hashmap.h: compare function has access to a data field

When using the hashmap a common need is to have access to caller provided
data in the compare function. A couple of times we abuse the keydata field
to pass in the data needed. This happens for example in patch-ids.c.

This patch changes the function signature of the compare function
to have one more void pointer available. The pointer given for each
invocation of the compare function must be defined in the init function
of the hashmap and is just passed through.

Documentation of this new feature is deferred to a later patch.
This is a rather mechanical conversion, just adding the new pass-through
parameter.  However while at it improve the naming of the fields of all
compare functions used by hashmaps by ensuring unused parameters are
prefixed with 'unused_' and naming the parameters what they are (instead
of 'unused' make it 'unused_keydata').

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Stefan Beller
2017-06-30 12:14:05 -07:00
committed by Junio C Hamano
parent e0aaa1b653
commit 7663cdc86c
19 changed files with 113 additions and 66 deletions

View File

@ -54,8 +54,10 @@ static const char *prio_names[] = {
N_("head"), N_("lightweight"), N_("annotated"),
};
static int commit_name_cmp(const struct commit_name *cn1,
const struct commit_name *cn2, const void *peeled)
static int commit_name_cmp(const void *unused_cmp_data,
const struct commit_name *cn1,
const struct commit_name *cn2,
const void *peeled)
{
return oidcmp(&cn1->peeled, peeled ? peeled : &cn2->peeled);
}
@ -501,7 +503,7 @@ int cmd_describe(int argc, const char **argv, const char *prefix)
return cmd_name_rev(args.argc, args.argv, prefix);
}
hashmap_init(&names, (hashmap_cmp_fn) commit_name_cmp, 0);
hashmap_init(&names, (hashmap_cmp_fn) commit_name_cmp, NULL, 0);
for_each_rawref(get_name, NULL);
if (!names.size && !always)
die(_("No names found, cannot describe anything."));