This allows hostnames to contain uppercase characters, matching behavior
in Docker versions before 1.10. It does not attempt to canonicalize
hostnames into a lowercase format before parsing, since this could lead
to corner cases (for example, making Hostname.Domain.Com/ref ambiguous
on a daemon which contains references for both hostname.domain.com/ref
and Hostname.Domain.Com/ref).
Fixes: #1433
Signed-off-by: Aaron Lehmann <aaron.lehmann@docker.com>
To resolve some inconsistencies between the grammar and the regular
expressions, the grammar has been slightly refactored to match the intent. The
regular expressions have been redefined with the same structure to make it
easier to verify the grammar is correct.
Signed-off-by: Stephen J Day <stephen.day@docker.com>
In order to support valid hostnames as name components, supporting repeated dash was added.
Additionally double underscore is now allowed as a separator to loosen the restriction for previously supported names.
Signed-off-by: Derek McGowan <derek@mcgstyle.net> (github: dmcgowan)
