git/list-objects-filter.h
Matthew DeVore e987df5fe6 list-objects-filter: implement composite filters
Allow combining filters such that only objects accepted by all filters
are shown. The motivation for this is to allow getting directory
listings without also fetching blobs. This can be done by combining
blob:none with tree:<depth>. There are massive repositories that have
larger-than-expected trees - even if you include only a single commit.

A combined filter supports any number of subfilters, and is written in
the following form:

	combine:<filter 1>+<filter 2>+<filter 3>

Certain non-alphanumeric characters in each filter must be
URL-encoded.

For now, combined filters must be specified in this form. In a
subsequent commit, rev-list will support multiple --filter arguments
which will have the same effect as specifying one filter argument
starting with "combine:". The documentation will be updated in that
commit, as the URL-encoding scheme is in general not meant to be used
directly by the user, and it is better to describe the URL-encoding
feature in terms of the repeated flag.

Helped-by: Emily Shaffer <emilyshaffer@google.com>
Helped-by: Jeff Hostetler <git@jeffhostetler.com>
Helped-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Helped-by: Jonathan Tan <jonathantanmy@google.com>
Helped-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Matthew DeVore <matvore@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-06-28 08:41:53 -07:00

95 lines
3.2 KiB
C

#ifndef LIST_OBJECTS_FILTER_H
#define LIST_OBJECTS_FILTER_H
struct list_objects_filter_options;
struct object;
struct oidset;
struct repository;
/*
* During list-object traversal we allow certain objects to be
* filtered (omitted) from the result. The active filter uses
* these result values to guide list-objects.
*
* _ZERO : Do nothing with the object at this time. It may
* be revisited if it appears in another place in
* the tree or in another commit during the overall
* traversal.
*
* _MARK_SEEN : Mark this object as "SEEN" in the object flags.
* This will prevent it from being revisited during
* the remainder of the traversal. This DOES NOT
* imply that it will be included in the results.
*
* _DO_SHOW : Show this object in the results (call show() on it).
* In general, objects should only be shown once, but
* this result DOES NOT imply that we mark it SEEN.
*
* _SKIP_TREE : Used in LOFS_BEGIN_TREE situation - indicates that
* the tree's children should not be iterated over. This
* is used as an optimization when all children will
* definitely be ignored.
*
* Most of the time, you want the combination (_MARK_SEEN | _DO_SHOW)
* but they can be used independently, such as when sparse-checkout
* pattern matching is being applied.
*
* A _MARK_SEEN without _DO_SHOW can be called a hard-omit -- the
* object is not shown and will never be reconsidered (unless a
* previous iteration has already shown it).
*
* A _DO_SHOW without _MARK_SEEN can be used, for example, to
* include a directory, but then revisit it to selectively include
* or omit objects within it.
*
* A _ZERO can be called a provisional-omit -- the object is NOT shown,
* but *may* be revisited (if the object appears again in the traversal).
* Therefore, it will be omitted from the results *unless* a later
* iteration causes it to be shown.
*/
enum list_objects_filter_result {
LOFR_ZERO = 0,
LOFR_MARK_SEEN = 1<<0,
LOFR_DO_SHOW = 1<<1,
LOFR_SKIP_TREE = 1<<2,
};
enum list_objects_filter_situation {
LOFS_BEGIN_TREE,
LOFS_END_TREE,
LOFS_BLOB
};
struct filter;
/*
* Constructor for the set of defined list-objects filters.
* The `omitted` set is optional. It is populated with objects that the
* filter excludes. This set should not be considered finalized until
* after list_objects_filter__free is called on the returned `struct
* filter *`.
*/
struct filter *list_objects_filter__init(
struct oidset *omitted,
struct list_objects_filter_options *filter_options);
/*
* Lets `filter` decide how to handle the `obj`. If `filter` is NULL, this
* function behaves as expected if no filter is configured: all objects are
* included.
*/
enum list_objects_filter_result list_objects_filter__filter_object(
struct repository *r,
enum list_objects_filter_situation filter_situation,
struct object *obj,
const char *pathname,
const char *filename,
struct filter *filter);
/*
* Destroys `filter` and finalizes the `omitted` set, if present. Does
* nothing if `filter` is null.
*/
void list_objects_filter__free(struct filter *filter);
#endif /* LIST_OBJECTS_FILTER_H */