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| author | Herbert Xu <herbert@gondor.apana.org.au> | 2018-09-12 14:27:16 +0800 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2020-03-28 21:42:55 +0000 |
| commit | 1285f79afbd9686c78c7815203ecbf3e87a81ff8 (patch) | |
| tree | a9774dd1dbc1c389eeae8895c487157cf8ae5ce4 | |
| parent | d754d32592fa1c6359b37d101485ced1ff7cdf79 (diff) | |
| download | klibc-1285f79afbd9686c78c7815203ecbf3e87a81ff8.tar.gz | |
[klibc] dash: expand: Fix multiple issues with EXP_DISCARD in evalvar
[ dash commit a29e9a1738a4e7040211842f3f3d90e172fa58ce ]
The commit 3cd538634f71538370f5af239f342aec48b7470b broke parameter
expansion in multiple ways because the EXP_DISCARD flag wasn't set
or tested for various cases:
$ src/dash -c 'var=; echo ${var:+nonempty}'
nonempty
$ src/dash -u -c 'unset foo bar; echo ${foo+${bar}}'
dash: 1: bar: parameter not set
$ src/dash -c 'foo=bar; echo ${foo=BUG}; echo $foo'
barBUG
bar
$
This patch fixes them by introducing a new discard variable that
tracks whether the extra word should be discarded or not when it
is parsed.
Reported-by: Martijn Dekker <martijn@inlv.org>
Fixes: 3cd538634f71 ("expand: Do not reprocess data when...")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Reported-by: Martijn Dekker <martijn@inlv.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
| -rw-r--r-- | usr/dash/expand.c | 30 |
1 files changed, 16 insertions, 14 deletions
diff --git a/usr/dash/expand.c b/usr/dash/expand.c index 411381bd9960b..25236c09697d1 100644 --- a/usr/dash/expand.c +++ b/usr/dash/expand.c @@ -698,6 +698,7 @@ evalvar(char *p, int flag) int patloc; int startloc; ssize_t varlen; + int discard; int quoted; varflags = *p++; @@ -713,41 +714,41 @@ again: if (varflags & VSNUL) varlen--; + discard = varlen < 0 ? EXP_DISCARD : 0; + switch (subtype) { case VSPLUS: - varlen = -1 - varlen; + discard ^= EXP_DISCARD; /* fall through */ case 0: case VSMINUS: - p = argstr(p, flag | EXP_TILDE | EXP_WORD); - if (varlen < 0) - return p; + p = argstr(p, flag | EXP_TILDE | EXP_WORD | + (discard ^ EXP_DISCARD)); goto record; case VSASSIGN: case VSQUESTION: - if (varlen >= 0) - goto record; - p = subevalvar(p, var, 0, startloc, varflags, - flag & ~QUOTES_ESC); + (flag & ~QUOTES_ESC) | + (discard ^ EXP_DISCARD)); - if (flag & EXP_DISCARD) - return p; + if ((flag | ~discard) & EXP_DISCARD) + goto record; varflags &= ~VSNUL; + subtype = VSNORMAL; goto again; } - if (varlen < 0 && uflag) + if ((discard & ~flag) && uflag) varunset(p, var, 0, 0); if (subtype == VSLENGTH) { if (flag & EXP_DISCARD) return p; cvtnum(varlen > 0 ? varlen : 0, flag); - goto record; + goto really_record; } if (subtype == VSNORMAL) @@ -765,7 +766,7 @@ again: } #endif - flag |= varlen < 0 ? EXP_DISCARD : 0; + flag |= discard; if (!(flag & EXP_DISCARD)) { /* * Terminate the string and start recording the pattern @@ -778,9 +779,10 @@ again: p = subevalvar(p, NULL, patloc, startloc, varflags, flag); record: - if (flag & EXP_DISCARD) + if ((flag | discard) & EXP_DISCARD) return p; +really_record: if (quoted) { quoted = *var == '@' && shellparam.nparam; if (!quoted) |