Turns out there is a way to check what built-in we're running at
any time. It is done for 'let' in arith.c:
sh.bltindata.bnode==SYSLET
For test/[, that would be (see include/builtins.h):
sh.bltindata.bnode==SYSTEST || sh.bltindata.bnode==SYSBRACKET
Symptoms:
$ test \( string1 -a string2 \)
/usr/local/bin/ksh: test: argument expected
$ test \( string1 -o string2 \)
/usr/local/bin/ksh: test: argument expected
The parentheses should be irrelevant and this should be a test for
the non-emptiness of string1 and/or string2.
src/cmd/ksh93/bltins/test.c:
- b_test(): There is a block where the case of 'test' with five or
less arguments, the first and last one being parentheses, is
special-cased. The parentheses are removed as a workaround: argv
is increased to skip the opening parenthesis and argc is
decreased by 2. However, there is no corresponding increase of
tdata.av which is a copy of this function's argv. This renders
the workaround ineffective. The fix is to add that increase.
- e3(): Do not handle '!' as a negator if not followed by an
argument. This allows a right-hand expression that is equal to
'!' (i.e. a test for the non-emptiness of the string '!').
In ksh88, the test/[ built-in supported both the '<' and '>'
lexical sorting comparison operators, same as in [[. However, in
every version of ksh93, '<' does not work though '>' still does!
Still, the code for both is present in test_binop():
src/cmd/ksh93/bltins/test.c
548: case TEST_SGT:
549: return(strcoll(left, right)>0);
550: case TEST_SLT:
551: return(strcoll(left, right)<0);
Analysis: The binary operators are looked up in shtab_testops[] in
data/testops.c using a macro called sh_lookup, which expands to a
sh_locate() call. If we examine that function in sh/string.c, it's
easy to see that on systems using ASCII (i.e. all except IBM
mainframes), it assumes the table is sorted in ASCII order.
src/cmd/ksh93/sh/string.c
64: while((c= *tp->sh_name) && (CC_NATIVE!=CC_ASCII || c <= first))
The problem was that the '<' operator was not correctly sorted in
shtab_testops[]; it was sorted immediately before '>', but after
'='. The ASCII order is: < (60), = (61), > (62). This caused '<' to
never be found in the table.
The test_binop() function is also used by [[, yet '<' always worked
in that. This is because the parser has code that directly checks
for '<' and '>' within [[ (in sh/parse.c, lines 1949-1952).
This commit also adds '=~' to 'test', which took three lines of
code and allowed eliminating error handling in test_binop() as
test/[ and [[ now support the same binary ops. (re: fc2d5a60)
src/cmd/ksh93/*/*.[ch]:
- Rename a couple of very misleadingly named macros in test.h:
. For == and !=, the TEST_PATTERN bit is off for pattern compares
and on for literal string compares! Rename to TEST_STRCMP.
. The TEST_BINOP bit does not denote all binary operators, but
only the logical -a/-o ops in test/[. Rename to TEST_ANDOR.
src/cmd/ksh93/bltins/test.c: test_binop():
- Add support for =~. This is only used by test/[. The method is
implemented in two lines that convert the ERE to a shell pattern
by prefixing it with ~(E), then call test_strmatch with that
temporary string to match the ERE and update ${.sh.match}.
- Since all binary ops from shtab_testops[] are now accounted for,
remove unknown op error handling from this function.
src/cmd/ksh93/data/testops.c:
- shtab_testops[]:
. Correctly sort the '<' (TEST_SLT) entry.
. Remove ']]' (TEST_END). It's not an op and doesn't belong here.
- Update sh_opttest[] documentation with =~, \<, \>.
- Remove now-unused e_unsupported_op[] error message.
src/cmd/ksh93/sh/lex.c: sh_lex():
- Check for ']]' directly instead of relying on the removed
TEST_END entry from shtab_testops[].
src/cmd/ksh93/tests/bracket.sh:
- Add relevant tests.
src/cmd/ksh93/tests/builtins.sh:
- Fix an old test that globally deleted the 'test' builtin. Delete
it within the command substitution subshell only.
- Remove the test for non-support of =~ in test/[.
- Update the test for invalid test/[ op to use test directly.
POSIX requires
test "$a" -a "$b"
to return true if both $a and $b are non-empty, and
test "$a" -o "$b"
to return true if either $a or $b is non-empty.
In ksh, this fails if "$a" is '!' or '(' as this causes ksh to
interpret the -a and -o as unary operators (-a being a file
existence test like -e, and -o being a shell option test).
$ test ! -a ""; echo "$?"
0 (expected: 1/false)
$ set -o trackall; test ! -o trackall; echo "$?"
1 (expected: 0/true)
$ test \( -a \); echo "$?"
ksh: test: argument expected
2 (expected: 0/true)
$ test \( -o \)
ksh: test: argument expected
2 (expected: 0/true)
Unfortunately this problem cannot be fixed without risking breakage
in legacy scripts. For instance, a script may well use
test ! -a filename
to check that a filename is nonexistent. POSIX specifies that this
always return true as it is a test for the non-emptiness of both
strings '!' and 'filename'.
So this commit fixes it for POSIX mode only.
src/cmd/ksh93/bltins/test.c: e3():
- If the posix option is active, specially handle the case of
having at least three arguments with the second being -a or -o,
overriding their handling as unary operators.
src/cmd/ksh93/data/testops.c:
- Update 'test --man --' date and say that unary -a is deprecated.
src/cmd/ksh93/sh.1:
- Document the fix under the -o posix option.
- For test/[, explain that binary -a/-o are deprecated.
src/cmd/ksh93/tests/bracket.sh:
- Add tests based on reproducers in bug report.
Resolves: https://github.com/ksh93/ksh/issues/330
Stéphane Chazelas reported:
> As noted in this austin-group-l discussion[*] (relevant to this
> issue):
>
> $ ksh93u+m -c 'pwd; echo "$?" >&2; echo test; echo "$?" >&2' >&-
> 0
> 1
> /home/chazelas
>
> when stdout is closed, pwd does claim it succeeds (by returning a
> 0 exit status), while echo doesn't (not really relevant to the
> problem here, only to show it doesn't affect all builtins), and
> the output that pwd failed to write earlier ends up being written
> on stderr here instead of stdout upon exit (presumably) because
> of that >&2 redirection.
>
> strace shows ksh93 attempting write(1, "/home/chazelas\n", 15) 6
> times (1, the last one, successful).
>
> It gets even weirder when redirecting to a file:
>
> $ ksh93u+m -c 'pwd; echo "$?" >&2; echo test; echo "$?" > file' >&-
> 0
> $ cat file
> 1
> 1
> ome/chazelas
In my testing, the problem does not occur when closing stdout at
the start of the -c script itself (using redirect >&- or exec >&-);
it only occurs if stdout was closed before initialising the shell.
That made me suspect that the problem had to do with an
inconsistent file descriptor state in the shell. ksh uses internal
sh_open() and sh_close() functions, among others, to maintain that
state.
src/cmd/ksh93/sh/main.c: sh_main():
- If the shell is initialised with stdin, stdout or stderr closed,
then make the shell's file descriptor state tables reflect that
fact by calling sh_close() for the closed file descriptors.
This commit also improves the BUG_PUTIOERR fix from 93e15a30. Error
checking after sfsync() is not sufficient. For instance, on
FreeBSD, the following did not produce a non-zero exit status:
ksh -c 'echo hi' >/dev/full
even though this did:
ksh -c 'echo hi >/dev/full'
Reliable error checking requires not only checking the result of
every SFIO command that writes output, but also synching the buffer
at the end of the operation and checking the result of that.
src/cmd/ksh93/bltins/print.c:
- Make exitval variable global to allow functions called by
b_print() to set a nonzero exit status.
- Check the result of all SFIO output commands that write output.
- b_print(): Always sfsync() at the end, except if the s (history)
flag was given. This allows getting rid of the sfsync() call that
required the workaround introduced in 846ad932.
[*] https://www.mail-archive.com/austin-group-l@opengroup.org/msg08056.html
Resolves: https://github.com/ksh93/ksh/issues/314
Bug 1: POSIX requires numbers used as arguments for all the %d,
%u... in printf to be interpreted as in the C language, so
printf '%d\n' 010
should output 8 when the posix option is on. However, it outputs 10.
This bug was introduced as a side effect of a change introduced in
the 2012-02-07 version of ksh 93u+m, which caused the recognition
of leading-zero numbers as octal in arithmetic expressions to be
disabled outside ((...)) and $((...)). However, POSIX requires
leading-zero octal numbers to be recognised for printf, too.
The change in question introduced a sh.arith flag that is set while
we're processing a POSIX arithmetic expression, i.e., one that
recognises leading-zero octal numbers.
Bug 2: Said flag is not reset in a command substitution used within
an arithmetic expression. A command substitution should be a
completely new context, so the following should both output 10:
$ ksh -c 'integer x; x=010; echo $x'
10 # ok; it's outside ((…)) so octals are not recognised
$ ksh -c 'echo $(( $(integer x; x=010; echo $x) ))'
8 # bad; $(comsub) should create new non-((…)) context
src/cmd/ksh93/bltins/print.c: extend():
- For the u, d, i, o, x, and X conversion modifiers, set the POSIX
arithmetic context flag before calling sh_strnum() to convert the
argument. This fixes bug 1.
src/cmd/ksh93/sh/subshell.c: sh_subshell():
- When invoking a command substitution, save and unset the POSIX
arithmetic context flag. Restore it at the end. This fixes bug 2.
Reported-by: @stephane-chazelas
Resolves: https://github.com/ksh93/ksh/issues/326
Problem:
$ exec ksh
$ echo $SHLVL
2
$ exec ksh
$ echo $SHLVL
3
$ exec ksh
$ echo $SHLVL
4
...etc. SHLVL is supposed to acount the number of shell processes
that you need to exit before you get logged out. Since ksh was
replacing itself with a new shell in the same process using 'exec',
SHLVL should not increase.
src/cmd/ksh93/bltins/misc.c: b_exec():
- When about to replace the shell and we're not in a subshell,
decrease SHLVL to cancel out a subsequent increase by the
replacing shell. Bash and zsh also do this.
BUG 1: Though 'command' is specified/documented as a regular
builtin, preceding assignments survive the invocation (as with
special or declaration builtins) if 'command' has no command
arguments in these cases:
$ foo=wrong1 command; echo $foo
wrong1
$ foo=wrong2 command -p; echo $foo
wrong2
$ foo=wrong3 command -x; echo $foo
wrong3
Analysis: sh_exec(), case TCOM (simple command), contains the
following loop that skips over 'command' prefixes, preparsing any
options and remembering the offset in the 'command' variable:
src/cmd/ksh93/sh/xec.c
1059 while(np==SYSCOMMAND || !np && com0
&& nv_search(com0,shp->fun_tree,0)==SYSCOMMAND)
1060 {
1061 register int n = b_command(0,com,&shp->bltindata);
1062 if(n==0)
1063 break;
1064 command += n;
1065 np = 0;
1066 if(!(com0= *(com+=n)))
1067 break;
1068 np = nv_bfsearch(com0, shp->bltin_tree, &nq, &cp);
1069 }
This skipping is not done if the preliminary b_command() call on
line 1061 (with argc==0) returns zero. This is currently the case
for command -v/-V, so that 'command' is treated as a plain and
regular builtin for those options.
The cause of the bug is that this skipping is even done if
'command' has no arguments. So something like 'foo=bar command' is
treated as simply 'foo=bar', which of course survives.
So the fix is for b_command() to return zero if there are no
arguments. Then b_command() itself needs changing to not error out
on the second/main b_command() call if there are no arguments.
src/cmd/ksh93/bltins/whence.c: b_command():
- When called with argc==0, return a zero offset not just for -v
(X_FLAG) or -V (V_FLAG), but also if there are no arguments left
(!*argv) after parsing options.
- When called with argc>0, do not issue a usage error if there are
no arguments, but instead return status 0 (or, if -v/-V was given,
status 2 which was the status of the previous usage message).
This way, 'command -v $emptyvar' now also works as you'd expect.
BUG 2: 'command -p' sometimes failed after executing certain loops.
src/cmd/ksh93/sh/path.c: defpath_init():
- astconf() returns a pointer to memory that may be overwritten
later, so duplicate the string returned. Backported from ksh2020.
(re: f485fe0f, aa4669ad, <https://github.com/att/ast/issues/959>)
src/cmd/ksh93/tests/builtins.sh:
- Update the test for BUG_CMDSPASGN to check every variant of
'command' (all options and none; invoking/querying all kinds of
command and none) with a preceding assignment. (re: fae8862c)
This also covers bug 2 as 'command -p' was failing on macOS prior
to the fix due to a loop executed earlier in another test.
src/cmd/ksh93/{bltins/typeset,sh/name,sh/nvtree,sh/nvtype}.c:
- Replace more instances of memcmp with strncmp to fix
heap-buffer-overflow errors when running the regression tests
with ASan enabled.
src/cmd/ksh93/edit/vi.c:
- Fix an invalid dereference of the 'p' pointer to fix a crash in
vi mode when entering a comment in the command history. This
bugfix was backported from ksh2020:
https://github.com/att/ast/issues/798
src/cmd/ksh93/tests/pty.sh:
- Add a regression test for the vi mode crash.
src/cmd/ksh93/bltins/typeset.c:
- setall(): Only run sh_assignok() if troot points to the variable
tree. For instance, it's pointless to run it for an alias.
- Remove vestigial SHOPT_BSH code. The ast-open-history repo shows
that earlier SHOPT_BSH code was removed on 2008-06-02 and
2005-05-22. This may have been experimental code for increased
compatibility with the ancient Bourne shell. There was never any
documentation.
src/cmd/ksh93/bltins/typeset.c:
- Removing the nv_search() call altogether was actually not
neccessary, I was just searching the wrong tree: instead of
sh.fun_base, simply search the current sh.fun_tree which has a
view to all the layered parent subshell copes. It is not going to
find it in the current subshell tree but will find it in one of
the parent trees if it exists. The cost of an unnecessary dummy
is negligible, but so is the cost of this search, and doing it is
more correct.
src/cmd/ksh93/bltins/whence.c:
- The previous commit that fixed 'unset -f' in virtual subshells left
one bug. The type builtin (or 'whence -v') could still find the unset
function in virtual subshells:
$ foo() { echo foo; }
$ (unset -f foo; type foo)
foo is an undefined function
To fix this bug, avoid detecting functions in the whence builtin
unless they have the NV_FUNCTION flag.
src/cmd/ksh93/tests/subshell.sh:
- Add a regression test for using 'type' on a function unset inside of
a virtual subshell.
A bug introduced in the previous commit caused 'unset -f' in a
subshell of a subshell to fail to unset a function created in a
parent subshell. Reproducer:
$ ( f2() { echo WRONG; }; ( unset -f f2; f2 ) )
WRONG
src/cmd/ksh93/bltins/typeset.c: unall():
- Do not nv_search() in sh.fun_base before setting the dummy node
that marks the function as unset in this subshell. That search
only reaches the base tree and not any of its subtrees. Setting
the dummy unconditionally is not harmful; the cost is negligible.
src/cmd/ksh93/tests/subshell.sh:
- Add test for the bug.
This commit implements unsetting functions in virtual subshells,
removing the need for the forking workaround. This is done by
either invalidating the function found in the current subshell
function tree by unsetting its NV_FUNCTION attribute bits (which
will cause sh_exec() to skip it) or, if the function exists in a
parent shell, by creating an empty dummy subshell node in the
current function tree without that attribute.
As a beneficial side effect, it seems that bug 228 (unset -f fails
in forked subshells if a function is defined before forking) is now
also fixed.
src/cmd/ksh93/include/defs.h,
src/cmd/ksh93/sh/init.c:
- Add sh.fun_base for a saved pointer to the main shell's function
tree for checking when in a subshell, analogous to sh.var_base.
src/cmd/ksh93/bltins/typeset.c: unall():
- Remove the fork workaround.
- When unsetting a function found in the current function tree
(troot) and that tree is not sh.var_base (which checks if we're
in a virtual subshell in a way that handles shared-state command
substitutions correctly), then do not delete the function but
invalidate it by unsetting its NV_FUNCTION attribute bits.
- When unsetting a function not found in the current function tree,
search for it in sh.fun_base and if found, add an empty dummy
node to mask the parent shell environment's function. The dummy
node will not have NV_FUNCTION set, so sh_exec() will skip it.
src/cmd/ksh93/sh/subshell.c:
- sh_subfuntree(): For 'unset -f' to work correctly with
shared-state command substitutions (subshares), this function
needs a fix similar to the one applied to sh_assignok() for
variables in commit 911d6b06. Walk up on the subshells tree until
we find a non-subshare.
- sh_subtracktree(): Apply the same fix for the hash table.
- Remove table_unset() and incorporate an updated version of its
code in sh_subshell(). As of ec888867, this function was only
used to clean up the subshell function table as the alias table
no longer exists.
- sh_subshell():
* Simplify the loop to free the subshell hash table.
* Add table_unset() code, slightly refactored for readability.
Treat dummy nodes now created by unall() separately to avoid a
memory leak; they must be nv_delete()d without passing the
NV_FUNCTION bits. For non-dummy nodes, turn on the NV_FUNCTION
attribute in case they were invalidated by unall(); this is
needed for _nv_unset() to free the function definition.
src/cmd/ksh93/tests/subshell.sh:
- Update the test for multiple levels of subshell functions to test
a subshare as well. While we're add it, add a very similar test
for multiple levels of subshell variables that was missing.
- Add @JohnoKing's reproducer from #228.
src/cmd/ksh93/tests/leaks.sh:
- Add leak tests for unsetting functions in a virtual subshell.
Test both the simple unset case (unall() creates a dummy node)
and the define/unset case (unall() invalidates existing node).
Resolves: https://github.com/ksh93/ksh/issues/228
There were still problems left after the previous commit. On at
least one system (QNX i386), the following regression test crashed:
src/cmd/ksh93/test/subshell.c
900 got=$( { "$SHELL" -c '(cd /; (cd /)); print -r -- "PWD=$PWD"'; } 2>&1 )
A backtrace done on the core dunp pointed to the free() call here:
src/cmd/ksh93/bltins/cd_pwd.c
90 if(oldpwd && oldpwd!=shp->pwd && oldpwd!=e_dot)
91 free(oldpwd);
Analysis: The interaction between $PWD, sh.pwd aka shp->pwd, and
the path_pwd() function is a mess. path_pwd() usually returns a
freeable value, but not always. sh.pwd is sometimes a pointer to
the value of $PWD, but not always (e.g. when you unset PWD or
assign to it). Instead of debugging the exact cause of the crash, I
think it is better to make this work in a more consistent way.
As of this commit:
1. sh.pwd keeps its own copy of the PWD, independently of the PWD
variable. The old value must always be freed immediately before
assigning a new one. This is simple and consistent, reducing the
chance of bugs at negligible cost.
2. The PWD variable is no longer given the NV_NOFREE attribute
because its value no longer points to sh.pwd. It is now a
variable like any other.
src/cmd/ksh93/sh/path.c: path_pwd():
- Do not give PWDNOD the NV_NOFREE attribute.
- Give sh.pwd its own copy of the PWD by strdup'ing PWDNOD's value.
src/cmd/ksh93/bltins/cd_pwd.c: b_cd():
- Since sh.pwd is now consistently freed before giving it a new
value and at no other time, oldpwd must not be freed any longer
and can become a regular non-static variable.
- If the PWD needs reinitialising, call path_pwd() to do it.
src/cmd/ksh93/sh/subshell.c: sh_subshell():
- Systems with fchdir(2): Always restore the PWD upon exiting a
non-subshare subshell. The check to decide whether or not to
restore it was unsafe: it was not restored if the current PWD
pointer and value was identical to the saved one, but a directory
can be deleted and recreated under the same name.
- Systems without fchdir(2) (if any exist):
. Entry: Fork if the PWD is nonexistent or has no x permission.
. Restore: Only chdir back if the subshell PWD was changed.
That's probably the best we can do. It remains inherently unsafe.
We should probably just require fchdir(2) at some point.
This commit fixes what are hopefully the two final aspects of #153:
1. If the present working directory does not exist (was moved or
deleted) upon entering a virtual subshell, no PWD directory path
is saved. Since restoring the state after exiting a virtual
subshell is contingent on a previous PWD path existing, this
resulted in entire aspects of the virtual subshell, such as the
subshell function tree, not being cleaned up.
2. A separate problem is that 'cd ..' does not update PWD or OLDPWD
when run from a nonexistent directory.
A reproducer exposing both problems is:
$ mkdir test
$ cd test
$ ksh -c '(subfn() { BAD; }; cd ..; echo subPWD==$PWD);
typeset -f subfn; echo mainPWD==$PWD'
subPWD==/usr/local/src/ksh93/ksh/test
subfn() { BAD; };mainPWD==/usr/local/src/ksh93/ksh/test
Expected output:
subPWD==/usr/local/src/ksh93/ksh
mainPWD==/usr/local/src/ksh93/ksh/test
src/cmd/ksh93/bltins/cd_pwd.c:
- If path_pwd() fails to get the PWD (usually it no longer exists),
don't set $OLDPWD to '.' as that is pointless; use $PWD instead.
After cd'ing from a nonexistent directory, 'cd -' *should* fail
and should not be equivalent to 'cd .'.
- Remove a redundant check for (!oldpwd) where it is always set.
- Do not prematurely return without setting PWD or OLDPWD if
pathcanon() fails to canonicalise a nonexistent directory.
Instead, fall back to setting PWD to the result of getcwd(3).
src/cmd/ksh93/sh/subshell.c:
- Minor stylistic adjustment. Some NULL macros sneaked in. This
historic code base does not use them (yet); change to NIL(type*).
- sh_subshell(): Fix logic for determining whether to save/restore
subshell state.
1. When saving, 'if(!comsub || !shp->subshare)' is redundant;
'if(!shp->subshare)' should be enough. If we're not in a
subshare, state should be saved.
2. When restoring, 'if(sp->shpwd)' is just nonsense as there is
no guarantee that the PWD exists upon entering a subshell.
Simply use the same 'if(!shp->subshare)'. Add an extra check
for sp->pwd to avoid a possible segfault. Always restore the
PWD on subshell exit and not only if shp->pwd is set.
- sh_subshell(): Issue fatal errors in libast's "panic" format.
src/cmd/ksh93/tests/builtins.sh:
- Adjust a relevant test to run err_exit() outside of the subshell
so that any error is counted in the main shell.
- Add test for problem 2 described at the top.
src/cmd/ksh93/tests/subshell.sh:
- Add test for problems 1 and 2 based on reproducer above.
Resolves: https://github.com/ksh93/ksh/issues/153
Many of these changes are minor typo fixes. The other changes
(which are mostly compiler warning fixes) are:
NEWS:
- The --globcasedetect shell option works on older Linux kernels
when used with FAT32/VFAT file systems, so remove the note about
it only working with 5.2+ kernels.
src/cmd/ksh93/COMPATIBILITY:
- Update the documentation on function scoping with an addition
from ksh93v- (this does apply to ksh93u+).
src/cmd/ksh93/edit/emacs.c:
- Check for '_AST_ksh_release', not 'AST_ksh_release'.
src/cmd/INIT/mamake.c,
src/cmd/INIT/ratz.c,
src/cmd/INIT/release.c,
src/cmd/builtin/pty.c:
- Add more uses of UNREACHABLE() and noreturn, this time for the
build system and pty.
src/cmd/builtin/pty.c,
src/cmd/builtin/array.c,
src/cmd/ksh93/sh/name.c,
src/cmd/ksh93/sh/nvtype.c,
src/cmd/ksh93/sh/suid_exec.c:
- Fix six -Wunused-variable warnings (the name.c nv_arrayptr()
fixes are also in ksh93v-).
- Remove the unused 'tableval' function to fix a -Wunused-function
warning.
src/cmd/ksh93/sh/lex.c:
- Remove unused 'SHOPT_DOS' code, which isn't enabled anywhere.
https://github.com/att/ast/issues/272#issuecomment-354363112
src/cmd/ksh93/bltins/misc.c,
src/cmd/ksh93/bltins/trap.c,
src/cmd/ksh93/bltins/typeset.c:
- Add dictionary generator function declarations for former
aliases that are now builtins (re: 1fbbeaa1, ef1621c1, 3ba4900e).
- For consistency with the rest of the codebase, use '(void)'
instead of '()' for print_cpu_times.
src/cmd/ksh93/sh/init.c,
src/lib/libast/path/pathshell.c:
- Move the otherwise unused EXE macro to pathshell() and only
search for 'sh.exe' on Windows.
src/cmd/ksh93/sh/xec.c,
src/lib/libast/include/ast.h:
- Add an empty definition for inline when compiling with C89.
This allows the timeval_to_double() function to be inlined.
src/cmd/ksh93/include/shlex.h:
- Remove the unused 'PIPESYM2' macro.
src/cmd/ksh93/tests/pty.sh:
- Add '# err_exit #' to count the regression test added in
commit 113a9392.
src/lib/libast/disc/sfdcdio.c:
- Move diordwr, dioread, diowrite and dioexcept behind
'#ifdef F_DIOINFO' to fix one -Wunused-variable warning and
multiple -Wunused-function warnings (sfdcdio() only uses these
functions when F_DIOINFO is defined).
src/lib/libast/string/fmtdev.c:
- Fix two -Wimplicit-function-declaration warnings on Linux by
including sys/sysmacros.h in fmtdev().
$ /usr/local/bin/ksh -c 'readonly v=1; export v'
/usr/local/bin/ksh: export: v: is read only
Every POSIX shell (even zsh, as of 5.8) allows this. So did ksh,
until the referenced commit.
src/cmd/ksh93/bltins/typeset.c: setall():
- Allow setting attributes on a readonly variable if any of
NV_ASSIGN (== NV_NOFREE), NV_EXPORT or NV_RDONLY are the only
flag bits that are set. This allows readonly, export, typeset -r,
typeset -x, and typeset -rx on variable arguments without an
assignment. Note that NV_ASSIGN is set for the first variable
argument even though it is not an assignment, so we must allow
it. The logic (or lack thereof) of that is yet to be worked out.
src/cmd/ksh93/tests/readonly.sh:
- Tests.
Resolves: https://github.com/ksh93/ksh/issues/258
Ksh currently restricts readonly scalar variables from having their
values directly changed via a value assignment. However, since ksh
allows variable attributes to be altered, the variable's value can
be indirectly altered. For instance, if TMOUT=900 (for a 15 minute
idle timeout) was set to readonly, all that is needed to alter the
value of TMOUT from 900 to 0 is to issue 'typeset -R1 TMOUT',
perhaps followed by a 'typeset -i TMOUT' to turn off the shell's
timeout value.
In addition, there are problems with arrays. The following is
incorrectly allowed:
typeset -a arr=((a b c) 1)
readonly arr
arr[0][1]=d
arr=(alphas=(a b c);name=x)
readonly arr.alphas
arr.alphas[1]=([b]=5)
arr=(alphas=(a b c);name=x)
readonly arr.alphas
arr.alphas[1]=(b)
typeset -C arr=(typeset -r -a alphas=(a b c);name=x)
arr.alphas[1]=()
src/cmd/ksh93/bltins/typeset.c: setall():
- Relocate readonly attribute check higher up the code and widen
its application to issue an error message if the pre-existing
name-pair has the readonly bit flag set.
- To avoid compatibility problems, don't check for readonly if
NV_RDONLY is the only attribute set (ignoring NV_NOFREE). This
allows 'readonly foo; readonly foo' to keep working.
src/cmd/ksh93/sh/array.c: nv_endsubscript():
- Apply a readonly flag check when an array subscript or append
assignment occurs, but allow type variables (typeset -T) as they
utilize '-r' for 'required' sub-variables.
src/cmd/ksh93/tests/readonly.sh:
- New file. Create readonly tests that validate the warning message
and validate that the readonly variable did not change.
src/cmd/ksh93/sh/streval.c:
- Bump MAXLEVEL from 9 to 1024 as a workaround for arithmetic
expansion, avoiding a spurious error about too much recursion
when the readonly.sh tests are run. This change is backported
from ksh 93v-.
TODO: debug a spurious increase in arithmetic recursion level
variable when readonly.sh tests with 'typeset -i' are run.
That is a different bug for a different commit.
Co-authored-by: Martijn Dekker <martijn@inlv.org>
This commit adds an UNREACHABLE() macro that expands to either the
__builtin_unreachable() compiler builtin (for release builds) or
abort(3) (for development builds). This is used to mark code paths
that are never to be reached.
It also adds the 'noreturn' attribute to functions that never
return: path_exec(), sh_done() and sh_syntax(). The UNREACHABLE()
macro is not added after calling these.
The purpose of these is:
* to slightly improve GCC/Clang compiler optimizations;
* to fix a few compiler warnings;
* to add code clarity.
Changes of note:
src/cmd/ksh93/sh/io.c: outexcept():
- Avoid using __builtin_unreachable() here since errormsg can
return despite using ERROR_system(1), as shp->jmplist->mode is
temporarily set to 0. See: https://github.com/att/ast/issues/1336
src/cmd/ksh93/tests/io.sh:
- Add a regression test for the ksh2020 bug referenced above.
src/lib/libast/features/common:
- Detect the existence of either the C11 stdnoreturn.h header or
the GCC noreturn attribute, preferring the former when available.
- Test for the existence of __builtin_unreachable(). Use it for
release builds. On development builds, use abort() instead, which
crahses reliably for debugging when unreachable code is reached.
Co-authored-by: Martijn Dekker <martijn@inlv.org>
This bug was first reported at <https://github.com/att/ast/issues/8>.
The 'cd' command currently takes the value of $OLDPWD from the
wrong scope. In the following example 'cd -' will change the
directory to /bin instead of /tmp:
$ OLDPWD=/bin ksh93 -c 'OLDPWD=/tmp cd -'
/bin
src/cmd/ksh93/bltins/cd_pwd.c:
- Use sh_scoped() to obtain the correct value of $OLDPWD.
- Fix a use-after-free bug. Make the 'oldpwd' variable a static
char that points to freeable memory. Each time cd is used, this
variable is freed if it points to a freeable memory address and
isn't also a pointer to shp->pwd.
src/cmd/ksh93/sh/path.c: path_pwd():
- Simplify and add comments.
- Scope $PWD properly.
src/cmd/ksh93/tests/builtins.sh,
src/cmd/ksh93/tests/leaks.sh:
- Backport the ksh2020 regression tests for 'cd -' when $OLDPWD is
set.
- Add test for $OLDPWD and $PWD after subshare.
- Add test for $PWD after 'cd'.
- Add test for possible memory leak.
- Add testing for 'unset' on OLDPWD and PWD.
src/cmd/ksh93/COMPATIBILITY:
- Add compatibility note about changes to $PWD and $OLDPWD.
Co-authored-by: Martijn Dekker <martijn@inlv.org>
This commit adds '/* FALLTHROUGH */' comments to fix many
GCC warnings when compiling with -Wimplicit-fallthrough.
Additionally, the existing fallthrough comments have been
changed for consistency.
src/cmd/ksh93/bltins/test.c:
- Fix the following compiler warnings from clang:
test.c:554:11: warning: assigning to 'char *' from 'const char []'
discards qualifiers
[-Wincompatible-pointer-types-discards-qualifiers]
e_msg = e_badop;
^ ~~~~~~~
test.c:556:11: warning: assigning to 'char *' from 'const char []'
discards qualifiers
[-Wincompatible-pointer-types-discards-qualifiers]
e_msg = e_unsupported_op;
^ ~~~~~~~~~~~~~~~~
test.c:560:1: warning: control may reach end of non-void function
[-Wreturn-type]
src/cmd/ksh93/tests/builtins.sh:
- Fix regression test by updating error message text.
When test is passed the '=~' operator, it will silently fail with
exit status 1:
$ test foo =~ foo; echo $?
1
This bug is caused by test_binop reaching the 'NOTREACHED' area of
code. The bugfix was adapted from ksh2020:
https://github.com/att/ast/issues/1152
src/cmd/ksh93/bltins/test.c: test_binop():
- Error out with a message suggesting usage of '[[ ... ]]' if '=~'
is passed to the test builtin.
- Special-case TEST_END (']]') as that is not really an operator.
Co-authored-by: Martijn Dekker <martijn@inlv.org>
src/cmd/ksh93/bltins/print.c:
- Rename the unlisted and misleadingly named SHOPT_ECHOE option
(which disables, not enables, 'echo -e') to SHOPT_NOECHOE.
src/cmd/ksh93/SHOPT.sh:
- Add the SHOPT_NOECHOE and SHOPT_TEST_L compile time options to
the list of SHOPT options. Since there is a probe for TEST_L,
set it to probe (empty) by default. NOECHE is off by default.
src/cmd/ksh93/features/options:
- Small bugfix: Allow SHOPT_TEST_L to be manually enabled on
systems that don't support '$(whence -p test) -l /foo'.
- Add a comment describing the SHOPT_MULTIBYTE feature test and
separate it from the SHOPT_DEVFD test.
This bugfix comes from <https://github.com/att/ast/pull/711>.
Eric Scrivner provided the following explanation for the fix:
> Coverity identified an issue with integer truncation in
> `put_enum`. The function was truncating the return values of
> `strcasecmp` and `strcmp` from an `int` to an `unsigned short`
> when assigning them to the local variable `n`. Since either of
> these methods can return a value that is not in the set `{0, 1,
> -1}` the later check if `n == 0` could spuriously evaluate to
> true. For example, in the case where either function returned
> `-65536`.
> The fix is simply to change `n` from an `unsigned short` to an
> `int` to avoid the possibility of truncation. Since the only
> purpose of `n` is the store the return values of these checks,
> this does not have any side effects.
These are minor fixes I've accumulated over time. The following
changes are somewhat notable:
- Added a missing entry for 'typeset -s' to the man page.
- Add strftime(3) to the 'see also' section. This and the date(1)
addition are meant to add onto the documentation for 'printf %T'.
- Removed the man page the entry for ksh reading $PWD/.profile on
login. That feature was removed in commit aa7713c2.
- Added date(1) to the 'see also' section of the man page.
- Note that the 'hash' command can be used instead of 'alias -t' to
workaround one of the caveats listed in the man page.
- Use an 'out of memory' error message rather than 'out of space'
when memory allocation fails.
- Replaced backticks with quotes in some places for consistency.
- Added missing documentation for the %P date format.
- Added missing documentation for the printf %Q and %p formats
(backported from ksh2020: https://github.com/att/ast/pull/1032).
- The comments that show each builtin's options have been updated.
This removes #ifdefs checking for the existence of
SH_PLUGIN_VERSION (version check for dynamically loaded builtins)
and the SFIO identifiers SF_BUFCONST, SF_CLOSING, SF_APPENDWR,
SF_ATEXIT, all of which are defined by the bundled libast.
Until now, when performing any tilde expansion like ~/foo or
~user/foo, ksh added a placeholder built-in command called
'.sh.tilde', ostensibly with the intention to allow users to
override it with a shell function or custom builtin. The multishell
ksh93 repo <https://github.com/multishell/ksh93/> shows this was
added sometime between 2002-06-28 and 2004-02-29. However, it has
never worked and crashed the shell.
This commit replaces that with something that works. Specific tilde
expansions can now be overridden using .set or .get discipline
functions associated with the .sh.tilde variable (see manual,
Discipline Functions).
For example, you can use either of:
.sh.tilde.set()
{
case ${.sh.value} in
'~tmp') .sh.value=${XDG_RUNTIME_DIR:-${TMPDIR:-/tmp}} ;;
'~doc') .sh.value=~/Documents ;;
'~ksh') .sh.value=/usr/local/src/ksh93/ksh ;;
esac
}
.sh.tilde.get()
{
case ${.sh.tilde} in
'~tmp') .sh.value=${XDG_RUNTIME_DIR:-${TMPDIR:-/tmp}} ;;
'~doc') .sh.value=~/Documents ;;
'~ksh') .sh.value=/usr/local/src/ksh93/ksh ;;
esac
}
src/cmd/ksh93/include/variables.h,
src/cmd/ksh93/data/variables.c:
- Add SH_TILDENOD for a new ${.sh.tilde} predefined variable.
It is initially unset.
src/cmd/ksh93/sh/macro.c:
- sh_btilde(): Removed.
- tilde_expand2(): Rewritten. I started out with the tiny version
of this function from the 2002-06-28 version of ksh. It uses the
stack instead of sfio, which is more efficient. A bugfix for
$HOME == '/' was retrofitted so that ~/foo does not become
//foo instead of /foo. The rest is entirely new code.
To implement the override functionality, it now checks if
${.sh.tilde} has any discipline function associated with it.
If it does, it assigns the tilde expression to ${.sh.tilde} using
nv_putval(), triggering the .set discipline, and then reads it
back using nv_getval(), triggering the .get discipline. The
resulting value is used if it is nonempty and does not still
start with a tilde.
src/cmd/ksh93/bltins/typeset.c,
src/cmd/ksh93/tests/builtins.sh:
- Since ksh no longer adds a dummy '.sh.tilde' builtin, remove the
ad-hoc hack that suppressed it from the output of 'builtin'.
src/cmd/ksh93/tests/tilde.sh:
- Add tests verifying everything I can think of, as well as tests
for bugs found and fixed during this rewrite.
src/cmd/ksh93/tests/pty.sh:
- Add test verifying that the .sh.tilde.set() discipline does not
modify the exit status value ($?) when performing tilde expansion
as part of tab completion.
src/cmd/ksh93/sh.1:
- Instead of "tilde substitution", call the basic mechanism "tilde
expansion", which is the term used everywhere else (including the
1995 Bolsky/Korn ksh book).
- Document the new override feature.
Resolves: https://github.com/ksh93/ksh/issues/217
For most numeric types the last provided one wins out. This commit
closes the gap for -F and -i numerics to not be covered up by other
preceding float types. Note: -u for requesting an unsigned float or
integer was considered and decided to be left alone as it stands,
so as to not allow the variable to become an uppercased string if
the requested options ended with a -u. As it stands for a case when
multiple numeric types are requested, a -u option may be applied
after the last numeric type is processed.
Examples:
-EF becomes -F
-Fi becomes -i
-Fu becomes -F
-uF becomes -F
-Fui becomes -i (because isfloat==1, unsigned is not applied)
-Fiu becomes -iu (isfloat is reset and allows unsigned to be set)
src/cmd/ksh93/bltins/typeset.c: b_typeset():
- Reset attribute bit flags for -E and -X when -F is requested by
adding in NV_EXPNOTE to be removed.
- For -i option if a float precedes it, reset isfloat and -E/-F
attribute bit flags.
- Take into account the impact of the shortint flag on floats.
src/cmd/ksh93/tests/attributes.sh:
- Add some validation tests to confirm that, when a -F follows
either -E or -X, -F is used.
- Add some validation tests to confirm that, when -F/E/X precede
a -i, the variable becomes an integer and not a float.
- Add in various tests when -s followed a float.
This commit fixes two interrelated problems.
1. The -v unary test/[/[[ operator is documented to test if a
variable is set. However, it always returns true for variable
names with a numeric attribute, even if the variable has not
been given a value. Reproducer:
$ ksh -o nounset -c 'typeset -i n; [[ -v n ]] && echo $n'
ksh: n: parameter not set
That is clearly wrong; 'echo $n' should never be reached and the
error should not occur, and does not occur on mksh or bash.
2. Fixing the previous problem revealed serious breakage in short
integer type variables that was being masked. After applying
that fix and then executing 'typeset -si var=0':
- The conditional assignment expansions ${var=123} and
${var:=123} assigned 123 to var, even though it was set to 0.
- The expansions ${var+s} and ${var:+n} incorrectly acted as if
the variable was unset and empty, respectively.
- '[[ -v var ]]' and 'test -v var' incorrectly returned false.
The problems were caused by a different storage method for short
ints. Their values were stored directly in the 'union Value'
member of the Namval_t struct, instead of allocated on the stack
and referred to by a pointer, as regular integers and all other
types do. This inherently broke nv_isnull() as this leaves no
way to distinguish between a zero value and no value at all.
(I'm also pretty sure it's undefined behaviour in C to check for
a null pointer at the address where a short int is stored.)
The fix is to store short ints like other variables and refer
to them by pointers. The NV_INT16P combined bit mask already
existed for this, but nv_putval() did not yet support it.
src/cmd/ksh93/bltins/test.c: test_unop():
- Fix problem 1. For -v, only check nv_isnull() and do not check
for the NV_INTEGER attribute (which, by the way, is also used
for float variables by combining it with other bits).
See also 5aba0c72 where we recently fixed nv_isnull() to
work properly for all variable types including short ints.
src/cmd/ksh93/sh/name.c: nv_putval():
- Fix problem 2, part 1. Add support for NV_INT16P. The code is
simply copied and adapted from the code for regular integers, a
few lines further on. The regular NV_SHORT code is kept as this
is still used for some special variables like ${.sh.level}.
src/cmd/ksh93/bltins/typeset.c: b_typeset():
- Fix problem 2, part 2. Use NV_INT16P instead of NV_SHORT.
src/cmd/ksh93/tests/attributes.sh:
- Add set/unset/empty/nonempty tests for all numeric types.
src/cmd/ksh93/tests/bracket.sh,
src/cmd/ksh93/tests/comvar.sh:
- Update a couple of existing tests.
- Add test for [[ -v var ]] and [[ -n ${var+s} ]] on unset
and empty variables with many attributes.
src/cmd/ksh93/COMPATIBILITY:
- Add a note detailing the change to test -v.
src/cmd/ksh93/data/builtins.c,
src/cmd/ksh93/sh.1:
- Correct 'typeset -C' documentation. Variables declared as
compound are *not* initially unset, but initially have the empty
compound value. 'typeset' outputs them as:
typeset -C foo=()
and not:
typeset -C foo
and nv_isnull() is never true for them. This may or may not
technically be a bug. I don't think it's worth changing, but
it should at least be documented correctly.
This commit fixes at least three bugs:
1. When issuing 'typeset -p' for unset variables typeset as short
integer, a value of 0 was incorrectly diplayed.
2. ${x=y} and ${x:=y} were still broken for short integer types
(re: 9f2389ed). ${x+set} and ${x:+nonempty} were also broken.
3. A memory fault could occur if typeset -l followed a -s option
with integers. Additonally, now the last -s/-l wins out as the
option to utilize instead of it always being short.
src/cmd/ksh93/include/name.h:
- Fix the nv_isnull() macro by removing the direct exclusion of
short integers from this set/unset test. This breaks few things
(only ${.sh.subshell} and ${.sh.level}, as far as we can tell)
while potentially correcting many aspects of short integer use
(at least bugs 1 and 2 above), as this macro is widely used.
- union Value: add new pid_t *pidp pointer member for PID values
(see further below).
src/cmd/ksh93/bltins/typeset.c: b_typeset():
- To fix bug 3 above, unset the 'shortint' flag and NV_SHORT
attribute bit upon encountering the -l optiobn.
*** To fix ${.sh.subshell} to work with the new nv_isnull():
src/cmd/ksh93/sh/defs.h:
- Add new 'realsubshell' member to the shgd (aka shp->gd) struct
which will be the integer value for ${.sh.subshell}.
src/cmd/ksh93/sh/init.c,
src/cmd/ksh93/data/variables.c:
- Initialize SH_SUBSHELLNOD as a pointer to shgd->realsubshell
instead of using a short value (.s) directly. Using a pointer
allows nv_isnull() to return a positive for ${.sh.subshell} as
a non-null pointer is what it checks for.
- While we're at it, initialize PPIDNOD ($PPID) and SH_PIDNOD
(${.sh.pid}) using the new pdip union member, which is more
correct as they are values of type pid_t.
src/cmd/ksh93/sh/subshell.c,
src/cmd/ksh93/sh/xec.c:
- Update the ${.sh.subshell} increases/decreases to refer to
shgd->realsubshell (a.k.a. shp->gd->realsubshell).
*** To fix ${.sh.level} after changing nv_isnull():
src/cmd/ksh93/sh/macro.c: varsub():
- Add a specific exception for SH_LEVLNOD to the nv_isnull() test,
so that ${.sh.level} is always considered to be set. Its handling
throughout the code is too complex/special for a simple fix, so
we have to special-case it, at least for now.
*** Regression test additions:
src/cmd/ksh93/tests/attributes.sh:
- Add in missing short integer tests and correct the one that
existed. The -si test now yields 'typeset -x -r -s -i foo'
instead of 'typeset -x -r -s -i foo=0' which brings it in line
with all the others.
- Add in some other -l attribute tests for floats. Note, -lX test
was not added as the size of long double is platform dependent.
src/cmd/ksh93/tests/variables.sh:
- Add tests for ${x=y} and ${x:=y} used on short int variables.
Co-authored-by: Martijn Dekker <martijn@inlv.org>
Corrected the size of attribute(s) being overwritten with 0 when
'readonly' or 'typeset -r' was applied to an existing variable. Since
one cannot set any attributes with the 'readonly' command, its function
call to setall() needs to be adjusted to acquire the current size from
the old size or existing size of the variable. A plain 'typeset -r' is
the same as 'readonly' in that it needs to load the old size as its
current size for use in the subsequent to call to nv_newattr().
src/cmd/ksh93/bltins/typeset.c: setall():
- Both 'readonly' and 'typeset -r' end up calling setall(). setall()
has full visibility into all user supplied values and existing
values that are needed to differentiate whereas name.c newattr()
acquires combined state flags.
- Added a conditional check if the readonly flag was requested by
user then meets the criteria of having present size of 0, cannot
be a numeric nor binary string, and is void of presence of any of
the justified string attributes.
- -L/R/Z justified string attributes if not given a value default
to a size of 0 which means to autosize. A binary string can have
a fixed field size, e.g. -bZ. The present of any of the -L/R/Z
attribules means that current size is valid and should be used
even if it is zero.
src/cmd/ksh93/tests/attributes.sh:
- Added various tests to capture and reiterate that 'readonly' should
be equivalent to 'typeset -r' and applying them should not alter the
previous existing size unless additional attributes are set along
with typeset command.
The referenced commit neglected to add checks for strdup() calls.
That calls malloc() as well, and is used a lot.
This commit switches to another strategy: it adds wrapper functions
for all the allocation macros that check if the allocation
succeeded, so those checks don't need to be done manually.
src/cmd/ksh93/include/defs.h,
src/cmd/ksh93/sh/init.c:
- Add sh_malloc(), sh_realloc(), sh_calloc(), sh_strdup(),
sh_memdup() wrapper functions with success checks. Call nospace()
to error out if allocation fails.
- Update new_of() macro to use sh_malloc().
- Define new sh_newof() macro to replace newof(); it uses
sh_realloc().
All other changed files:
- Replace the relevant calls with the wrappers.
- Remove now-redundant success checks from 18529b88.
- The ERROR_PANIC error message calls are updated to inclusive-or
ERROR_SYSTEM into the exit code argument, so libast's error()
appends the human-readable version of errno in square brackets.
See src/lib/libast/man/error.3
src/cmd/ksh93/edit/history.c:
- Include "defs.h" to get access to the wrappers even if KSHELL is
not defined.
- Since we're here, fix a compile error that occurred with KSHELL
undefined by updating the type definition of hist_fname[] to
match that of history.h.
src/cmd/ksh93/bltins/enum.c:
- To get access to sh_newof(), include "defs.h" instead of
<shell.h> (note that "defs.h" includes <shell.h> itself).
src/cmd/ksh93/Mamfile:
- enum.c: depend on defs.h instead of shell.h.
- enum.o: add an -I. flag in the compiler invocation so that defs.h
can find its subsequent includes.
src/cmd/builtin/pty.c:
- Define one outofmemory() function and call that instead of
repeating the error message call.
- outofmemory() never returns, so remove superfluous exit handling.
Co-authored-by: Martijn Dekker <martijn@inlv.org>
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.
