ref-filter: implement '--contains' option

'tag -l' and 'branch -l' have two different ways of finding
out if a certain ref contains a commit. Implement both these
methods in ref-filter and give the caller of ref-filter API
the option to pick which implementation to be used.

'branch -l' uses 'is_descendant_of()' from commit.c which is
left as the default implementation to be used.

'tag -l' uses a more specific algorithm since ffc4b80. This
implementation is used whenever the 'with_commit_tag_algo' bit
is set in 'struct ref_filter'.

Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: Matthieu Moy <matthieu.moy@grenoble-inp.fr>
Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Karthik Nayak 2015-07-07 21:36:16 +05:30 committed by Junio C Hamano
parent f266c9163b
commit ee2bd06b0f
3 changed files with 121 additions and 1 deletions

View File

@ -86,6 +86,11 @@ static int in_commit_list(const struct commit_list *want, struct commit *c)
return 0;
}
/*
* The entire code segment for supporting the --contains option has been
* copied over to ref-filter.{c,h}. This will be deleted evetually when
* we port tag.c to use ref-filter APIs.
*/
enum contains_result {
CONTAINS_UNKNOWN = -1,
CONTAINS_NO = 0,

View File

@ -818,6 +818,114 @@ static void get_ref_atom_value(struct ref_array_item *ref, int atom, struct atom
*v = &ref->value[atom];
}
enum contains_result {
CONTAINS_UNKNOWN = -1,
CONTAINS_NO = 0,
CONTAINS_YES = 1
};
/*
* Mimicking the real stack, this stack lives on the heap, avoiding stack
* overflows.
*
* At each recursion step, the stack items points to the commits whose
* ancestors are to be inspected.
*/
struct contains_stack {
int nr, alloc;
struct contains_stack_entry {
struct commit *commit;
struct commit_list *parents;
} *contains_stack;
};
static int in_commit_list(const struct commit_list *want, struct commit *c)
{
for (; want; want = want->next)
if (!hashcmp(want->item->object.sha1, c->object.sha1))
return 1;
return 0;
}
/*
* Test whether the candidate or one of its parents is contained in the list.
* Do not recurse to find out, though, but return -1 if inconclusive.
*/
static enum contains_result contains_test(struct commit *candidate,
const struct commit_list *want)
{
/* was it previously marked as containing a want commit? */
if (candidate->object.flags & TMP_MARK)
return 1;
/* or marked as not possibly containing a want commit? */
if (candidate->object.flags & UNINTERESTING)
return 0;
/* or are we it? */
if (in_commit_list(want, candidate)) {
candidate->object.flags |= TMP_MARK;
return 1;
}
if (parse_commit(candidate) < 0)
return 0;
return -1;
}
static void push_to_contains_stack(struct commit *candidate, struct contains_stack *contains_stack)
{
ALLOC_GROW(contains_stack->contains_stack, contains_stack->nr + 1, contains_stack->alloc);
contains_stack->contains_stack[contains_stack->nr].commit = candidate;
contains_stack->contains_stack[contains_stack->nr++].parents = candidate->parents;
}
static enum contains_result contains_tag_algo(struct commit *candidate,
const struct commit_list *want)
{
struct contains_stack contains_stack = { 0, 0, NULL };
int result = contains_test(candidate, want);
if (result != CONTAINS_UNKNOWN)
return result;
push_to_contains_stack(candidate, &contains_stack);
while (contains_stack.nr) {
struct contains_stack_entry *entry = &contains_stack.contains_stack[contains_stack.nr - 1];
struct commit *commit = entry->commit;
struct commit_list *parents = entry->parents;
if (!parents) {
commit->object.flags |= UNINTERESTING;
contains_stack.nr--;
}
/*
* If we just popped the stack, parents->item has been marked,
* therefore contains_test will return a meaningful 0 or 1.
*/
else switch (contains_test(parents->item, want)) {
case CONTAINS_YES:
commit->object.flags |= TMP_MARK;
contains_stack.nr--;
break;
case CONTAINS_NO:
entry->parents = parents->next;
break;
case CONTAINS_UNKNOWN:
push_to_contains_stack(parents->item, &contains_stack);
break;
}
}
free(contains_stack.contains_stack);
return contains_test(candidate, want);
}
static int commit_contains(struct ref_filter *filter, struct commit *commit)
{
if (filter->with_commit_tag_algo)
return contains_tag_algo(commit, filter->with_commit);
return is_descendant_of(commit, filter->with_commit);
}
/*
* Return 1 if the refname matches one of the patterns, otherwise 0.
* A pattern can be path prefix (e.g. a refname "refs/heads/master"
@ -917,10 +1025,14 @@ static int ref_filter_handler(const char *refname, const struct object_id *oid,
* obtain the commit using the 'oid' available and discard all
* non-commits early. The actual filtering is done later.
*/
if (filter->merge_commit) {
if (filter->merge_commit || filter->with_commit) {
commit = lookup_commit_reference_gently(oid->hash, 1);
if (!commit)
return 0;
/* We perform the filtering for the '--contains' option */
if (filter->with_commit &&
!commit_contains(filter, commit))
return 0;
}
/*

View File

@ -44,6 +44,7 @@ struct ref_array {
struct ref_filter {
const char **name_patterns;
struct sha1_array points_at;
struct commit_list *with_commit;
enum {
REF_FILTER_MERGED_NONE = 0,
@ -51,6 +52,8 @@ struct ref_filter {
REF_FILTER_MERGED_OMIT
} merge;
struct commit *merge_commit;
unsigned int with_commit_tag_algo : 1;
};
struct ref_filter_cbdata {