void git_blame__like_git(git_blame *blame, uint32_t opt)
{
while (true) {
git_blame__entry *ent;
git_blame__origin *suspect = NULL;
/* Find a suspect to break down */
for (ent = blame->ent; !suspect && ent; ent = ent->next)
if (!ent->guilty)
suspect = ent->suspect;
if (!suspect)
return; /* all done */
/* We'll use this suspect later in the loop, so hold on to it for now. */
origin_incref(suspect);
pass_blame(blame, suspect, opt);
/* Take responsibility for the remaining entries */
for (ent = blame->ent; ent; ent = ent->next) {
if (same_suspect(ent->suspect, suspect)) {
ent->guilty = true;
ent->is_boundary = !git_oid_cmp(
git_commit_id(suspect->commit),
&blame->options.oldest_commit);
}
}
origin_decref(suspect);
}
coalesce(blame);
}
static void origin_decref(git_blame__origin *o)
{
if (o && --o->refcnt <= 0) {
if (o->previous)
origin_decref(o->previous);
git_blob_free(o->blob);
git_commit_free(o->commit);
git__free(o);
}
}
/*
* src typically is on-stack; we want to copy the information in it to
* a malloced blame_entry that is already on the linked list of the scoreboard.
* The origin of dst loses a refcnt while the origin of src gains one.
*/
static void dup_entry(git_blame__entry *dst, git_blame__entry *src)
{
git_blame__entry *p, *n;
p = dst->prev;
n = dst->next;
origin_incref(src->suspect);
origin_decref(dst->suspect);
memcpy(dst, src, sizeof(*src));
dst->prev = p;
dst->next = n;
dst->score = 0;
}
/*
* 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(git_blame *blame,
git_blame__origin *origin, git_blame__origin *porigin)
{
git_blame__entry *e;
if (!porigin->blob)
git_object_lookup((git_object**)&porigin->blob, blame->repository,
git_blob_id(origin->blob), GIT_OBJ_BLOB);
for (e=blame->ent; e; e=e->next) {
if (!same_suspect(e->suspect, origin))
continue;
origin_incref(porigin);
origin_decref(e->suspect);
e->suspect = porigin;
}
}
/* Given a commit and a path in it, create a new origin structure. */
static int make_origin(git_blame__origin **out, git_commit *commit, const char *path)
{
int error = 0;
git_blame__origin *o;
o = (git_blame__origin *) git__calloc(1, sizeof(*o) + strlen(path) + 1);
GITERR_CHECK_ALLOC(o);
o->commit = commit;
o->refcnt = 1;
strcpy(o->path, path);
if (!(error = git_object_lookup_bypath((git_object**)&o->blob, (git_object*)commit,
path, GIT_OBJ_BLOB))) {
*out = o;
} else {
origin_decref(o);
}
return error;
}
/*
* 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(git_blame *blame)
{
git_blame__entry *ent, *next;
for (ent=blame->ent; ent && (next = ent->next); ent = next) {
if (same_suspect(ent->suspect, next->suspect) &&
ent->guilty == next->guilty &&
ent->s_lno + ent->num_lines == next->s_lno)
{
ent->num_lines += next->num_lines;
ent->next = next->next;
if (ent->next)
ent->next->prev = ent;
origin_decref(next->suspect);
git__free(next);
ent->score = 0;
next = ent; /* again */
}
}
}
/*
* After splitting the blame, the origins used by the on-stack blame_entry
* should lose one refcnt each.
*/
static void decref_split(git_blame__entry *split)
{
int i;
for (i=0; i<3; i++)
origin_decref(split[i].suspect);
}
void git_blame__free_entry(git_blame__entry *ent)
{
if (!ent) return;
origin_decref(ent->suspect);
git__free(ent);
}
static void pass_blame(git_blame *blame, git_blame__origin *origin, uint32_t opt)
{
git_commit *commit = origin->commit;
int i, num_parents;
git_blame__origin *sg_buf[16];
git_blame__origin *porigin, **sg_origin = sg_buf;
num_parents = git_commit_parentcount(commit);
if (!git_oid_cmp(git_commit_id(commit), &blame->options.oldest_commit))
/* Stop at oldest specified commit */
num_parents = 0;
else if (opt & GIT_BLAME_FIRST_PARENT && num_parents > 1)
/* Limit search to the first parent */
num_parents = 1;
if (!num_parents) {
git_oid_cpy(&blame->options.oldest_commit, git_commit_id(commit));
goto finish;
}
else if (num_parents < (int)ARRAY_SIZE(sg_buf))
memset(sg_buf, 0, sizeof(sg_buf));
else
sg_origin = (git_blame__origin **) git__calloc(num_parents, sizeof(*sg_origin));
for (i=0; i<num_parents; i++) {
git_commit *p;
int j, same;
if (sg_origin[i])
continue;
git_commit_parent(&p, origin->commit, i);
porigin = find_origin(blame, p, origin);
if (!porigin)
continue;
if (porigin->blob && origin->blob &&
!git_oid_cmp(git_blob_id(porigin->blob), git_blob_id(origin->blob))) {
pass_whole_blame(blame, origin, porigin);
origin_decref(porigin);
goto finish;
}
for (j = same = 0; j<i; j++)
if (sg_origin[j] &&
!git_oid_cmp(git_blob_id(sg_origin[j]->blob), git_blob_id(porigin->blob))) {
same = 1;
break;
}
if (!same)
sg_origin[i] = porigin;
else
origin_decref(porigin);
}
/* Standard blame */
for (i=0; i<num_parents; i++) {
git_blame__origin *porigin = sg_origin[i];
if (!porigin)
continue;
if (!origin->previous) {
origin_incref(porigin);
origin->previous = porigin;
}
if (pass_blame_to_parent(blame, origin, porigin))
goto finish;
}
/* TODO: optionally find moves in parents' files */
/* TODO: optionally find copies in parents' files */
finish:
for (i=0; i<num_parents; i++)
if (sg_origin[i])
origin_decref(sg_origin[i]);
if (sg_origin != sg_buf)
git__free(sg_origin);
return;
}
