df824b22674624c95883a6d58846ebb0a04823d6
   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/*
  17 * One blob in a commit that is being suspected
  18 */
  19struct blame_origin {
  20        int refcnt;
  21        /* Record preceding blame record for this blob */
  22        struct blame_origin *previous;
  23        /* origins are put in a list linked via `next' hanging off the
  24         * corresponding commit's util field in order to make finding
  25         * them fast.  The presence in this chain does not count
  26         * towards the origin's reference count.  It is tempting to
  27         * let it count as long as the commit is pending examination,
  28         * but even under circumstances where the commit will be
  29         * present multiple times in the priority queue of unexamined
  30         * commits, processing the first instance will not leave any
  31         * work requiring the origin data for the second instance.  An
  32         * interspersed commit changing that would have to be
  33         * preexisting with a different ancestry and with the same
  34         * commit date in order to wedge itself between two instances
  35         * of the same commit in the priority queue _and_ produce
  36         * blame entries relevant for it.  While we don't want to let
  37         * us get tripped up by this case, it certainly does not seem
  38         * worth optimizing for.
  39         */
  40        struct blame_origin *next;
  41        struct commit *commit;
  42        /* `suspects' contains blame entries that may be attributed to
  43         * this origin's commit or to parent commits.  When a commit
  44         * is being processed, all suspects will be moved, either by
  45         * assigning them to an origin in a different commit, or by
  46         * shipping them to the scoreboard's ent list because they
  47         * cannot be attributed to a different commit.
  48         */
  49        struct blame_entry *suspects;
  50        mmfile_t file;
  51        struct object_id blob_oid;
  52        unsigned mode;
  53        /* guilty gets set when shipping any suspects to the final
  54         * blame list instead of other commits
  55         */
  56        char guilty;
  57        char path[FLEX_ARRAY];
  58};
  59
  60/*
  61 * Each group of lines is described by a blame_entry; it can be split
  62 * as we pass blame to the parents.  They are arranged in linked lists
  63 * kept as `suspects' of some unprocessed origin, or entered (when the
  64 * blame origin has been finalized) into the scoreboard structure.
  65 * While the scoreboard structure is only sorted at the end of
  66 * processing (according to final image line number), the lists
  67 * attached to an origin are sorted by the target line number.
  68 */
  69struct blame_entry {
  70        struct blame_entry *next;
  71
  72        /* the first line of this group in the final image;
  73         * internally all line numbers are 0 based.
  74         */
  75        int lno;
  76
  77        /* how many lines this group has */
  78        int num_lines;
  79
  80        /* the commit that introduced this group into the final image */
  81        struct blame_origin *suspect;
  82
  83        /* the line number of the first line of this group in the
  84         * suspect's file; internally all line numbers are 0 based.
  85         */
  86        int s_lno;
  87
  88        /* how significant this entry is -- cached to avoid
  89         * scanning the lines over and over.
  90         */
  91        unsigned score;
  92};
  93
  94/*
  95 * The current state of the blame assignment.
  96 */
  97struct blame_scoreboard {
  98        /* the final commit (i.e. where we started digging from) */
  99        struct commit *final;
 100        /* Priority queue for commits with unassigned blame records */
 101        struct prio_queue commits;
 102        struct rev_info *revs;
 103        const char *path;
 104
 105        /*
 106         * The contents in the final image.
 107         * Used by many functions to obtain contents of the nth line,
 108         * indexed with scoreboard.lineno[blame_entry.lno].
 109         */
 110        const char *final_buf;
 111        unsigned long final_buf_size;
 112
 113        /* linked list of blames */
 114        struct blame_entry *ent;
 115
 116        /* look-up a line in the final buffer */
 117        int num_lines;
 118        int *lineno;
 119
 120        /* stats */
 121        int num_read_blob;
 122        int num_get_patch;
 123        int num_commits;
 124
 125        /*
 126         * blame for a blame_entry with score lower than these thresholds
 127         * is not passed to the parent using move/copy logic.
 128         */
 129        unsigned move_score;
 130        unsigned copy_score;
 131
 132        /* use this file's contents as the final image */
 133        const char *contents_from;
 134
 135        /* flags */
 136        int reverse;
 137        int show_root;
 138        int xdl_opts;
 139        int no_whole_file_rename;
 140        int debug;
 141
 142        /* callbacks */
 143        void(*on_sanity_fail)(struct blame_scoreboard *, int);
 144        void(*found_guilty_entry)(struct blame_entry *, void *);
 145
 146        void *found_guilty_entry_data;
 147};
 148
 149/*
 150 * Origin is refcounted and usually we keep the blob contents to be
 151 * reused.
 152 */
 153static inline struct blame_origin *blame_origin_incref(struct blame_origin *o)
 154{
 155        if (o)
 156                o->refcnt++;
 157        return o;
 158}
 159extern void blame_origin_decref(struct blame_origin *o);
 160
 161extern struct blame_origin *get_origin(struct commit *commit, const char *path);
 162
 163extern struct commit *fake_working_tree_commit(struct diff_options *opt, const char *path, const char *contents_from);
 164
 165extern void blame_coalesce(struct blame_scoreboard *sb);
 166extern void blame_sort_final(struct blame_scoreboard *sb);
 167extern unsigned blame_entry_score(struct blame_scoreboard *sb, struct blame_entry *e);
 168extern void assign_blame(struct blame_scoreboard *sb, int opt);
 169extern const char *blame_nth_line(struct blame_scoreboard *sb, long lno);
 170
 171#endif /* BLAME_H */