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author | Herbert Xu <herbert@gondor.apana.org.au> | 2018-09-12 14:27:16 +0800 |
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committer | Herbert Xu <herbert@gondor.apana.org.au> | 2018-11-19 18:59:50 +0800 |
commit | a29e9a1738a4e7040211842f3f3d90e172fa58ce (patch) | |
tree | de70cc7263b01399ad572aae01e0ae07aac76844 /src | |
parent | main: Print \n upon EOF (CTRL-D) when run interactively (diff) | |
download | dash-a29e9a1738a4e7040211842f3f3d90e172fa58ce.tar.gz dash-a29e9a1738a4e7040211842f3f3d90e172fa58ce.zip |
expand: Fix multiple issues with EXP_DISCARD in evalvar
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>
Diffstat (limited to 'src')
-rw-r--r-- | src/expand.c | 30 |
1 files changed, 16 insertions, 14 deletions
diff --git a/src/expand.c b/src/expand.c index 14daa63..856b7a9 100644 --- a/src/expand.c +++ b/src/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) |