Dixi quod…
>Commit ID: 10058E5A1067AFA1BBA
>Log message:
>fix reentrancy of 'typeset -f' output in the face of aliases; also,
>move alias handling for COMSUBs and friends to parse time by request
>of Martijn Dekker (and for consistency with function definitions)
Oh well. For the sake of consistency. But fixing this DID uncover
a re-entrancy bug in 'typeset -f' ouput (which IS also used in some
other places internally):
The old comsub-5 tested this:
print '#!/bin/mksh\nfor x in "$@"; do print -r -- "$x"; done' >pfn
chmod +x pfn
alias echo='echo a'
foo() {
./pfn "$(echo foo)"
}
typeset -f foo
expected-stdout:
foo() {
./pfn "$(echo foo )"
}
But what if we try to re-enter it?
print '#!/bin/mksh\nfor x in "$@"; do print -r -- "$x"; done' >pfn
chmod +x pfn
alias echo='echo a'
foo() {
echo moo
./pfn "$(echo foo)"
}
typeset -f foo >x
cat x
foo
. ./x
typeset -f foo
foo
When deferring alias interpretation until the end, we do get:
foo() {
echo a moo
./pfn "$(echo foo )"
}
a moo
a foo
foo() {
echo a a moo
./pfn "$(echo foo )"
}
a a moo
a foo
With this, we also get:
alias echo=print
x() { echo a; (echo b); x=$(echo c); }
typeset -f x
⇒
x() {
print a
( print b )
x=$(echo c )
}
This is problematic (in the first two) and inconsistent (in the last) case.
With the code I committed, we get:
foo() {
\echo a moo
./pfn "$(\echo a foo )"
}
a moo
a foo
foo() {
\echo a moo
./pfn "$(\echo a foo )"
}
a moo
a foo
To make this work but not get “\./pfn” stupidly, I had to limit the
allowed characters in “alias”, but ksh93 does so too, as does POSIX.
So, in the end… yes, thank you.
Welterusten,
//mirabilos (who doesn’t get enough Cider for this)
PS: sleepless unite! ☺
--
<igli> exceptions: a truly awful implementation of quite a nice idea.
<igli> just about the worst way you could do something like that, afaic.
<igli> it's like anti-design. <mirabilos> that too… may I quote you on that?
<igli> sure, tho i doubt anyone will listen ;)
