git/pseudo-merge.h

217 lines
6.1 KiB
C

#ifndef PSEUDO_MERGE_H
#define PSEUDO_MERGE_H
#include "git-compat-util.h"
#include "strmap.h"
#include "khash.h"
#include "ewah/ewok.h"
struct commit;
struct string_list;
struct bitmap_index;
struct bitmap_writer;
struct repository;
/*
* A pseudo-merge group tracks the set of non-bitmapped reference tips
* that match the given pattern.
*
* Within those matches, they are further segmented by separating
* consecutive capture groups with '-' dash character capture groups
* with '-' dash characters.
*
* Those groups are then ordered by committer date and partitioned
* into individual pseudo-merge(s) according to the decay, max_merges,
* sample_rate, and threshold parameters.
*/
struct pseudo_merge_group {
regex_t *pattern;
/* capture group(s) -> struct pseudo_merge_matches */
struct strmap matches;
/*
* The individual pseudo-merge(s) that are generated from the
* above array of matches, partitioned according to the below
* parameters.
*/
struct commit **merges;
size_t merges_nr;
size_t merges_alloc;
/*
* Pseudo-merge grouping parameters. See git-config(1) for
* more information.
*/
double decay;
int max_merges;
double sample_rate;
int stable_size;
timestamp_t threshold;
timestamp_t stable_threshold;
};
struct pseudo_merge_matches {
struct commit **stable;
struct commit **unstable;
size_t stable_nr, stable_alloc;
size_t unstable_nr, unstable_alloc;
};
/*
* Read the repository's configuration:
*
* - bitmapPseudoMerge.<name>.pattern
* - bitmapPseudoMerge.<name>.decay
* - bitmapPseudoMerge.<name>.sampleRate
* - bitmapPseudoMerge.<name>.threshold
* - bitmapPseudoMerge.<name>.maxMerges
* - bitmapPseudoMerge.<name>.stableThreshold
* - bitmapPseudoMerge.<name>.stableSize
*
* and populates the given `list` with pseudo-merge groups. String
* entry keys are the pseudo-merge group names, and the values are
* pointers to the pseudo_merge_group structure itself.
*/
void load_pseudo_merges_from_config(struct repository *r, struct string_list *list);
/*
* A pseudo-merge commit index (pseudo_merge_commit_idx) maps a
* particular (non-pseudo-merge) commit to the list of pseudo-merge(s)
* it appears in.
*/
struct pseudo_merge_commit_idx {
uint32_t *pseudo_merge;
size_t nr, alloc;
};
/*
* Selects pseudo-merges from a list of commits, populating the given
* string_list of pseudo-merge groups.
*
* Populates the pseudo_merge_commits map with a commit_idx
* corresponding to each commit in the list. Counts the total number
* of pseudo-merges generated.
*
* Optionally shows a progress meter.
*/
void select_pseudo_merges(struct bitmap_writer *writer);
/*
* Represents a serialized view of a file containing pseudo-merge(s)
* (see Documentation/technical/bitmap-format.txt for a specification
* of the format).
*/
struct pseudo_merge_map {
/*
* An array of pseudo-merge(s), lazily loaded from the .bitmap
* file.
*/
struct pseudo_merge *v;
size_t nr;
size_t commits_nr;
/*
* Pointers into a memory-mapped view of the .bitmap file:
*
* - map: the beginning of the .bitmap file
* - commits: the beginning of the pseudo-merge commit index
* - map_size: the size of the .bitmap file
*/
const unsigned char *map;
const unsigned char *commits;
size_t map_size;
};
/*
* An individual pseudo-merge, storing a pair of lazily-loaded
* bitmaps:
*
* - commits: the set of commit(s) that are part of the pseudo-merge
* - bitmap: the set of object(s) reachable from the above set of
* commits.
*
* The `at` and `bitmap_at` fields are used to store the locations of
* each of the above bitmaps in the .bitmap file.
*/
struct pseudo_merge {
struct ewah_bitmap *commits;
struct ewah_bitmap *bitmap;
off_t at;
off_t bitmap_at;
/*
* `satisfied` indicates whether the given pseudo-merge has been
* used.
*
* `loaded_commits` and `loaded_bitmap` indicate whether the
* respective bitmaps have been loaded and read from the
* .bitmap file.
*/
unsigned satisfied : 1,
loaded_commits : 1,
loaded_bitmap : 1;
};
/*
* Frees the given pseudo-merge map, releasing any memory held by (a)
* parsed EWAH bitmaps, or (b) the array of pseudo-merges itself. Does
* not free the memory-mapped view of the .bitmap file.
*/
void free_pseudo_merge_map(struct pseudo_merge_map *pm);
/*
* Loads the bitmap corresponding to the given pseudo-merge from the
* map, if it has not already been loaded.
*/
struct ewah_bitmap *pseudo_merge_bitmap(const struct pseudo_merge_map *pm,
struct pseudo_merge *merge);
/*
* Loads the pseudo-merge and its commits bitmap from the given
* pseudo-merge map, if it has not already been loaded.
*/
struct pseudo_merge *use_pseudo_merge(const struct pseudo_merge_map *pm,
struct pseudo_merge *merge);
/*
* Applies pseudo-merge(s) containing the given commit to the bitmap
* "result".
*
* If any pseudo-merge(s) were satisfied, returns the number
* satisfied, otherwise returns 0. If any were satisfied, the
* remaining unsatisfied pseudo-merges are cascaded (see below).
*/
int apply_pseudo_merges_for_commit(const struct pseudo_merge_map *pm,
struct bitmap *result,
struct commit *commit, uint32_t commit_pos);
/*
* Applies pseudo-merge(s) which are satisfied according to the
* current bitmap in result (or roots, see below). If any
* pseudo-merges were satisfied, repeat the process over unsatisfied
* pseudo-merge commits until no more pseudo-merges are satisfied.
*
* Result is the bitmap to which the pseudo-merge(s) are applied.
* Roots (if given) is a bitmap of the traversal tip(s) for either
* side of a reachability traversal.
*
* Roots may given instead of a populated results bitmap at the
* beginning of a traversal on either side where the reachability
* closure over tips is not yet known.
*/
int cascade_pseudo_merges(const struct pseudo_merge_map *pm,
struct bitmap *result,
struct bitmap *roots);
/*
* Returns a pseudo-merge which contains the exact set of commits
* listed in the "parents" bitamp, or NULL if none could be found.
*/
struct pseudo_merge *pseudo_merge_for_parents(const struct pseudo_merge_map *pm,
struct bitmap *parents);
#endif