that nv_newattr() erroneously processed a
nonexistent size option-argument such as what can be given to
options like typeset -F, e.g. typeset -F3 for 3 digits after the
dot. A nonexistent size argument is represented by the value of -1.
The undocumented alarm builtin executes actions unsafely so that
'read' with an IFS assignment crashed when an alarm was triggered.
This applies an edited version of a Red Hat patch:
642af4d6/f/ksh-20120801-alarmifs.patch
Prior discussion:
https://bugzilla.redhat.com/1176670
src/cmd/ksh93/bltins/alarm.c:
- Add a TODO note based on dgk's 2014 email cited in the RH bug.
- When executing the trap function, save and restore the IFS table.
src/cmd/ksh93/sh/init.c: get_ifs():
- Remove now-unnecessary SHOPT_MULTIBYTE preprocessor directives as
8477d2ce lets the compiler optimise out multibyte code if needed.
- Initialise the 0 position of the IFS table to S_EOF. This
corresponds with the static state tables in data/lexstates.c.
src/cmd/ksh93/tests/builtins.sh:
- Crash test.
According to 'whence --man', 'whence -f' should ignore functions:
-f Do not check for functions.
Right now this is only accomplished partially. As of commit
a329c22d 'whence -f' avoids any output when encountering a
function (in ksh93u+ 'whence -f' has incorrect output). The
return value is still wrong though:
$ foo() { true; }
$ whence -f foo; echo $?
0
This commit fixes the return value and makes 'type -f' error out
when given a function (like in Bash).
src/cmd/ksh93/bltins/whence.c:
- If -f was passed, set 'cp' to NULL since functions should be
ignored (as documented).
- Simplify return value by avoiding bitwise logic.
src/cmd/ksh93/tests/builtins.sh:
- Add regression tests for 'whence -f' and 'type -f'.
Co-authored-by: Martijn Dekker <martijn@inlv.org>
Since at least 1999, whence -v on pdksh (and its successor mksh)
reports the path where an autoloadable function may be found:
$ mkdir ~/fun; FPATH=~/fun
$ echo 'myfn() { echo hi; }' >~/fun/myfn
$ whence -v myfn
myfn is a undefined (autoload from /home/user/fun/myfn) function
Whereas ksh93 only reports, rather uselessly:
myfn is an undefined function
As of this commit, whence -v/-a on ksh 93u+m does the same as
pdksh, but with correct grammar:
myfn is an undefined function (autoload from /home/user/fun/myfn)
This may be a small violation of my own "no new features" policy
for 93u+m, but I couldn't resist. This omission has been annoying
me, and it's just embarrassing to lack a pdksh feature :)
src/cmd/ksh93/include/path.h,
src/cmd/ksh93/data/msg.c:
- Add e_autoloadfrom[] = " (autoload from %s)" message.
src/cmd/ksh93/bltins/whence.c: whence():
- Report the path (if any) when reporting an undefined function.
This needs to be done in two places:
1. When a function has been explicitly marked undefined with
'autoload', we need to do a quick path_search() loop to find
the path. (These undefined functions take precedence over
regular commands, so are reported first.)
2. When a function is not explicitly autoloaded but merely
available in $FPATH, that path search was already done, so all
we need to do is report it. (These are reported last.)
Note that the output remains as on 93u+ if no function definition
file is found on $FPATH. This is also like pdksh/mksh.
src/cmd/ksh93/data/builtins.c:
- Bump 'whence' version date. The inline docs never detailed very
exactly what 'whence -v' reports, so no need for further edits.
src/cmd/ksh93/tests/path.sh:
- Regress-test the new whence behaviour plus actual autoloading,
including the command override behaviour of autoloaded functions.
Hopefully this doesn't introduce new bugs, but it does fix at
least the following:
1. When whence -v/-a found an "undefined" (i.e. autoloadable)
function in $FPATH, it actually loaded the function as a side
effect of reporting on its existence (!). Now it only reports.
2. 'whence' will now canonicalise paths properly. Examples:
$ whence ///usr/lib/../bin//./env
/usr/bin/env
$ (cd /; whence -v dev/../usr/bin//./env)
dev/../usr/bin//./env is /usr/bin/env
3. 'whence' no longer prefixes a spurious double slash when doing
something like 'cd / && whence bin/echo'. On Cygwin, an initial
double slash denotes a network server, so this was not just a
cosmetic problem.
4. 'whence -a' now reports a "tracked alias" (a.k.a. hash table
entry, i.e. cached $PATH search) even if an actual alias by the
same name exists. This needed fixing because in fact the hash
table entry continues to be used when bypassing the alias.
Aliases and "tracked aliases" are not remotely the same thing;
confusing nomenclature is not a reason to report wrong results.
5. When using 'hash' or 'alias -t' on a command that is also a
builtin to force caching a $PATH search for the external
command, 'whence -a' double-reported the path:
$ hash printf; whence -a printf
printf is a shell builtin
printf is /usr/bin/printf
printf is a tracked alias for /usr/bin/printf
This is now fixed so that the second output line is gone.
Plus, if there were multiple versions of the command on $PATH,
the tracked alias was reported at the end, which is the wrong
order. This is also fixed.
src/cmd/ksh93/bltins/whence.c: whence():
- Refactor the do...while loop that handles whence -v/-a for path
searches in such a way that the code actually makes sense and
stops looking like higher esotericism. Just doing this fixed#2,
#4 and #5 above (the latter two before I even noticed them). For
instance, the path_fullname() call to canonicalise paths was
already there; it was just never used.
- Remove broken 'notrack' flaggery for deciding whether to report a
hash table entry a.k.a. "tracked alias"; instead, check the hash
table (shp->track_tree).
src/cmd/ksh93/sh/path.c:
- path_search(): Re #3: When prefixing the PWD, first check if
we're in '/' and if so, don't prefix it; otherwise, adding the
next slash causes an initial double slash. (Since '/' is the only
valid single-character absolute path, all we need to do is check
if the second character pwd[1] is non-null.)
- path_search(): Re #1: Stop autoloading when called by 'whence':
* The 'flag==2' check to avoid autoloading a function was
broken. The flag value is 2 on the first whence() loop
iteration, but 3 on subsequent ones. Change to 'flag >= 2'.
* However, this only fixes it if the function file does not have
the x permission bit, as executable files are handled by
path_absolute() which unconditionally autoloads functions!
So, pass on our flag parameter when callling path_absolute().
- path_absolute(): Re #1: Add flag parameter. Do not autoload
functions if flag >= 2.
src/cmd/ksh93/include/path.h,
src/cmd/ksh93/bltins/typeset.c,
src/cmd/ksh93/sh/main.c,
src/cmd/ksh93/sh/xec.c:
- Re #1: Update path_absolute() calls, adding a 0 flag parameter.
src/cmd/ksh93/include/name.h:
- Remove now-unused pathcomp member from union Value. It was
introduced in 99065353 to allow examining the value of a tracked
alias. This commit uses nv_getval() instead.
src/cmd/ksh93/tests/builtins.sh,
src/cmd/ksh93/tests/path.sh:
- Add and tweak various related tests.
Fixes: https://github.com/ksh93/ksh/issues/84
The following set of commands caused ksh to crash:
$ unalias history; unalias r
Memory fault
When ksh is compiled with -D_std_malloc, the crash always
occurs when the 'r' alias is removed with 'unalias r',
although with vmalloc 'unalias history' must be run first
for the crash to occur. With the native malloc, the crash
message is also different:
$ unalias history; unalias r
free(): invalid pointer
Abort
This crash happens because when an alias is unset, _nv_unset
removes the NV_NOFREE flag which results in an invalid use
of free(3) as nv_isattr no longer detects NV_NOFREE afterward.
The history and r aliases shouldn't be freed from memory by
nv_delete because those aliases are given the NV_NOFREE attribute.
src/cmd/ksh93/bltins/typeset.c:
- Save the state of NV_NOFREE for aliases to fix the crash
caused by 'unalias r'.
src/cmd/ksh93/tests/alias.sh:
- Use unalias on both history and r to check for the crash.
'unalias -a' can't be used to replicate the crash.
Co-authored-by: Martijn Dekker <martijn@inlv.org>
Following a community discussion, it became clear that 'r' is
particularly problematic as a regular builtin, as the name can and
does conflict with at least one legit external command by that
name. There was a consensus against removing it altogether and
letting users set the alias in their login scripts. However,
aliases are easier to bypass, remove or rename than builtins are.
My compromise is to reinstate 'r' as a preset alias on interactive
shells only, along with 'history', as was done in 17f81ebe before
they were converted to builtins in 03224ae3. So this reintroduces
the notion of predefined aliases to ksh 93u+m, but only for
interactive shells that are not initialised in POSIX mode.
src/cmd/ksh93/Makefile,
src/cmd/ksh93/Mamfile,
src/cmd/ksh93/include/shtable.h,
src/cmd/ksh93/data/aliases.c:
- Restore aliases.c containing shtab_aliases[], a table specifying
the preset aliases.
src/cmd/ksh93/include/shtable.h,
src/cmd/ksh93/sh/init.c:
- Rename inittree() to sh_inittree() and make it extern, because we
need to use it in main.c (sh_main()).
src/cmd/ksh93/sh/main.c: sh_main():
- Init preset aliases from shtab_aliases[] only if the shell is
interactive and not in POSIX mode.
src/cmd/ksh93/bltins/typeset.c,
src/cmd/ksh93/tests/alias.sh:
- unall(): When unsetting an alias, pass on the NV_NOFREE attribute
to nv_delete() to avoid an erroneous attempt to free a preset
alias from read-only memory. See: 5d50f825
src/cmd/ksh93/data/builtins.c:
- Remove "history" and "r" entries from shtab_builtins[].
- Revert changes to inline fc/hist docs in sh_opthist[].
src/cmd/ksh93/bltins/hist.c: b_hist():
- Remove handling for 'history' and 'r' as builtins.
src/cmd/ksh93/sh.1:
- Update accordingly.
Resolves: https://github.com/ksh93/ksh/issues/125
The 'exit' and 'return' commands without an argument failed to pass
down the exit status of the last-run command when incorporated in a
block with redirection, &&/|| list, 'case' statement, or 'while',
'until' or 'for' loop.
src/cmd/ksh93/bltins/cflow.c:
- Use $?, which is sh.savexit a.k.a. shp->savexit, as the default
exit status value if there is no argument, instead of
shp->oldexit. This fixes the default exit status behaviour to
match POSIX and other shells.
src/cmd/ksh93/include/defs.h,
src/cmd/ksh93/include/shell.h:
- Remove now-unused sh.oldexit (a.k.a. shp->oldexit) private struct
member. It appeared to fulfill the same function as sh.savexit,
but in a slightly broken way.
- Move the savexit/$? declaration from the _SH_PRIVATE part of the
struct definition to the public API part. Since $? uses this,
it's clearly a publicly exposed value already, and this is
generally the one to use. (If anything, it's exitval that should
have been private.) This declares savexit right next to exitval,
rewriting the comments to clarify the difference between them.
src/cmd/ksh93/sh/fault.c,
src/cmd/ksh93/sh/subshell.c,
src/cmd/ksh93/sh/xec.c:
- Remove assignments to shp->oldexit.
src/cmd/ksh93/tests/basic.sh:
- Add thorough regression tests for the default exit status
behaviour of 'return' and 'exit' in various lexical contexts.
- Verify that 'for' and 'case' without any command, as well as a
lone redirection, still correctly reset the exit status to 0.
Fixes: #117
Using a process of elimination I've identified ${.sh.level}
(SH_LEVELNOD) as the cause of the crash. This node apparently
cannot be copied or moved without destabilising the shell. It
contains the current depth of function calls and it cannot be
changed by assignment, so this is not actually a problem.
Meanwhile, this commit re-fixes it for the other three.
src/cmd/ksh93/sh/subshell.c:
- Simplify sh_assignok() by removing special-casing for L_ARGNOD,
SH_SUBSCRNOD and SH_NAMENOD. 'add' now has 3 modes (0, 1, 2).
- The test for a ${ subshare; } was actually wrong. sp->subshare is
a saved backup value. We must test shp->subshare. (re: a9de50bf)
src/cmd/ksh93/bltins/typeset.c:
- setall(): Update the mode 3 sh_assignok() call.
src/cmd/ksh93/tests/variables.sh:
- Regress-test subshell leaks for all special variables except
${.sh.level}.
This reverts commit b3d37b00b0.
While ksh's own regression test suite passed just fine, when
running the modernish[*] regression tests uite, ksh either froze
hard (needing SIGKILL) or threw a spurious syntax error.
Cause unknown, but I'm certainly reverting until I find out.
This reintroduces a subshell leak for four special variables.
[*] https://github.com/modernish/modernish
The following special variables leaked out of a subshell:
$_, ${.sh.name}, ${.sh.level}, ${.sh.subscript}.
This was due to a faulty optimisation in sh_assignok().
bd3e2a80 fixed that in part, this fixes the rest.
src/cmd/ksh93/sh/subshell.c:
- Simplify sh_assignok() by removing special-casing for these four
special variables. The 'add' param reverts to a simple boolean.
- The test for a ${ subshare; } was actually wrong. sp->subshare is
a saved backup value. We must test shp->subshare. (re: a9de50bf)
src/cmd/ksh93/bltins/typeset.c:
- setall(), unall(): Update sh_assignok() calls.
src/cmd/ksh93/tests/variables.sh:
- Regress-test subshell leaks for all special variables.
Closes: #122
Since ksh 93u+m comes bundled with libast 20111111, there's no need
to support older versions, so this is another cleanup opportunity.
src/cmd/ksh93/include/defs.h:
- Throw an #error if AST_VERSION is undefined or < 20111111.
(Note that _AST_VERSION is the same as AST_VERSION, but the
latter is newer and preferred; see src/lib/libast/features/api)
All other changed files:
- Remove legacy code for versions older than the currently used
versions, which are:
_AST_VERSION 20111111
ERROR_VERSION 20100309
GLOB_VERSION 20060717
OPT_VERSION 20070319
SFIO_VERSION 20090915
VMALLOC_VERSION 20110808
SHOPT_ENV is an undocumented compile-time option implementing an
experimental method for handling environment variables, which is
implemented in env.h and env.c. There is no mention in the docs or
Makefile, and no mention in the mailing list archives. It adds no
new functionality, but at first glance it's a clean-looking
interface.
However, unfortunately, it's broken. Compiling with -DSHOPT_ENV
added to CCFLAGS causes bin/shtests to show these regressions:
functions.sh[341]: export not restored name=value function call -- expected 'base', got ''
functions.sh[1274]: Environment variable is not passed to a function
substring.sh[236]: export not restored name=value function call
variables.sh[782]: SHLVL should be 3 not 2
In addition, 'export' stops working on unset variables.
In the 93v- beta this code is still present, unchanged, though 93v-
made lots of incompatible changes. By the time ksh2020 noticed it,
it was no longer compiling, so it probably wasn't compiling in the
93v- beta either. Discussion: https://github.com/att/ast/issues/504
So the experiment was already abandoned by D. Korn and his team.
Meanwhile it was leaving sh/name.c with two versions of several
enviornment-related functions, and it's not clear which one is
actually compiled without doing detective work tracing header files
(most of the code was made conditional on _ENV_H, which is defined
in env.h, which is included by defs.h if SHOPT_ENV is defined).
This actively hinders understanding of the codebase. And any
changes to these functions would need to be implemented twice.
src/cmd/ksh93/include/env.h,
src/cmd/ksh93/sh/env.c:
- Removed.
src/cmd/ksh93/DESIGN,
src/cmd/ksh93/Makefile,
src/cmd/ksh93/Mamfile:
- Update accordingly.
All other changed files:
- Remove deactivated code behind SHOPT_ENV and _ENV_H.