Summary 0000242: ash: read -t broken
this also implements -n and -s options to read. (they're configured
together because most of their code is in common, and separating them
seemed silly.
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.
