#159 Don't try to unpack empty associated strings

[Eckhart Wörner]

This bug has been copied over from http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=603868

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If the length of the associated strings section is 0, libwv2 currently tries to
unpack it anyway, which tries to interpret whatever is after that point in the
files as a table of strings. In some cases (such as the attached example
document) this results in garbage values for the metadata.

I've attached a patch to fix this by special casing when this size is 0.

I created the test document from scratch - I'm happy to license it under the
same licence as libwv2 if someone wants to use it in a testsuite.

Cheers,
Olly

[Eckhart Wörner]

Proposed patch

[Eckhart Wörner]

Test case