With bash's read builtin it is possible to read from a file (e.g.
device-tree) until the first '\0' character:
IFS= read -r -d '' VARIABLE < file
In busybox ash the -d extension is also implemented, but checking the
read character for '\0' has to be performed after comparing with the
delimiter.
Signed-off-by: Christian Eggers <ceggers@arri.de>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Upstream commit:
Date: Sun, 11 Nov 2007 15:27:00 +0800
Expand here-documents in the current shell environment
Previously we always expanded here-documents in a subshell. This is
contrary to the POSIX specification and how other shells behave. What's
more this slows down many expansions due to the extra fork (however, it
must be said that it is possible for it speed up certain expansions by
running it simultaneously with the command on two CPUs).
This patch move the expansion into the current shell environment.
Test case:
unset a
cat <<- EOF > /dev/null
${a=NOT}
EOF
echo ${a}BAD
Old result:
BAD
New result:
NOTBAD
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Upstream commit:
Date: Fri, 1 Jun 2018 18:25:29 +0800
expand: Ensure result is escaped in cvtnum
The minus sign generated from arithmetic expansion is currently
unquoted which causes anomalies when the result is used in where
the quoting matters.
This patch fixes it by explicitly calling memtodest on the result
in cvtnum.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Upstream commit:
Date: Sat, 19 May 2018 02:39:54 +0800
eval: Fail immediately with redirections errors for simple command
Previously, dash would continue to perform variable expansions
even if a redirection error occured. This patch changes it so
that it fails immediately.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Upstream commit:
Date: Mon, 29 Apr 2019 19:13:37 +0500
expand: Fix trailing newlines processing in backquote expanding
According to POSIX.1-2008 we should remove newlines only at the end of
the substitution. Newlines-only substitions causes dash to remove
newlines before beggining of the substitution. The following code:
cat <<END
1
$(echo "")
2
END
prints "1<newline>2" instead of expected "1<newline><newline>2".
This patch fixes trailing newlines processing in backquote expanding.
Signed-off-by: Nikolai Merinov <n.merinov@inango-systems.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Upstream commit:
Date: Mon, 27 May 2019 13:39:37 +0800
parser: Only accept single-digit parameter expansion outside of braces
This patch should fix the problem.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Upstream commit:
Date: Mon Oct 6 10:39:47 2014 +0800
[BUILTIN] Exit without arguments in a trap should use status outside traps
POSIX now requires that exit without arguments in a trap should
return the last command status prior to executing traps. This
patch implements this behaviour.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Upstream commit:
Date: Wed, 28 Mar 2018 18:37:51 +0800
expand: Do not quote backslashes in unquoted parameter expansion
Here is a better example:
a="/*/\nullx" b="/*/\null"; printf "%s\n" $a $b
dash currently prints
/*/\nullx
/*/\null
bash prints
/*/\nullx
/dev/null
You may argue the bash behaviour is inconsistent but it actually
makes sense. What happens is that quote removal only applies to
the original token as seen by the shell. It is never applied to
the result of parameter expansion.
Now you may ask why on earth does the second line say "/dev/null"
instead of "/dev/\null". Well that's because it is not the quote
removal step that removed the backslash, but the pathname expansion.
The fact that the /de\v does not become /dev even though it exists
is just the result of the optimisation to avoid unnecessarily
calling stat(2). I have checked POSIX and I don't see anything
that forbids this behaviour.
So going back to dash yes I think we should adopt the bash behaviour
for pathname expansion and keep the existing case semantics.
This patch does exactly that. Note that this patch does not work
unless you have already applied
https://patchwork.kernel.org/patch/10306507/
because otherwise the optimisation mentioned above does not get
detected correctly and we will end up doing quote removal twice.
This patch also updates expmeta to handle naked backslashes at
the end of the pattern which is now possible.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
function old new delta
expmeta 618 653 +35
memtodest 146 147 +1
Tested to work with both ASH_INTERNAL_GLOB on and off.
hush does not handle this correctly.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Upstream commit:
Date: Fri, 23 Mar 2018 18:58:47 +0800
expand: Fix ghost fields with unquoted $@/$*
You're right. The proper fix to this is to ensure that nulonly
is not set in varvalue for $*. It should only be set for $@ when
it's inside double quotes.
In fact there is another bug while we're playing with $@/$*.
When IFS is set to a non-whitespace character such as :, $*
outside quotes won't remove empty fields as it should.
This patch fixes both problems.
Reported-by: Martijn Dekker <martijn@inlv.org>
Suggested-by: Harald van Dijk <harald@gigawatt.nl>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
function old new delta
argstr 1111 1113 +2
evalvar 571 569 -2
varvalue 579 576 -3
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/2 up/down: 2/-5) Total: -3 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Upstream commit:
Date: Wed, 4 Apr 2018 17:54:01 +0800
eval: Variable assignments on functions are no longer persistent
Dirk Fieldhouse <fieldhouse@gmx.net> wrote:
> In POSIX.1-2017 ("simultaneously IEEE Std 1003.1™-2017 and The Open
> Group Technical Standard Base Specifications, Issue 7")
> <http://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#tag_18_09>,
> we read under '2.9.1 Simple Commands'
>
> "Variable assignments shall be performed as follows:
> ...
> - If the command name is a standard utility implemented as a function
> (see XBD Utility), the effect of variable assignments shall be as if the
> utility was not implemented as a function.
> ...
> - If the command name is a function that is not a standard utility
> implemented as a function, variable assignments shall affect the current
> execution environment during the execution of the function. It is
> unspecified:
>
> * Whether or not the variable assignments persist after the
> completion of the function
>
> * Whether or not the variables gain the export attribute during
> the execution of the function
>
> * Whether or not export attributes gained as a result of the
> variable assignments persist after the completion of the function (if
> variable assignments persist after the completion of the function)"
POSIX used to require the current dash behaviour. However, you're
right that this is no longer the case.
This patch will remove the persistence of the variable assignment.
I have considered the exporting the variables during the function
execution but have decided against it because:
1) It makes the code bigger.
2) dash has never done this in the past.
3) You cannot use this portably anyway.
Reported-by: Dirk Fieldhouse <fieldhouse@gmx.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
function old new delta
evalcommand 1606 1635 +29
evalcase 313 317 +4
evalfun 280 268 -12
pushlocalvars 48 - -48
------------------------------------------------------------------------------
(add/remove: 0/1 grow/shrink: 2/1 up/down: 33/-60) Total: -27 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This necessitates switch from libc FILE api to a simple
homegrown replacement.
The change which fixes the bug here is the deleting of
restore_redirected_FILEs();
line. It was prematurely moving (restoring) script fd#3.
The fix is: we don't even _want_ to restore scrit fds,
we are perfectly fine with them being moved.
The only reason we tried to restore them is that FILE api
did not allow moving of FILE->fd.
function old new delta
refill_HFILE_and_getc - 93 +93
hfopen - 90 +90
hfclose - 66 +66
pseudo_exec_argv 591 597 +6
hush_main 1089 1095 +6
builtin_source 209 214 +5
save_fd_on_redirect 197 200 +3
setup_redirects 320 321 +1
fgetc_interactive 235 236 +1
i_peek_and_eat_bkslash_nl 99 97 -2
expand_vars_to_list 1103 1100 -3
restore_redirects 99 52 -47
fclose_and_forget 57 - -57
remember_FILE 63 - -63
------------------------------------------------------------------------------
(add/remove: 3/2 grow/shrink: 6/3 up/down: 271/-172) Total: 99 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This wasn't an ash bug in dollar_altvalue9, it was hush bug (and bash!)
function old new delta
expand_one_var 2236 2254 +18
expand_vars_to_list 1097 1103 +6
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/0 up/down: 24/0) Total: 24 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
ash might be a bit buggy, need to investigate dollar_altvalue9 test
function old new delta
expand_one_var 1639 2236 +597
expand_variables 112 128 +16
expand_vars_to_list 1117 1097 -20
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/1 up/down: 613/-20) Total: 593 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Upstream commit:
Date: Thu, 22 Mar 2018 21:41:24 +0800
parser: Allow newlines within parameter substitution
On Fri, Mar 16, 2018 at 11:27:22AM +0800, Herbert Xu wrote:
> On Thu, Mar 15, 2018 at 10:49:15PM +0100, Harald van Dijk wrote:
> >
> > Okay, it can be trivially modified to something that does work in other
> > shells (even if it were actually executed), but gets rejected at parse time
> > by dash:
> >
> > if false; then
> > : ${$+
> > }
> > fi
>
> That's just a bug in dash's parser with ${} in general, because
> it bombs out without the if clause too:
>
> : ${$+
> }
This patch fixes the parsing of newlines with parameter substitution.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
newer bash does not drop it, most other shells too
function old new delta
unbackslash 39 57 +18
parse_stream 2753 2751 -2
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/1 up/down: 18/-2) Total: 16 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Upstream email:
parser: Fix parameter expansion inside inner double quotes
The parsing of parameter expansion inside inner double quotes
breaks because we never look for ENDVAR while innerdq is true.
echo "${x#"${x+''}"''}
This patch fixes it by pushing the syntax stack if innerdq is
true and we enter a new parameter expansion.
This patch also fixes a corner case where a bad substitution error
occurs within arithmetic expansion.
Reported-by: Denys Vlasenko <vda.linux@googlemail.com>
Fixes: ab1cecb40478 (" parser: Add syntax stack for recursive...")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
function old new delta
readtoken1 2880 2898 +18
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Upstream email:
This is actually composed of two bugs. First of all our tracking
of quotemark is wrong so anything after "$@" becomes quoted. Once
we fix that then the problem is that the first space character
after "$@" is not recognised as an IFS.
This patch fixes both.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Upstream commit:
From: Herbert Xu <herbert@gondor.apana.org.au>
Date: Fri, 9 Mar 2018 23:07:53 +0800
parser: Fix single-quoted patterns in here-documents
The script
x=*
cat <<- EOF
${x#'*'}
EOF
prints * instead of nothing as it should. The problem is that
when we're in sqsyntax context in a here-document, we won't add
CTLESC as we should. This patch fixes it:
Reported-by: Harald van Dijk <harald@gigawatt.nl>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This closes 10821.
Upstream patch:
From: Herbert Xu <herbert@gondor.apana.org.au>
Date: Fri, 9 Mar 2018 00:14:02 +0800
parser: Add syntax stack for recursive parsing
Without a stack of syntaxes we cannot correctly these two cases
together:
"${a#'$$'}"
"${a#"${b-'$$'}"}"
A recursive parser also helps in some other corner cases such
as nested arithmetic expansion with paratheses.
This patch adds a syntax stack allocated from the stack using
alloca. As a side-effect this allows us to remove the naked
backslashes for patterns within double-quotes, which means that
EXP_QPAT also has to go.
This patch also fixes removes any backslashes that precede right
braces when they are present within a parameter expansion context,
and backslashes that precede double quotes within inner double
quotes inside a parameter expansion in a here-document context.
The idea of a recursive parser is based on a patch by Harald van
Dijk.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
var_bash3, var_bash4 and var_bash6 tests are updated
with the output given by bash-4.3.43
With this patch, the following tests now pass for ash:
dollar_repl_slash_bash2.tests
squote_in_varexp2.tests
squote_in_varexp.tests
var_bash4.tests
function old new delta
readtoken1 2615 2874 +259
synstack_push - 54 +54
evalvar 574 571 -3
rmescapes 330 310 -20
subevalvar 1279 1258 -21
argstr 1146 1107 -39
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 1/4 up/down: 313/-83) Total: 230 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Upstream commit:
Author: Herbert Xu <herbert@gondor.apana.org.au>
Date: Thu Mar 15 18:27:30 2018 +0800
parser: Fix backquote support in here-document EOF mark
Currently using backquotes in a here-document EOF mark is broken
because dash tries to do command substitution on it. This patch
fixes it by checking whether we're looking for an EOF mark during
tokenisation.
Reported-by: Harald van Dijk <harald@gigawatt.nl>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
With added fix for quoted-ness of the EOF mark.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Part of upstream commit:
Date: Thu Mar 8 08:37:11 2018 +0100
Author: Harald van Dijk <harald@gigawatt.nl>
parser: use pgetc_eatbnl() in more places
dash has a pgetc_eatbnl function in parser.c which skips any
backslash-newline combinations. It's not used everywhere it could be.
There is also some duplicated backslash-newline handling elsewhere in
parser.c. Replace most of the calls to pgetc() with calls to
pgetc_eatbnl() and remove the duplicated backslash-newline handling.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Not adding "readtoken1(pgetc_eatbnl(), DQSYNTAX..." changes, since
readtoken1() handles the "starts with backslash + newline" case itself.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Based on a patch by Mark Marshall <mark.marshall@omicronenergy.com>
function old new delta
dup_CLOEXEC - 49 +49
fcntl_F_DUPFD 46 - -46
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
