Graeme Hewson wrote:
In the updated documentation for display filters, I say when talking
about slices:
Lengths can be negative too, in which case they mean the same as a
negative
end offset. Thus, the following are equivalent:
frame[-4:2] == 0.1
frame[-4--3] == 0.1
frame[-4:-3] == 0.1
Are negative slice lengths useful? I would suggest not.
No replies to this, so here's a series of patches to disallow negative
slice lengths and fix a few other things.
scanner.l
Use gint32 instead of guint32 and strtol() instead of strtoul()
for signed integers.
Pathological slice specifications could cause Flex default rule
to be invoked, echoing characters to stdout.
Example: frame[0foo]==1
syntax-tree.h
syntax-tree.c
Use gint32 instead of guint32 for node data.
semcheck.c
Check slice lengths as well as offsets. Disallow negative/zero
lengths.
Range on RHS of display filter expression wasn't being checked in
every case.
ftypes.c
Fix assertion failure when absolute value of negative slice
offset > field length.
Remove code for handling negative slice lengths.
ethereal-filter.pod.template
Remove reference to negative slice lengths.
Clean and polish.
Graeme Hewson
Attachment:
dfilter.tar.gz
Description: application/gzip
