Upstream commit:
Date: Thu, 7 Jul 2011 13:58:48 +0800
[SHELL] Optimize dash -c "command" to avoid a fork
On Sun, Apr 10, 2011 at 07:36:49AM +0000, Jonathan Nieder wrote:
> From: Jilles Tjoelker <jilles@stack.nl>
> Date: Sat, 13 Jun 2009 16:17:45 -0500
>
> This change only affects strings passed to -c, when the -s option is
> not used.
>
> Use the EV_EXIT flag to inform the eval machinery that the string
> being passed is the entirety of input. This way, a fork may be
> omitted in many special cases.
>
> If there are empty lines after the last command, the evalcmd will not
> see the end early enough and forks will not be omitted. The same thing
> seems to happen in bash.
>
> Example:
> sh -c 'ps lT'
> No longer shows a shell process waiting for ps to finish.
>
> [jn: ported from FreeBSD SVN r194128. Bugs are mine.]
>
> Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Instead of detecting EOF using the input layer, I'm going to
use the parser instead. In either case, we always have to read
ahead in order to complete the parsing of the previous node.
Therefore we always know whether there is more to come, except
in the case where we see a newline/semicolon or similar.
For the purposes of sh -c, this should be sufficient.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
function old new delta
evalstring 190 224 +34
ash_main 1014 1022 +8
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/0 up/down: 42/0) Total: 42 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Upstream commit:
Date: Thu, 10 Mar 2011 16:52:13 +0800
[REDIR] Replace GPL noclobberopen code with the FreeBSD version
Replace noclobberopen() from bash with the FreeBSD code for noclobber
opens.
This also reduces code size by eliminating an unnecessary check.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
function old new delta
changepath 192 194 +2
localcmd 366 364 -2
expmeta 521 517 -4
redirect 1210 1135 -75
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/3 up/down: 2/-81) Total: -79 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
We fixed the problem differently than they. Let's not deviate.
Upstream commit:
Date: Thu, 27 May 2010 20:07:29 +1000
[EXPAND] Fix corruption of redirections with byte 0x81
In other ash variants, a partial implementation of ksh-like cmd >file*
adds and removes CTLESC bytes ('\x81') in redirection filenames,
preserving 8-bit transparency. Long ago, dash removed the code to add
the CTLESC bytes, but not the code to remove them, causing corruption of
filenames containing CTLESC. This commit removes the code to remove the
CTLESC bytes.
The CTLESC byte occurs frequently in UTF-8 encoded non-Latin text.
This bug has been reported various times to Ubuntu and Debian (e.g.
Launchpad Ubuntu #422298). This patch is the same as the one submitted
by Alexander Korolkov in Ubuntu #422298.
Signed-off-by: Jilles Tjoelker <jilles@stack.nl>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
function old new delta
changepath 194 192 -2
expandarg 1000 984 -16
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 0/2 up/down: 0/-18) Total: -18 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Upstream commit:
Date: Tue, 25 May 2010 20:55:05 +0800
[VAR] Move unsetvar functionality into setvareq
This patch moves the unsetvar code into setvareq so that we can
no have a pathological case of an unset variable hanging around
unless it has a bit pinning it like VEXPORT.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
function old new delta
setvareq 227 303 +76
expmeta 517 521 +4
localcmd 364 366 +2
unsetcmd 96 76 -20
unsetvar 129 7 -122
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 3/2 up/down: 82/-142) Total: -60 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This change fixes the build in setups where there are
no headers defining WIFSTOPPED and WSTOPSIG (where JOBS has to be
set to 0).
This partially reverts 4700fb5be (ash: make dowait() a bit more
readable. Logic is unchanged, 2015-10-09).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
$ PATH=/extra/path:/usr/sbin:/usr/bin:/sbin:/bin \
> busybox sh -xc 'command -V ls; command -V ls; command -Vp ls; command -vp ls'
+ command -V ls
ls is /bin/ls
+ command -V ls
ls is a tracked alias for /bin/ls
+ command -Vp ls
ls is a tracked alias for (null)
+ command -vp ls
Segmentation fault
describe_command should respect `path' argument. Looking up in the hash table
may gives incorrect index in entry.u.index and finally causes incorrect output
or SIGSEGV.
function old new delta
describe_command 386 313 -73
Signed-off-by: Youfu Zhang <zhangyoufu@gmail.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
When using musl libc glob() a very long string can cause glob() to fail,
which leads to an out of memory error being raised by ash.
This can happen easily if a very long quoted string contains *, even
though no glob expansion should ever be performed on it (since it's
quoted).
Fix this by properly parsing control characters and escaping and only
accept unquoted metacharacters. While we're at it, unify this check for
libc and built-in glob expansion
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
bash has a feature: it restores termios after a successful wait for
a foreground job which had at least one stopped or sigkilled member.
The probable rationale is that SIGSTOP and SIGKILL can preclude task from
properly restoring tty state. Should we do this too?
A reproducer: ^Z an interactive python:
$ python
Python 2.7.12 (...)
>>> ^Z
{ python leaves tty in -icanon -echo state. We do survive that... }
[1]+ Stopped python
{ ...however, next program (python no.2) does not survive it well: }
$ python
Python 2.7.12 (...)
>>> Traceback (most recent call last):
{ above, I typed "qwerty<CR>", but -echo state is still in effect }
File "<stdin>", line 1, in <module>
NameError: name 'qwerty' is not defined
The implementation is modeled on bash code and seems to work.
However, I'm not sure we should do this. For one: what if I'd fg
the stopped python instead? It'll be confused by "restored" tty state.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Mike deleted it:
commit 39456a18a1
Author: Mike Frysinger <vapier@gentoo.org>
Date: Sat Mar 28 12:21:57 2009 +0000
stop lying about [[ test support
probably because it was not properly ifdefed around, and was enabled
even when bash compat is off.
I just tested it - it works:
$ [ *.diff = z.diff ]; echo $?
0
$ [[ *.diff = z.diff ]]; echo $?
1
Of course, not all numerous bash tricks of [[ ]] are implemented...
function old new delta
bltins2 60 72 +12
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Splitting these options makes it self-documenting about what
bash-compatible features we have.
Signed-off-by: Kang-Che Sung <explorer09@gmail.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Splitting these options makes it self-documenting about what
bash-compatible features we have.
Signed-off-by: Kang-Che Sung <explorer09@gmail.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Redundant help texts (one which only repeats the description)
are deleted.
Descriptions and help texts are trimmed.
Some config options are moved, even across menus.
No config option _names_ are changed.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
It's a bit overkill (who would want it off?) but ash already has it
configurable. Let's be symmetric.
Also tweak kbuild logic to use ASH_BUILTIN_ECHO to select echo.o,
not ASH.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Also made it and printf, type and wait builtins optional.
function old new delta
builtin_kill - 323 +323
bltins1 336 348 +12
builtin_type 114 116 +2
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 2/0 up/down: 337/0) Total: 337 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
commit e19923f665 deleted clearredir()
call in shellexec():
ash: [REDIR] Remove redundant CLOEXEC calls
Upstream commit:
Now that we're marking file descriptors as CLOEXEC in savefd, we no longer
need to close them on exec or in setinputfd.
but it missed one place where we don't set CLOEXEC. Fixing this.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This would makes all ash options indented inside "ash" in menuconfig.
It appears that menuconfig has a limit at tracking multiple dependency
lines like this (it looks like a "diamond problem" but I'm not sure if
it is):
---ASH <----------
/ \ ASH_OPTIMIZE_FOR_SIZE
!NOMMU <-*----SH_IS_ASH <----[OR] <--ASH_INTERNAL_GLOB
\ / ASH_RANDOM_SUPPORT
---BASH_IS_ASH <-- [...]
The kconfig-language document [1] states that:
> If a menu entry somehow depends on the previous entry, it can be
> made a submenu of it. First, the previous (parent) symbol must be
> part of the dependency list and then one of these two conditions
> must be true:
> - the child entry must become invisible, if the parent is set to 'n'
[BusyBox ash used to satisfy this, but no longer does]
> - the child entry must only be visible, if the parent is visible
[BusyBox ash configs actually satisfy this, but because of
"diamond" above this might not be easily detected]
So I found out a direct workaround: by making ash options explicitly
depend on !NOMMU, we can tell menuconfig that rule 2 above is satisfied
without any more tracking.
---------------------
/ \
!NOMMU <-*-----ASH <-------- \
\ \ \ ASH_OPTIMIZE_FOR_SIZE
*---SH_IS_ASH <---[OR]-[AND] <--ASH_INTERNAL_GLOB
\ / ASH_RANDOM_SUPPORT
--BASH_IS_ASH <- [...]
So all ash options would now be indented under "ash".
[1] "Documentation/kbuild/kconfig-language.txt" in Linux kernel source
Signed-off-by: Kang-Che Sung <explorer09@gmail.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Mention the behavior if user selects CONFIG_SH_IS_ASH but not
CONFIG_ASH. We will be explicit that invocations like "busybox ash"
will not work for such configuration.
Also clarify help text of CONFIG_BASH_IS_* that bash compatibility in
ash is not complete. (It shouldn't be anyway - ash can't support every
bash quirk out there.)
Signed-off-by: Kang-Che Sung <explorer09@gmail.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
The commit 'ash,hush: set exit code 127 in "sh /does/not/exist" case'
only partly implemented the dash commit '[ERROR] Allow the originator
of EXERROR to set the exit status'. This resulted in incorrect error
codes for a syntax error:
$ )
$ echo $?
0
or a redirection error for a special builtin:
$ rm -f xxx
$ eval cat <xxx
$ echo $?
0
Signed-off-by: Ron Yorston <rmy@pobox.com>
Reported-by: Martijn Dekker <martijn@inlv.org>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
The same can be done for msh, but we are probably better off just deleting it
in a next versio or two.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
PIPE_SEQ is used most often, having it zero makes code smaller:
function old new delta
done_word 719 707 -12
parse_stream 2546 2531 -15
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
I thought gcc can detect this itself. It doesn't.
function old new delta
run_list 1030 1021 -9
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Was playing with "sleep 3 | exit 3 & wait %1" and noticed that often
SIGCHLD arrives even before I get to signal masking. Can avoid it in this
case.
function old new delta
wait_for_child_or_signal 228 265 +37
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Also add tests. wait5.tests so far fails (but works for ash and dash).
function old new delta
builtin_wait 305 283 -22
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
It would be nice to provide bash-like "remember las exitcode"
thingy, but it's a bit complex. For now, match ash and dash.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
