submodule--helper: use "--" to signal end of clone options
[gitweb.git] / builtin / blame.c
index 21f42b0b62b81b637f1cc9589cd6c0306a93d05e..bda1a787265e6d44d2ec0bec1e4dee5bf8de9c3b 100644 (file)
@@ -6,21 +6,14 @@
  */
 
 #include "cache.h"
-#include "refs.h"
+#include "config.h"
 #include "builtin.h"
-#include "blob.h"
 #include "commit.h"
-#include "tag.h"
-#include "tree-walk.h"
 #include "diff.h"
-#include "diffcore.h"
 #include "revision.h"
 #include "quote.h"
-#include "xdiff-interface.h"
-#include "cache-tree.h"
 #include "string-list.h"
 #include "mailmap.h"
-#include "mergesort.h"
 #include "parse-options.h"
 #include "prio-queue.h"
 #include "utf8.h"
@@ -29,6 +22,7 @@
 #include "line-log.h"
 #include "dir.h"
 #include "progress.h"
+#include "blame.h"
 
 static char blame_usage[] = N_("git blame [<options>] [<rev-opts>] [<rev>] [--] <file>");
 
@@ -56,1513 +50,27 @@ static int show_progress;
 static struct date_mode blame_date_mode = { DATE_ISO8601 };
 static size_t blame_date_width;
 
-static struct string_list mailmap;
+static struct string_list mailmap = STRING_LIST_INIT_NODUP;
 
 #ifndef DEBUG
 #define DEBUG 0
 #endif
 
-/* stats */
-static int num_read_blob;
-static int num_get_patch;
-static int num_commits;
-
-#define PICKAXE_BLAME_MOVE             01
-#define PICKAXE_BLAME_COPY             02
-#define PICKAXE_BLAME_COPY_HARDER      04
-#define PICKAXE_BLAME_COPY_HARDEST     010
-
-/*
- * blame for a blame_entry with score lower than these thresholds
- * is not passed to the parent using move/copy logic.
- */
-static unsigned blame_move_score;
-static unsigned blame_copy_score;
-#define BLAME_DEFAULT_MOVE_SCORE       20
-#define BLAME_DEFAULT_COPY_SCORE       40
-
-/* Remember to update object flag allocation in object.h */
-#define METAINFO_SHOWN         (1u<<12)
-#define MORE_THAN_ONE_PATH     (1u<<13)
-
-/*
- * One blob in a commit that is being suspected
- */
-struct origin {
-       int refcnt;
-       /* Record preceding blame record for this blob */
-       struct origin *previous;
-       /* origins are put in a list linked via `next' hanging off the
-        * corresponding commit's util field in order to make finding
-        * them fast.  The presence in this chain does not count
-        * towards the origin's reference count.  It is tempting to
-        * let it count as long as the commit is pending examination,
-        * but even under circumstances where the commit will be
-        * present multiple times in the priority queue of unexamined
-        * commits, processing the first instance will not leave any
-        * work requiring the origin data for the second instance.  An
-        * interspersed commit changing that would have to be
-        * preexisting with a different ancestry and with the same
-        * commit date in order to wedge itself between two instances
-        * of the same commit in the priority queue _and_ produce
-        * blame entries relevant for it.  While we don't want to let
-        * us get tripped up by this case, it certainly does not seem
-        * worth optimizing for.
-        */
-       struct origin *next;
-       struct commit *commit;
-       /* `suspects' contains blame entries that may be attributed to
-        * this origin's commit or to parent commits.  When a commit
-        * is being processed, all suspects will be moved, either by
-        * assigning them to an origin in a different commit, or by
-        * shipping them to the scoreboard's ent list because they
-        * cannot be attributed to a different commit.
-        */
-       struct blame_entry *suspects;
-       mmfile_t file;
-       unsigned char blob_sha1[20];
-       unsigned mode;
-       /* guilty gets set when shipping any suspects to the final
-        * blame list instead of other commits
-        */
-       char guilty;
-       char path[FLEX_ARRAY];
-};
-
-struct progress_info {
-       struct progress *progress;
-       int blamed_lines;
-};
-
-static int diff_hunks(mmfile_t *file_a, mmfile_t *file_b, long ctxlen,
-                     xdl_emit_hunk_consume_func_t hunk_func, void *cb_data)
-{
-       xpparam_t xpp = {0};
-       xdemitconf_t xecfg = {0};
-       xdemitcb_t ecb = {NULL};
-
-       xpp.flags = xdl_opts;
-       xecfg.ctxlen = ctxlen;
-       xecfg.hunk_func = hunk_func;
-       ecb.priv = cb_data;
-       return xdi_diff(file_a, file_b, &xpp, &xecfg, &ecb);
-}
-
-/*
- * Prepare diff_filespec and convert it using diff textconv API
- * if the textconv driver exists.
- * Return 1 if the conversion succeeds, 0 otherwise.
- */
-int textconv_object(const char *path,
-                   unsigned mode,
-                   const unsigned char *sha1,
-                   int sha1_valid,
-                   char **buf,
-                   unsigned long *buf_size)
-{
-       struct diff_filespec *df;
-       struct userdiff_driver *textconv;
-
-       df = alloc_filespec(path);
-       fill_filespec(df, sha1, sha1_valid, mode);
-       textconv = get_textconv(df);
-       if (!textconv) {
-               free_filespec(df);
-               return 0;
-       }
-
-       *buf_size = fill_textconv(textconv, df, buf);
-       free_filespec(df);
-       return 1;
-}
-
-/*
- * Given an origin, prepare mmfile_t structure to be used by the
- * diff machinery
- */
-static void fill_origin_blob(struct diff_options *opt,
-                            struct origin *o, mmfile_t *file)
-{
-       if (!o->file.ptr) {
-               enum object_type type;
-               unsigned long file_size;
-
-               num_read_blob++;
-               if (DIFF_OPT_TST(opt, ALLOW_TEXTCONV) &&
-                   textconv_object(o->path, o->mode, o->blob_sha1, 1, &file->ptr, &file_size))
-                       ;
-               else
-                       file->ptr = read_sha1_file(o->blob_sha1, &type, &file_size);
-               file->size = file_size;
-
-               if (!file->ptr)
-                       die("Cannot read blob %s for path %s",
-                           sha1_to_hex(o->blob_sha1),
-                           o->path);
-               o->file = *file;
-       }
-       else
-               *file = o->file;
-}
-
-/*
- * Origin is refcounted and usually we keep the blob contents to be
- * reused.
- */
-static inline struct origin *origin_incref(struct origin *o)
-{
-       if (o)
-               o->refcnt++;
-       return o;
-}
-
-static void origin_decref(struct origin *o)
-{
-       if (o && --o->refcnt <= 0) {
-               struct origin *p, *l = NULL;
-               if (o->previous)
-                       origin_decref(o->previous);
-               free(o->file.ptr);
-               /* Should be present exactly once in commit chain */
-               for (p = o->commit->util; p; l = p, p = p->next) {
-                       if (p == o) {
-                               if (l)
-                                       l->next = p->next;
-                               else
-                                       o->commit->util = p->next;
-                               free(o);
-                               return;
-                       }
-               }
-               die("internal error in blame::origin_decref");
-       }
-}
-
-static void drop_origin_blob(struct origin *o)
-{
-       if (o->file.ptr) {
-               free(o->file.ptr);
-               o->file.ptr = NULL;
-       }
-}
-
-/*
- * Each group of lines is described by a blame_entry; it can be split
- * as we pass blame to the parents.  They are arranged in linked lists
- * kept as `suspects' of some unprocessed origin, or entered (when the
- * blame origin has been finalized) into the scoreboard structure.
- * While the scoreboard structure is only sorted at the end of
- * processing (according to final image line number), the lists
- * attached to an origin are sorted by the target line number.
- */
-struct blame_entry {
-       struct blame_entry *next;
-
-       /* the first line of this group in the final image;
-        * internally all line numbers are 0 based.
-        */
-       int lno;
-
-       /* how many lines this group has */
-       int num_lines;
-
-       /* the commit that introduced this group into the final image */
-       struct origin *suspect;
-
-       /* the line number of the first line of this group in the
-        * suspect's file; internally all line numbers are 0 based.
-        */
-       int s_lno;
-
-       /* how significant this entry is -- cached to avoid
-        * scanning the lines over and over.
-        */
-       unsigned score;
-};
-
-/*
- * Any merge of blames happens on lists of blames that arrived via
- * different parents in a single suspect.  In this case, we want to
- * sort according to the suspect line numbers as opposed to the final
- * image line numbers.  The function body is somewhat longish because
- * it avoids unnecessary writes.
- */
-
-static struct blame_entry *blame_merge(struct blame_entry *list1,
-                                      struct blame_entry *list2)
-{
-       struct blame_entry *p1 = list1, *p2 = list2,
-               **tail = &list1;
-
-       if (!p1)
-               return p2;
-       if (!p2)
-               return p1;
-
-       if (p1->s_lno <= p2->s_lno) {
-               do {
-                       tail = &p1->next;
-                       if ((p1 = *tail) == NULL) {
-                               *tail = p2;
-                               return list1;
-                       }
-               } while (p1->s_lno <= p2->s_lno);
-       }
-       for (;;) {
-               *tail = p2;
-               do {
-                       tail = &p2->next;
-                       if ((p2 = *tail) == NULL)  {
-                               *tail = p1;
-                               return list1;
-                       }
-               } while (p1->s_lno > p2->s_lno);
-               *tail = p1;
-               do {
-                       tail = &p1->next;
-                       if ((p1 = *tail) == NULL) {
-                               *tail = p2;
-                               return list1;
-                       }
-               } while (p1->s_lno <= p2->s_lno);
-       }
-}
-
-static void *get_next_blame(const void *p)
-{
-       return ((struct blame_entry *)p)->next;
-}
-
-static void set_next_blame(void *p1, void *p2)
-{
-       ((struct blame_entry *)p1)->next = p2;
-}
-
-/*
- * Final image line numbers are all different, so we don't need a
- * three-way comparison here.
- */
-
-static int compare_blame_final(const void *p1, const void *p2)
-{
-       return ((struct blame_entry *)p1)->lno > ((struct blame_entry *)p2)->lno
-               ? 1 : -1;
-}
-
-static int compare_blame_suspect(const void *p1, const void *p2)
-{
-       const struct blame_entry *s1 = p1, *s2 = p2;
-       /*
-        * to allow for collating suspects, we sort according to the
-        * respective pointer value as the primary sorting criterion.
-        * The actual relation is pretty unimportant as long as it
-        * establishes a total order.  Comparing as integers gives us
-        * that.
-        */
-       if (s1->suspect != s2->suspect)
-               return (intptr_t)s1->suspect > (intptr_t)s2->suspect ? 1 : -1;
-       if (s1->s_lno == s2->s_lno)
-               return 0;
-       return s1->s_lno > s2->s_lno ? 1 : -1;
-}
-
-static struct blame_entry *blame_sort(struct blame_entry *head,
-                                     int (*compare_fn)(const void *, const void *))
-{
-       return llist_mergesort (head, get_next_blame, set_next_blame, compare_fn);
-}
-
-static int compare_commits_by_reverse_commit_date(const void *a,
-                                                 const void *b,
-                                                 void *c)
-{
-       return -compare_commits_by_commit_date(a, b, c);
-}
-
-/*
- * The current state of the blame assignment.
- */
-struct scoreboard {
-       /* the final commit (i.e. where we started digging from) */
-       struct commit *final;
-       /* Priority queue for commits with unassigned blame records */
-       struct prio_queue commits;
-       struct rev_info *revs;
-       const char *path;
-
-       /*
-        * The contents in the final image.
-        * Used by many functions to obtain contents of the nth line,
-        * indexed with scoreboard.lineno[blame_entry.lno].
-        */
-       const char *final_buf;
-       unsigned long final_buf_size;
-
-       /* linked list of blames */
-       struct blame_entry *ent;
-
-       /* look-up a line in the final buffer */
-       int num_lines;
-       int *lineno;
-};
-
-static void sanity_check_refcnt(struct scoreboard *);
-
-/*
- * If two blame entries that are next to each other came from
- * contiguous lines in the same origin (i.e. <commit, path> pair),
- * merge them together.
- */
-static void coalesce(struct scoreboard *sb)
-{
-       struct blame_entry *ent, *next;
-
-       for (ent = sb->ent; ent && (next = ent->next); ent = next) {
-               if (ent->suspect == next->suspect &&
-                   ent->s_lno + ent->num_lines == next->s_lno) {
-                       ent->num_lines += next->num_lines;
-                       ent->next = next->next;
-                       origin_decref(next->suspect);
-                       free(next);
-                       ent->score = 0;
-                       next = ent; /* again */
-               }
-       }
-
-       if (DEBUG) /* sanity */
-               sanity_check_refcnt(sb);
-}
-
-/*
- * Merge the given sorted list of blames into a preexisting origin.
- * If there were no previous blames to that commit, it is entered into
- * the commit priority queue of the score board.
- */
-
-static void queue_blames(struct scoreboard *sb, struct origin *porigin,
-                        struct blame_entry *sorted)
-{
-       if (porigin->suspects)
-               porigin->suspects = blame_merge(porigin->suspects, sorted);
-       else {
-               struct origin *o;
-               for (o = porigin->commit->util; o; o = o->next) {
-                       if (o->suspects) {
-                               porigin->suspects = sorted;
-                               return;
-                       }
-               }
-               porigin->suspects = sorted;
-               prio_queue_put(&sb->commits, porigin->commit);
-       }
-}
-
-/*
- * Given a commit and a path in it, create a new origin structure.
- * The callers that add blame to the scoreboard should use
- * get_origin() to obtain shared, refcounted copy instead of calling
- * this function directly.
- */
-static struct origin *make_origin(struct commit *commit, const char *path)
-{
-       struct origin *o;
-       FLEX_ALLOC_STR(o, path, path);
-       o->commit = commit;
-       o->refcnt = 1;
-       o->next = commit->util;
-       commit->util = o;
-       return o;
-}
-
-/*
- * Locate an existing origin or create a new one.
- * This moves the origin to front position in the commit util list.
- */
-static struct origin *get_origin(struct scoreboard *sb,
-                                struct commit *commit,
-                                const char *path)
-{
-       struct origin *o, *l;
-
-       for (o = commit->util, l = NULL; o; l = o, o = o->next) {
-               if (!strcmp(o->path, path)) {
-                       /* bump to front */
-                       if (l) {
-                               l->next = o->next;
-                               o->next = commit->util;
-                               commit->util = o;
-                       }
-                       return origin_incref(o);
-               }
-       }
-       return make_origin(commit, path);
-}
-
-/*
- * Fill the blob_sha1 field of an origin if it hasn't, so that later
- * call to fill_origin_blob() can use it to locate the data.  blob_sha1
- * for an origin is also used to pass the blame for the entire file to
- * the parent to detect the case where a child's blob is identical to
- * that of its parent's.
- *
- * This also fills origin->mode for corresponding tree path.
- */
-static int fill_blob_sha1_and_mode(struct origin *origin)
-{
-       if (!is_null_sha1(origin->blob_sha1))
-               return 0;
-       if (get_tree_entry(origin->commit->object.oid.hash,
-                          origin->path,
-                          origin->blob_sha1, &origin->mode))
-               goto error_out;
-       if (sha1_object_info(origin->blob_sha1, NULL) != OBJ_BLOB)
-               goto error_out;
-       return 0;
- error_out:
-       hashclr(origin->blob_sha1);
-       origin->mode = S_IFINVALID;
-       return -1;
-}
-
-/*
- * We have an origin -- check if the same path exists in the
- * parent and return an origin structure to represent it.
- */
-static struct origin *find_origin(struct scoreboard *sb,
-                                 struct commit *parent,
-                                 struct origin *origin)
-{
-       struct origin *porigin;
-       struct diff_options diff_opts;
-       const char *paths[2];
-
-       /* First check any existing origins */
-       for (porigin = parent->util; porigin; porigin = porigin->next)
-               if (!strcmp(porigin->path, origin->path)) {
-                       /*
-                        * The same path between origin and its parent
-                        * without renaming -- the most common case.
-                        */
-                       return origin_incref (porigin);
-               }
-
-       /* See if the origin->path is different between parent
-        * and origin first.  Most of the time they are the
-        * same and diff-tree is fairly efficient about this.
-        */
-       diff_setup(&diff_opts);
-       DIFF_OPT_SET(&diff_opts, RECURSIVE);
-       diff_opts.detect_rename = 0;
-       diff_opts.output_format = DIFF_FORMAT_NO_OUTPUT;
-       paths[0] = origin->path;
-       paths[1] = NULL;
-
-       parse_pathspec(&diff_opts.pathspec,
-                      PATHSPEC_ALL_MAGIC & ~PATHSPEC_LITERAL,
-                      PATHSPEC_LITERAL_PATH, "", paths);
-       diff_setup_done(&diff_opts);
-
-       if (is_null_oid(&origin->commit->object.oid))
-               do_diff_cache(parent->tree->object.oid.hash, &diff_opts);
-       else
-               diff_tree_sha1(parent->tree->object.oid.hash,
-                              origin->commit->tree->object.oid.hash,
-                              "", &diff_opts);
-       diffcore_std(&diff_opts);
-
-       if (!diff_queued_diff.nr) {
-               /* The path is the same as parent */
-               porigin = get_origin(sb, parent, origin->path);
-               hashcpy(porigin->blob_sha1, origin->blob_sha1);
-               porigin->mode = origin->mode;
-       } else {
-               /*
-                * Since origin->path is a pathspec, if the parent
-                * commit had it as a directory, we will see a whole
-                * bunch of deletion of files in the directory that we
-                * do not care about.
-                */
-               int i;
-               struct diff_filepair *p = NULL;
-               for (i = 0; i < diff_queued_diff.nr; i++) {
-                       const char *name;
-                       p = diff_queued_diff.queue[i];
-                       name = p->one->path ? p->one->path : p->two->path;
-                       if (!strcmp(name, origin->path))
-                               break;
-               }
-               if (!p)
-                       die("internal error in blame::find_origin");
-               switch (p->status) {
-               default:
-                       die("internal error in blame::find_origin (%c)",
-                           p->status);
-               case 'M':
-                       porigin = get_origin(sb, parent, origin->path);
-                       hashcpy(porigin->blob_sha1, p->one->sha1);
-                       porigin->mode = p->one->mode;
-                       break;
-               case 'A':
-               case 'T':
-                       /* Did not exist in parent, or type changed */
-                       break;
-               }
-       }
-       diff_flush(&diff_opts);
-       free_pathspec(&diff_opts.pathspec);
-       return porigin;
-}
-
-/*
- * We have an origin -- find the path that corresponds to it in its
- * parent and return an origin structure to represent it.
- */
-static struct origin *find_rename(struct scoreboard *sb,
-                                 struct commit *parent,
-                                 struct origin *origin)
-{
-       struct origin *porigin = NULL;
-       struct diff_options diff_opts;
-       int i;
-
-       diff_setup(&diff_opts);
-       DIFF_OPT_SET(&diff_opts, RECURSIVE);
-       diff_opts.detect_rename = DIFF_DETECT_RENAME;
-       diff_opts.output_format = DIFF_FORMAT_NO_OUTPUT;
-       diff_opts.single_follow = origin->path;
-       diff_setup_done(&diff_opts);
-
-       if (is_null_oid(&origin->commit->object.oid))
-               do_diff_cache(parent->tree->object.oid.hash, &diff_opts);
-       else
-               diff_tree_sha1(parent->tree->object.oid.hash,
-                              origin->commit->tree->object.oid.hash,
-                              "", &diff_opts);
-       diffcore_std(&diff_opts);
-
-       for (i = 0; i < diff_queued_diff.nr; i++) {
-               struct diff_filepair *p = diff_queued_diff.queue[i];
-               if ((p->status == 'R' || p->status == 'C') &&
-                   !strcmp(p->two->path, origin->path)) {
-                       porigin = get_origin(sb, parent, p->one->path);
-                       hashcpy(porigin->blob_sha1, p->one->sha1);
-                       porigin->mode = p->one->mode;
-                       break;
-               }
-       }
-       diff_flush(&diff_opts);
-       free_pathspec(&diff_opts.pathspec);
-       return porigin;
-}
-
-/*
- * Append a new blame entry to a given output queue.
- */
-static void add_blame_entry(struct blame_entry ***queue, struct blame_entry *e)
-{
-       origin_incref(e->suspect);
-
-       e->next = **queue;
-       **queue = e;
-       *queue = &e->next;
-}
-
-/*
- * src typically is on-stack; we want to copy the information in it to
- * a malloced blame_entry that gets added to the given queue.  The
- * origin of dst loses a refcnt.
- */
-static void dup_entry(struct blame_entry ***queue,
-                     struct blame_entry *dst, struct blame_entry *src)
-{
-       origin_incref(src->suspect);
-       origin_decref(dst->suspect);
-       memcpy(dst, src, sizeof(*src));
-       dst->next = **queue;
-       **queue = dst;
-       *queue = &dst->next;
-}
-
-static const char *nth_line(struct scoreboard *sb, long lno)
-{
-       return sb->final_buf + sb->lineno[lno];
-}
-
-static const char *nth_line_cb(void *data, long lno)
-{
-       return nth_line((struct scoreboard *)data, lno);
-}
-
-/*
- * It is known that lines between tlno to same came from parent, and e
- * has an overlap with that range.  it also is known that parent's
- * line plno corresponds to e's line tlno.
- *
- *                <---- e ----->
- *                   <------>
- *                   <------------>
- *             <------------>
- *             <------------------>
- *
- * Split e into potentially three parts; before this chunk, the chunk
- * to be blamed for the parent, and after that portion.
- */
-static void split_overlap(struct blame_entry *split,
-                         struct blame_entry *e,
-                         int tlno, int plno, int same,
-                         struct origin *parent)
-{
-       int chunk_end_lno;
-       memset(split, 0, sizeof(struct blame_entry [3]));
-
-       if (e->s_lno < tlno) {
-               /* there is a pre-chunk part not blamed on parent */
-               split[0].suspect = origin_incref(e->suspect);
-               split[0].lno = e->lno;
-               split[0].s_lno = e->s_lno;
-               split[0].num_lines = tlno - e->s_lno;
-               split[1].lno = e->lno + tlno - e->s_lno;
-               split[1].s_lno = plno;
-       }
-       else {
-               split[1].lno = e->lno;
-               split[1].s_lno = plno + (e->s_lno - tlno);
-       }
-
-       if (same < e->s_lno + e->num_lines) {
-               /* there is a post-chunk part not blamed on parent */
-               split[2].suspect = origin_incref(e->suspect);
-               split[2].lno = e->lno + (same - e->s_lno);
-               split[2].s_lno = e->s_lno + (same - e->s_lno);
-               split[2].num_lines = e->s_lno + e->num_lines - same;
-               chunk_end_lno = split[2].lno;
-       }
-       else
-               chunk_end_lno = e->lno + e->num_lines;
-       split[1].num_lines = chunk_end_lno - split[1].lno;
-
-       /*
-        * if it turns out there is nothing to blame the parent for,
-        * forget about the splitting.  !split[1].suspect signals this.
-        */
-       if (split[1].num_lines < 1)
-               return;
-       split[1].suspect = origin_incref(parent);
-}
-
-/*
- * split_overlap() divided an existing blame e into up to three parts
- * in split.  Any assigned blame is moved to queue to
- * reflect the split.
- */
-static void split_blame(struct blame_entry ***blamed,
-                       struct blame_entry ***unblamed,
-                       struct blame_entry *split,
-                       struct blame_entry *e)
-{
-       struct blame_entry *new_entry;
-
-       if (split[0].suspect && split[2].suspect) {
-               /* The first part (reuse storage for the existing entry e) */
-               dup_entry(unblamed, e, &split[0]);
-
-               /* The last part -- me */
-               new_entry = xmalloc(sizeof(*new_entry));
-               memcpy(new_entry, &(split[2]), sizeof(struct blame_entry));
-               add_blame_entry(unblamed, new_entry);
-
-               /* ... and the middle part -- parent */
-               new_entry = xmalloc(sizeof(*new_entry));
-               memcpy(new_entry, &(split[1]), sizeof(struct blame_entry));
-               add_blame_entry(blamed, new_entry);
-       }
-       else if (!split[0].suspect && !split[2].suspect)
-               /*
-                * The parent covers the entire area; reuse storage for
-                * e and replace it with the parent.
-                */
-               dup_entry(blamed, e, &split[1]);
-       else if (split[0].suspect) {
-               /* me and then parent */
-               dup_entry(unblamed, e, &split[0]);
-
-               new_entry = xmalloc(sizeof(*new_entry));
-               memcpy(new_entry, &(split[1]), sizeof(struct blame_entry));
-               add_blame_entry(blamed, new_entry);
-       }
-       else {
-               /* parent and then me */
-               dup_entry(blamed, e, &split[1]);
-
-               new_entry = xmalloc(sizeof(*new_entry));
-               memcpy(new_entry, &(split[2]), sizeof(struct blame_entry));
-               add_blame_entry(unblamed, new_entry);
-       }
-}
-
-/*
- * After splitting the blame, the origins used by the
- * on-stack blame_entry should lose one refcnt each.
- */
-static void decref_split(struct blame_entry *split)
-{
-       int i;
-
-       for (i = 0; i < 3; i++)
-               origin_decref(split[i].suspect);
-}
-
-/*
- * reverse_blame reverses the list given in head, appending tail.
- * That allows us to build lists in reverse order, then reverse them
- * afterwards.  This can be faster than building the list in proper
- * order right away.  The reason is that building in proper order
- * requires writing a link in the _previous_ element, while building
- * in reverse order just requires placing the list head into the
- * _current_ element.
- */
-
-static struct blame_entry *reverse_blame(struct blame_entry *head,
-                                        struct blame_entry *tail)
-{
-       while (head) {
-               struct blame_entry *next = head->next;
-               head->next = tail;
-               tail = head;
-               head = next;
-       }
-       return tail;
-}
-
-/*
- * Process one hunk from the patch between the current suspect for
- * blame_entry e and its parent.  This first blames any unfinished
- * entries before the chunk (which is where target and parent start
- * differing) on the parent, and then splits blame entries at the
- * start and at the end of the difference region.  Since use of -M and
- * -C options may lead to overlapping/duplicate source line number
- * ranges, all we can rely on from sorting/merging is the order of the
- * first suspect line number.
- */
-static void blame_chunk(struct blame_entry ***dstq, struct blame_entry ***srcq,
-                       int tlno, int offset, int same,
-                       struct origin *parent)
-{
-       struct blame_entry *e = **srcq;
-       struct blame_entry *samep = NULL, *diffp = NULL;
-
-       while (e && e->s_lno < tlno) {
-               struct blame_entry *next = e->next;
-               /*
-                * current record starts before differing portion.  If
-                * it reaches into it, we need to split it up and
-                * examine the second part separately.
-                */
-               if (e->s_lno + e->num_lines > tlno) {
-                       /* Move second half to a new record */
-                       int len = tlno - e->s_lno;
-                       struct blame_entry *n = xcalloc(1, sizeof (struct blame_entry));
-                       n->suspect = e->suspect;
-                       n->lno = e->lno + len;
-                       n->s_lno = e->s_lno + len;
-                       n->num_lines = e->num_lines - len;
-                       e->num_lines = len;
-                       e->score = 0;
-                       /* Push new record to diffp */
-                       n->next = diffp;
-                       diffp = n;
-               } else
-                       origin_decref(e->suspect);
-               /* Pass blame for everything before the differing
-                * chunk to the parent */
-               e->suspect = origin_incref(parent);
-               e->s_lno += offset;
-               e->next = samep;
-               samep = e;
-               e = next;
-       }
-       /*
-        * As we don't know how much of a common stretch after this
-        * diff will occur, the currently blamed parts are all that we
-        * can assign to the parent for now.
-        */
-
-       if (samep) {
-               **dstq = reverse_blame(samep, **dstq);
-               *dstq = &samep->next;
-       }
-       /*
-        * Prepend the split off portions: everything after e starts
-        * after the blameable portion.
-        */
-       e = reverse_blame(diffp, e);
-
-       /*
-        * Now retain records on the target while parts are different
-        * from the parent.
-        */
-       samep = NULL;
-       diffp = NULL;
-       while (e && e->s_lno < same) {
-               struct blame_entry *next = e->next;
-
-               /*
-                * If current record extends into sameness, need to split.
-                */
-               if (e->s_lno + e->num_lines > same) {
-                       /*
-                        * Move second half to a new record to be
-                        * processed by later chunks
-                        */
-                       int len = same - e->s_lno;
-                       struct blame_entry *n = xcalloc(1, sizeof (struct blame_entry));
-                       n->suspect = origin_incref(e->suspect);
-                       n->lno = e->lno + len;
-                       n->s_lno = e->s_lno + len;
-                       n->num_lines = e->num_lines - len;
-                       e->num_lines = len;
-                       e->score = 0;
-                       /* Push new record to samep */
-                       n->next = samep;
-                       samep = n;
-               }
-               e->next = diffp;
-               diffp = e;
-               e = next;
-       }
-       **srcq = reverse_blame(diffp, reverse_blame(samep, e));
-       /* Move across elements that are in the unblamable portion */
-       if (diffp)
-               *srcq = &diffp->next;
-}
-
-struct blame_chunk_cb_data {
-       struct origin *parent;
-       long offset;
-       struct blame_entry **dstq;
-       struct blame_entry **srcq;
-};
-
-/* diff chunks are from parent to target */
-static int blame_chunk_cb(long start_a, long count_a,
-                         long start_b, long count_b, void *data)
-{
-       struct blame_chunk_cb_data *d = data;
-       if (start_a - start_b != d->offset)
-               die("internal error in blame::blame_chunk_cb");
-       blame_chunk(&d->dstq, &d->srcq, start_b, start_a - start_b,
-                   start_b + count_b, d->parent);
-       d->offset = start_a + count_a - (start_b + count_b);
-       return 0;
-}
-
-/*
- * We are looking at the origin 'target' and aiming to pass blame
- * for the lines it is suspected to its parent.  Run diff to find
- * which lines came from parent and pass blame for them.
- */
-static void pass_blame_to_parent(struct scoreboard *sb,
-                                struct origin *target,
-                                struct origin *parent)
-{
-       mmfile_t file_p, file_o;
-       struct blame_chunk_cb_data d;
-       struct blame_entry *newdest = NULL;
-
-       if (!target->suspects)
-               return; /* nothing remains for this target */
-
-       d.parent = parent;
-       d.offset = 0;
-       d.dstq = &newdest; d.srcq = &target->suspects;
-
-       fill_origin_blob(&sb->revs->diffopt, parent, &file_p);
-       fill_origin_blob(&sb->revs->diffopt, target, &file_o);
-       num_get_patch++;
-
-       if (diff_hunks(&file_p, &file_o, 0, blame_chunk_cb, &d))
-               die("unable to generate diff (%s -> %s)",
-                   oid_to_hex(&parent->commit->object.oid),
-                   oid_to_hex(&target->commit->object.oid));
-       /* The rest are the same as the parent */
-       blame_chunk(&d.dstq, &d.srcq, INT_MAX, d.offset, INT_MAX, parent);
-       *d.dstq = NULL;
-       queue_blames(sb, parent, newdest);
-
-       return;
-}
-
-/*
- * The lines in blame_entry after splitting blames many times can become
- * very small and trivial, and at some point it becomes pointless to
- * blame the parents.  E.g. "\t\t}\n\t}\n\n" appears everywhere in any
- * ordinary C program, and it is not worth to say it was copied from
- * totally unrelated file in the parent.
- *
- * Compute how trivial the lines in the blame_entry are.
- */
-static unsigned ent_score(struct scoreboard *sb, struct blame_entry *e)
-{
-       unsigned score;
-       const char *cp, *ep;
-
-       if (e->score)
-               return e->score;
-
-       score = 1;
-       cp = nth_line(sb, e->lno);
-       ep = nth_line(sb, e->lno + e->num_lines);
-       while (cp < ep) {
-               unsigned ch = *((unsigned char *)cp);
-               if (isalnum(ch))
-                       score++;
-               cp++;
-       }
-       e->score = score;
-       return score;
-}
-
-/*
- * best_so_far[] and this[] are both a split of an existing blame_entry
- * that passes blame to the parent.  Maintain best_so_far the best split
- * so far, by comparing this and best_so_far and copying this into
- * bst_so_far as needed.
- */
-static void copy_split_if_better(struct scoreboard *sb,
-                                struct blame_entry *best_so_far,
-                                struct blame_entry *this)
-{
-       int i;
-
-       if (!this[1].suspect)
-               return;
-       if (best_so_far[1].suspect) {
-               if (ent_score(sb, &this[1]) < ent_score(sb, &best_so_far[1]))
-                       return;
-       }
-
-       for (i = 0; i < 3; i++)
-               origin_incref(this[i].suspect);
-       decref_split(best_so_far);
-       memcpy(best_so_far, this, sizeof(struct blame_entry [3]));
-}
-
-/*
- * We are looking at a part of the final image represented by
- * ent (tlno and same are offset by ent->s_lno).
- * tlno is where we are looking at in the final image.
- * up to (but not including) same match preimage.
- * plno is where we are looking at in the preimage.
- *
- * <-------------- final image ---------------------->
- *       <------ent------>
- *         ^tlno ^same
- *    <---------preimage----->
- *         ^plno
- *
- * All line numbers are 0-based.
- */
-static void handle_split(struct scoreboard *sb,
-                        struct blame_entry *ent,
-                        int tlno, int plno, int same,
-                        struct origin *parent,
-                        struct blame_entry *split)
-{
-       if (ent->num_lines <= tlno)
-               return;
-       if (tlno < same) {
-               struct blame_entry this[3];
-               tlno += ent->s_lno;
-               same += ent->s_lno;
-               split_overlap(this, ent, tlno, plno, same, parent);
-               copy_split_if_better(sb, split, this);
-               decref_split(this);
-       }
-}
-
-struct handle_split_cb_data {
-       struct scoreboard *sb;
-       struct blame_entry *ent;
-       struct origin *parent;
-       struct blame_entry *split;
-       long plno;
-       long tlno;
-};
-
-static int handle_split_cb(long start_a, long count_a,
-                          long start_b, long count_b, void *data)
-{
-       struct handle_split_cb_data *d = data;
-       handle_split(d->sb, d->ent, d->tlno, d->plno, start_b, d->parent,
-                    d->split);
-       d->plno = start_a + count_a;
-       d->tlno = start_b + count_b;
-       return 0;
-}
-
-/*
- * Find the lines from parent that are the same as ent so that
- * we can pass blames to it.  file_p has the blob contents for
- * the parent.
- */
-static void find_copy_in_blob(struct scoreboard *sb,
-                             struct blame_entry *ent,
-                             struct origin *parent,
-                             struct blame_entry *split,
-                             mmfile_t *file_p)
-{
-       const char *cp;
-       mmfile_t file_o;
-       struct handle_split_cb_data d;
-
-       memset(&d, 0, sizeof(d));
-       d.sb = sb; d.ent = ent; d.parent = parent; d.split = split;
-       /*
-        * Prepare mmfile that contains only the lines in ent.
-        */
-       cp = nth_line(sb, ent->lno);
-       file_o.ptr = (char *) cp;
-       file_o.size = nth_line(sb, ent->lno + ent->num_lines) - cp;
-
-       /*
-        * file_o is a part of final image we are annotating.
-        * file_p partially may match that image.
-        */
-       memset(split, 0, sizeof(struct blame_entry [3]));
-       if (diff_hunks(file_p, &file_o, 1, handle_split_cb, &d))
-               die("unable to generate diff (%s)",
-                   oid_to_hex(&parent->commit->object.oid));
-       /* remainder, if any, all match the preimage */
-       handle_split(sb, ent, d.tlno, d.plno, ent->num_lines, parent, split);
-}
-
-/* Move all blame entries from list *source that have a score smaller
- * than score_min to the front of list *small.
- * Returns a pointer to the link pointing to the old head of the small list.
- */
-
-static struct blame_entry **filter_small(struct scoreboard *sb,
-                                        struct blame_entry **small,
-                                        struct blame_entry **source,
-                                        unsigned score_min)
-{
-       struct blame_entry *p = *source;
-       struct blame_entry *oldsmall = *small;
-       while (p) {
-               if (ent_score(sb, p) <= score_min) {
-                       *small = p;
-                       small = &p->next;
-                       p = *small;
-               } else {
-                       *source = p;
-                       source = &p->next;
-                       p = *source;
-               }
-       }
-       *small = oldsmall;
-       *source = NULL;
-       return small;
-}
-
-/*
- * See if lines currently target is suspected for can be attributed to
- * parent.
- */
-static void find_move_in_parent(struct scoreboard *sb,
-                               struct blame_entry ***blamed,
-                               struct blame_entry **toosmall,
-                               struct origin *target,
-                               struct origin *parent)
-{
-       struct blame_entry *e, split[3];
-       struct blame_entry *unblamed = target->suspects;
-       struct blame_entry *leftover = NULL;
-       mmfile_t file_p;
-
-       if (!unblamed)
-               return; /* nothing remains for this target */
-
-       fill_origin_blob(&sb->revs->diffopt, parent, &file_p);
-       if (!file_p.ptr)
-               return;
+static unsigned blame_move_score;
+static unsigned blame_copy_score;
 
-       /* At each iteration, unblamed has a NULL-terminated list of
-        * entries that have not yet been tested for blame.  leftover
-        * contains the reversed list of entries that have been tested
-        * without being assignable to the parent.
-        */
-       do {
-               struct blame_entry **unblamedtail = &unblamed;
-               struct blame_entry *next;
-               for (e = unblamed; e; e = next) {
-                       next = e->next;
-                       find_copy_in_blob(sb, e, parent, split, &file_p);
-                       if (split[1].suspect &&
-                           blame_move_score < ent_score(sb, &split[1])) {
-                               split_blame(blamed, &unblamedtail, split, e);
-                       } else {
-                               e->next = leftover;
-                               leftover = e;
-                       }
-                       decref_split(split);
-               }
-               *unblamedtail = NULL;
-               toosmall = filter_small(sb, toosmall, &unblamed, blame_move_score);
-       } while (unblamed);
-       target->suspects = reverse_blame(leftover, NULL);
-}
+/* Remember to update object flag allocation in object.h */
+#define METAINFO_SHOWN         (1u<<12)
+#define MORE_THAN_ONE_PATH     (1u<<13)
 
-struct blame_list {
-       struct blame_entry *ent;
-       struct blame_entry split[3];
+struct progress_info {
+       struct progress *progress;
+       int blamed_lines;
 };
 
-/*
- * Count the number of entries the target is suspected for,
- * and prepare a list of entry and the best split.
- */
-static struct blame_list *setup_blame_list(struct blame_entry *unblamed,
-                                          int *num_ents_p)
-{
-       struct blame_entry *e;
-       int num_ents, i;
-       struct blame_list *blame_list = NULL;
-
-       for (e = unblamed, num_ents = 0; e; e = e->next)
-               num_ents++;
-       if (num_ents) {
-               blame_list = xcalloc(num_ents, sizeof(struct blame_list));
-               for (e = unblamed, i = 0; e; e = e->next)
-                       blame_list[i++].ent = e;
-       }
-       *num_ents_p = num_ents;
-       return blame_list;
-}
-
-/*
- * For lines target is suspected for, see if we can find code movement
- * across file boundary from the parent commit.  porigin is the path
- * in the parent we already tried.
- */
-static void find_copy_in_parent(struct scoreboard *sb,
-                               struct blame_entry ***blamed,
-                               struct blame_entry **toosmall,
-                               struct origin *target,
-                               struct commit *parent,
-                               struct origin *porigin,
-                               int opt)
-{
-       struct diff_options diff_opts;
-       int i, j;
-       struct blame_list *blame_list;
-       int num_ents;
-       struct blame_entry *unblamed = target->suspects;
-       struct blame_entry *leftover = NULL;
-
-       if (!unblamed)
-               return; /* nothing remains for this target */
-
-       diff_setup(&diff_opts);
-       DIFF_OPT_SET(&diff_opts, RECURSIVE);
-       diff_opts.output_format = DIFF_FORMAT_NO_OUTPUT;
-
-       diff_setup_done(&diff_opts);
-
-       /* Try "find copies harder" on new path if requested;
-        * we do not want to use diffcore_rename() actually to
-        * match things up; find_copies_harder is set only to
-        * force diff_tree_sha1() to feed all filepairs to diff_queue,
-        * and this code needs to be after diff_setup_done(), which
-        * usually makes find-copies-harder imply copy detection.
-        */
-       if ((opt & PICKAXE_BLAME_COPY_HARDEST)
-           || ((opt & PICKAXE_BLAME_COPY_HARDER)
-               && (!porigin || strcmp(target->path, porigin->path))))
-               DIFF_OPT_SET(&diff_opts, FIND_COPIES_HARDER);
-
-       if (is_null_oid(&target->commit->object.oid))
-               do_diff_cache(parent->tree->object.oid.hash, &diff_opts);
-       else
-               diff_tree_sha1(parent->tree->object.oid.hash,
-                              target->commit->tree->object.oid.hash,
-                              "", &diff_opts);
-
-       if (!DIFF_OPT_TST(&diff_opts, FIND_COPIES_HARDER))
-               diffcore_std(&diff_opts);
-
-       do {
-               struct blame_entry **unblamedtail = &unblamed;
-               blame_list = setup_blame_list(unblamed, &num_ents);
-
-               for (i = 0; i < diff_queued_diff.nr; i++) {
-                       struct diff_filepair *p = diff_queued_diff.queue[i];
-                       struct origin *norigin;
-                       mmfile_t file_p;
-                       struct blame_entry this[3];
-
-                       if (!DIFF_FILE_VALID(p->one))
-                               continue; /* does not exist in parent */
-                       if (S_ISGITLINK(p->one->mode))
-                               continue; /* ignore git links */
-                       if (porigin && !strcmp(p->one->path, porigin->path))
-                               /* find_move already dealt with this path */
-                               continue;
-
-                       norigin = get_origin(sb, parent, p->one->path);
-                       hashcpy(norigin->blob_sha1, p->one->sha1);
-                       norigin->mode = p->one->mode;
-                       fill_origin_blob(&sb->revs->diffopt, norigin, &file_p);
-                       if (!file_p.ptr)
-                               continue;
-
-                       for (j = 0; j < num_ents; j++) {
-                               find_copy_in_blob(sb, blame_list[j].ent,
-                                                 norigin, this, &file_p);
-                               copy_split_if_better(sb, blame_list[j].split,
-                                                    this);
-                               decref_split(this);
-                       }
-                       origin_decref(norigin);
-               }
-
-               for (j = 0; j < num_ents; j++) {
-                       struct blame_entry *split = blame_list[j].split;
-                       if (split[1].suspect &&
-                           blame_copy_score < ent_score(sb, &split[1])) {
-                               split_blame(blamed, &unblamedtail, split,
-                                           blame_list[j].ent);
-                       } else {
-                               blame_list[j].ent->next = leftover;
-                               leftover = blame_list[j].ent;
-                       }
-                       decref_split(split);
-               }
-               free(blame_list);
-               *unblamedtail = NULL;
-               toosmall = filter_small(sb, toosmall, &unblamed, blame_copy_score);
-       } while (unblamed);
-       target->suspects = reverse_blame(leftover, NULL);
-       diff_flush(&diff_opts);
-       free_pathspec(&diff_opts.pathspec);
-}
-
-/*
- * The blobs of origin and porigin exactly match, so everything
- * origin is suspected for can be blamed on the parent.
- */
-static void pass_whole_blame(struct scoreboard *sb,
-                            struct origin *origin, struct origin *porigin)
-{
-       struct blame_entry *e, *suspects;
-
-       if (!porigin->file.ptr && origin->file.ptr) {
-               /* Steal its file */
-               porigin->file = origin->file;
-               origin->file.ptr = NULL;
-       }
-       suspects = origin->suspects;
-       origin->suspects = NULL;
-       for (e = suspects; e; e = e->next) {
-               origin_incref(porigin);
-               origin_decref(e->suspect);
-               e->suspect = porigin;
-       }
-       queue_blames(sb, porigin, suspects);
-}
-
-/*
- * We pass blame from the current commit to its parents.  We keep saying
- * "parent" (and "porigin"), but what we mean is to find scapegoat to
- * exonerate ourselves.
- */
-static struct commit_list *first_scapegoat(struct rev_info *revs, struct commit *commit)
-{
-       if (!reverse) {
-               if (revs->first_parent_only &&
-                   commit->parents &&
-                   commit->parents->next) {
-                       free_commit_list(commit->parents->next);
-                       commit->parents->next = NULL;
-               }
-               return commit->parents;
-       }
-       return lookup_decoration(&revs->children, &commit->object);
-}
-
-static int num_scapegoats(struct rev_info *revs, struct commit *commit)
-{
-       struct commit_list *l = first_scapegoat(revs, commit);
-       return commit_list_count(l);
-}
-
-/* Distribute collected unsorted blames to the respected sorted lists
- * in the various origins.
- */
-static void distribute_blame(struct scoreboard *sb, struct blame_entry *blamed)
-{
-       blamed = blame_sort(blamed, compare_blame_suspect);
-       while (blamed)
-       {
-               struct origin *porigin = blamed->suspect;
-               struct blame_entry *suspects = NULL;
-               do {
-                       struct blame_entry *next = blamed->next;
-                       blamed->next = suspects;
-                       suspects = blamed;
-                       blamed = next;
-               } while (blamed && blamed->suspect == porigin);
-               suspects = reverse_blame(suspects, NULL);
-               queue_blames(sb, porigin, suspects);
-       }
-}
-
-#define MAXSG 16
-
-static void pass_blame(struct scoreboard *sb, struct origin *origin, int opt)
+static const char *nth_line_cb(void *data, long lno)
 {
-       struct rev_info *revs = sb->revs;
-       int i, pass, num_sg;
-       struct commit *commit = origin->commit;
-       struct commit_list *sg;
-       struct origin *sg_buf[MAXSG];
-       struct origin *porigin, **sg_origin = sg_buf;
-       struct blame_entry *toosmall = NULL;
-       struct blame_entry *blames, **blametail = &blames;
-
-       num_sg = num_scapegoats(revs, commit);
-       if (!num_sg)
-               goto finish;
-       else if (num_sg < ARRAY_SIZE(sg_buf))
-               memset(sg_buf, 0, sizeof(sg_buf));
-       else
-               sg_origin = xcalloc(num_sg, sizeof(*sg_origin));
-
-       /*
-        * The first pass looks for unrenamed path to optimize for
-        * common cases, then we look for renames in the second pass.
-        */
-       for (pass = 0; pass < 2 - no_whole_file_rename; pass++) {
-               struct origin *(*find)(struct scoreboard *,
-                                      struct commit *, struct origin *);
-               find = pass ? find_rename : find_origin;
-
-               for (i = 0, sg = first_scapegoat(revs, commit);
-                    i < num_sg && sg;
-                    sg = sg->next, i++) {
-                       struct commit *p = sg->item;
-                       int j, same;
-
-                       if (sg_origin[i])
-                               continue;
-                       if (parse_commit(p))
-                               continue;
-                       porigin = find(sb, p, origin);
-                       if (!porigin)
-                               continue;
-                       if (!hashcmp(porigin->blob_sha1, origin->blob_sha1)) {
-                               pass_whole_blame(sb, origin, porigin);
-                               origin_decref(porigin);
-                               goto finish;
-                       }
-                       for (j = same = 0; j < i; j++)
-                               if (sg_origin[j] &&
-                                   !hashcmp(sg_origin[j]->blob_sha1,
-                                            porigin->blob_sha1)) {
-                                       same = 1;
-                                       break;
-                               }
-                       if (!same)
-                               sg_origin[i] = porigin;
-                       else
-                               origin_decref(porigin);
-               }
-       }
-
-       num_commits++;
-       for (i = 0, sg = first_scapegoat(revs, commit);
-            i < num_sg && sg;
-            sg = sg->next, i++) {
-               struct origin *porigin = sg_origin[i];
-               if (!porigin)
-                       continue;
-               if (!origin->previous) {
-                       origin_incref(porigin);
-                       origin->previous = porigin;
-               }
-               pass_blame_to_parent(sb, origin, porigin);
-               if (!origin->suspects)
-                       goto finish;
-       }
-
-       /*
-        * Optionally find moves in parents' files.
-        */
-       if (opt & PICKAXE_BLAME_MOVE) {
-               filter_small(sb, &toosmall, &origin->suspects, blame_move_score);
-               if (origin->suspects) {
-                       for (i = 0, sg = first_scapegoat(revs, commit);
-                            i < num_sg && sg;
-                            sg = sg->next, i++) {
-                               struct origin *porigin = sg_origin[i];
-                               if (!porigin)
-                                       continue;
-                               find_move_in_parent(sb, &blametail, &toosmall, origin, porigin);
-                               if (!origin->suspects)
-                                       break;
-                       }
-               }
-       }
-
-       /*
-        * Optionally find copies from parents' files.
-        */
-       if (opt & PICKAXE_BLAME_COPY) {
-               if (blame_copy_score > blame_move_score)
-                       filter_small(sb, &toosmall, &origin->suspects, blame_copy_score);
-               else if (blame_copy_score < blame_move_score) {
-                       origin->suspects = blame_merge(origin->suspects, toosmall);
-                       toosmall = NULL;
-                       filter_small(sb, &toosmall, &origin->suspects, blame_copy_score);
-               }
-               if (!origin->suspects)
-                       goto finish;
-
-               for (i = 0, sg = first_scapegoat(revs, commit);
-                    i < num_sg && sg;
-                    sg = sg->next, i++) {
-                       struct origin *porigin = sg_origin[i];
-                       find_copy_in_parent(sb, &blametail, &toosmall,
-                                           origin, sg->item, porigin, opt);
-                       if (!origin->suspects)
-                               goto finish;
-               }
-       }
-
-finish:
-       *blametail = NULL;
-       distribute_blame(sb, blames);
-       /*
-        * prepend toosmall to origin->suspects
-        *
-        * There is no point in sorting: this ends up on a big
-        * unsorted list in the caller anyway.
-        */
-       if (toosmall) {
-               struct blame_entry **tail = &toosmall;
-               while (*tail)
-                       tail = &(*tail)->next;
-               *tail = origin->suspects;
-               origin->suspects = toosmall;
-       }
-       for (i = 0; i < num_sg; i++) {
-               if (sg_origin[i]) {
-                       drop_origin_blob(sg_origin[i]);
-                       origin_decref(sg_origin[i]);
-               }
-       }
-       drop_origin_blob(origin);
-       if (sg_buf != sg_origin)
-               free(sg_origin);
+       return blame_nth_line((struct blame_scoreboard *)data, lno);
 }
 
 /*
@@ -1571,13 +79,13 @@ static void pass_blame(struct scoreboard *sb, struct origin *origin, int opt)
 struct commit_info {
        struct strbuf author;
        struct strbuf author_mail;
-       unsigned long author_time;
+       timestamp_t author_time;
        struct strbuf author_tz;
 
        /* filled only when asked for details */
        struct strbuf committer;
        struct strbuf committer_mail;
-       unsigned long committer_time;
+       timestamp_t committer_time;
        struct strbuf committer_tz;
 
        struct strbuf summary;
@@ -1588,7 +96,7 @@ struct commit_info {
  */
 static void get_ac_line(const char *inbuf, const char *what,
        struct strbuf *name, struct strbuf *mail,
-       unsigned long *time, struct strbuf *tz)
+       timestamp_t *time, struct strbuf *tz)
 {
        struct ident_split ident;
        size_t len, maillen, namelen;
@@ -1701,13 +209,23 @@ static void get_commit_info(struct commit *commit,
 }
 
 /*
+ * Write out any suspect information which depends on the path. This must be
+ * handled separately from emit_one_suspect_detail(), because a given commit
+ * may have changes in multiple paths. So this needs to appear each time
+ * we mention a new group.
+ *
  * To allow LF and other nonportable characters in pathnames,
  * they are c-style quoted as needed.
  */
-static void write_filename_info(const char *path)
+static void write_filename_info(struct blame_origin *suspect)
 {
+       if (suspect->previous) {
+               struct blame_origin *prev = suspect->previous;
+               printf("previous %s ", oid_to_hex(&prev->commit->object.oid));
+               write_name_quoted(prev->path, stdout, '\n');
+       }
        printf("filename ");
-       write_name_quoted(path, stdout, '\n');
+       write_name_quoted(suspect->path, stdout, '\n');
 }
 
 /*
@@ -1716,7 +234,7 @@ static void write_filename_info(const char *path)
  * the first time each commit appears in the output (unless the
  * user has specifically asked for us to repeat).
  */
-static int emit_one_suspect_detail(struct origin *suspect, int repeat)
+static int emit_one_suspect_detail(struct blame_origin *suspect, int repeat)
 {
        struct commit_info ci;
 
@@ -1727,20 +245,15 @@ static int emit_one_suspect_detail(struct origin *suspect, int repeat)
        get_commit_info(suspect->commit, &ci, 1);
        printf("author %s\n", ci.author.buf);
        printf("author-mail %s\n", ci.author_mail.buf);
-       printf("author-time %lu\n", ci.author_time);
+       printf("author-time %"PRItime"\n", ci.author_time);
        printf("author-tz %s\n", ci.author_tz.buf);
        printf("committer %s\n", ci.committer.buf);
        printf("committer-mail %s\n", ci.committer_mail.buf);
-       printf("committer-time %lu\n", ci.committer_time);
+       printf("committer-time %"PRItime"\n", ci.committer_time);
        printf("committer-tz %s\n", ci.committer_tz.buf);
        printf("summary %s\n", ci.summary.buf);
        if (suspect->commit->object.flags & UNINTERESTING)
                printf("boundary\n");
-       if (suspect->previous) {
-               struct origin *prev = suspect->previous;
-               printf("previous %s ", oid_to_hex(&prev->commit->object.oid));
-               write_name_quoted(prev->path, stdout, '\n');
-       }
 
        commit_info_destroy(&ci);
 
@@ -1751,105 +264,32 @@ static int emit_one_suspect_detail(struct origin *suspect, int repeat)
  * The blame_entry is found to be guilty for the range.
  * Show it in incremental output.
  */
-static void found_guilty_entry(struct blame_entry *ent,
-                          struct progress_info *pi)
+static void found_guilty_entry(struct blame_entry *ent, void *data)
 {
+       struct progress_info *pi = (struct progress_info *)data;
+
        if (incremental) {
-               struct origin *suspect = ent->suspect;
+               struct blame_origin *suspect = ent->suspect;
 
                printf("%s %d %d %d\n",
                       oid_to_hex(&suspect->commit->object.oid),
                       ent->s_lno + 1, ent->lno + 1, ent->num_lines);
                emit_one_suspect_detail(suspect, 0);
-               write_filename_info(suspect->path);
+               write_filename_info(suspect);
                maybe_flush_or_die(stdout, "stdout");
        }
        pi->blamed_lines += ent->num_lines;
        display_progress(pi->progress, pi->blamed_lines);
 }
 
-/*
- * The main loop -- while we have blobs with lines whose true origin
- * is still unknown, pick one blob, and allow its lines to pass blames
- * to its parents. */
-static void assign_blame(struct scoreboard *sb, int opt)
-{
-       struct rev_info *revs = sb->revs;
-       struct commit *commit = prio_queue_get(&sb->commits);
-       struct progress_info pi = { NULL, 0 };
-
-       if (show_progress)
-               pi.progress = start_progress_delay(_("Blaming lines"),
-                                                  sb->num_lines, 50, 1);
-
-       while (commit) {
-               struct blame_entry *ent;
-               struct origin *suspect = commit->util;
-
-               /* find one suspect to break down */
-               while (suspect && !suspect->suspects)
-                       suspect = suspect->next;
-
-               if (!suspect) {
-                       commit = prio_queue_get(&sb->commits);
-                       continue;
-               }
-
-               assert(commit == suspect->commit);
-
-               /*
-                * We will use this suspect later in the loop,
-                * so hold onto it in the meantime.
-                */
-               origin_incref(suspect);
-               parse_commit(commit);
-               if (reverse ||
-                   (!(commit->object.flags & UNINTERESTING) &&
-                    !(revs->max_age != -1 && commit->date < revs->max_age)))
-                       pass_blame(sb, suspect, opt);
-               else {
-                       commit->object.flags |= UNINTERESTING;
-                       if (commit->object.parsed)
-                               mark_parents_uninteresting(commit);
-               }
-               /* treat root commit as boundary */
-               if (!commit->parents && !show_root)
-                       commit->object.flags |= UNINTERESTING;
-
-               /* Take responsibility for the remaining entries */
-               ent = suspect->suspects;
-               if (ent) {
-                       suspect->guilty = 1;
-                       for (;;) {
-                               struct blame_entry *next = ent->next;
-                               found_guilty_entry(ent, &pi);
-                               if (next) {
-                                       ent = next;
-                                       continue;
-                               }
-                               ent->next = sb->ent;
-                               sb->ent = suspect->suspects;
-                               suspect->suspects = NULL;
-                               break;
-                       }
-               }
-               origin_decref(suspect);
-
-               if (DEBUG) /* sanity */
-                       sanity_check_refcnt(sb);
-       }
-
-       stop_progress(&pi.progress);
-}
-
-static const char *format_time(unsigned long time, const char *tz_str,
+static const char *format_time(timestamp_t time, const char *tz_str,
                               int show_raw_time)
 {
        static struct strbuf time_buf = STRBUF_INIT;
 
        strbuf_reset(&time_buf);
        if (show_raw_time) {
-               strbuf_addf(&time_buf, "%lu %s", time, tz_str);
+               strbuf_addf(&time_buf, "%"PRItime" %s", time, tz_str);
        }
        else {
                const char *time_str;
@@ -1881,23 +321,23 @@ static const char *format_time(unsigned long time, const char *tz_str,
 #define OUTPUT_SHOW_EMAIL      0400
 #define OUTPUT_LINE_PORCELAIN 01000
 
-static void emit_porcelain_details(struct origin *suspect, int repeat)
+static void emit_porcelain_details(struct blame_origin *suspect, int repeat)
 {
        if (emit_one_suspect_detail(suspect, repeat) ||
            (suspect->commit->object.flags & MORE_THAN_ONE_PATH))
-               write_filename_info(suspect->path);
+               write_filename_info(suspect);
 }
 
-static void emit_porcelain(struct scoreboard *sb, struct blame_entry *ent,
+static void emit_porcelain(struct blame_scoreboard *sb, struct blame_entry *ent,
                           int opt)
 {
        int repeat = opt & OUTPUT_LINE_PORCELAIN;
        int cnt;
        const char *cp;
-       struct origin *suspect = ent->suspect;
-       char hex[GIT_SHA1_HEXSZ + 1];
+       struct blame_origin *suspect = ent->suspect;
+       char hex[GIT_MAX_HEXSZ + 1];
 
-       sha1_to_hex_r(hex, suspect->commit->object.oid.hash);
+       oid_to_hex_r(hex, &suspect->commit->object.oid);
        printf("%s %d %d %d\n",
               hex,
               ent->s_lno + 1,
@@ -1905,7 +345,7 @@ static void emit_porcelain(struct scoreboard *sb, struct blame_entry *ent,
               ent->num_lines);
        emit_porcelain_details(suspect, repeat);
 
-       cp = nth_line(sb, ent->lno);
+       cp = blame_nth_line(sb, ent->lno);
        for (cnt = 0; cnt < ent->num_lines; cnt++) {
                char ch;
                if (cnt) {
@@ -1927,22 +367,22 @@ static void emit_porcelain(struct scoreboard *sb, struct blame_entry *ent,
                putchar('\n');
 }
 
-static void emit_other(struct scoreboard *sb, struct blame_entry *ent, int opt)
+static void emit_other(struct blame_scoreboard *sb, struct blame_entry *ent, int opt)
 {
        int cnt;
        const char *cp;
-       struct origin *suspect = ent->suspect;
+       struct blame_origin *suspect = ent->suspect;
        struct commit_info ci;
-       char hex[GIT_SHA1_HEXSZ + 1];
+       char hex[GIT_MAX_HEXSZ + 1];
        int show_raw_time = !!(opt & OUTPUT_RAW_TIMESTAMP);
 
        get_commit_info(suspect->commit, &ci, 1);
-       sha1_to_hex_r(hex, suspect->commit->object.oid.hash);
+       oid_to_hex_r(hex, &suspect->commit->object.oid);
 
-       cp = nth_line(sb, ent->lno);
+       cp = blame_nth_line(sb, ent->lno);
        for (cnt = 0; cnt < ent->num_lines; cnt++) {
                char ch;
-               int length = (opt & OUTPUT_LONG_OBJECT_NAME) ? 40 : abbrev;
+               int length = (opt & OUTPUT_LONG_OBJECT_NAME) ? GIT_SHA1_HEXSZ : abbrev;
 
                if (suspect->commit->object.flags & UNINTERESTING) {
                        if (blank_boundary)
@@ -2006,14 +446,14 @@ static void emit_other(struct scoreboard *sb, struct blame_entry *ent, int opt)
        commit_info_destroy(&ci);
 }
 
-static void output(struct scoreboard *sb, int option)
+static void output(struct blame_scoreboard *sb, int option)
 {
        struct blame_entry *ent;
 
        if (option & OUTPUT_PORCELAIN) {
                for (ent = sb->ent; ent; ent = ent->next) {
                        int count = 0;
-                       struct origin *suspect;
+                       struct blame_origin *suspect;
                        struct commit *commit = ent->suspect->commit;
                        if (commit->object.flags & MORE_THAN_ONE_PATH)
                                continue;
@@ -2035,40 +475,6 @@ static void output(struct scoreboard *sb, int option)
        }
 }
 
-static const char *get_next_line(const char *start, const char *end)
-{
-       const char *nl = memchr(start, '\n', end - start);
-       return nl ? nl + 1 : end;
-}
-
-/*
- * To allow quick access to the contents of nth line in the
- * final image, prepare an index in the scoreboard.
- */
-static int prepare_lines(struct scoreboard *sb)
-{
-       const char *buf = sb->final_buf;
-       unsigned long len = sb->final_buf_size;
-       const char *end = buf + len;
-       const char *p;
-       int *lineno;
-       int num = 0;
-
-       for (p = buf; p < end; p = get_next_line(p, end))
-               num++;
-
-       ALLOC_ARRAY(sb->lineno, num + 1);
-       lineno = sb->lineno;
-
-       for (p = buf; p < end; p = get_next_line(p, end))
-               *lineno++ = p - buf;
-
-       *lineno = len;
-
-       sb->num_lines = num;
-       return sb->num_lines;
-}
-
 /*
  * Add phony grafts for use with -S; this is primarily to
  * support git's cvsserver that wants to give a linear history
@@ -2076,7 +482,7 @@ static int prepare_lines(struct scoreboard *sb)
  */
 static int read_ancestry(const char *graft_file)
 {
-       FILE *fp = fopen(graft_file, "r");
+       FILE *fp = fopen_or_warn(graft_file, "r");
        struct strbuf buf = STRBUF_INIT;
        if (!fp)
                return -1;
@@ -2091,7 +497,7 @@ static int read_ancestry(const char *graft_file)
        return 0;
 }
 
-static int update_auto_abbrev(int auto_abbrev, struct origin *suspect)
+static int update_auto_abbrev(int auto_abbrev, struct blame_origin *suspect)
 {
        const char *uniq = find_unique_abbrev(suspect->commit->object.oid.hash,
                                              auto_abbrev);
@@ -2105,17 +511,17 @@ static int update_auto_abbrev(int auto_abbrev, struct origin *suspect)
  * How many columns do we need to show line numbers, authors,
  * and filenames?
  */
-static void find_alignment(struct scoreboard *sb, int *option)
+static void find_alignment(struct blame_scoreboard *sb, int *option)
 {
        int longest_src_lines = 0;
        int longest_dst_lines = 0;
        unsigned largest_score = 0;
        struct blame_entry *e;
        int compute_auto_abbrev = (abbrev < 0);
-       int auto_abbrev = default_abbrev;
+       int auto_abbrev = DEFAULT_ABBREV;
 
        for (e = sb->ent; e; e = e->next) {
-               struct origin *suspect = e->suspect;
+               struct blame_origin *suspect = e->suspect;
                int num;
 
                if (compute_auto_abbrev)
@@ -2143,8 +549,8 @@ static void find_alignment(struct scoreboard *sb, int *option)
                num = e->lno + e->num_lines;
                if (longest_dst_lines < num)
                        longest_dst_lines = num;
-               if (largest_score < ent_score(sb, e))
-                       largest_score = ent_score(sb, e);
+               if (largest_score < blame_entry_score(sb, e))
+                       largest_score = blame_entry_score(sb, e);
        }
        max_orig_digits = decimal_width(longest_src_lines);
        max_digits = decimal_width(longest_dst_lines);
@@ -2155,31 +561,12 @@ static void find_alignment(struct scoreboard *sb, int *option)
                abbrev = auto_abbrev + 1;
 }
 
-/*
- * For debugging -- origin is refcounted, and this asserts that
- * we do not underflow.
- */
-static void sanity_check_refcnt(struct scoreboard *sb)
+static void sanity_check_on_fail(struct blame_scoreboard *sb, int baa)
 {
-       int baa = 0;
-       struct blame_entry *ent;
-
-       for (ent = sb->ent; ent; ent = ent->next) {
-               /* Nobody should have zero or negative refcnt */
-               if (ent->suspect->refcnt <= 0) {
-                       fprintf(stderr, "%s in %s has negative refcnt %d\n",
-                               ent->suspect->path,
-                               oid_to_hex(&ent->suspect->commit->object.oid),
-                               ent->suspect->refcnt);
-                       baa = 1;
-               }
-       }
-       if (baa) {
-               int opt = 0160;
-               find_alignment(sb, &opt);
-               output(sb, opt);
-               die("Baa %d!", baa);
-       }
+       int opt = OUTPUT_SHOW_SCORE | OUTPUT_SHOW_NUMBER | OUTPUT_SHOW_NAME;
+       find_alignment(sb, &opt);
+       output(sb, opt);
+       die("Baa %d!", baa);
 }
 
 static unsigned parse_score(const char *arg)
@@ -2221,262 +608,14 @@ static int git_blame_config(const char *var, const char *value, void *cb)
                return 0;
        }
 
+       if (git_diff_heuristic_config(var, value, cb) < 0)
+               return -1;
        if (userdiff_config(var, value) < 0)
                return -1;
 
        return git_default_config(var, value, cb);
 }
 
-static void verify_working_tree_path(struct commit *work_tree, const char *path)
-{
-       struct commit_list *parents;
-
-       for (parents = work_tree->parents; parents; parents = parents->next) {
-               const unsigned char *commit_sha1 = parents->item->object.oid.hash;
-               unsigned char blob_sha1[20];
-               unsigned mode;
-
-               if (!get_tree_entry(commit_sha1, path, blob_sha1, &mode) &&
-                   sha1_object_info(blob_sha1, NULL) == OBJ_BLOB)
-                       return;
-       }
-       die("no such path '%s' in HEAD", path);
-}
-
-static struct commit_list **append_parent(struct commit_list **tail, const unsigned char *sha1)
-{
-       struct commit *parent;
-
-       parent = lookup_commit_reference(sha1);
-       if (!parent)
-               die("no such commit %s", sha1_to_hex(sha1));
-       return &commit_list_insert(parent, tail)->next;
-}
-
-static void append_merge_parents(struct commit_list **tail)
-{
-       int merge_head;
-       struct strbuf line = STRBUF_INIT;
-
-       merge_head = open(git_path_merge_head(), O_RDONLY);
-       if (merge_head < 0) {
-               if (errno == ENOENT)
-                       return;
-               die("cannot open '%s' for reading", git_path_merge_head());
-       }
-
-       while (!strbuf_getwholeline_fd(&line, merge_head, '\n')) {
-               unsigned char sha1[20];
-               if (line.len < 40 || get_sha1_hex(line.buf, sha1))
-                       die("unknown line in '%s': %s", git_path_merge_head(), line.buf);
-               tail = append_parent(tail, sha1);
-       }
-       close(merge_head);
-       strbuf_release(&line);
-}
-
-/*
- * This isn't as simple as passing sb->buf and sb->len, because we
- * want to transfer ownership of the buffer to the commit (so we
- * must use detach).
- */
-static void set_commit_buffer_from_strbuf(struct commit *c, struct strbuf *sb)
-{
-       size_t len;
-       void *buf = strbuf_detach(sb, &len);
-       set_commit_buffer(c, buf, len);
-}
-
-/*
- * Prepare a dummy commit that represents the work tree (or staged) item.
- * Note that annotating work tree item never works in the reverse.
- */
-static struct commit *fake_working_tree_commit(struct diff_options *opt,
-                                              const char *path,
-                                              const char *contents_from)
-{
-       struct commit *commit;
-       struct origin *origin;
-       struct commit_list **parent_tail, *parent;
-       unsigned char head_sha1[20];
-       struct strbuf buf = STRBUF_INIT;
-       const char *ident;
-       time_t now;
-       int size, len;
-       struct cache_entry *ce;
-       unsigned mode;
-       struct strbuf msg = STRBUF_INIT;
-
-       read_cache();
-       time(&now);
-       commit = alloc_commit_node();
-       commit->object.parsed = 1;
-       commit->date = now;
-       parent_tail = &commit->parents;
-
-       if (!resolve_ref_unsafe("HEAD", RESOLVE_REF_READING, head_sha1, NULL))
-               die("no such ref: HEAD");
-
-       parent_tail = append_parent(parent_tail, head_sha1);
-       append_merge_parents(parent_tail);
-       verify_working_tree_path(commit, path);
-
-       origin = make_origin(commit, path);
-
-       ident = fmt_ident("Not Committed Yet", "not.committed.yet", NULL, 0);
-       strbuf_addstr(&msg, "tree 0000000000000000000000000000000000000000\n");
-       for (parent = commit->parents; parent; parent = parent->next)
-               strbuf_addf(&msg, "parent %s\n",
-                           oid_to_hex(&parent->item->object.oid));
-       strbuf_addf(&msg,
-                   "author %s\n"
-                   "committer %s\n\n"
-                   "Version of %s from %s\n",
-                   ident, ident, path,
-                   (!contents_from ? path :
-                    (!strcmp(contents_from, "-") ? "standard input" : contents_from)));
-       set_commit_buffer_from_strbuf(commit, &msg);
-
-       if (!contents_from || strcmp("-", contents_from)) {
-               struct stat st;
-               const char *read_from;
-               char *buf_ptr;
-               unsigned long buf_len;
-
-               if (contents_from) {
-                       if (stat(contents_from, &st) < 0)
-                               die_errno("Cannot stat '%s'", contents_from);
-                       read_from = contents_from;
-               }
-               else {
-                       if (lstat(path, &st) < 0)
-                               die_errno("Cannot lstat '%s'", path);
-                       read_from = path;
-               }
-               mode = canon_mode(st.st_mode);
-
-               switch (st.st_mode & S_IFMT) {
-               case S_IFREG:
-                       if (DIFF_OPT_TST(opt, ALLOW_TEXTCONV) &&
-                           textconv_object(read_from, mode, null_sha1, 0, &buf_ptr, &buf_len))
-                               strbuf_attach(&buf, buf_ptr, buf_len, buf_len + 1);
-                       else if (strbuf_read_file(&buf, read_from, st.st_size) != st.st_size)
-                               die_errno("cannot open or read '%s'", read_from);
-                       break;
-               case S_IFLNK:
-                       if (strbuf_readlink(&buf, read_from, st.st_size) < 0)
-                               die_errno("cannot readlink '%s'", read_from);
-                       break;
-               default:
-                       die("unsupported file type %s", read_from);
-               }
-       }
-       else {
-               /* Reading from stdin */
-               mode = 0;
-               if (strbuf_read(&buf, 0, 0) < 0)
-                       die_errno("failed to read from stdin");
-       }
-       convert_to_git(path, buf.buf, buf.len, &buf, 0);
-       origin->file.ptr = buf.buf;
-       origin->file.size = buf.len;
-       pretend_sha1_file(buf.buf, buf.len, OBJ_BLOB, origin->blob_sha1);
-
-       /*
-        * Read the current index, replace the path entry with
-        * origin->blob_sha1 without mucking with its mode or type
-        * bits; we are not going to write this index out -- we just
-        * want to run "diff-index --cached".
-        */
-       discard_cache();
-       read_cache();
-
-       len = strlen(path);
-       if (!mode) {
-               int pos = cache_name_pos(path, len);
-               if (0 <= pos)
-                       mode = active_cache[pos]->ce_mode;
-               else
-                       /* Let's not bother reading from HEAD tree */
-                       mode = S_IFREG | 0644;
-       }
-       size = cache_entry_size(len);
-       ce = xcalloc(1, size);
-       hashcpy(ce->sha1, origin->blob_sha1);
-       memcpy(ce->name, path, len);
-       ce->ce_flags = create_ce_flags(0);
-       ce->ce_namelen = len;
-       ce->ce_mode = create_ce_mode(mode);
-       add_cache_entry(ce, ADD_CACHE_OK_TO_ADD|ADD_CACHE_OK_TO_REPLACE);
-
-       cache_tree_invalidate_path(&the_index, path);
-
-       return commit;
-}
-
-static struct commit *find_single_final(struct rev_info *revs,
-                                       const char **name_p)
-{
-       int i;
-       struct commit *found = NULL;
-       const char *name = NULL;
-
-       for (i = 0; i < revs->pending.nr; i++) {
-               struct object *obj = revs->pending.objects[i].item;
-               if (obj->flags & UNINTERESTING)
-                       continue;
-               while (obj->type == OBJ_TAG)
-                       obj = deref_tag(obj, NULL, 0);
-               if (obj->type != OBJ_COMMIT)
-                       die("Non commit %s?", revs->pending.objects[i].name);
-               if (found)
-                       die("More than one commit to dig from %s and %s?",
-                           revs->pending.objects[i].name, name);
-               found = (struct commit *)obj;
-               name = revs->pending.objects[i].name;
-       }
-       if (name_p)
-               *name_p = name;
-       return found;
-}
-
-static char *prepare_final(struct scoreboard *sb)
-{
-       const char *name;
-       sb->final = find_single_final(sb->revs, &name);
-       return xstrdup_or_null(name);
-}
-
-static char *prepare_initial(struct scoreboard *sb)
-{
-       int i;
-       const char *final_commit_name = NULL;
-       struct rev_info *revs = sb->revs;
-
-       /*
-        * There must be one and only one negative commit, and it must be
-        * the boundary.
-        */
-       for (i = 0; i < revs->pending.nr; i++) {
-               struct object *obj = revs->pending.objects[i].item;
-               if (!(obj->flags & UNINTERESTING))
-                       continue;
-               while (obj->type == OBJ_TAG)
-                       obj = deref_tag(obj, NULL, 0);
-               if (obj->type != OBJ_COMMIT)
-                       die("Non commit %s?", revs->pending.objects[i].name);
-               if (sb->final)
-                       die("More than one commit to dig down to %s and %s?",
-                           revs->pending.objects[i].name,
-                           final_commit_name);
-               sb->final = (struct commit *) obj;
-               final_commit_name = revs->pending.objects[i].name;
-       }
-       if (!final_commit_name)
-               die("No commit to dig down to?");
-       return xstrdup(final_commit_name);
-}
-
 static int blame_copy_callback(const struct option *option, const char *arg, int unset)
 {
        int *opt = option->value;
@@ -2514,20 +653,18 @@ int cmd_blame(int argc, const char **argv, const char *prefix)
 {
        struct rev_info revs;
        const char *path;
-       struct scoreboard sb;
-       struct origin *o;
+       struct blame_scoreboard sb;
+       struct blame_origin *o;
        struct blame_entry *ent = NULL;
        long dashdash_pos, lno;
-       char *final_commit_name = NULL;
-       enum object_type type;
-       struct commit *final_commit = NULL;
-
-       static struct string_list range_list;
-       static int output_option = 0, opt = 0;
-       static int show_stats = 0;
-       static const char *revs_file = NULL;
-       static const char *contents_from = NULL;
-       static const struct option options[] = {
+       struct progress_info pi = { NULL, 0 };
+
+       struct string_list range_list = STRING_LIST_INIT_NODUP;
+       int output_option = 0, opt = 0;
+       int show_stats = 0;
+       const char *revs_file = NULL;
+       const char *contents_from = NULL;
+       const struct option options[] = {
                OPT_BOOL(0, "incremental", &incremental, N_("Show blame entries as we find them, incrementally")),
                OPT_BOOL('b', NULL, &blank_boundary, N_("Show blank SHA-1 for boundary commits (Default: off)")),
                OPT_BOOL(0, "root", &show_root, N_("Do not treat root commits as boundaries (Default: off)")),
@@ -2544,6 +681,14 @@ int cmd_blame(int argc, const char **argv, const char *prefix)
                OPT_BIT('s', NULL, &output_option, N_("Suppress author name and timestamp (Default: off)"), OUTPUT_NO_AUTHOR),
                OPT_BIT('e', "show-email", &output_option, N_("Show author email instead of name (Default: off)"), OUTPUT_SHOW_EMAIL),
                OPT_BIT('w', NULL, &xdl_opts, N_("Ignore whitespace differences"), XDF_IGNORE_WHITESPACE),
+
+               /*
+                * The following two options are parsed by parse_revision_opt()
+                * and are only included here to get included in the "-h"
+                * output:
+                */
+               { OPTION_LOWLEVEL_CALLBACK, 0, "indent-heuristic", NULL, NULL, N_("Use an experimental heuristic to improve diffs"), PARSE_OPT_NOARG, parse_opt_unknown_cb },
+
                OPT_BIT(0, "minimal", &xdl_opts, N_("Spend extra cycles to find better match"), XDF_NEED_MINIMAL),
                OPT_STRING('S', NULL, &revs_file, N_("file"), N_("Use revisions from <file> instead of calling git-rev-list")),
                OPT_STRING(0, "contents", &contents_from, N_("file"), N_("Use <file>'s contents as the final image")),
@@ -2590,19 +735,22 @@ int cmd_blame(int argc, const char **argv, const char *prefix)
        }
 parse_done:
        no_whole_file_rename = !DIFF_OPT_TST(&revs.diffopt, FOLLOW_RENAMES);
+       xdl_opts |= revs.diffopt.xdl_opts & XDF_INDENT_HEURISTIC;
        DIFF_OPT_CLR(&revs.diffopt, FOLLOW_RENAMES);
        argc = parse_options_end(&ctx);
 
        if (incremental || (output_option & OUTPUT_PORCELAIN)) {
                if (show_progress > 0)
-                       die("--progress can't be used with --incremental or porcelain formats");
+                       die(_("--progress can't be used with --incremental or porcelain formats"));
                show_progress = 0;
        } else if (show_progress < 0)
                show_progress = isatty(2);
 
-       if (0 < abbrev)
+       if (0 < abbrev && abbrev < GIT_SHA1_HEXSZ)
                /* one more abbrev length is needed for the boundary commit */
                abbrev++;
+       else if (!abbrev)
+               abbrev = GIT_SHA1_HEXSZ;
 
        if (revs_file && read_ancestry(revs_file))
                die_errno("reading graft file '%s' failed", revs_file);
@@ -2628,16 +776,22 @@ int cmd_blame(int argc, const char **argv, const char *prefix)
        case DATE_RAW:
                blame_date_width = sizeof("1161298804 -0700");
                break;
+       case DATE_UNIX:
+               blame_date_width = sizeof("1161298804");
+               break;
        case DATE_SHORT:
                blame_date_width = sizeof("2006-10-19");
                break;
        case DATE_RELATIVE:
-               /* TRANSLATORS: This string is used to tell us the maximum
-                  display width for a relative timestamp in "git blame"
-                  output.  For C locale, "4 years, 11 months ago", which
-                  takes 22 places, is the longest among various forms of
-                  relative timestamps, but your language may need more or
-                  fewer display columns. */
+               /*
+                * TRANSLATORS: This string is used to tell us the
+                * maximum display width for a relative timestamp in
+                * "git blame" output.  For C locale, "4 years, 11
+                * months ago", which takes 22 places, is the longest
+                * among various forms of relative timestamps, but
+                * your language may need more or fewer display
+                * columns.
+                */
                blame_date_width = utf8_strwidth(_("4 years, 11 months ago")) + 1; /* add the null */
                break;
        case DATE_NORMAL:
@@ -2653,11 +807,6 @@ int cmd_blame(int argc, const char **argv, const char *prefix)
                opt |= (PICKAXE_BLAME_COPY | PICKAXE_BLAME_MOVE |
                        PICKAXE_BLAME_COPY_HARDER);
 
-       if (!blame_move_score)
-               blame_move_score = BLAME_DEFAULT_MOVE_SCORE;
-       if (!blame_copy_score)
-               blame_copy_score = BLAME_DEFAULT_COPY_SCORE;
-
        /*
         * We have collected options unknown to us in argv[1..unk]
         * which are to be passed to revision machinery if we are
@@ -2710,97 +859,16 @@ int cmd_blame(int argc, const char **argv, const char *prefix)
 
        revs.disable_stdin = 1;
        setup_revisions(argc, argv, &revs, NULL);
-       memset(&sb, 0, sizeof(sb));
 
+       init_scoreboard(&sb);
        sb.revs = &revs;
-       if (!reverse) {
-               final_commit_name = prepare_final(&sb);
-               sb.commits.compare = compare_commits_by_commit_date;
-       }
-       else if (contents_from)
-               die("--contents and --reverse do not blend well.");
-       else {
-               final_commit_name = prepare_initial(&sb);
-               sb.commits.compare = compare_commits_by_reverse_commit_date;
-               if (revs.first_parent_only)
-                       revs.children.name = NULL;
-       }
-
-       if (!sb.final) {
-               /*
-                * "--not A B -- path" without anything positive;
-                * do not default to HEAD, but use the working tree
-                * or "--contents".
-                */
-               setup_work_tree();
-               sb.final = fake_working_tree_commit(&sb.revs->diffopt,
-                                                   path, contents_from);
-               add_pending_object(&revs, &(sb.final->object), ":");
-       }
-       else if (contents_from)
-               die("Cannot use --contents with final commit object name");
-
-       if (reverse && revs.first_parent_only) {
-               final_commit = find_single_final(sb.revs, NULL);
-               if (!final_commit)
-                       die("--reverse and --first-parent together require specified latest commit");
-       }
-
-       /*
-        * If we have bottom, this will mark the ancestors of the
-        * bottom commits we would reach while traversing as
-        * uninteresting.
-        */
-       if (prepare_revision_walk(&revs))
-               die(_("revision walk setup failed"));
-
-       if (reverse && revs.first_parent_only) {
-               struct commit *c = final_commit;
-
-               sb.revs->children.name = "children";
-               while (c->parents &&
-                      oidcmp(&c->object.oid, &sb.final->object.oid)) {
-                       struct commit_list *l = xcalloc(1, sizeof(*l));
-
-                       l->item = c;
-                       if (add_decoration(&sb.revs->children,
-                                          &c->parents->item->object, l))
-                               die("BUG: not unique item in first-parent chain");
-                       c = c->parents->item;
-               }
-
-               if (oidcmp(&c->object.oid, &sb.final->object.oid))
-                       die("--reverse --first-parent together require range along first-parent chain");
-       }
-
-       if (is_null_oid(&sb.final->object.oid)) {
-               o = sb.final->util;
-               sb.final_buf = xmemdupz(o->file.ptr, o->file.size);
-               sb.final_buf_size = o->file.size;
-       }
-       else {
-               o = get_origin(&sb, sb.final, path);
-               if (fill_blob_sha1_and_mode(o))
-                       die("no such path %s in %s", path, final_commit_name);
-
-               if (DIFF_OPT_TST(&sb.revs->diffopt, ALLOW_TEXTCONV) &&
-                   textconv_object(path, o->mode, o->blob_sha1, 1, (char **) &sb.final_buf,
-                                   &sb.final_buf_size))
-                       ;
-               else
-                       sb.final_buf = read_sha1_file(o->blob_sha1, &type,
-                                                     &sb.final_buf_size);
-
-               if (!sb.final_buf)
-                       die("Cannot read blob %s for path %s",
-                           sha1_to_hex(o->blob_sha1),
-                           path);
-       }
-       num_read_blob++;
-       lno = prepare_lines(&sb);
+       sb.contents_from = contents_from;
+       sb.reverse = reverse;
+       setup_scoreboard(&sb, path, &o);
+       lno = sb.num_lines;
 
        if (lno && !range_list.nr)
-               string_list_append(&range_list, xstrdup("1"));
+               string_list_append(&range_list, "1");
 
        anchor = 1;
        range_set_init(&ranges, range_list.nr);
@@ -2811,7 +879,9 @@ int cmd_blame(int argc, const char **argv, const char *prefix)
                                    &bottom, &top, sb.path))
                        usage(blame_usage);
                if (lno < top || ((lno || bottom) && lno < bottom))
-                       die("file %s has only %lu lines", path, lno);
+                       die(Q_("file %s has only %lu line",
+                              "file %s has only %lu lines",
+                              lno), path, lno);
                if (bottom < 1)
                        bottom = 1;
                if (top < 1)
@@ -2824,22 +894,13 @@ int cmd_blame(int argc, const char **argv, const char *prefix)
 
        for (range_i = ranges.nr; range_i > 0; --range_i) {
                const struct range *r = &ranges.ranges[range_i - 1];
-               long bottom = r->start;
-               long top = r->end;
-               struct blame_entry *next = ent;
-               ent = xcalloc(1, sizeof(*ent));
-               ent->lno = bottom;
-               ent->num_lines = top - bottom;
-               ent->suspect = o;
-               ent->s_lno = bottom;
-               ent->next = next;
-               origin_incref(o);
+               ent = blame_entry_prepend(ent, r->start, r->end, o);
        }
 
        o->suspects = ent;
        prio_queue_put(&sb.commits, o->commit);
 
-       origin_decref(o);
+       blame_origin_decref(o);
 
        range_set_release(&ranges);
        string_list_clear(&range_list, 0);
@@ -2847,21 +908,38 @@ int cmd_blame(int argc, const char **argv, const char *prefix)
        sb.ent = NULL;
        sb.path = path;
 
+       if (blame_move_score)
+               sb.move_score = blame_move_score;
+       if (blame_copy_score)
+               sb.copy_score = blame_copy_score;
+
+       sb.debug = DEBUG;
+       sb.on_sanity_fail = &sanity_check_on_fail;
+
+       sb.show_root = show_root;
+       sb.xdl_opts = xdl_opts;
+       sb.no_whole_file_rename = no_whole_file_rename;
+
        read_mailmap(&mailmap, NULL);
 
+       sb.found_guilty_entry = &found_guilty_entry;
+       sb.found_guilty_entry_data = &pi;
+       if (show_progress)
+               pi.progress = start_progress_delay(_("Blaming lines"),
+                                                  sb.num_lines, 50, 1);
+
        assign_blame(&sb, opt);
 
+       stop_progress(&pi.progress);
+
        if (!incremental)
                setup_pager();
-
-       free(final_commit_name);
-
-       if (incremental)
+       else
                return 0;
 
-       sb.ent = blame_sort(sb.ent, compare_blame_final);
+       blame_sort_final(&sb);
 
-       coalesce(&sb);
+       blame_coalesce(&sb);
 
        if (!(output_option & OUTPUT_PORCELAIN))
                find_alignment(&sb, &output_option);
@@ -2875,9 +953,9 @@ int cmd_blame(int argc, const char **argv, const char *prefix)
        }
 
        if (show_stats) {
-               printf("num read blob: %d\n", num_read_blob);
-               printf("num get patch: %d\n", num_get_patch);
-               printf("num commits: %d\n", num_commits);
+               printf("num read blob: %d\n", sb.num_read_blob);
+               printf("num get patch: %d\n", sb.num_get_patch);
+               printf("num commits: %d\n", sb.num_commits);
        }
        return 0;
 }