get with cas token fails to fetch all results

[andreiz]

Description:

When performing a get with a cas token requested a multi-get is performed
internally. After doing so
only the first result is fetched, leaving the final RES_END result on the
stack.
As per the
libmemcached documentation memcached_fetch_result should be called until it

returns NULL following a
multi-get.

In some circumstances this is not noticeable as libmemcached takes care of

flushing the receive buffers
accordingly, however certain subsequent operations will incorrectly return
the
left-over RES_END result.
I have seen this behaviour exhibited when performing a get with cas token
request followed by an add
operation though there may be other examples.

I have tested this with memcached extension version 2.0.0b2 using
libmemcached
0.53 and 1.0.2, though I
believe the issue also exists with earlier versions.

Please find attached a patch against 2.0.0b2 to address this issue which
both
resolves the primary issue
and also simplifies the call in the case that a cas token is not required
by
calling
memcached_get_by_key.

[mkoppanen]

This has been fixed