Andrew's git - gitweb.git/blob

   1#ifndef BLAME_H
   2#define BLAME_H
   3
   4#include "cache.h"
   5#include "commit.h"
   6#include "xdiff-interface.h"
   7#include "revision.h"
   8#include "prio-queue.h"
   9#include "diff.h"
  10
  11#define PICKAXE_BLAME_MOVE              01
  12#define PICKAXE_BLAME_COPY              02
  13#define PICKAXE_BLAME_COPY_HARDER       04
  14#define PICKAXE_BLAME_COPY_HARDEST      010
  15
  16#define BLAME_DEFAULT_MOVE_SCORE        20
  17#define BLAME_DEFAULT_COPY_SCORE        40
  18
  19/*
  20 * One blob in a commit that is being suspected
  21 */
  22struct blame_origin {
  23        int refcnt;
  24        /* Record preceding blame record for this blob */
  25        struct blame_origin *previous;
  26        /* origins are put in a list linked via `next' hanging off the
  27         * corresponding commit's util field in order to make finding
  28         * them fast.  The presence in this chain does not count
  29         * towards the origin's reference count.  It is tempting to
  30         * let it count as long as the commit is pending examination,
  31         * but even under circumstances where the commit will be
  32         * present multiple times in the priority queue of unexamined
  33         * commits, processing the first instance will not leave any
  34         * work requiring the origin data for the second instance.  An
  35         * interspersed commit changing that would have to be
  36         * preexisting with a different ancestry and with the same
  37         * commit date in order to wedge itself between two instances
  38         * of the same commit in the priority queue _and_ produce
  39         * blame entries relevant for it.  While we don't want to let
  40         * us get tripped up by this case, it certainly does not seem
  41         * worth optimizing for.
  42         */
  43        struct blame_origin *next;
  44        struct commit *commit;
  45        /* `suspects' contains blame entries that may be attributed to
  46         * this origin's commit or to parent commits.  When a commit
  47         * is being processed, all suspects will be moved, either by
  48         * assigning them to an origin in a different commit, or by
  49         * shipping them to the scoreboard's ent list because they
  50         * cannot be attributed to a different commit.
  51         */
  52        struct blame_entry *suspects;
  53        mmfile_t file;
  54        struct object_id blob_oid;
  55        unsigned short mode;
  56        /* guilty gets set when shipping any suspects to the final
  57         * blame list instead of other commits
  58         */
  59        char guilty;
  60        char path[FLEX_ARRAY];
  61};
  62
  63/*
  64 * Each group of lines is described by a blame_entry; it can be split
  65 * as we pass blame to the parents.  They are arranged in linked lists
  66 * kept as `suspects' of some unprocessed origin, or entered (when the
  67 * blame origin has been finalized) into the scoreboard structure.
  68 * While the scoreboard structure is only sorted at the end of
  69 * processing (according to final image line number), the lists
  70 * attached to an origin are sorted by the target line number.
  71 */
  72struct blame_entry {
  73        struct blame_entry *next;
  74
  75        /* the first line of this group in the final image;
  76         * internally all line numbers are 0 based.
  77         */
  78        int lno;
  79
  80        /* how many lines this group has */
  81        int num_lines;
  82
  83        /* the commit that introduced this group into the final image */
  84        struct blame_origin *suspect;
  85
  86        /* the line number of the first line of this group in the
  87         * suspect's file; internally all line numbers are 0 based.
  88         */
  89        int s_lno;
  90
  91        /* how significant this entry is -- cached to avoid
  92         * scanning the lines over and over.
  93         */
  94        unsigned score;
  95};
  96
  97/*
  98 * The current state of the blame assignment.
  99 */
 100struct blame_scoreboard {
 101        /* the final commit (i.e. where we started digging from) */
 102        struct commit *final;
 103        /* Priority queue for commits with unassigned blame records */
 104        struct prio_queue commits;
 105        struct repository *repo;
 106        struct rev_info *revs;
 107        const char *path;
 108
 109        /*
 110         * The contents in the final image.
 111         * Used by many functions to obtain contents of the nth line,
 112         * indexed with scoreboard.lineno[blame_entry.lno].
 113         */
 114        const char *final_buf;
 115        unsigned long final_buf_size;
 116
 117        /* linked list of blames */
 118        struct blame_entry *ent;
 119
 120        /* look-up a line in the final buffer */
 121        int num_lines;
 122        int *lineno;
 123
 124        /* stats */
 125        int num_read_blob;
 126        int num_get_patch;
 127        int num_commits;
 128
 129        /*
 130         * blame for a blame_entry with score lower than these thresholds
 131         * is not passed to the parent using move/copy logic.
 132         */
 133        unsigned move_score;
 134        unsigned copy_score;
 135
 136        /* use this file's contents as the final image */
 137        const char *contents_from;
 138
 139        /* flags */
 140        int reverse;
 141        int show_root;
 142        int xdl_opts;
 143        int no_whole_file_rename;
 144        int debug;
 145
 146        /* callbacks */
 147        void(*on_sanity_fail)(struct blame_scoreboard *, int);
 148        void(*found_guilty_entry)(struct blame_entry *, void *);
 149
 150        void *found_guilty_entry_data;
 151};
 152
 153/*
 154 * Origin is refcounted and usually we keep the blob contents to be
 155 * reused.
 156 */
 157static inline struct blame_origin *blame_origin_incref(struct blame_origin *o)
 158{
 159        if (o)
 160                o->refcnt++;
 161        return o;
 162}
 163void blame_origin_decref(struct blame_origin *o);
 164
 165void blame_coalesce(struct blame_scoreboard *sb);
 166void blame_sort_final(struct blame_scoreboard *sb);
 167unsigned blame_entry_score(struct blame_scoreboard *sb, struct blame_entry *e);
 168void assign_blame(struct blame_scoreboard *sb, int opt);
 169const char *blame_nth_line(struct blame_scoreboard *sb, long lno);
 170
 171void init_scoreboard(struct blame_scoreboard *sb);
 172void setup_scoreboard(struct blame_scoreboard *sb,
 173                      const char *path,
 174                      struct blame_origin **orig);
 175
 176struct blame_entry *blame_entry_prepend(struct blame_entry *head,
 177                                        long start, long end,
 178                                        struct blame_origin *o);
 179
 180extern struct blame_origin *get_blame_suspects(struct commit *commit);
 181
 182#endif /* BLAME_H */