Signed-off-by: Jeff Smith <whydoubt@xxxxxxxxx>
---
Makefile | 1 +
builtin/blame.c | 1358 +------------------------------------------------------
scoreboard.c | 1296 ++++++++++++++++++++++++++++++++++++++++++++++++++++
scoreboard.h | 74 +++
4 files changed, 1372 insertions(+), 1357 deletions(-)
create mode 100644 scoreboard.c
create mode 100644 scoreboard.h
diff --git a/Makefile b/Makefile
index b197a37..6e6726a 100644
--- a/Makefile
+++ b/Makefile
@@ -827,6 +827,7 @@ LIB_OBJS += rerere.o
LIB_OBJS += resolve-undo.o
LIB_OBJS += revision.o
LIB_OBJS += run-command.o
+LIB_OBJS += scoreboard.o
LIB_OBJS += send-pack.o
LIB_OBJS += sequencer.o
LIB_OBJS += server-info.o
diff --git a/builtin/blame.c b/builtin/blame.c
index dc7600c..0af99e3 100644
--- a/builtin/blame.c
+++ b/builtin/blame.c
@@ -12,13 +12,10 @@
#include "tag.h"
#include "tree-walk.h"
#include "diff.h"
-#include "diffcore.h"
#include "revision.h"
#include "quote.h"
-#include "xdiff-interface.h"
#include "string-list.h"
#include "mailmap.h"
-#include "mergesort.h"
#include "parse-options.h"
#include "prio-queue.h"
#include "utf8.h"
@@ -29,6 +26,7 @@
#include "progress.h"
#include "origin.h"
#include "commit-fake.h"
+#include "scoreboard.h"
static char blame_usage[] = N_("git blame [<options>] [<rev-opts>] [<rev>] [--] <file>");
@@ -62,19 +60,8 @@ static struct string_list mailmap = STRING_LIST_INIT_NODUP;
#define DEBUG 0
#endif
-#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)
@@ -85,149 +72,6 @@ struct progress_info {
int blamed_lines;
};
-static int diff_hunks(mmfile_t *file_a, mmfile_t *file_b,
- xdl_emit_hunk_consume_func_t hunk_func, void *cb_data, int xdl_opts)
-{
- xpparam_t xpp = {0};
- xdemitconf_t xecfg = {0};
- xdemitcb_t ecb = {NULL};
-
- xpp.flags = xdl_opts;
- xecfg.hunk_func = hunk_func;
- ecb.priv = cb_data;
- return xdi_diff(file_a, file_b, &xpp, &xecfg, &ecb);
-}
-
-/*
- * 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, int *num_read_blob)
-{
- 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_oid, 1, &file->ptr, &file_size))
- ;
- else
- file->ptr = read_sha1_file(o->blob_oid.hash, &type,
- &file_size);
- file->size = file_size;
-
- if (!file->ptr)
- die("Cannot read blob %s for path %s",
- oid_to_hex(&o->blob_oid),
- o->path);
- o->file = *file;
- }
- else
- *file = o->file;
-}
-
-static void drop_origin_blob(struct origin *o)
-{
- if (o->file.ptr) {
- free(o->file.ptr);
- o->file.ptr = NULL;
- }
-}
-
-/*
- * 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)
@@ -236,111 +80,6 @@ static int compare_commits_by_reverse_commit_date(const void *a,
}
/*
- * 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;
-
- /*
- * blame for a blame_entry with score lower than these thresholds
- * is not passed to the parent using move/copy logic.
- */
- unsigned blame_move_score;
- unsigned blame_copy_score;
-
- /* stats */
- int num_read_blob;
- int num_get_patch;
- int num_commits;
-
- /* options */
- int show_root;
- int reverse;
- int xdl_opts;
- int no_whole_file_rename;
-
- /* callbacks */
- void(*sanity_check)(struct scoreboard *);
- void(*found_guilty_entry)(struct blame_entry *, void *);
-
- void *found_guilty_entry_data;
-};
-
-static void blame_sort_final(struct scoreboard *sb)
-{
- sb->ent = blame_sort(sb->ent, compare_blame_final);
-}
-
-/*
- * 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 (sb->sanity_check) /* sanity */
- sb->sanity_check(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);
- }
-}
-
-/*
* 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
@@ -366,1039 +105,12 @@ static int fill_blob_sha1_and_mode(struct origin *origin)
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(parent, origin->path);
- oidcpy(&porigin->blob_oid, &origin->blob_oid);
- 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(parent, origin->path);
- oidcpy(&porigin->blob_oid, &p->one->oid);
- porigin->mode = p->one->mode;
- break;
- case 'A':
- case 'T':
- /* Did not exist in parent, or type changed */
- break;
- }
- }
- diff_flush(&diff_opts);
- clear_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(parent, p->one->path);
- oidcpy(&porigin->blob_oid, &p->one->oid);
- porigin->mode = p->one->mode;
- break;
- }
- }
- diff_flush(&diff_opts);
- clear_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,
- const struct blame_entry *src)
-{
- struct blame_entry *e = xmalloc(sizeof(*e));
- memcpy(e, src, sizeof(*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)
-{
- 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 */
- add_blame_entry(unblamed, &split[2]);
-
- /* ... and the middle part -- parent */
- add_blame_entry(blamed, &split[1]);
- }
- 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]);
- add_blame_entry(blamed, &split[1]);
- }
- else {
- /* parent and then me */
- dup_entry(blamed, e, &split[1]);
- add_blame_entry(unblamed, &split[2]);
- }
-}
-
-/*
- * 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, &sb->num_read_blob);
- fill_origin_blob(&sb->revs->diffopt, target, &file_o, &sb->num_read_blob);
- sb->num_get_patch++;
-
- if (diff_hunks(&file_p, &file_o, blame_chunk_cb, &d, sb->xdl_opts))
- 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, handle_split_cb, &d, sb->xdl_opts))
- 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, &sb->num_read_blob);
- if (!file_p.ptr)
- return;
-
- /* 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 &&
- sb->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, sb->blame_move_score);
- } while (unblamed);
- target->suspects = reverse_blame(leftover, NULL);
-}
-
-struct blame_list {
- struct blame_entry *ent;
- struct blame_entry split[3];
-};
-
-/*
- * 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(parent, p->one->path);
- oidcpy(&norigin->blob_oid, &p->one->oid);
- norigin->mode = p->one->mode;
- fill_origin_blob(&sb->revs->diffopt, norigin, &file_p, &sb->num_read_blob);
- 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 &&
- sb->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, sb->blame_copy_score);
- } while (unblamed);
- target->suspects = reverse_blame(leftover, NULL);
- diff_flush(&diff_opts);
- clear_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,
- int reverse)
-{
- 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, int reverse)
-{
- struct commit_list *l = first_scapegoat(revs, commit, reverse);
- 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)
-{
- 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, sb->reverse);
- 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 - sb->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, sb->reverse);
- 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 (!oidcmp(&porigin->blob_oid, &origin->blob_oid)) {
- pass_whole_blame(sb, origin, porigin);
- origin_decref(porigin);
- goto finish;
- }
- for (j = same = 0; j < i; j++)
- if (sg_origin[j] &&
- !oidcmp(&sg_origin[j]->blob_oid, &porigin->blob_oid)) {
- same = 1;
- break;
- }
- if (!same)
- sg_origin[i] = porigin;
- else
- origin_decref(porigin);
- }
- }
-
- sb->num_commits++;
- for (i = 0, sg = first_scapegoat(revs, commit, sb->reverse);
- 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, sb->blame_move_score);
- if (origin->suspects) {
- for (i = 0, sg = first_scapegoat(revs, commit, sb->reverse);
- 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 (sb->blame_copy_score > sb->blame_move_score)
- filter_small(sb, &toosmall, &origin->suspects, sb->blame_copy_score);
- else if (sb->blame_copy_score < sb->blame_move_score) {
- origin->suspects = blame_merge(origin->suspects, toosmall);
- toosmall = NULL;
- filter_small(sb, &toosmall, &origin->suspects, sb->blame_copy_score);
- }
- if (!origin->suspects)
- goto finish;
-
- for (i = 0, sg = first_scapegoat(revs, commit, sb->reverse);
- 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);
-}
-
-/*
* Information on commits, used for output.
*/
struct commit_info {
@@ -1607,74 +319,6 @@ static void found_guilty_entry(struct blame_entry *ent, void *data)
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);
-
- 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 (sb->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 && !sb->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;
- if (sb->found_guilty_entry)
- sb->found_guilty_entry(ent, sb->found_guilty_entry_data);
- if (next) {
- ent = next;
- continue;
- }
- ent->next = sb->ent;
- sb->ent = suspect->suspects;
- suspect->suspects = NULL;
- break;
- }
- }
- origin_decref(suspect);
-
- if (sb->sanity_check) /* sanity */
- sb->sanity_check(sb);
- }
-}
-
static const char *format_time(unsigned long time, const char *tz_str,
int show_raw_time)
{
diff --git a/scoreboard.c b/scoreboard.c
new file mode 100644
index 0000000..0463688
--- /dev/null
+++ b/scoreboard.c
@@ -0,0 +1,1296 @@
+#include "mergesort.h"
+#include "diff.h"
+#include "diffcore.h"
+#include "scoreboard.h"
+
+static int diff_hunks(mmfile_t *file_a, mmfile_t *file_b,
+ xdl_emit_hunk_consume_func_t hunk_func, void *cb_data, int xdl_opts)
+{
+ xpparam_t xpp = {0};
+ xdemitconf_t xecfg = {0};
+ xdemitcb_t ecb = {NULL};
+
+ xpp.flags = xdl_opts;
+ xecfg.hunk_func = hunk_func;
+ ecb.priv = cb_data;
+ return xdi_diff(file_a, file_b, &xpp, &xecfg, &ecb);
+}
+
+/*
+ * 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, int *num_read_blob)
+{
+ 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_oid, 1, &file->ptr, &file_size))
+ ;
+ else
+ file->ptr = read_sha1_file(o->blob_oid.hash, &type,
+ &file_size);
+ file->size = file_size;
+
+ if (!file->ptr)
+ die("Cannot read blob %s for path %s",
+ oid_to_hex(&o->blob_oid),
+ o->path);
+ o->file = *file;
+ }
+ else
+ *file = o->file;
+}
+
+static void drop_origin_blob(struct origin *o)
+{
+ if (o->file.ptr) {
+ free(o->file.ptr);
+ o->file.ptr = NULL;
+ }
+}
+
+/*
+ * 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);
+}
+
+void blame_sort_final(struct scoreboard *sb)
+{
+ sb->ent = blame_sort(sb->ent, compare_blame_final);
+}
+
+/*
+ * 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.
+ */
+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 (sb->sanity_check) /* sanity */
+ sb->sanity_check(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);
+ }
+}
+
+/*
+ * 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(parent, origin->path);
+ oidcpy(&porigin->blob_oid, &origin->blob_oid);
+ 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(parent, origin->path);
+ oidcpy(&porigin->blob_oid, &p->one->oid);
+ porigin->mode = p->one->mode;
+ break;
+ case 'A':
+ case 'T':
+ /* Did not exist in parent, or type changed */
+ break;
+ }
+ }
+ diff_flush(&diff_opts);
+ clear_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(parent, p->one->path);
+ oidcpy(&porigin->blob_oid, &p->one->oid);
+ porigin->mode = p->one->mode;
+ break;
+ }
+ }
+ diff_flush(&diff_opts);
+ clear_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,
+ const struct blame_entry *src)
+{
+ struct blame_entry *e = xmalloc(sizeof(*e));
+ memcpy(e, src, sizeof(*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;
+}
+
+const char *nth_line(struct scoreboard *sb, long lno)
+{
+ return sb->final_buf + sb->lineno[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)
+{
+ 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 */
+ add_blame_entry(unblamed, &split[2]);
+
+ /* ... and the middle part -- parent */
+ add_blame_entry(blamed, &split[1]);
+ }
+ 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]);
+ add_blame_entry(blamed, &split[1]);
+ }
+ else {
+ /* parent and then me */
+ dup_entry(blamed, e, &split[1]);
+ add_blame_entry(unblamed, &split[2]);
+ }
+}
+
+/*
+ * 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, &sb->num_read_blob);
+ fill_origin_blob(&sb->revs->diffopt, target, &file_o, &sb->num_read_blob);
+ sb->num_get_patch++;
+
+ if (diff_hunks(&file_p, &file_o, blame_chunk_cb, &d, sb->xdl_opts))
+ 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.
+ */
+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, handle_split_cb, &d, sb->xdl_opts))
+ 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, &sb->num_read_blob);
+ if (!file_p.ptr)
+ return;
+
+ /* 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 &&
+ sb->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, sb->blame_move_score);
+ } while (unblamed);
+ target->suspects = reverse_blame(leftover, NULL);
+}
+
+struct blame_list {
+ struct blame_entry *ent;
+ struct blame_entry split[3];
+};
+
+/*
+ * 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(parent, p->one->path);
+ oidcpy(&norigin->blob_oid, &p->one->oid);
+ norigin->mode = p->one->mode;
+ fill_origin_blob(&sb->revs->diffopt, norigin, &file_p, &sb->num_read_blob);
+ 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 &&
+ sb->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, sb->blame_copy_score);
+ } while (unblamed);
+ target->suspects = reverse_blame(leftover, NULL);
+ diff_flush(&diff_opts);
+ clear_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,
+ int reverse)
+{
+ 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, int reverse)
+{
+ struct commit_list *l = first_scapegoat(revs, commit, reverse);
+ 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)
+{
+ 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, sb->reverse);
+ 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 - sb->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, sb->reverse);
+ 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 (!oidcmp(&porigin->blob_oid, &origin->blob_oid)) {
+ pass_whole_blame(sb, origin, porigin);
+ origin_decref(porigin);
+ goto finish;
+ }
+ for (j = same = 0; j < i; j++)
+ if (sg_origin[j] &&
+ !oidcmp(&sg_origin[j]->blob_oid, &porigin->blob_oid)) {
+ same = 1;
+ break;
+ }
+ if (!same)
+ sg_origin[i] = porigin;
+ else
+ origin_decref(porigin);
+ }
+ }
+
+ sb->num_commits++;
+ for (i = 0, sg = first_scapegoat(revs, commit, sb->reverse);
+ 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, sb->blame_move_score);
+ if (origin->suspects) {
+ for (i = 0, sg = first_scapegoat(revs, commit, sb->reverse);
+ 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 (sb->blame_copy_score > sb->blame_move_score)
+ filter_small(sb, &toosmall, &origin->suspects, sb->blame_copy_score);
+ else if (sb->blame_copy_score < sb->blame_move_score) {
+ origin->suspects = blame_merge(origin->suspects, toosmall);
+ toosmall = NULL;
+ filter_small(sb, &toosmall, &origin->suspects, sb->blame_copy_score);
+ }
+ if (!origin->suspects)
+ goto finish;
+
+ for (i = 0, sg = first_scapegoat(revs, commit, sb->reverse);
+ 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);
+}
+
+/*
+ * 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. */
+void assign_blame(struct scoreboard *sb, int opt)
+{
+ struct rev_info *revs = sb->revs;
+ struct commit *commit = prio_queue_get(&sb->commits);
+
+ 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 (sb->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 && !sb->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;
+ if (sb->found_guilty_entry)
+ sb->found_guilty_entry(ent, sb->found_guilty_entry_data);
+ if (next) {
+ ent = next;
+ continue;
+ }
+ ent->next = sb->ent;
+ sb->ent = suspect->suspects;
+ suspect->suspects = NULL;
+ break;
+ }
+ }
+ origin_decref(suspect);
+
+ if (sb->sanity_check) /* sanity */
+ sb->sanity_check(sb);
+ }
+}
diff --git a/scoreboard.h b/scoreboard.h
new file mode 100644
index 0000000..7e9e313
--- /dev/null
+++ b/scoreboard.h
@@ -0,0 +1,74 @@
+#ifndef SCOREBOARD_H
+#define SCOREBOARD_H
+
+#include "commit.h"
+#include "revision.h"
+#include "prio-queue.h"
+#include "origin.h"
+
+#define PICKAXE_BLAME_MOVE 01
+#define PICKAXE_BLAME_COPY 02
+#define PICKAXE_BLAME_COPY_HARDER 04
+#define PICKAXE_BLAME_COPY_HARDEST 010
+
+#define BLAME_DEFAULT_MOVE_SCORE 20
+#define BLAME_DEFAULT_COPY_SCORE 40
+
+/*
+ * 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;
+
+ /*
+ * blame for a blame_entry with score lower than these thresholds
+ * is not passed to the parent using move/copy logic.
+ */
+ unsigned blame_move_score;
+ unsigned blame_copy_score;
+
+ /* stats */
+ int num_read_blob;
+ int num_get_patch;
+ int num_commits;
+
+ /* options */
+ int show_root;
+ int reverse;
+ int xdl_opts;
+ int no_whole_file_rename;
+
+ /* callbacks */
+ void(*sanity_check)(struct scoreboard *);
+ void(*found_guilty_entry)(struct blame_entry *, void *);
+
+ void *found_guilty_entry_data;
+};
+
+void coalesce(struct scoreboard *sb);
+void blame_sort_final(struct scoreboard *sb);
+unsigned ent_score(struct scoreboard *sb, struct blame_entry *e);
+void assign_blame(struct scoreboard *sb, int opt);
+const char *nth_line(struct scoreboard *sb, long lno);
+
+#endif /* SCOREBOARD_H */
--
2.9.3