1
0
Fork 0
mirror of git://git.code.sf.net/p/cdesktopenv/code synced 2025-02-13 11:42:21 +00:00
cde/NEWS
Martijn Dekker 1026006db3 Fix BUG_KBGPID: $! was not updated under certain conditions
The $! special parameter was not set if a background job
(somecommand &) or co-process (somecommand |&) was launched as the
only command within a braces block with an attached redirection,
for example:
	{
		somecommand &
	} >&2
With the bug, $! was unchanged; now it contains the PID of
somecommand.

Ref.: https://github.com/att/ast/issues/1357

src/cmd/ksh93/sh/parse.c: item():
- When processing redirections following a compound command, always
  create a parent node with the TSETIO (I/O redirection) token.
     Before this commit, if the last command was of type TFORK (and
  the last command only tested as TFORK if the bg job or coprocess
  was the only command in a braces block, because the ksh parser
  optimises away the braces in that case), then the parent node was
  created with the TFORK token instead.
     I have no idea what David Korn's intention was with that, but
  this is clearly very wrong. Creating another TFORK node when
  parsing the redirection caused sh_exec() in sh/xec.c to execute
  the redirection in an extra forked, non-background subshell.
  Since redirections are executed before anything else, this
  subshell is what then launched the background job between the
  braces, so $! (a.k.a. shp->bckpid) was updated in that subshell
  only, and never in the main shell. The extra subshell also
  prevented the background job from being noticed by job control
  on interactive shells.
     So, the fix is simply to remove the broken test for TFORK.

src/cmd/ksh93/tests/variables.sh:
- Add regression tests for a bg job and a co-process as the only
  command within a braces block with attached redirection.

(cherry picked from commit ffe5df30e69f7b596941a98498014d8e838861f2)
2020-06-12 01:45:15 +02:00

133 lines
5.3 KiB
Text

This documents significant changes in the 93u+m branch of AT&T ksh93.
For full details, see the git log at:
https://github.com/modernish/ksh
Any uppercase BUG_* names are modernish shell bug IDs.
2020-06-04:
- Fix BUG_KBGPID: the $! special parameter was not set if a background job
(somecommand &) or co-process (somecommand |&) was launched as the only
command within a braces block with an attached redirection, for example:
{
somecommand &
} >&2
With the bug, $! was unchanged; now it contains the PID of somecommand.
2020-05-31:
- Fix a bug in autoloading functions. Directories in the path search list
which should be skipped (e.g. because they don't exist) did not interact
correctly with autoloaded functions, so that a function to autoload was
not always found correctly.
Details: https://github.com/att/ast/issues/1454
2020-05-30:
- Fix POSIX compliance of 'test'/'[' exit status on error. The command now
returns status 2 instead of 1 when given an invalid number or arithmetic
expression, e.g.:
[ 123 -eq 123x ]; echo $?
now outputs 2 instead of 1.
2020-05-29:
- Fix BUG_FNSUBSH: functions can now be correctly redefined and unset in
subshell environments (such as ( ... ), $(command substitutions), etc).
Before this fix, this was silently ignored, causing the function by the
same name from the parent shell environment to be executed instead.
fn() { echo mainsh; }
(fn() { echo subsh; }; fn); fn
This now correctly outputs "subsh mainsh" instead of "mainsh mainsh".
ls() { echo "ls executed"; }
(unset -f ls; ls); ls
This now correctly lists your directory and then prints "ls executed",
instead of printing "ls executed" twice.
- Fix a similar bug with aliases. These can now be correctly unset
in subshell environments.
2020-05-21:
- Fix truncating of files with the combined redirections '<>;file' and
'<#pattern'. The bug was caused by out-of-sync streams.
Details and discussion: https://github.com/att/ast/issues/61
- Patched code injection vulnerability CVE-2019-14868. As a result, you can
no longer use expressions in imported numeric environment variables; only
integer literals are allowed.
2020-05-20:
- Fix BUG_ISSETLOOP. Expansions like ${var+set} remained static when used
within a 'for', 'while' or 'until' loop; the expansions din't change along
with the state of the variable, so they could not be used to check whether a
variable is set within a loop if the state of that variable changed in the
course of the loop.
- Fix BUG_IFSISSET. ${IFS+s} always yielded 's', and [[ -v IFS ]] always
yielded true, even if IFS is unset. This applied to IFS only.
2020-05-19:
- Fix 'command -p'. The -p option causes the operating system's standard
utilities path (as output by 'getconf PATH') to be searched instead of $PATH.
Before this fix, this was broken on non-interactive shells as the internal
variable holding the default PATH value was not correctly initialised.
2020-05-16:
- Fix 'test -t 1', '[ -t 1 ]', '[[ -t 1 ]]' in command substitutions.
Standard output (file descriptor 1) tested as being on a terminal within a
command substitution, which makes no sense as the command substitution is
supposed to be catching standard output.
v=$(echo begincomsub
[ -t 1 ] && echo oops
echo endcomsub)
echo "$v"
This now does not output "oops".
2020-05-14:
- Fix syncing history when print -s -f is used. For example, the
following now correctly adds a 'cd' command to the history:
print -s -f 'cd -- %q\n' "$PWD"
Ref.: https://github.com/att/ast/issues/425
https://github.com/att/ast/pull/442
- Fix BUG_PUTIOERR: Output builtins now correctly detect and report
input/output errors. This allows scripts to check for a nonzero exit
status on the 'print', 'printf' and 'echo' builtins and prevent possible
infinite loops if SIGPIPE is ignored.
- Add a convenient bin/run_ksh_tests script to the source tree that
sets up the necessary environment and runs the ksh regression tests.
2020-05-13:
- Fix BUG_CASELIT: an undocumented 'case' pattern matching misbehaviour that
goes back to the original Bourne shell, but wasn't discovered until 2018.
If a pattern doesn't match as a pattern, it was tried again as a literal
string. This broke common validation use cases, e.g.:
n='[0-9]'
case $n in
( [0-9] ) echo "$n is a number" ;;
esac
would output "[0-9] is a number" as the literal string fallback matches the
pattern. As this misbehaviour was never documented anywhere (not for Bourne,
ksh88, or ksh93), and it was never replicated in other shells (not even in
ksh88 clones pdksh and mksh), it is unlikely any scripts rely on it.
Of course, a literal string fallback, should it be needed, is trivial to
implement correctly without this breakage:
case $n in
( [0-9] | "[0-9]") echo "$n is a number or the number pattern" ;;
esac
Ref.: https://github.com/att/ast/issues/476
- Fix BUG_REDIRIO: ksh used to redirect standard output by default when no
file descriptor was specified with the rarely used '<>' reading/writing
redirection operator. It now redirects standard input by default, as POSIX
specifies and as all other POSIX shells do. To redirect standard output
for reading and writing, you now need '1<>'.
Ref.: https://github.com/att/ast/issues/75
http://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#tag_18_07_07