If we exec /proc/self/exe and only fall back to /bin/busybox if /proc isn't
there, then we have a reasonable chance of having the standalone shell work
even if busybox isn't installed in /bin on the system in question.
Still won't work in a chroot environment, but it's an improvement.
Hi!
I've created a patch to busybox' build system to allow building it in
separate tree in a manner similar to kbuild from kernel version 2.6.
That is, one runs command like
'make O=/build/some/where/for/specific/target/and/options'
and everything is built in this exact directory, provided that it exists.
I understand that applyingc such invasive changes during 'release
candidates' stage of development is at best unwise. So, i'm currently
asking for comments about this patch, starting from whether such thing
is needed at all to whether it coded properly.
'make check' should work now, and one make creates Makefile in build
directory, so one can run 'make' in build directory after that.
One possible caveat is that if we build in some directory other than
source one, the source directory should be 'distclean'ed first.
egor
CONFIG_FEATURE_COMMAND_EDITING was defined *and*
CONFIG_FEATURE_COMMAND_TAB_COMPLETION was undefined.
Vladimir N. Oleynik writes:
Its declare always, also if CONFIG_FEATURE_COMMAND_TAB_COMPLETION
undefined.
Patch to CVS version attached.
--w
vodz
This patch makes msh handle variable expansion within backticks more
correctly.
Current behaviour (wrong):
--------------------------
BusyBox v1.00-rc3 (2004.08.26-11:51+0000) Built-in shell (msh)
Enter 'help' for a list of built-in commands.
$ A='`echo hello`'
$ echo $A
`echo hello`
$ echo `echo $A`
hello
$
New behaviour (correct):
------------------------
BusyBox v1.00-rc3 (2004.08.26-11:51+0000) Built-in shell (msh)
Enter 'help' for a list of built-in commands.
$ A='`echo hello`'
$ echo $A
`echo hello`
$ echo `echo $A`
`echo hello`
$
The current behaviour (wrong according to standards) was actually my
fault. msh handles backticks by executing a subshell (which makes it
work on MMU-less systems). Executing a subshell makes it hard to only
expand variables once in the parent. Therefore I export all variables
that will be expanded within the backticks and let the subshell handle
the expansion instead.
The bug was found while searching for security leaks in CGI-scripts.
Current behaviour of msh makes it easy to expand backticks by mistake
in $QUERY_STRING. I recommend appling the patch before release of bb
1.00.
/Jonas
On Wed Aug 18, 2004 at 06:52:57PM +0800, Matt Johnston wrote:
> I've come across some strange-seeming behaviour when running programs
> under Busybox (1.0.0-rc3) ash. If the child process sets stdin to be
> non-blocking and then exits, the parent ash will also exit. A quick strace
> shows that a subsequent read() from stdin returns EAGAIN (as would be
> expected):
Thanks!
Patch attached.
--w
vodz
This bug is in busybox 1.0.0-rc2. When using lash exec
builtin with redirection, the opened file fd keep increasing.
For example, please try the following command with lash.
ls -al /proc/<lash pid>/fd
exec /bin/sh 2>/dev/null
ls -al /proc/<lash pid>/fd
The last 'ls' command output will look like this. The fd
number 4 shouldn't exist.
lrwx------ 1 501 100 64 Aug 13 13:56 4 -> /dev/pts/5
l-wx------ 1 501 100 64 Aug 13 13:56 2 -> /dev/null
lrwx------ 1 501 100 64 Aug 13 13:56 1 -> /dev/pts/5
lrwx------ 1 501 100 64 Aug 13 13:56 0 -> /dev/pts/5
dr-xr-xr-x 3 501 100 0 Aug 13 13:56 ..
dr-x------ 2 501 100 0 Aug 13 13:56 .
This one-line patch fix this problem by setting CLOEXEC flag for
squirrel fd. Please apply.
Joe.C
A question was posted a month ago by Mark Alamo to see if others had
problems with sourcing subscripts within msh. We asked his firm to fix the
msh.c bug he described because we didn't have enough time to do it
ourselves.
When msh.c is executing a compound statement and there is a . command to
source another script file, msh.c will not execute the subscript until it's
completed executing the rest of the compound statement.
His example was this:
Echo "Start" ; . ./subA; echo "mid" ; . ./subB ; echo "end"
subA and subB execute AFTER end is printed in reverse order. The same is
true if the sourced files are inside an if else fi, case esac, or any
compound statement.
Attached is a patch to msh.c. It fixes the problem. Cd to the root of your
busybox tree and execute "patch -p1 < msh.c.patch"
Unfortunately, I won't have more time to work on this so I hope that there
aren't any problems!
Michael Leibow
Senior Software Engineer
Belkin Corporation
With job control enabled, ash fails to tcsetpgrp back to initialpgrp
upon exit. exitshell() should call setjobctl(0) to do this.
Context: I am using a lightweight menu system (replimenu[.sf.net]) on my
console, which invokes "/bin/sh -i -c /bin/login", where /bin/sh and
/bin/login are busybox applets. /bin/sh is ash, with
CONFIG_ASH_JOB_CONTROL=y as the sole suboption. The shell of the user
concerned (nobody) is also /bin/sh (ash). When the user /bin/sh exits
(and thereby login and its parent sh), replimenu receives EIO when it
tries to read from the terminal.
The updated patch adds a config option to explicitely enable 64 bit
arithmetic.
Also it removes the arith prototype from libbb.h as it is not used
outside of ash.
Bastian
this patch has been slightly modified by Erik for cleanliness.
This is a bulk spelling fix patch against busybox-1.00-pre10.
If anyone gets a corrupted copy (and cares), let me know and
I will make alternate arrangements.
Erik - please apply.
Authors - please check that I didn't corrupt any meaning.
Package importers - see if any of these changes should be
passed to the upstream authors.
I glossed over lots of sloppy capitalizations, missing apostrophes,
mixed American/British spellings, and German-style compound words.
What is "pretect redefined for test" in cmdedit.c?
Good luck on the 1.00 release!
- Larry
He,
there is a bug in HUSH's handling of "if" / "elif" commands:
$ if true
> then
> echo 1
> elif
> true
> then
> echo 2
> elif
> true
> then
> echo 3
> else
> echo 4
> fi
1
2
3
$
The same bug exists in all versions of HUSH from BB v0.60.x up to and
including v1.00-pre9. The attached patch fixes this:
$ if true
> then
> echo 1
> elif
> true
> then
> echo 2
> elif
> true
> then
> echo 3
> else
> echo 4
> fi
1
$
Best regards,
Wolfgang Denk
Just upgraded from 0.6 to 1.00-pre8
Dot command handling handled args correctly (same as bash) in 0.60,
but failed in 1.00:
I fixed this by reverting the dotcmd function back to previous 0.60
instantiation,
please consider using the older version.
Thanks
Peter
It looks like latest uClibc defines ARCH_HAS_MMU, but a few busybox files
test UCLIBC_HAS_MMU, resulting in vfork() getting called instead of
fork(), etc.
Patch below. Only tested for lash.
Cheers,
-Jamie
have checked in. Vladimir writes:
Your patch have many problem.
1. You always added + time(). This cannot reset RANDOM=value for debuging
with
replay sequential.
2. Hmm. I examine bash 2.04 source. This pseudorandom generator use low bits
of
counter value. You use high bits. This make bad pseudorandom values after
have
0-value. For example, if + time() do remove, your generator always return 0
after
first generate 0.
3. Memory leak per call. Use ash-unlike unecessary bb_strdup function.
4. Unsupport show last $RANDOM value for "set" and "export" command.
5. Bloat code. Busybox-unlike patch - added unstandart feature as default
hardcode.
Last patch attached.
Erik, why you apply Paul patch with have 5-th point problem? :(
Last patch have ash change xwrite() to fresh libbb/bb_full_write interfase
(haved loop after EINTR).
--w
vodz
Here's a follow-up replacement to the patch I sent earlier, this adjusts some
of the semantics of the dynamic variable setting. Namely, dynamic vars can hook
a set handler (which RANDOM uses to adjust the seed). They'll only lose their
dynamic status if they're unset.
I've used the same approach that bash does to come up with the random number,
mostly just for consistency.
For example:
$ echo $RANDOM
13759
$ echo $RANDOM
20057
$ echo $RANDOM
1502
$ export RANDOM=42
$ echo $RANDOM
24179
$ echo $RANDOM
2046
$ unset RANDOM
$ echo $RANDOM
$ export RANDOM=42
$ echo $RANDOM
42
$
- declare applet_using as static from applets.c
- small correction to cmdedit,
previous version cleared history after Ctrl-C
- small spelling correction (by Friedrich Lobenstock)
