Upstreams commit:
Date: Mon, 8 Oct 2007 21:32:25 +0800
[PARSER] Report substition errors at expansion time
On Wed, Apr 11, 2007 at 01:24:21PM -0700, Micah Cowan wrote:
> This operation fails on Ubuntu:
>
> $ /bin/sh -c 'if false; then d="${foo/bar}"; fi'
> /bin/sh: Syntax error: Bad substitution
>
> When used with other POSIX shells it succeeds. While semantically the
> variable reference ${foo/bar} is not valid, this is not a syntax error
> according to POSIX, and since the variable assignment expression is
> never invoked (because it's within an "if false") it should not be seen
> as an error.
>
> I ran into this because after restarting my system I could no longer log
> in. It turns out that the problem was (a) I had edited .gnomerc to
> source my .bashrc file so that my environment would be set properly, and
> (b) I had added some new code to my .bashrc WITHIN A CHECK FOR BASH!
> that used bash's ${var/match/sub} feature. Even though this code was
> within a "case $BASH_VERSION; in *[0-9]*) ... esac (so dash would never
> execute it since that variable is not set), it still caused dash to
> throw up.
>
> FYI, some relevant details from POSIX:
>
> Section 2.3, Token Recognition:
>
> 5. If the current character is an unquoted '$' or '`', the shell shall
> identify the start of any candidates for parameter expansion ( Parameter
> Expansion), command substitution ( Command Substitution), or arithmetic
> expansion ( Arithmetic Expansion) from their introductory unquoted
> character sequences: '$' or "${", "$(" or '`', and "$((", respectively.
> The shell shall read sufficient input to determine the end of the unit
> to be expanded (as explained in the cited sections).
>
> Section 2.6.2, Parameter Expansion:
>
> The format for parameter expansion is as follows:
>
> ${expression}
>
> where expression consists of all characters until the matching '}'. Any
> '}' escaped by a backslash or within a quoted string, and characters in
> embedded arithmetic expansions, command substitutions, and variable
> expansions, shall not be examined in determining the matching '}'.
> [...]
>
> The parameter name or symbol can be enclosed in braces, which are
> optional except for positional parameters with more than one digit or
> when parameter is followed by a character that could be interpreted as
> part of the name. The matching closing brace shall be determined by
> counting brace levels, skipping over enclosed quoted strings, and
> command substitutions.
> ---
> In addition to bash I've checked Solaris /bin/sh and ksh and they don't
> report an error.
>
> -----
> Micah Cowan:
>
> The applicable portion of POSIX is in XCU 2.10.1:
>
> "The WORD tokens shall have the word expansion rules applied to them
> immediately before the associated command is executed, not at the time
> the command is parsed."
>
> This seems fairly clear to me.
This patch moves the error detection to expansion time.
Test case:
if false; then
echo ${a!7}
fi
echo OK
Old result:
dash: Syntax error: Bad substitution
New result:
OK
function old new delta
evalvar 574 585 +11
readtoken1 2763 2750 -13
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Upstream commit:
Date: Thu, 27 May 2010 14:21:17 +0800
[REDIR] Move null redirect checks into caller
The null redirect checks were added as an optimisation to avoid
unnecessary memory allocations. However, we could avoid this
completely by simply making the caller avoid making a redirection
unless it is not null.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
function old new delta
evaltree 784 809 +25
evalcommand 1251 1261 +10
hashvar 59 62 +3
dotcmd 321 319 -2
clearredir 37 30 -7
popredir 183 162 -21
redirect 1264 1233 -31
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 4/4 up/down: 63/-61) Total: -23 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Upstream patch:
Date: Thu, 27 Dec 2007 13:57:07 +1100
[PARSER] Do not show prompts in expandstr
Once I fixed the previous problem it became apparent that we never dealt
with prompts with new-lines in them correctly. The problem is that we
showed a secondary prompt for each of them.
This patch disables prompt generation in expandstr.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
function old new delta
expandstr 102 127 +25
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Upstream commit:
Date: Sun, 11 Nov 2007 15:00:06 +0800
[EXPAND] Removed herefd hack
The herefd hack goes back more than a decade. it limits the amount of
memory we have to allocate when expanding here-documents by writing the
result out from time to time. However, it's no longer safe because the
stack is used to place intermediate results too and there we certainly
don't want to write them out should we be short on memory.
In any case, with today's computers we can afford to keep the entire
result in memory and write them out at the end.
function old new delta
redirect 1268 1264 -4
ash_main 1485 1478 -7
subevalvar 1157 1132 -25
growstackstr 54 24 -30
argstr 1192 1154 -38
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 0/5 up/down: 0/-104) Total: -104 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Upstream commit:
We need to flush at the very end in case we've generated any errors
before that. The flushall call cannot perform a longjmp so it's
safe there.
Date: Sat, 22 Sep 2007 20:50:21 +0800
[SHELL] Move flushall to the point just before _exit
We need to flush at the very end in case we've generated any errors
before that. The flushall call cannot perform a longjmp so it's
safe there.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Upstream patch:
Date: Tue, 15 Mar 2011 15:44:47 +0800
[EVAL] Let funcnode refer to a function definition, not its first command
It is not unrelated: I changed the meaning of struct funcnode's field n
to refer to the function definition, rather than the list of the
function's commands, because I needed to refer to the function
definition node from evalfun, which only gets passed a funcnode. But it
is something that could be applied independently (without being useful
by itself), so I've attached it as a separate patch for easier review.
Signed-off-by: Harald van Dijk <harald@gigawatt.nl>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Upstream commit:
Date: Sun, 6 May 2007 12:01:37 +1000
[REDIR] Remove EMFILE special case
No caller of copyfd need to ignore EMFILE so we can remove the special
case and just let it call sh_error on any error.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Upstream commit:
Date: Tue, 6 Jul 2010 17:50:37 +0800
[PATCH 161/277] [EVAL] Check exit for eval NSUBSHELL
Example:
$ dash -c 'set -e; (false); echo here'
here
With this commit, dash exits 1 before echo.
The bug was reported by Stefan Fritsch through
http://bugs.debian.org/514863
Signed-off-by: Gerrit Pape <pape@smarden.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This was fixed differently in our tree:
Date: Fri Sep 16 19:04:02 2016 +0000
ash: exit after subshell error when errexit option is set
When "set -e" option is on, shell must exit when any command fails,
including compound commands of the form (compound-list) executed in a
subshell. Bash and dash shells have this behaviour.
Also add a corresponding testcase.
Signed-off-by: Rostislav Skudnov <rostislav@tuxera.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Upstream commit:
Date: Wed, 8 Sep 2010 16:21:52 +0800
[JOBS] Debug compile fix
No point in tracing a no longer undeclared "ps->cmd", fixes:
jobs.c: In function \u2018commandtext\u2019:
jobs.c:1192: error: \u2018ps\u2019 undeclared (first use in this function)
jobs.c:1192: error: (Each undeclared identifier is reported only once
jobs.c:1192: error: for each function it appears in.)
Signed-off-by: maximilian attems <max@stro.at>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Upstream commit:
Date: Sun, 28 Nov 2010 20:47:07 +0800
[BUILTIN] Stop documenting EXSHELLPROC
At some point between ash 0.3.5-11.0.1 and ash 0.3.8-37, Debian
ash stopped using the EXSHELLPROC exception to handle shell
scripts without a magic number.
Remove all remaining references to it to avoid confusion.
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Upstream commit:
Date: Sun, 28 Nov 2010 20:44:37 +0800
[BUILTIN] Use EXEXIT in place of EXEXEC
The intended semantics of EXEXEC are identical to EXEXIT, so
simplify by using EXEXIT directly.
Functional change: in edge cases (exec within a trap handler),
this causes the exit status from exec not to be clobbered.
For example, without this patch:
$ sh -c 'trap "exec nonexistent" EXIT'; echo $?
exec: 1: nonexistent: not found
0
And with it:
$ sh -c 'trap "exec nonexistent" EXIT'; echo $?
exec: 1: nonexistent: not found
127
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Upstream commit 1 for ash:
[ERROR] Allow the originator of EXERROR to set the exit status
Some errors have exit status values specified by POSIX and it is
therefore desirable to be able to set the exit status at the EXERROR
source rather than in main.c.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Upstream commit 2 for ash:
[INPUT] Use exit status 127 when the script to run does not exist
This commit makes dash exit with return code 127 instead of 2 if
started as non-interactive shell with a non-existent command_file
specified as argument (or a directory), as documented in
http://www.opengroup.org/onlinepubs/009695399/utilities/sh.html#tag_04_128_14
The wrong exit code was reported by Clint Adams and Jari Aalto through
http://bugs.debian.org/548743http://bugs.debian.org/548687
Signed-off-by: Gerrit Pape <pape@smarden.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
NB: in fact, http://bugs.debian.org/548687 was not fixed by this:
"sh /dir/" thinks that EISDIR error on read is EOF, and exits 0.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
The commit 'ash: eval: Return status in eval functions' changed how
exit status is handled in eval functions. The case of nofork
applets was missed, resulting in the incorrect status potentially
being returned for nofork applets when FEATURE_SH_NOFORK is enabled.
Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Previous commit probably introduced a bug:
non-matching size calculation in size counting and
actual copying caused by SHELL_ALIGN being applied differently!
This won't bite if string sizes are also SHELL_ALIGNed.
Thus fixing.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Allocation addresses of malloc() are jittery,
thought I had a mem leak in hush, but it was malloc variability.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
The construct such as this:
t=1
export t
t=new_value1
had a small probability of momentarily using free()d value.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
dash has tokendlist[] array to decide which tokens end lists.
We store it as first byte of each tokname_array[i].
Switch to bit array, name it like dash (tokendlist), drop special
1st byte of tokname_array[i]. This brings us closer to dash, and
shrinks the binary, because many more string aliasing opportunities
are now open:
function old new delta
pstrcmp1 - 16 +16
readtoken1 2852 2858 +6
list 326 327 +1
pstrcmp 16 15 -1
tokname 45 42 -3
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 2/2 up/down: 23/-4) Total: 19 bytes
text data bss dec hex filename
943556 916 14292 958764 ea12c busybox_old
943463 916 14292 958671 ea0cf busybox_unstripped
^^^^^^^ note this!
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Upstream commit:
Date: Thu, 1 Jan 2015 07:53:10 +1100
expand: Fixed "$@" expansion when EXP_FULL is false
The commit 3c06acdac0b1ba0e0acdda513a57ee6e31385dce ([EXPAND]
Split unquoted $@/$* correctly when IFS is set but empty) broke
the case where $@ is in quotes and EXP_FULL is false.
In that case we should still emit IFS as field splitting is not
performed.
Reported-by: Juergen Daubert <jue@jue.li>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>