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1d028dc682
This algorithm will replace the heuristic used to identify lines from
ignored commits with one that finds likely candidate lines in the
parent's version of the file. The actual replacement occurs in an
upcoming commit.
The old heuristic simply assigned lines in the target to the same line
number (plus offset) in the parent. The new function uses a
fingerprinting algorithm to detect similarity between lines.
The new heuristic is designed to accurately match changes made
mechanically by formatting tools such as clang-format and clang-tidy.
These tools make changes such as breaking up lines to fit within a
character limit or changing identifiers to fit with a naming convention.
The heuristic is not intended to match more extensive refactoring
changes and may give misleading results in such cases.
In most cases formatting tools preserve line ordering, so the heuristic
is optimised for such cases. (Some types of changes do reorder lines
e.g. sorting keep the line content identical, the git blame -M option
can already be used to address this). The reason that it is advantageous
to rely on ordering is due to source code repeating the same character
sequences often e.g. declaring an identifier on one line and using that
identifier on several subsequent lines. This means that lines can look
very similar to each other which presents a problem when doing fuzzy
matching. Relying on ordering gives us extra clues to point towards the
true match.
The heuristic operates on a single diff chunk change at a time. It
creates a “fingerprint” for each line on each side of the change.
Fingerprints are described in detail in the comment for `struct
fingerprint`, but essentially are a multiset of the character pairs in a
line. The heuristic first identifies the line in the target entry whose
fingerprint is most clearly matched to a line fingerprint in the parent
entry. Where fingerprints match identically, the position of the lines
is used as a tie-break. The heuristic locks in the best match, and
subtracts the fingerprint of the line in the target entry from the
fingerprint of the line in the parent entry to prevent other lines being
matched on the same parts of that line. It then repeats the process
recursively on the section of the chunk before the match, and then the
section of the chunk after the match.
Here's an example of the difference the fingerprinting makes. Consider
a file with two commits:
commit-a 1) void func_1(void *x, void *y);
commit-b 2) void func_2(void *x, void *y);
After a commit 'X', we have:
commit-X 1) void func_1(void *x,
commit-X 2) void *y);
commit-X 3) void func_2(void *x,
commit-X 4) void *y);
When we blame-ignored with the old algorithm, we get:
commit-a 1) void func_1(void *x,
commit-b 2) void *y);
commit-X 3) void func_2(void *x,
commit-X 4) void *y);
Where commit-b is blamed for 2 instead of 3. With the fingerprint
algorithm, we get:
commit-a 1) void func_1(void *x,
commit-a 2) void *y);
commit-b 3) void func_2(void *x,
commit-b 4) void *y);
Note line 2 could be matched with either commit-a or commit-b as it is
equally similar to both lines, but is matched with commit-a because its
position as a fraction of the new line range is more similar to commit-a
as a fraction of the old line range. Line 4 is also equally similar to
both lines, but as it appears after line 3 which will be matched first
it cannot be matched with an earlier line.
For many more examples, see t/t8014-blame-ignore-fuzzy.sh which contains
example parent and target files and the line numbers in the parent that
must be matched.
Signed-off-by: Michael Platings <michael@platin.gs>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2758 lines
79 KiB
C
2758 lines
79 KiB
C
#include "cache.h"
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#include "refs.h"
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#include "object-store.h"
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#include "cache-tree.h"
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#include "mergesort.h"
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#include "diff.h"
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#include "diffcore.h"
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#include "tag.h"
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#include "blame.h"
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#include "alloc.h"
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#include "commit-slab.h"
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define_commit_slab(blame_suspects, struct blame_origin *);
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static struct blame_suspects blame_suspects;
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struct blame_origin *get_blame_suspects(struct commit *commit)
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{
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struct blame_origin **result;
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result = blame_suspects_peek(&blame_suspects, commit);
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return result ? *result : NULL;
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}
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static void set_blame_suspects(struct commit *commit, struct blame_origin *origin)
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{
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*blame_suspects_at(&blame_suspects, commit) = origin;
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}
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void blame_origin_decref(struct blame_origin *o)
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{
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if (o && --o->refcnt <= 0) {
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struct blame_origin *p, *l = NULL;
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if (o->previous)
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blame_origin_decref(o->previous);
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free(o->file.ptr);
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/* Should be present exactly once in commit chain */
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for (p = get_blame_suspects(o->commit); p; l = p, p = p->next) {
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if (p == o) {
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if (l)
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l->next = p->next;
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else
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set_blame_suspects(o->commit, p->next);
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free(o);
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return;
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}
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}
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die("internal error in blame_origin_decref");
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}
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}
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/*
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* Given a commit and a path in it, create a new origin structure.
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* The callers that add blame to the scoreboard should use
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* get_origin() to obtain shared, refcounted copy instead of calling
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* this function directly.
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*/
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static struct blame_origin *make_origin(struct commit *commit, const char *path)
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{
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struct blame_origin *o;
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FLEX_ALLOC_STR(o, path, path);
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o->commit = commit;
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o->refcnt = 1;
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o->next = get_blame_suspects(commit);
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set_blame_suspects(commit, o);
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return o;
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}
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/*
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* Locate an existing origin or create a new one.
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* This moves the origin to front position in the commit util list.
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*/
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static struct blame_origin *get_origin(struct commit *commit, const char *path)
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{
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struct blame_origin *o, *l;
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for (o = get_blame_suspects(commit), l = NULL; o; l = o, o = o->next) {
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if (!strcmp(o->path, path)) {
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/* bump to front */
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if (l) {
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l->next = o->next;
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o->next = get_blame_suspects(commit);
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set_blame_suspects(commit, o);
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}
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return blame_origin_incref(o);
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}
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}
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return make_origin(commit, path);
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}
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static void verify_working_tree_path(struct repository *r,
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struct commit *work_tree, const char *path)
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{
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struct commit_list *parents;
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int pos;
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for (parents = work_tree->parents; parents; parents = parents->next) {
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const struct object_id *commit_oid = &parents->item->object.oid;
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struct object_id blob_oid;
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unsigned mode;
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if (!get_tree_entry(commit_oid, path, &blob_oid, &mode) &&
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oid_object_info(r, &blob_oid, NULL) == OBJ_BLOB)
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return;
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}
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pos = index_name_pos(r->index, path, strlen(path));
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if (pos >= 0)
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; /* path is in the index */
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else if (-1 - pos < r->index->cache_nr &&
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!strcmp(r->index->cache[-1 - pos]->name, path))
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; /* path is in the index, unmerged */
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else
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die("no such path '%s' in HEAD", path);
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}
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static struct commit_list **append_parent(struct repository *r,
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struct commit_list **tail,
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const struct object_id *oid)
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{
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struct commit *parent;
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parent = lookup_commit_reference(r, oid);
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if (!parent)
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die("no such commit %s", oid_to_hex(oid));
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return &commit_list_insert(parent, tail)->next;
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}
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static void append_merge_parents(struct repository *r,
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struct commit_list **tail)
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{
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int merge_head;
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struct strbuf line = STRBUF_INIT;
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merge_head = open(git_path_merge_head(r), O_RDONLY);
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if (merge_head < 0) {
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if (errno == ENOENT)
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return;
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die("cannot open '%s' for reading",
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git_path_merge_head(r));
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}
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while (!strbuf_getwholeline_fd(&line, merge_head, '\n')) {
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struct object_id oid;
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if (line.len < GIT_SHA1_HEXSZ || get_oid_hex(line.buf, &oid))
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die("unknown line in '%s': %s",
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git_path_merge_head(r), line.buf);
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tail = append_parent(r, tail, &oid);
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}
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close(merge_head);
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strbuf_release(&line);
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}
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/*
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* This isn't as simple as passing sb->buf and sb->len, because we
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* want to transfer ownership of the buffer to the commit (so we
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* must use detach).
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*/
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static void set_commit_buffer_from_strbuf(struct repository *r,
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struct commit *c,
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struct strbuf *sb)
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{
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size_t len;
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void *buf = strbuf_detach(sb, &len);
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set_commit_buffer(r, c, buf, len);
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}
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/*
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* Prepare a dummy commit that represents the work tree (or staged) item.
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* Note that annotating work tree item never works in the reverse.
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*/
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static struct commit *fake_working_tree_commit(struct repository *r,
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struct diff_options *opt,
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const char *path,
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const char *contents_from)
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{
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struct commit *commit;
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struct blame_origin *origin;
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struct commit_list **parent_tail, *parent;
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struct object_id head_oid;
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struct strbuf buf = STRBUF_INIT;
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const char *ident;
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time_t now;
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int len;
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struct cache_entry *ce;
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unsigned mode;
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struct strbuf msg = STRBUF_INIT;
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read_index(r->index);
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time(&now);
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commit = alloc_commit_node(r);
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commit->object.parsed = 1;
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commit->date = now;
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parent_tail = &commit->parents;
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if (!resolve_ref_unsafe("HEAD", RESOLVE_REF_READING, &head_oid, NULL))
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die("no such ref: HEAD");
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parent_tail = append_parent(r, parent_tail, &head_oid);
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append_merge_parents(r, parent_tail);
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verify_working_tree_path(r, commit, path);
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origin = make_origin(commit, path);
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ident = fmt_ident("Not Committed Yet", "not.committed.yet", NULL, 0);
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strbuf_addstr(&msg, "tree 0000000000000000000000000000000000000000\n");
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for (parent = commit->parents; parent; parent = parent->next)
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strbuf_addf(&msg, "parent %s\n",
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oid_to_hex(&parent->item->object.oid));
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strbuf_addf(&msg,
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"author %s\n"
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"committer %s\n\n"
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"Version of %s from %s\n",
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ident, ident, path,
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(!contents_from ? path :
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(!strcmp(contents_from, "-") ? "standard input" : contents_from)));
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set_commit_buffer_from_strbuf(r, commit, &msg);
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if (!contents_from || strcmp("-", contents_from)) {
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struct stat st;
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const char *read_from;
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char *buf_ptr;
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unsigned long buf_len;
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if (contents_from) {
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if (stat(contents_from, &st) < 0)
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die_errno("Cannot stat '%s'", contents_from);
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read_from = contents_from;
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}
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else {
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if (lstat(path, &st) < 0)
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die_errno("Cannot lstat '%s'", path);
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read_from = path;
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}
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mode = canon_mode(st.st_mode);
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switch (st.st_mode & S_IFMT) {
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case S_IFREG:
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if (opt->flags.allow_textconv &&
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textconv_object(r, read_from, mode, &null_oid, 0, &buf_ptr, &buf_len))
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strbuf_attach(&buf, buf_ptr, buf_len, buf_len + 1);
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else if (strbuf_read_file(&buf, read_from, st.st_size) != st.st_size)
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die_errno("cannot open or read '%s'", read_from);
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break;
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case S_IFLNK:
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if (strbuf_readlink(&buf, read_from, st.st_size) < 0)
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die_errno("cannot readlink '%s'", read_from);
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break;
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default:
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die("unsupported file type %s", read_from);
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}
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}
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else {
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/* Reading from stdin */
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mode = 0;
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if (strbuf_read(&buf, 0, 0) < 0)
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die_errno("failed to read from stdin");
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}
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convert_to_git(r->index, path, buf.buf, buf.len, &buf, 0);
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origin->file.ptr = buf.buf;
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origin->file.size = buf.len;
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pretend_object_file(buf.buf, buf.len, OBJ_BLOB, &origin->blob_oid);
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/*
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* Read the current index, replace the path entry with
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* origin->blob_sha1 without mucking with its mode or type
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* bits; we are not going to write this index out -- we just
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* want to run "diff-index --cached".
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*/
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discard_index(r->index);
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read_index(r->index);
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len = strlen(path);
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if (!mode) {
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int pos = index_name_pos(r->index, path, len);
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if (0 <= pos)
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mode = r->index->cache[pos]->ce_mode;
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else
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/* Let's not bother reading from HEAD tree */
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mode = S_IFREG | 0644;
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}
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ce = make_empty_cache_entry(r->index, len);
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oidcpy(&ce->oid, &origin->blob_oid);
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memcpy(ce->name, path, len);
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ce->ce_flags = create_ce_flags(0);
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ce->ce_namelen = len;
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ce->ce_mode = create_ce_mode(mode);
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add_index_entry(r->index, ce,
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ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE);
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cache_tree_invalidate_path(r->index, path);
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return commit;
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}
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static int diff_hunks(mmfile_t *file_a, mmfile_t *file_b,
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xdl_emit_hunk_consume_func_t hunk_func, void *cb_data, int xdl_opts)
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{
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xpparam_t xpp = {0};
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xdemitconf_t xecfg = {0};
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xdemitcb_t ecb = {NULL};
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xpp.flags = xdl_opts;
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xecfg.hunk_func = hunk_func;
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ecb.priv = cb_data;
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return xdi_diff(file_a, file_b, &xpp, &xecfg, &ecb);
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}
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static const char *get_next_line(const char *start, const char *end)
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{
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const char *nl = memchr(start, '\n', end - start);
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return nl ? nl + 1 : end;
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}
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static int find_line_starts(int **line_starts, const char *buf,
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unsigned long len)
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{
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const char *end = buf + len;
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const char *p;
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int *lineno;
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int num = 0;
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for (p = buf; p < end; p = get_next_line(p, end))
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num++;
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ALLOC_ARRAY(*line_starts, num + 1);
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lineno = *line_starts;
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for (p = buf; p < end; p = get_next_line(p, end))
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*lineno++ = p - buf;
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*lineno = len;
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return num;
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}
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struct fingerprint_entry;
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/* A fingerprint is intended to loosely represent a string, such that two
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* fingerprints can be quickly compared to give an indication of the similarity
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* of the strings that they represent.
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*
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* A fingerprint is represented as a multiset of the lower-cased byte pairs in
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* the string that it represents. Whitespace is added at each end of the
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* string. Whitespace pairs are ignored. Whitespace is converted to '\0'.
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* For example, the string "Darth Radar" will be converted to the following
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* fingerprint:
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* {"\0d", "da", "da", "ar", "ar", "rt", "th", "h\0", "\0r", "ra", "ad", "r\0"}
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*
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* The similarity between two fingerprints is the size of the intersection of
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* their multisets, including repeated elements. See fingerprint_similarity for
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* examples.
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*
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* For ease of implementation, the fingerprint is implemented as a map
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* of byte pairs to the count of that byte pair in the string, instead of
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* allowing repeated elements in a set.
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*/
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struct fingerprint {
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struct hashmap map;
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/* As we know the maximum number of entries in advance, it's
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* convenient to store the entries in a single array instead of having
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* the hashmap manage the memory.
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*/
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struct fingerprint_entry *entries;
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};
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|
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/* A byte pair in a fingerprint. Stores the number of times the byte pair
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* occurs in the string that the fingerprint represents.
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*/
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struct fingerprint_entry {
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/* The hashmap entry - the hash represents the byte pair in its
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* entirety so we don't need to store the byte pair separately.
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*/
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struct hashmap_entry entry;
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/* The number of times the byte pair occurs in the string that the
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* fingerprint represents.
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*/
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int count;
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};
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|
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/* See `struct fingerprint` for an explanation of what a fingerprint is.
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* \param result the fingerprint of the string is stored here. This must be
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* freed later using free_fingerprint.
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* \param line_begin the start of the string
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* \param line_end the end of the string
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*/
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static void get_fingerprint(struct fingerprint *result,
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const char *line_begin,
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const char *line_end)
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{
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unsigned int hash, c0 = 0, c1;
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const char *p;
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int max_map_entry_count = 1 + line_end - line_begin;
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struct fingerprint_entry *entry = xcalloc(max_map_entry_count,
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sizeof(struct fingerprint_entry));
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struct fingerprint_entry *found_entry;
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|
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hashmap_init(&result->map, NULL, NULL, max_map_entry_count);
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result->entries = entry;
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for (p = line_begin; p <= line_end; ++p, c0 = c1) {
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/* Always terminate the string with whitespace.
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* Normalise whitespace to 0, and normalise letters to
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* lower case. This won't work for multibyte characters but at
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* worst will match some unrelated characters.
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*/
|
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if ((p == line_end) || isspace(*p))
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c1 = 0;
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else
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c1 = tolower(*p);
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hash = c0 | (c1 << 8);
|
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/* Ignore whitespace pairs */
|
|
if (hash == 0)
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continue;
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hashmap_entry_init(entry, hash);
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|
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found_entry = hashmap_get(&result->map, entry, NULL);
|
|
if (found_entry) {
|
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found_entry->count += 1;
|
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} else {
|
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entry->count = 1;
|
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hashmap_add(&result->map, entry);
|
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++entry;
|
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}
|
|
}
|
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}
|
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|
|
static void free_fingerprint(struct fingerprint *f)
|
|
{
|
|
hashmap_free(&f->map, 0);
|
|
free(f->entries);
|
|
}
|
|
|
|
/* Calculates the similarity between two fingerprints as the size of the
|
|
* intersection of their multisets, including repeated elements. See
|
|
* `struct fingerprint` for an explanation of the fingerprint representation.
|
|
* The similarity between "cat mat" and "father rather" is 2 because "at" is
|
|
* present twice in both strings while the similarity between "tim" and "mit"
|
|
* is 0.
|
|
*/
|
|
static int fingerprint_similarity(struct fingerprint *a, struct fingerprint *b)
|
|
{
|
|
int intersection = 0;
|
|
struct hashmap_iter iter;
|
|
const struct fingerprint_entry *entry_a, *entry_b;
|
|
|
|
hashmap_iter_init(&b->map, &iter);
|
|
|
|
while ((entry_b = hashmap_iter_next(&iter))) {
|
|
if ((entry_a = hashmap_get(&a->map, entry_b, NULL))) {
|
|
intersection += entry_a->count < entry_b->count ?
|
|
entry_a->count : entry_b->count;
|
|
}
|
|
}
|
|
return intersection;
|
|
}
|
|
|
|
/* Subtracts byte-pair elements in B from A, modifying A in place.
|
|
*/
|
|
static void fingerprint_subtract(struct fingerprint *a, struct fingerprint *b)
|
|
{
|
|
struct hashmap_iter iter;
|
|
struct fingerprint_entry *entry_a;
|
|
const struct fingerprint_entry *entry_b;
|
|
|
|
hashmap_iter_init(&b->map, &iter);
|
|
|
|
while ((entry_b = hashmap_iter_next(&iter))) {
|
|
if ((entry_a = hashmap_get(&a->map, entry_b, NULL))) {
|
|
if (entry_a->count <= entry_b->count)
|
|
hashmap_remove(&a->map, entry_b, NULL);
|
|
else
|
|
entry_a->count -= entry_b->count;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Calculate fingerprints for a series of lines.
|
|
* Puts the fingerprints in the fingerprints array, which must have been
|
|
* preallocated to allow storing line_count elements.
|
|
*/
|
|
static void get_line_fingerprints(struct fingerprint *fingerprints,
|
|
const char *content, const int *line_starts,
|
|
long first_line, long line_count)
|
|
{
|
|
int i;
|
|
const char *linestart, *lineend;
|
|
|
|
line_starts += first_line;
|
|
for (i = 0; i < line_count; ++i) {
|
|
linestart = content + line_starts[i];
|
|
lineend = content + line_starts[i + 1];
|
|
get_fingerprint(fingerprints + i, linestart, lineend);
|
|
}
|
|
}
|
|
|
|
static void free_line_fingerprints(struct fingerprint *fingerprints,
|
|
int nr_fingerprints)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < nr_fingerprints; i++)
|
|
free_fingerprint(&fingerprints[i]);
|
|
}
|
|
|
|
/* This contains the data necessary to linearly map a line number in one half
|
|
* of a diff chunk to the line in the other half of the diff chunk that is
|
|
* closest in terms of its position as a fraction of the length of the chunk.
|
|
*/
|
|
struct line_number_mapping {
|
|
int destination_start, destination_length,
|
|
source_start, source_length;
|
|
};
|
|
|
|
/* Given a line number in one range, offset and scale it to map it onto the
|
|
* other range.
|
|
* Essentially this mapping is a simple linear equation but the calculation is
|
|
* more complicated to allow performing it with integer operations.
|
|
* Another complication is that if a line could map onto many lines in the
|
|
* destination range then we want to choose the line at the center of those
|
|
* possibilities.
|
|
* Example: if the chunk is 2 lines long in A and 10 lines long in B then the
|
|
* first 5 lines in B will map onto the first line in the A chunk, while the
|
|
* last 5 lines will all map onto the second line in the A chunk.
|
|
* Example: if the chunk is 10 lines long in A and 2 lines long in B then line
|
|
* 0 in B will map onto line 2 in A, and line 1 in B will map onto line 7 in A.
|
|
*/
|
|
static int map_line_number(int line_number,
|
|
const struct line_number_mapping *mapping)
|
|
{
|
|
return ((line_number - mapping->source_start) * 2 + 1) *
|
|
mapping->destination_length /
|
|
(mapping->source_length * 2) +
|
|
mapping->destination_start;
|
|
}
|
|
|
|
/* Get a pointer to the element storing the similarity between a line in A
|
|
* and a line in B.
|
|
*
|
|
* The similarities are stored in a 2-dimensional array. Each "row" in the
|
|
* array contains the similarities for a line in B. The similarities stored in
|
|
* a row are the similarities between the line in B and the nearby lines in A.
|
|
* To keep the length of each row the same, it is padded out with values of -1
|
|
* where the search range extends beyond the lines in A.
|
|
* For example, if max_search_distance_a is 2 and the two sides of a diff chunk
|
|
* look like this:
|
|
* a | m
|
|
* b | n
|
|
* c | o
|
|
* d | p
|
|
* e | q
|
|
* Then the similarity array will contain:
|
|
* [-1, -1, am, bm, cm,
|
|
* -1, an, bn, cn, dn,
|
|
* ao, bo, co, do, eo,
|
|
* bp, cp, dp, ep, -1,
|
|
* cq, dq, eq, -1, -1]
|
|
* Where similarities are denoted either by -1 for invalid, or the
|
|
* concatenation of the two lines in the diff being compared.
|
|
*
|
|
* \param similarities array of similarities between lines in A and B
|
|
* \param line_a the index of the line in A, in the same frame of reference as
|
|
* closest_line_a.
|
|
* \param local_line_b the index of the line in B, relative to the first line
|
|
* in B that similarities represents.
|
|
* \param closest_line_a the index of the line in A that is deemed to be
|
|
* closest to local_line_b. This must be in the same
|
|
* frame of reference as line_a. This value defines
|
|
* where similarities is centered for the line in B.
|
|
* \param max_search_distance_a maximum distance in lines from the closest line
|
|
* in A for other lines in A for which
|
|
* similarities may be calculated.
|
|
*/
|
|
static int *get_similarity(int *similarities,
|
|
int line_a, int local_line_b,
|
|
int closest_line_a, int max_search_distance_a)
|
|
{
|
|
assert(abs(line_a - closest_line_a) <=
|
|
max_search_distance_a);
|
|
return similarities + line_a - closest_line_a +
|
|
max_search_distance_a +
|
|
local_line_b * (max_search_distance_a * 2 + 1);
|
|
}
|
|
|
|
#define CERTAIN_NOTHING_MATCHES -2
|
|
#define CERTAINTY_NOT_CALCULATED -1
|
|
|
|
/* Given a line in B, first calculate its similarities with nearby lines in A
|
|
* if not already calculated, then identify the most similar and second most
|
|
* similar lines. The "certainty" is calculated based on those two
|
|
* similarities.
|
|
*
|
|
* \param start_a the index of the first line of the chunk in A
|
|
* \param length_a the length in lines of the chunk in A
|
|
* \param local_line_b the index of the line in B, relative to the first line
|
|
* in the chunk.
|
|
* \param fingerprints_a array of fingerprints for the chunk in A
|
|
* \param fingerprints_b array of fingerprints for the chunk in B
|
|
* \param similarities 2-dimensional array of similarities between lines in A
|
|
* and B. See get_similarity() for more details.
|
|
* \param certainties array of values indicating how strongly a line in B is
|
|
* matched with some line in A.
|
|
* \param second_best_result array of absolute indices in A for the second
|
|
* closest match of a line in B.
|
|
* \param result array of absolute indices in A for the closest match of a line
|
|
* in B.
|
|
* \param max_search_distance_a maximum distance in lines from the closest line
|
|
* in A for other lines in A for which
|
|
* similarities may be calculated.
|
|
* \param map_line_number_in_b_to_a parameter to map_line_number().
|
|
*/
|
|
static void find_best_line_matches(
|
|
int start_a,
|
|
int length_a,
|
|
int start_b,
|
|
int local_line_b,
|
|
struct fingerprint *fingerprints_a,
|
|
struct fingerprint *fingerprints_b,
|
|
int *similarities,
|
|
int *certainties,
|
|
int *second_best_result,
|
|
int *result,
|
|
const int max_search_distance_a,
|
|
const struct line_number_mapping *map_line_number_in_b_to_a)
|
|
{
|
|
|
|
int i, search_start, search_end, closest_local_line_a, *similarity,
|
|
best_similarity = 0, second_best_similarity = 0,
|
|
best_similarity_index = 0, second_best_similarity_index = 0;
|
|
|
|
/* certainty has already been calculated so no need to redo the work */
|
|
if (certainties[local_line_b] != CERTAINTY_NOT_CALCULATED)
|
|
return;
|
|
|
|
closest_local_line_a = map_line_number(
|
|
local_line_b + start_b, map_line_number_in_b_to_a) - start_a;
|
|
|
|
search_start = closest_local_line_a - max_search_distance_a;
|
|
if (search_start < 0)
|
|
search_start = 0;
|
|
|
|
search_end = closest_local_line_a + max_search_distance_a + 1;
|
|
if (search_end > length_a)
|
|
search_end = length_a;
|
|
|
|
for (i = search_start; i < search_end; ++i) {
|
|
similarity = get_similarity(similarities,
|
|
i, local_line_b,
|
|
closest_local_line_a,
|
|
max_search_distance_a);
|
|
if (*similarity == -1) {
|
|
/* This value will never exceed 10 but assert just in
|
|
* case
|
|
*/
|
|
assert(abs(i - closest_local_line_a) < 1000);
|
|
/* scale the similarity by (1000 - distance from
|
|
* closest line) to act as a tie break between lines
|
|
* that otherwise are equally similar.
|
|
*/
|
|
*similarity = fingerprint_similarity(
|
|
fingerprints_b + local_line_b,
|
|
fingerprints_a + i) *
|
|
(1000 - abs(i - closest_local_line_a));
|
|
}
|
|
if (*similarity > best_similarity) {
|
|
second_best_similarity = best_similarity;
|
|
second_best_similarity_index = best_similarity_index;
|
|
best_similarity = *similarity;
|
|
best_similarity_index = i;
|
|
} else if (*similarity > second_best_similarity) {
|
|
second_best_similarity = *similarity;
|
|
second_best_similarity_index = i;
|
|
}
|
|
}
|
|
|
|
if (best_similarity == 0) {
|
|
/* this line definitely doesn't match with anything. Mark it
|
|
* with this special value so it doesn't get invalidated and
|
|
* won't be recalculated.
|
|
*/
|
|
certainties[local_line_b] = CERTAIN_NOTHING_MATCHES;
|
|
result[local_line_b] = -1;
|
|
} else {
|
|
/* Calculate the certainty with which this line matches.
|
|
* If the line matches well with two lines then that reduces
|
|
* the certainty. However we still want to prioritise matching
|
|
* a line that matches very well with two lines over matching a
|
|
* line that matches poorly with one line, hence doubling
|
|
* best_similarity.
|
|
* This means that if we have
|
|
* line X that matches only one line with a score of 3,
|
|
* line Y that matches two lines equally with a score of 5,
|
|
* and line Z that matches only one line with a score or 2,
|
|
* then the lines in order of certainty are X, Y, Z.
|
|
*/
|
|
certainties[local_line_b] = best_similarity * 2 -
|
|
second_best_similarity;
|
|
|
|
/* We keep both the best and second best results to allow us to
|
|
* check at a later stage of the matching process whether the
|
|
* result needs to be invalidated.
|
|
*/
|
|
result[local_line_b] = start_a + best_similarity_index;
|
|
second_best_result[local_line_b] =
|
|
start_a + second_best_similarity_index;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* This finds the line that we can match with the most confidence, and
|
|
* uses it as a partition. It then calls itself on the lines on either side of
|
|
* that partition. In this way we avoid lines appearing out of order, and
|
|
* retain a sensible line ordering.
|
|
* \param start_a index of the first line in A with which lines in B may be
|
|
* compared.
|
|
* \param start_b index of the first line in B for which matching should be
|
|
* done.
|
|
* \param length_a number of lines in A with which lines in B may be compared.
|
|
* \param length_b number of lines in B for which matching should be done.
|
|
* \param fingerprints_a mutable array of fingerprints in A. The first element
|
|
* corresponds to the line at start_a.
|
|
* \param fingerprints_b array of fingerprints in B. The first element
|
|
* corresponds to the line at start_b.
|
|
* \param similarities 2-dimensional array of similarities between lines in A
|
|
* and B. See get_similarity() for more details.
|
|
* \param certainties array of values indicating how strongly a line in B is
|
|
* matched with some line in A.
|
|
* \param second_best_result array of absolute indices in A for the second
|
|
* closest match of a line in B.
|
|
* \param result array of absolute indices in A for the closest match of a line
|
|
* in B.
|
|
* \param max_search_distance_a maximum distance in lines from the closest line
|
|
* in A for other lines in A for which
|
|
* similarities may be calculated.
|
|
* \param max_search_distance_b an upper bound on the greatest possible
|
|
* distance between lines in B such that they will
|
|
* both be compared with the same line in A
|
|
* according to max_search_distance_a.
|
|
* \param map_line_number_in_b_to_a parameter to map_line_number().
|
|
*/
|
|
static void fuzzy_find_matching_lines_recurse(
|
|
int start_a, int start_b,
|
|
int length_a, int length_b,
|
|
struct fingerprint *fingerprints_a,
|
|
struct fingerprint *fingerprints_b,
|
|
int *similarities,
|
|
int *certainties,
|
|
int *second_best_result,
|
|
int *result,
|
|
int max_search_distance_a,
|
|
int max_search_distance_b,
|
|
const struct line_number_mapping *map_line_number_in_b_to_a)
|
|
{
|
|
int i, invalidate_min, invalidate_max, offset_b,
|
|
second_half_start_a, second_half_start_b,
|
|
second_half_length_a, second_half_length_b,
|
|
most_certain_line_a, most_certain_local_line_b = -1,
|
|
most_certain_line_certainty = -1,
|
|
closest_local_line_a;
|
|
|
|
for (i = 0; i < length_b; ++i) {
|
|
find_best_line_matches(start_a,
|
|
length_a,
|
|
start_b,
|
|
i,
|
|
fingerprints_a,
|
|
fingerprints_b,
|
|
similarities,
|
|
certainties,
|
|
second_best_result,
|
|
result,
|
|
max_search_distance_a,
|
|
map_line_number_in_b_to_a);
|
|
|
|
if (certainties[i] > most_certain_line_certainty) {
|
|
most_certain_line_certainty = certainties[i];
|
|
most_certain_local_line_b = i;
|
|
}
|
|
}
|
|
|
|
/* No matches. */
|
|
if (most_certain_local_line_b == -1)
|
|
return;
|
|
|
|
most_certain_line_a = result[most_certain_local_line_b];
|
|
|
|
/*
|
|
* Subtract the most certain line's fingerprint in B from the matched
|
|
* fingerprint in A. This means that other lines in B can't also match
|
|
* the same parts of the line in A.
|
|
*/
|
|
fingerprint_subtract(fingerprints_a + most_certain_line_a - start_a,
|
|
fingerprints_b + most_certain_local_line_b);
|
|
|
|
/* Invalidate results that may be affected by the choice of most
|
|
* certain line.
|
|
*/
|
|
invalidate_min = most_certain_local_line_b - max_search_distance_b;
|
|
invalidate_max = most_certain_local_line_b + max_search_distance_b + 1;
|
|
if (invalidate_min < 0)
|
|
invalidate_min = 0;
|
|
if (invalidate_max > length_b)
|
|
invalidate_max = length_b;
|
|
|
|
/* As the fingerprint in A has changed, discard previously calculated
|
|
* similarity values with that fingerprint.
|
|
*/
|
|
for (i = invalidate_min; i < invalidate_max; ++i) {
|
|
closest_local_line_a = map_line_number(
|
|
i + start_b, map_line_number_in_b_to_a) - start_a;
|
|
|
|
/* Check that the lines in A and B are close enough that there
|
|
* is a similarity value for them.
|
|
*/
|
|
if (abs(most_certain_line_a - start_a - closest_local_line_a) >
|
|
max_search_distance_a) {
|
|
continue;
|
|
}
|
|
|
|
*get_similarity(similarities, most_certain_line_a - start_a,
|
|
i, closest_local_line_a,
|
|
max_search_distance_a) = -1;
|
|
}
|
|
|
|
/* More invalidating of results that may be affected by the choice of
|
|
* most certain line.
|
|
* Discard the matches for lines in B that are currently matched with a
|
|
* line in A such that their ordering contradicts the ordering imposed
|
|
* by the choice of most certain line.
|
|
*/
|
|
for (i = most_certain_local_line_b - 1; i >= invalidate_min; --i) {
|
|
/* In this loop we discard results for lines in B that are
|
|
* before most-certain-line-B but are matched with a line in A
|
|
* that is after most-certain-line-A.
|
|
*/
|
|
if (certainties[i] >= 0 &&
|
|
(result[i] >= most_certain_line_a ||
|
|
second_best_result[i] >= most_certain_line_a)) {
|
|
certainties[i] = CERTAINTY_NOT_CALCULATED;
|
|
}
|
|
}
|
|
for (i = most_certain_local_line_b + 1; i < invalidate_max; ++i) {
|
|
/* In this loop we discard results for lines in B that are
|
|
* after most-certain-line-B but are matched with a line in A
|
|
* that is before most-certain-line-A.
|
|
*/
|
|
if (certainties[i] >= 0 &&
|
|
(result[i] <= most_certain_line_a ||
|
|
second_best_result[i] <= most_certain_line_a)) {
|
|
certainties[i] = CERTAINTY_NOT_CALCULATED;
|
|
}
|
|
}
|
|
|
|
/* Repeat the matching process for lines before the most certain line.
|
|
*/
|
|
if (most_certain_local_line_b > 0) {
|
|
fuzzy_find_matching_lines_recurse(
|
|
start_a, start_b,
|
|
most_certain_line_a + 1 - start_a,
|
|
most_certain_local_line_b,
|
|
fingerprints_a, fingerprints_b, similarities,
|
|
certainties, second_best_result, result,
|
|
max_search_distance_a,
|
|
max_search_distance_b,
|
|
map_line_number_in_b_to_a);
|
|
}
|
|
/* Repeat the matching process for lines after the most certain line.
|
|
*/
|
|
if (most_certain_local_line_b + 1 < length_b) {
|
|
second_half_start_a = most_certain_line_a;
|
|
offset_b = most_certain_local_line_b + 1;
|
|
second_half_start_b = start_b + offset_b;
|
|
second_half_length_a =
|
|
length_a + start_a - second_half_start_a;
|
|
second_half_length_b =
|
|
length_b + start_b - second_half_start_b;
|
|
fuzzy_find_matching_lines_recurse(
|
|
second_half_start_a, second_half_start_b,
|
|
second_half_length_a, second_half_length_b,
|
|
fingerprints_a + second_half_start_a - start_a,
|
|
fingerprints_b + offset_b,
|
|
similarities +
|
|
offset_b * (max_search_distance_a * 2 + 1),
|
|
certainties + offset_b,
|
|
second_best_result + offset_b, result + offset_b,
|
|
max_search_distance_a,
|
|
max_search_distance_b,
|
|
map_line_number_in_b_to_a);
|
|
}
|
|
}
|
|
|
|
/* Find the lines in the parent line range that most closely match the lines in
|
|
* the target line range. This is accomplished by matching fingerprints in each
|
|
* blame_origin, and choosing the best matches that preserve the line ordering.
|
|
* See struct fingerprint for details of fingerprint matching, and
|
|
* fuzzy_find_matching_lines_recurse for details of preserving line ordering.
|
|
*
|
|
* The performance is believed to be O(n log n) in the typical case and O(n^2)
|
|
* in a pathological case, where n is the number of lines in the target range.
|
|
*/
|
|
static int *fuzzy_find_matching_lines(struct blame_origin *parent,
|
|
struct blame_origin *target,
|
|
int tlno, int parent_slno, int same,
|
|
int parent_len)
|
|
{
|
|
/* We use the terminology "A" for the left hand side of the diff AKA
|
|
* parent, and "B" for the right hand side of the diff AKA target. */
|
|
int start_a = parent_slno;
|
|
int length_a = parent_len;
|
|
int start_b = tlno;
|
|
int length_b = same - tlno;
|
|
|
|
struct line_number_mapping map_line_number_in_b_to_a = {
|
|
start_a, length_a, start_b, length_b
|
|
};
|
|
|
|
struct fingerprint *fingerprints_a = parent->fingerprints;
|
|
struct fingerprint *fingerprints_b = target->fingerprints;
|
|
|
|
int i, *result, *second_best_result,
|
|
*certainties, *similarities, similarity_count;
|
|
|
|
/*
|
|
* max_search_distance_a means that given a line in B, compare it to
|
|
* the line in A that is closest to its position, and the lines in A
|
|
* that are no greater than max_search_distance_a lines away from the
|
|
* closest line in A.
|
|
*
|
|
* max_search_distance_b is an upper bound on the greatest possible
|
|
* distance between lines in B such that they will both be compared
|
|
* with the same line in A according to max_search_distance_a.
|
|
*/
|
|
int max_search_distance_a = 10, max_search_distance_b;
|
|
|
|
if (length_a <= 0)
|
|
return NULL;
|
|
|
|
if (max_search_distance_a >= length_a)
|
|
max_search_distance_a = length_a ? length_a - 1 : 0;
|
|
|
|
max_search_distance_b = ((2 * max_search_distance_a + 1) * length_b
|
|
- 1) / length_a;
|
|
|
|
result = xcalloc(sizeof(int), length_b);
|
|
second_best_result = xcalloc(sizeof(int), length_b);
|
|
certainties = xcalloc(sizeof(int), length_b);
|
|
|
|
/* See get_similarity() for details of similarities. */
|
|
similarity_count = length_b * (max_search_distance_a * 2 + 1);
|
|
similarities = xcalloc(sizeof(int), similarity_count);
|
|
|
|
for (i = 0; i < length_b; ++i) {
|
|
result[i] = -1;
|
|
second_best_result[i] = -1;
|
|
certainties[i] = CERTAINTY_NOT_CALCULATED;
|
|
}
|
|
|
|
for (i = 0; i < similarity_count; ++i)
|
|
similarities[i] = -1;
|
|
|
|
fuzzy_find_matching_lines_recurse(start_a, start_b,
|
|
length_a, length_b,
|
|
fingerprints_a + start_a,
|
|
fingerprints_b + start_b,
|
|
similarities,
|
|
certainties,
|
|
second_best_result,
|
|
result,
|
|
max_search_distance_a,
|
|
max_search_distance_b,
|
|
&map_line_number_in_b_to_a);
|
|
|
|
free(similarities);
|
|
free(certainties);
|
|
free(second_best_result);
|
|
|
|
return result;
|
|
}
|
|
|
|
static void fill_origin_fingerprints(struct blame_origin *o, mmfile_t *file)
|
|
{
|
|
int *line_starts;
|
|
|
|
if (o->fingerprints)
|
|
return;
|
|
o->num_lines = find_line_starts(&line_starts, o->file.ptr,
|
|
o->file.size);
|
|
/* TODO: Will fill in fingerprints in a future commit */
|
|
free(line_starts);
|
|
}
|
|
|
|
static void drop_origin_fingerprints(struct blame_origin *o)
|
|
{
|
|
}
|
|
|
|
/*
|
|
* Given an origin, prepare mmfile_t structure to be used by the
|
|
* diff machinery
|
|
*/
|
|
static void fill_origin_blob(struct diff_options *opt,
|
|
struct blame_origin *o, mmfile_t *file,
|
|
int *num_read_blob, int fill_fingerprints)
|
|
{
|
|
if (!o->file.ptr) {
|
|
enum object_type type;
|
|
unsigned long file_size;
|
|
|
|
(*num_read_blob)++;
|
|
if (opt->flags.allow_textconv &&
|
|
textconv_object(opt->repo, o->path, o->mode,
|
|
&o->blob_oid, 1, &file->ptr, &file_size))
|
|
;
|
|
else
|
|
file->ptr = read_object_file(&o->blob_oid, &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;
|
|
if (fill_fingerprints)
|
|
fill_origin_fingerprints(o, file);
|
|
}
|
|
|
|
static void drop_origin_blob(struct blame_origin *o)
|
|
{
|
|
FREE_AND_NULL(o->file.ptr);
|
|
drop_origin_fingerprints(o);
|
|
}
|
|
|
|
/*
|
|
* 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;
|
|
}
|
|
|
|
void blame_sort_final(struct blame_scoreboard *sb)
|
|
{
|
|
sb->ent = llist_mergesort(sb->ent, get_next_blame, set_next_blame,
|
|
compare_blame_final);
|
|
}
|
|
|
|
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);
|
|
}
|
|
|
|
/*
|
|
* For debugging -- origin is refcounted, and this asserts that
|
|
* we do not underflow.
|
|
*/
|
|
static void sanity_check_refcnt(struct blame_scoreboard *sb)
|
|
{
|
|
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)
|
|
sb->on_sanity_fail(sb, baa);
|
|
}
|
|
|
|
/*
|
|
* 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 blame_coalesce(struct blame_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->ignored == next->ignored &&
|
|
ent->unblamable == next->unblamable) {
|
|
ent->num_lines += next->num_lines;
|
|
ent->next = next->next;
|
|
blame_origin_decref(next->suspect);
|
|
free(next);
|
|
ent->score = 0;
|
|
next = ent; /* again */
|
|
}
|
|
}
|
|
|
|
if (sb->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 blame_scoreboard *sb, struct blame_origin *porigin,
|
|
struct blame_entry *sorted)
|
|
{
|
|
if (porigin->suspects)
|
|
porigin->suspects = blame_merge(porigin->suspects, sorted);
|
|
else {
|
|
struct blame_origin *o;
|
|
for (o = get_blame_suspects(porigin->commit); 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
|
|
* 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 repository *r,
|
|
struct blame_origin *origin)
|
|
{
|
|
if (!is_null_oid(&origin->blob_oid))
|
|
return 0;
|
|
if (get_tree_entry(&origin->commit->object.oid, origin->path, &origin->blob_oid, &origin->mode))
|
|
goto error_out;
|
|
if (oid_object_info(r, &origin->blob_oid, NULL) != OBJ_BLOB)
|
|
goto error_out;
|
|
return 0;
|
|
error_out:
|
|
oidclr(&origin->blob_oid);
|
|
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 blame_origin *find_origin(struct repository *r,
|
|
struct commit *parent,
|
|
struct blame_origin *origin)
|
|
{
|
|
struct blame_origin *porigin;
|
|
struct diff_options diff_opts;
|
|
const char *paths[2];
|
|
|
|
/* First check any existing origins */
|
|
for (porigin = get_blame_suspects(parent); 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 blame_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.
|
|
*/
|
|
repo_diff_setup(r, &diff_opts);
|
|
diff_opts.flags.recursive = 1;
|
|
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(get_commit_tree_oid(parent), &diff_opts);
|
|
else
|
|
diff_tree_oid(get_commit_tree_oid(parent),
|
|
get_commit_tree_oid(origin->commit),
|
|
"", &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 blame_origin *find_rename(struct repository *r,
|
|
struct commit *parent,
|
|
struct blame_origin *origin)
|
|
{
|
|
struct blame_origin *porigin = NULL;
|
|
struct diff_options diff_opts;
|
|
int i;
|
|
|
|
repo_diff_setup(r, &diff_opts);
|
|
diff_opts.flags.recursive = 1;
|
|
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(get_commit_tree_oid(parent), &diff_opts);
|
|
else
|
|
diff_tree_oid(get_commit_tree_oid(parent),
|
|
get_commit_tree_oid(origin->commit),
|
|
"", &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));
|
|
blame_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)
|
|
{
|
|
blame_origin_incref(src->suspect);
|
|
blame_origin_decref(dst->suspect);
|
|
memcpy(dst, src, sizeof(*src));
|
|
dst->next = **queue;
|
|
**queue = dst;
|
|
*queue = &dst->next;
|
|
}
|
|
|
|
const char *blame_nth_line(struct blame_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 blame_origin *parent)
|
|
{
|
|
int chunk_end_lno;
|
|
int i;
|
|
memset(split, 0, sizeof(struct blame_entry [3]));
|
|
|
|
for (i = 0; i < 3; i++) {
|
|
split[i].ignored = e->ignored;
|
|
split[i].unblamable = e->unblamable;
|
|
}
|
|
|
|
if (e->s_lno < tlno) {
|
|
/* there is a pre-chunk part not blamed on parent */
|
|
split[0].suspect = blame_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 = blame_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 = blame_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++)
|
|
blame_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;
|
|
}
|
|
|
|
/*
|
|
* Splits a blame entry into two entries at 'len' lines. The original 'e'
|
|
* consists of len lines, i.e. [e->lno, e->lno + len), and the second part,
|
|
* which is returned, consists of the remainder: [e->lno + len, e->lno +
|
|
* e->num_lines). The caller needs to sort out the reference counting for the
|
|
* new entry's suspect.
|
|
*/
|
|
static struct blame_entry *split_blame_at(struct blame_entry *e, int len,
|
|
struct blame_origin *new_suspect)
|
|
{
|
|
struct blame_entry *n = xcalloc(1, sizeof(struct blame_entry));
|
|
|
|
n->suspect = new_suspect;
|
|
n->ignored = e->ignored;
|
|
n->unblamable = e->unblamable;
|
|
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;
|
|
return n;
|
|
}
|
|
|
|
struct blame_line_tracker {
|
|
int is_parent;
|
|
int s_lno;
|
|
};
|
|
|
|
static int are_lines_adjacent(struct blame_line_tracker *first,
|
|
struct blame_line_tracker *second)
|
|
{
|
|
return first->is_parent == second->is_parent &&
|
|
first->s_lno + 1 == second->s_lno;
|
|
}
|
|
|
|
/*
|
|
* This cheap heuristic assigns lines in the chunk to their relative location in
|
|
* the parent's chunk. Any additional lines are left with the target.
|
|
*/
|
|
static void guess_line_blames(struct blame_origin *parent,
|
|
struct blame_origin *target,
|
|
int tlno, int offset, int same, int parent_len,
|
|
struct blame_line_tracker *line_blames)
|
|
{
|
|
int i, best_idx, target_idx;
|
|
int parent_slno = tlno + offset;
|
|
|
|
for (i = 0; i < same - tlno; i++) {
|
|
target_idx = tlno + i;
|
|
best_idx = target_idx + offset;
|
|
if (best_idx < parent_slno + parent_len) {
|
|
line_blames[i].is_parent = 1;
|
|
line_blames[i].s_lno = best_idx;
|
|
} else {
|
|
line_blames[i].is_parent = 0;
|
|
line_blames[i].s_lno = target_idx;
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* This decides which parts of a blame entry go to the parent (added to the
|
|
* ignoredp list) and which stay with the target (added to the diffp list). The
|
|
* actual decision was made in a separate heuristic function, and those answers
|
|
* for the lines in 'e' are in line_blames. This consumes e, essentially
|
|
* putting it on a list.
|
|
*
|
|
* Note that the blame entries on the ignoredp list are not necessarily sorted
|
|
* with respect to the parent's line numbers yet.
|
|
*/
|
|
static void ignore_blame_entry(struct blame_entry *e,
|
|
struct blame_origin *parent,
|
|
struct blame_origin *target,
|
|
struct blame_entry **diffp,
|
|
struct blame_entry **ignoredp,
|
|
struct blame_line_tracker *line_blames)
|
|
{
|
|
int entry_len, nr_lines, i;
|
|
|
|
/*
|
|
* We carve new entries off the front of e. Each entry comes from a
|
|
* contiguous chunk of lines: adjacent lines from the same origin
|
|
* (either the parent or the target).
|
|
*/
|
|
entry_len = 1;
|
|
nr_lines = e->num_lines; /* e changes in the loop */
|
|
for (i = 0; i < nr_lines; i++) {
|
|
struct blame_entry *next = NULL;
|
|
|
|
/*
|
|
* We are often adjacent to the next line - only split the blame
|
|
* entry when we have to.
|
|
*/
|
|
if (i + 1 < nr_lines) {
|
|
if (are_lines_adjacent(&line_blames[i],
|
|
&line_blames[i + 1])) {
|
|
entry_len++;
|
|
continue;
|
|
}
|
|
next = split_blame_at(e, entry_len,
|
|
blame_origin_incref(e->suspect));
|
|
}
|
|
if (line_blames[i].is_parent) {
|
|
e->ignored = 1;
|
|
blame_origin_decref(e->suspect);
|
|
e->suspect = blame_origin_incref(parent);
|
|
e->s_lno = line_blames[i - entry_len + 1].s_lno;
|
|
e->next = *ignoredp;
|
|
*ignoredp = e;
|
|
} else {
|
|
e->unblamable = 1;
|
|
/* e->s_lno is already in the target's address space. */
|
|
e->next = *diffp;
|
|
*diffp = e;
|
|
}
|
|
assert(e->num_lines == entry_len);
|
|
e = next;
|
|
entry_len = 1;
|
|
}
|
|
assert(!e);
|
|
}
|
|
|
|
/*
|
|
* 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.
|
|
*
|
|
* tlno: line number in the target where this chunk begins
|
|
* same: line number in the target where this chunk ends
|
|
* offset: add to tlno to get the chunk starting point in the parent
|
|
* parent_len: number of lines in the parent chunk
|
|
*/
|
|
static void blame_chunk(struct blame_entry ***dstq, struct blame_entry ***srcq,
|
|
int tlno, int offset, int same, int parent_len,
|
|
struct blame_origin *parent,
|
|
struct blame_origin *target, int ignore_diffs)
|
|
{
|
|
struct blame_entry *e = **srcq;
|
|
struct blame_entry *samep = NULL, *diffp = NULL, *ignoredp = NULL;
|
|
struct blame_line_tracker *line_blames = 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 */
|
|
struct blame_entry *n;
|
|
|
|
n = split_blame_at(e, tlno - e->s_lno, e->suspect);
|
|
/* Push new record to diffp */
|
|
n->next = diffp;
|
|
diffp = n;
|
|
} else
|
|
blame_origin_decref(e->suspect);
|
|
/* Pass blame for everything before the differing
|
|
* chunk to the parent */
|
|
e->suspect = blame_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;
|
|
|
|
if (ignore_diffs && same - tlno > 0) {
|
|
line_blames = xcalloc(sizeof(struct blame_line_tracker),
|
|
same - tlno);
|
|
guess_line_blames(parent, target, tlno, offset, same,
|
|
parent_len, line_blames);
|
|
}
|
|
|
|
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
|
|
*/
|
|
struct blame_entry *n;
|
|
|
|
n = split_blame_at(e, same - e->s_lno,
|
|
blame_origin_incref(e->suspect));
|
|
/* Push new record to samep */
|
|
n->next = samep;
|
|
samep = n;
|
|
}
|
|
if (ignore_diffs) {
|
|
ignore_blame_entry(e, parent, target, &diffp, &ignoredp,
|
|
line_blames + e->s_lno - tlno);
|
|
} else {
|
|
e->next = diffp;
|
|
diffp = e;
|
|
}
|
|
e = next;
|
|
}
|
|
free(line_blames);
|
|
if (ignoredp) {
|
|
/*
|
|
* Note ignoredp is not sorted yet, and thus neither is dstq.
|
|
* That list must be sorted before we queue_blames(). We defer
|
|
* sorting until after all diff hunks are processed, so that
|
|
* guess_line_blames() can pick *any* line in the parent. The
|
|
* slight drawback is that we end up sorting all blame entries
|
|
* passed to the parent, including those that are unrelated to
|
|
* changes made by the ignored commit.
|
|
*/
|
|
**dstq = reverse_blame(ignoredp, **dstq);
|
|
*dstq = &ignoredp->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 blame_origin *parent;
|
|
struct blame_origin *target;
|
|
long offset;
|
|
int ignore_diffs;
|
|
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, count_a, d->parent, d->target,
|
|
d->ignore_diffs);
|
|
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 blame_scoreboard *sb,
|
|
struct blame_origin *target,
|
|
struct blame_origin *parent, int ignore_diffs)
|
|
{
|
|
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.target = target;
|
|
d.offset = 0;
|
|
d.ignore_diffs = ignore_diffs;
|
|
d.dstq = &newdest; d.srcq = &target->suspects;
|
|
|
|
fill_origin_blob(&sb->revs->diffopt, parent, &file_p,
|
|
&sb->num_read_blob, ignore_diffs);
|
|
fill_origin_blob(&sb->revs->diffopt, target, &file_o,
|
|
&sb->num_read_blob, ignore_diffs);
|
|
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, 0,
|
|
parent, target, 0);
|
|
*d.dstq = NULL;
|
|
if (ignore_diffs)
|
|
newdest = llist_mergesort(newdest, get_next_blame,
|
|
set_next_blame,
|
|
compare_blame_suspect);
|
|
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 blame_entry_score(struct blame_scoreboard *sb, struct blame_entry *e)
|
|
{
|
|
unsigned score;
|
|
const char *cp, *ep;
|
|
|
|
if (e->score)
|
|
return e->score;
|
|
|
|
score = 1;
|
|
cp = blame_nth_line(sb, e->lno);
|
|
ep = blame_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 potential[] 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 potential and best_so_far and copying potential into
|
|
* bst_so_far as needed.
|
|
*/
|
|
static void copy_split_if_better(struct blame_scoreboard *sb,
|
|
struct blame_entry *best_so_far,
|
|
struct blame_entry *potential)
|
|
{
|
|
int i;
|
|
|
|
if (!potential[1].suspect)
|
|
return;
|
|
if (best_so_far[1].suspect) {
|
|
if (blame_entry_score(sb, &potential[1]) <
|
|
blame_entry_score(sb, &best_so_far[1]))
|
|
return;
|
|
}
|
|
|
|
for (i = 0; i < 3; i++)
|
|
blame_origin_incref(potential[i].suspect);
|
|
decref_split(best_so_far);
|
|
memcpy(best_so_far, potential, 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 blame_scoreboard *sb,
|
|
struct blame_entry *ent,
|
|
int tlno, int plno, int same,
|
|
struct blame_origin *parent,
|
|
struct blame_entry *split)
|
|
{
|
|
if (ent->num_lines <= tlno)
|
|
return;
|
|
if (tlno < same) {
|
|
struct blame_entry potential[3];
|
|
tlno += ent->s_lno;
|
|
same += ent->s_lno;
|
|
split_overlap(potential, ent, tlno, plno, same, parent);
|
|
copy_split_if_better(sb, split, potential);
|
|
decref_split(potential);
|
|
}
|
|
}
|
|
|
|
struct handle_split_cb_data {
|
|
struct blame_scoreboard *sb;
|
|
struct blame_entry *ent;
|
|
struct blame_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 blame_scoreboard *sb,
|
|
struct blame_entry *ent,
|
|
struct blame_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 = blame_nth_line(sb, ent->lno);
|
|
file_o.ptr = (char *) cp;
|
|
file_o.size = blame_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 blame_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 (blame_entry_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 blame_scoreboard *sb,
|
|
struct blame_entry ***blamed,
|
|
struct blame_entry **toosmall,
|
|
struct blame_origin *target,
|
|
struct blame_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, 0);
|
|
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->move_score < blame_entry_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->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 blame_scoreboard *sb,
|
|
struct blame_entry ***blamed,
|
|
struct blame_entry **toosmall,
|
|
struct blame_origin *target,
|
|
struct commit *parent,
|
|
struct blame_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 */
|
|
|
|
repo_diff_setup(sb->repo, &diff_opts);
|
|
diff_opts.flags.recursive = 1;
|
|
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_oid() 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_opts.flags.find_copies_harder = 1;
|
|
|
|
if (is_null_oid(&target->commit->object.oid))
|
|
do_diff_cache(get_commit_tree_oid(parent), &diff_opts);
|
|
else
|
|
diff_tree_oid(get_commit_tree_oid(parent),
|
|
get_commit_tree_oid(target->commit),
|
|
"", &diff_opts);
|
|
|
|
if (!diff_opts.flags.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 blame_origin *norigin;
|
|
mmfile_t file_p;
|
|
struct blame_entry potential[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, 0);
|
|
if (!file_p.ptr)
|
|
continue;
|
|
|
|
for (j = 0; j < num_ents; j++) {
|
|
find_copy_in_blob(sb, blame_list[j].ent,
|
|
norigin, potential, &file_p);
|
|
copy_split_if_better(sb, blame_list[j].split,
|
|
potential);
|
|
decref_split(potential);
|
|
}
|
|
blame_origin_decref(norigin);
|
|
}
|
|
|
|
for (j = 0; j < num_ents; j++) {
|
|
struct blame_entry *split = blame_list[j].split;
|
|
if (split[1].suspect &&
|
|
sb->copy_score < blame_entry_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->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 blame_scoreboard *sb,
|
|
struct blame_origin *origin, struct blame_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) {
|
|
blame_origin_incref(porigin);
|
|
blame_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 blame_scoreboard *sb, struct blame_entry *blamed)
|
|
{
|
|
blamed = llist_mergesort(blamed, get_next_blame, set_next_blame,
|
|
compare_blame_suspect);
|
|
while (blamed)
|
|
{
|
|
struct blame_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 blame_scoreboard *sb, struct blame_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 blame_origin *sg_buf[MAXSG];
|
|
struct blame_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 blame_origin *(*find)(struct repository *, struct commit *, struct blame_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->repo, p, origin);
|
|
if (!porigin)
|
|
continue;
|
|
if (oideq(&porigin->blob_oid, &origin->blob_oid)) {
|
|
pass_whole_blame(sb, origin, porigin);
|
|
blame_origin_decref(porigin);
|
|
goto finish;
|
|
}
|
|
for (j = same = 0; j < i; j++)
|
|
if (sg_origin[j] &&
|
|
oideq(&sg_origin[j]->blob_oid, &porigin->blob_oid)) {
|
|
same = 1;
|
|
break;
|
|
}
|
|
if (!same)
|
|
sg_origin[i] = porigin;
|
|
else
|
|
blame_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 blame_origin *porigin = sg_origin[i];
|
|
if (!porigin)
|
|
continue;
|
|
if (!origin->previous) {
|
|
blame_origin_incref(porigin);
|
|
origin->previous = porigin;
|
|
}
|
|
pass_blame_to_parent(sb, origin, porigin, 0);
|
|
if (!origin->suspects)
|
|
goto finish;
|
|
}
|
|
|
|
/*
|
|
* Pass remaining suspects for ignored commits to their parents.
|
|
*/
|
|
if (oidset_contains(&sb->ignore_list, &commit->object.oid)) {
|
|
for (i = 0, sg = first_scapegoat(revs, commit, sb->reverse);
|
|
i < num_sg && sg;
|
|
sg = sg->next, i++) {
|
|
struct blame_origin *porigin = sg_origin[i];
|
|
|
|
if (!porigin)
|
|
continue;
|
|
pass_blame_to_parent(sb, origin, porigin, 1);
|
|
if (!origin->suspects)
|
|
goto finish;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Optionally find moves in parents' files.
|
|
*/
|
|
if (opt & PICKAXE_BLAME_MOVE) {
|
|
filter_small(sb, &toosmall, &origin->suspects, sb->move_score);
|
|
if (origin->suspects) {
|
|
for (i = 0, sg = first_scapegoat(revs, commit, sb->reverse);
|
|
i < num_sg && sg;
|
|
sg = sg->next, i++) {
|
|
struct blame_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->copy_score > sb->move_score)
|
|
filter_small(sb, &toosmall, &origin->suspects, sb->copy_score);
|
|
else if (sb->copy_score < sb->move_score) {
|
|
origin->suspects = blame_merge(origin->suspects, toosmall);
|
|
toosmall = NULL;
|
|
filter_small(sb, &toosmall, &origin->suspects, sb->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 blame_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]);
|
|
blame_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 blame_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 blame_origin *suspect = get_blame_suspects(commit);
|
|
|
|
/* 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.
|
|
*/
|
|
blame_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;
|
|
}
|
|
}
|
|
blame_origin_decref(suspect);
|
|
|
|
if (sb->debug) /* sanity */
|
|
sanity_check_refcnt(sb);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* 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 blame_scoreboard *sb)
|
|
{
|
|
sb->num_lines = find_line_starts(&sb->lineno, sb->final_buf,
|
|
sb->final_buf_size);
|
|
return sb->num_lines;
|
|
}
|
|
|
|
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;
|
|
obj = deref_tag(revs->repo, 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 = xstrdup_or_null(name);
|
|
return found;
|
|
}
|
|
|
|
static struct commit *dwim_reverse_initial(struct rev_info *revs,
|
|
const char **name_p)
|
|
{
|
|
/*
|
|
* DWIM "git blame --reverse ONE -- PATH" as
|
|
* "git blame --reverse ONE..HEAD -- PATH" but only do so
|
|
* when it makes sense.
|
|
*/
|
|
struct object *obj;
|
|
struct commit *head_commit;
|
|
struct object_id head_oid;
|
|
|
|
if (revs->pending.nr != 1)
|
|
return NULL;
|
|
|
|
/* Is that sole rev a committish? */
|
|
obj = revs->pending.objects[0].item;
|
|
obj = deref_tag(revs->repo, obj, NULL, 0);
|
|
if (obj->type != OBJ_COMMIT)
|
|
return NULL;
|
|
|
|
/* Do we have HEAD? */
|
|
if (!resolve_ref_unsafe("HEAD", RESOLVE_REF_READING, &head_oid, NULL))
|
|
return NULL;
|
|
head_commit = lookup_commit_reference_gently(revs->repo,
|
|
&head_oid, 1);
|
|
if (!head_commit)
|
|
return NULL;
|
|
|
|
/* Turn "ONE" into "ONE..HEAD" then */
|
|
obj->flags |= UNINTERESTING;
|
|
add_pending_object(revs, &head_commit->object, "HEAD");
|
|
|
|
if (name_p)
|
|
*name_p = revs->pending.objects[0].name;
|
|
return (struct commit *)obj;
|
|
}
|
|
|
|
static struct commit *find_single_initial(struct rev_info *revs,
|
|
const char **name_p)
|
|
{
|
|
int i;
|
|
struct commit *found = NULL;
|
|
const char *name = NULL;
|
|
|
|
/*
|
|
* 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;
|
|
obj = deref_tag(revs->repo, 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 up from, %s and %s?",
|
|
revs->pending.objects[i].name, name);
|
|
found = (struct commit *) obj;
|
|
name = revs->pending.objects[i].name;
|
|
}
|
|
|
|
if (!name)
|
|
found = dwim_reverse_initial(revs, &name);
|
|
if (!name)
|
|
die("No commit to dig up from?");
|
|
|
|
if (name_p)
|
|
*name_p = xstrdup(name);
|
|
return found;
|
|
}
|
|
|
|
void init_scoreboard(struct blame_scoreboard *sb)
|
|
{
|
|
memset(sb, 0, sizeof(struct blame_scoreboard));
|
|
sb->move_score = BLAME_DEFAULT_MOVE_SCORE;
|
|
sb->copy_score = BLAME_DEFAULT_COPY_SCORE;
|
|
}
|
|
|
|
void setup_scoreboard(struct blame_scoreboard *sb,
|
|
const char *path,
|
|
struct blame_origin **orig)
|
|
{
|
|
const char *final_commit_name = NULL;
|
|
struct blame_origin *o;
|
|
struct commit *final_commit = NULL;
|
|
enum object_type type;
|
|
|
|
init_blame_suspects(&blame_suspects);
|
|
|
|
if (sb->reverse && sb->contents_from)
|
|
die(_("--contents and --reverse do not blend well."));
|
|
|
|
if (!sb->repo)
|
|
BUG("repo is NULL");
|
|
|
|
if (!sb->reverse) {
|
|
sb->final = find_single_final(sb->revs, &final_commit_name);
|
|
sb->commits.compare = compare_commits_by_commit_date;
|
|
} else {
|
|
sb->final = find_single_initial(sb->revs, &final_commit_name);
|
|
sb->commits.compare = compare_commits_by_reverse_commit_date;
|
|
}
|
|
|
|
if (sb->final && sb->contents_from)
|
|
die(_("cannot use --contents with final commit object name"));
|
|
|
|
if (sb->reverse && sb->revs->first_parent_only)
|
|
sb->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->repo,
|
|
&sb->revs->diffopt,
|
|
path, sb->contents_from);
|
|
add_pending_object(sb->revs, &(sb->final->object), ":");
|
|
}
|
|
|
|
if (sb->reverse && sb->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(sb->revs))
|
|
die(_("revision walk setup failed"));
|
|
|
|
if (sb->reverse && sb->revs->first_parent_only) {
|
|
struct commit *c = final_commit;
|
|
|
|
sb->revs->children.name = "children";
|
|
while (c->parents &&
|
|
!oideq(&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))
|
|
BUG("not unique item in first-parent chain");
|
|
c = c->parents->item;
|
|
}
|
|
|
|
if (!oideq(&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 = get_blame_suspects(sb->final);
|
|
sb->final_buf = xmemdupz(o->file.ptr, o->file.size);
|
|
sb->final_buf_size = o->file.size;
|
|
}
|
|
else {
|
|
o = get_origin(sb->final, path);
|
|
if (fill_blob_sha1_and_mode(sb->repo, o))
|
|
die(_("no such path %s in %s"), path, final_commit_name);
|
|
|
|
if (sb->revs->diffopt.flags.allow_textconv &&
|
|
textconv_object(sb->repo, path, o->mode, &o->blob_oid, 1, (char **) &sb->final_buf,
|
|
&sb->final_buf_size))
|
|
;
|
|
else
|
|
sb->final_buf = read_object_file(&o->blob_oid, &type,
|
|
&sb->final_buf_size);
|
|
|
|
if (!sb->final_buf)
|
|
die(_("cannot read blob %s for path %s"),
|
|
oid_to_hex(&o->blob_oid),
|
|
path);
|
|
}
|
|
sb->num_read_blob++;
|
|
prepare_lines(sb);
|
|
|
|
if (orig)
|
|
*orig = o;
|
|
|
|
free((char *)final_commit_name);
|
|
}
|
|
|
|
|
|
|
|
struct blame_entry *blame_entry_prepend(struct blame_entry *head,
|
|
long start, long end,
|
|
struct blame_origin *o)
|
|
{
|
|
struct blame_entry *new_head = xcalloc(1, sizeof(struct blame_entry));
|
|
new_head->lno = start;
|
|
new_head->num_lines = end - start;
|
|
new_head->suspect = o;
|
|
new_head->s_lno = start;
|
|
new_head->next = head;
|
|
blame_origin_incref(o);
|
|
return new_head;
|
|
}
|