filter: compose safety Tag and fix write offset (#993)
filter: compose safety Tag and fix write offset (#993)

Filter was trusting that input plugins was ingesting a NULL terminated
value, but if the data comes from Forward this will not be the case and
when calling the Routing will not match any rule.

This patch add a safety tag composer plus fix a problem when setting up
the write position when data has been removed.

Signed-off-by: Eduardo Silva <81f705dc2ce1a61a2621e0e4b442a9474e1d0c70@treasure-data.com>

nokute78/fluent-bit,fluent/fluent-bit,fluent/fluent-bit,nokute78/fluent-bit,nokute78/fluent-bit,nokute78/fluent-bit,nokute78/fluent-bit,fluent/fluent-bit,fluent/fluent-bit,fluent/fluent-bit,nokute78/fluent-bit,fluent/fluent-bit,fluent/fluent-bit,nokute78/fluent-bit,nokute78/fluent-bit,fluent/fluent-bit,fluent/fluent-bit,nokute78/fluent-bit,fluent/fluent-bit,fluent/fluent-bit,nokute78/fluent-bit,nokute78/fluent-bit,nokute78/fluent-bit,fluent/fluent-bit