On 03/01/2014 05:10 PM, Simon Glass wrote:
Hi Stephen,
On 27 February 2014 22:00, Stephen Warren <swarren@wwwdotorg.org mailto:swarren@wwwdotorg.org> wrote:
The following shell command fails: if test -z "$x"; then echo "zero"; else echo "non-zero"; fi (assuming $x does not exist, it prints "non-zero" rather than "zero"). ... since "$x" expands to nothing, and the argument is completely dropped, causing too few to be passed to -z, causing cmd_test() to error out early. This is because when variable expansions are processed by make_string(), the expanded results are concatenated back into a new string. However, no quoting is applied when doing so, so any empty variables simply don't generate any parameter when the combined string is parsed again. Fix this by explicitly replacing quoting any argument that was originally quoted when re-generating a string from the already-parsed argument list. This also fixes loss of whitespace in commands such as: setenv space " " setenv var " 1${space}${space} 2 " echo ">>${var}<<"Is there an upstream still for hush, or are we so far away that it doesn't matter? If there is, was this bug fixed there?
Well, the comments at the head of the file say it came from Busybox, but it's obviously diverged massively since it was imported:
$ wc -l busybox/shell/hush.c u-boot/common/hush.c 9156 busybox/shell/hush.c 3682 u-boot/common/hush.c $ diff -u busybox/shell/hush.c u-boot/common/hush.c|wc -l 12264
Also, the function this patch touches doesn't seem to exist under that name any more. From a quick look at the source, I couldn't tell what the equivalent is.
Perhaps replaying patches to that file in Busybox since the fork might be more useful.
A quick Google search for "hush" or "hush shell" doesn't seem to yield any other alternative upstreams.
diff --git a/common/hush.c b/common/hush.c index 3f3a79c..66ece41 100644 --- a/common/hush.c +++ b/common/hush.c @@ -221,6 +221,7 @@ struct child_prog { pid_t pid; /* 0 if exited */ #endif char **argv; /* program name and arguments */ + int *argv_nonnull;This could do with a comment.
I did wonder if I should name this "quoted". I'd originally shied away from this to prevent changing the terminology, but since hush.c has diverged so much, perhaps that wouldn't be an issue...