refs: loosen restriction on wildcard "*" refspecs

Loosen restrictions on refspecs by allowing patterns that have a "*"
within a component instead of only as the whole component.

Remove the logic to accept a single "*" as a whole component from
check_refname_format(), and implement an extended form of that logic
in check_refname_component().  Pass the pointer to the flags argument
to the latter, as it has to clear REFNAME_REFSPEC_PATTERN bit when
it sees "*".

Teach check_refname_component() function to allow an asterisk "*"
only when REFNAME_REFSPEC_PATTERN is set in the flags, and drop the
bit after seeing a "*", to ensure that one side of a refspec
contains at most one asterisk.

This will allow us to accept refspecs such as `for/bar*:foo/baz*`.
Any refspec which functioned before shall continue functioning with
the new logic.

Signed-off-by: Jacob Keller <jacob.keller@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/refs.h b/refs.h
index cf642e6dd..417f2c8ff 100644
--- a/refs.h
+++ b/refs.h
@@ -224,8 +224,8 @@ extern int for_each_reflog(each_ref_fn, void *);
  * to the rules described in Documentation/git-check-ref-format.txt.
  * If REFNAME_ALLOW_ONELEVEL is set in flags, then accept one-level
  * reference names.  If REFNAME_REFSPEC_PATTERN is set in flags, then
- * allow a "*" wildcard character in place of one of the name
- * components.  No leading or repeated slashes are accepted.
+ * allow a single "*" wildcard character in the refspec. No leading or
+ * repeated slashes are accepted.
  */
 extern int check_refname_format(const char *refname, int flags);