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2530 lines (2272 loc) · 64.1 KB
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/*
* Blame
*
* Copyright (c) 2006, Junio C Hamano
*/
#include "cache.h"
#include "builtin.h"
#include "blob.h"
#include "commit.h"
#include "tag.h"
#include "tree-walk.h"
#include "diff.h"
#include "diffcore.h"
#include "revision.h"
#include "quote.h"
#include "xdiff-interface.h"
#include "cache-tree.h"
#include "string-list.h"
#include "mailmap.h"
#include "parse-options.h"
#include "utf8.h"
#include "userdiff.h"
static char blame_usage[] = "git blame [options] [rev-opts] [rev] [--] file";
static const char *blame_opt_usage[] = {
blame_usage,
"",
"[rev-opts] are documented in git-rev-list(1)",
NULL
};
static int longest_file;
static int longest_author;
static int max_orig_digits;
static int max_digits;
static int max_score_digits;
static int show_root;
static int reverse;
static int blank_boundary;
static int incremental;
static int xdl_opts;
static enum date_mode blame_date_mode = DATE_ISO8601;
static size_t blame_date_width;
static struct string_list mailmap;
#ifndef DEBUG
#define DEBUG 0
#endif
/* stats */
static int num_read_blob;
static int num_get_patch;
static int num_commits;
#define PICKAXE_BLAME_MOVE 01
#define PICKAXE_BLAME_COPY 02
#define PICKAXE_BLAME_COPY_HARDER 04
#define PICKAXE_BLAME_COPY_HARDEST 010
/*
* blame for a blame_entry with score lower than these thresholds
* is not passed to the parent using move/copy logic.
*/
static unsigned blame_move_score;
static unsigned blame_copy_score;
#define BLAME_DEFAULT_MOVE_SCORE 20
#define BLAME_DEFAULT_COPY_SCORE 40
/* bits #0..7 in revision.h, #8..11 used for merge_bases() in commit.c */
#define METAINFO_SHOWN (1u<<12)
#define MORE_THAN_ONE_PATH (1u<<13)
/*
* One blob in a commit that is being suspected
*/
struct origin {
int refcnt;
struct origin *previous;
struct commit *commit;
mmfile_t file;
unsigned char blob_sha1[20];
char path[FLEX_ARRAY];
};
/*
* Prepare diff_filespec and convert it using diff textconv API
* if the textconv driver exists.
* Return 1 if the conversion succeeds, 0 otherwise.
*/
int textconv_object(const char *path,
const unsigned char *sha1,
char **buf,
unsigned long *buf_size)
{
struct diff_filespec *df;
struct userdiff_driver *textconv;
df = alloc_filespec(path);
fill_filespec(df, sha1, S_IFREG | 0664);
textconv = get_textconv(df);
if (!textconv) {
free_filespec(df);
return 0;
}
*buf_size = fill_textconv(textconv, df, buf);
free_filespec(df);
return 1;
}
/*
* Given an origin, prepare mmfile_t structure to be used by the
* diff machinery
*/
static void fill_origin_blob(struct diff_options *opt,
struct origin *o, mmfile_t *file)
{
if (!o->file.ptr) {
enum object_type type;
unsigned long file_size;
num_read_blob++;
if (DIFF_OPT_TST(opt, ALLOW_TEXTCONV) &&
textconv_object(o->path, o->blob_sha1, &file->ptr, &file_size))
;
else
file->ptr = read_sha1_file(o->blob_sha1, &type, &file_size);
file->size = file_size;
if (!file->ptr)
die("Cannot read blob %s for path %s",
sha1_to_hex(o->blob_sha1),
o->path);
o->file = *file;
}
else
*file = o->file;
}
/*
* Origin is refcounted and usually we keep the blob contents to be
* reused.
*/
static inline struct origin *origin_incref(struct origin *o)
{
if (o)
o->refcnt++;
return o;
}
static void origin_decref(struct origin *o)
{
if (o && --o->refcnt <= 0) {
if (o->previous)
origin_decref(o->previous);
free(o->file.ptr);
free(o);
}
}
static void drop_origin_blob(struct origin *o)
{
if (o->file.ptr) {
free(o->file.ptr);
o->file.ptr = NULL;
}
}
/*
* Each group of lines is described by a blame_entry; it can be split
* as we pass blame to the parents. They form a linked list in the
* scoreboard structure, sorted by the target line number.
*/
struct blame_entry {
struct blame_entry *prev;
struct blame_entry *next;
/* the first line of this group in the final image;
* internally all line numbers are 0 based.
*/
int lno;
/* how many lines this group has */
int num_lines;
/* the commit that introduced this group into the final image */
struct origin *suspect;
/* true if the suspect is truly guilty; false while we have not
* checked if the group came from one of its parents.
*/
char guilty;
/* true if the entry has been scanned for copies in the current parent
*/
char scanned;
/* the line number of the first line of this group in the
* suspect's file; internally all line numbers are 0 based.
*/
int s_lno;
/* how significant this entry is -- cached to avoid
* scanning the lines over and over.
*/
unsigned score;
};
/*
* The current state of the blame assignment.
*/
struct scoreboard {
/* the final commit (i.e. where we started digging from) */
struct commit *final;
struct rev_info *revs;
const char *path;
/*
* The contents in the final image.
* Used by many functions to obtain contents of the nth line,
* indexed with scoreboard.lineno[blame_entry.lno].
*/
const char *final_buf;
unsigned long final_buf_size;
/* linked list of blames */
struct blame_entry *ent;
/* look-up a line in the final buffer */
int num_lines;
int *lineno;
};
static inline int same_suspect(struct origin *a, struct origin *b)
{
if (a == b)
return 1;
if (a->commit != b->commit)
return 0;
return !strcmp(a->path, b->path);
}
static void sanity_check_refcnt(struct scoreboard *);
/*
* If two blame entries that are next to each other came from
* contiguous lines in the same origin (i.e. <commit, path> pair),
* merge them together.
*/
static void coalesce(struct scoreboard *sb)
{
struct blame_entry *ent, *next;
for (ent = sb->ent; ent && (next = ent->next); ent = next) {
if (same_suspect(ent->suspect, next->suspect) &&
ent->guilty == next->guilty &&
ent->s_lno + ent->num_lines == next->s_lno) {
ent->num_lines += next->num_lines;
ent->next = next->next;
if (ent->next)
ent->next->prev = ent;
origin_decref(next->suspect);
free(next);
ent->score = 0;
next = ent; /* again */
}
}
if (DEBUG) /* sanity */
sanity_check_refcnt(sb);
}
/*
* Given a commit and a path in it, create a new origin structure.
* The callers that add blame to the scoreboard should use
* get_origin() to obtain shared, refcounted copy instead of calling
* this function directly.
*/
static struct origin *make_origin(struct commit *commit, const char *path)
{
struct origin *o;
o = xcalloc(1, sizeof(*o) + strlen(path) + 1);
o->commit = commit;
o->refcnt = 1;
strcpy(o->path, path);
return o;
}
/*
* Locate an existing origin or create a new one.
*/
static struct origin *get_origin(struct scoreboard *sb,
struct commit *commit,
const char *path)
{
struct blame_entry *e;
for (e = sb->ent; e; e = e->next) {
if (e->suspect->commit == commit &&
!strcmp(e->suspect->path, path))
return origin_incref(e->suspect);
}
return make_origin(commit, path);
}
/*
* Fill the blob_sha1 field of an origin if it hasn't, so that later
* call to fill_origin_blob() can use it to locate the data. blob_sha1
* for an origin is also used to pass the blame for the entire file to
* the parent to detect the case where a child's blob is identical to
* that of its parent's.
*/
static int fill_blob_sha1(struct origin *origin)
{
unsigned mode;
if (!is_null_sha1(origin->blob_sha1))
return 0;
if (get_tree_entry(origin->commit->object.sha1,
origin->path,
origin->blob_sha1, &mode))
goto error_out;
if (sha1_object_info(origin->blob_sha1, NULL) != OBJ_BLOB)
goto error_out;
return 0;
error_out:
hashclr(origin->blob_sha1);
return -1;
}
/*
* We have an origin -- check if the same path exists in the
* parent and return an origin structure to represent it.
*/
static struct origin *find_origin(struct scoreboard *sb,
struct commit *parent,
struct origin *origin)
{
struct origin *porigin = NULL;
struct diff_options diff_opts;
const char *paths[2];
if (parent->util) {
/*
* Each commit object can cache one origin in that
* commit. This is a freestanding copy of origin and
* not refcounted.
*/
struct origin *cached = parent->util;
if (!strcmp(cached->path, origin->path)) {
/*
* The same path between origin and its parent
* without renaming -- the most common case.
*/
porigin = get_origin(sb, parent, cached->path);
/*
* If the origin was newly created (i.e. get_origin
* would call make_origin if none is found in the
* scoreboard), it does not know the blob_sha1,
* so copy it. Otherwise porigin was in the
* scoreboard and already knows blob_sha1.
*/
if (porigin->refcnt == 1)
hashcpy(porigin->blob_sha1, cached->blob_sha1);
return porigin;
}
/* otherwise it was not very useful; free it */
free(parent->util);
parent->util = NULL;
}
/* See if the origin->path is different between parent
* and origin first. Most of the time they are the
* same and diff-tree is fairly efficient about this.
*/
diff_setup(&diff_opts);
DIFF_OPT_SET(&diff_opts, RECURSIVE);
diff_opts.detect_rename = 0;
diff_opts.output_format = DIFF_FORMAT_NO_OUTPUT;
paths[0] = origin->path;
paths[1] = NULL;
diff_tree_setup_paths(paths, &diff_opts);
if (diff_setup_done(&diff_opts) < 0)
die("diff-setup");
if (is_null_sha1(origin->commit->object.sha1))
do_diff_cache(parent->tree->object.sha1, &diff_opts);
else
diff_tree_sha1(parent->tree->object.sha1,
origin->commit->tree->object.sha1,
"", &diff_opts);
diffcore_std(&diff_opts);
if (!diff_queued_diff.nr) {
/* The path is the same as parent */
porigin = get_origin(sb, parent, origin->path);
hashcpy(porigin->blob_sha1, origin->blob_sha1);
} else {
/*
* Since origin->path is a pathspec, if the parent
* commit had it as a directory, we will see a whole
* bunch of deletion of files in the directory that we
* do not care about.
*/
int i;
struct diff_filepair *p = NULL;
for (i = 0; i < diff_queued_diff.nr; i++) {
const char *name;
p = diff_queued_diff.queue[i];
name = p->one->path ? p->one->path : p->two->path;
if (!strcmp(name, origin->path))
break;
}
if (!p)
die("internal error in blame::find_origin");
switch (p->status) {
default:
die("internal error in blame::find_origin (%c)",
p->status);
case 'M':
porigin = get_origin(sb, parent, origin->path);
hashcpy(porigin->blob_sha1, p->one->sha1);
break;
case 'A':
case 'T':
/* Did not exist in parent, or type changed */
break;
}
}
diff_flush(&diff_opts);
diff_tree_release_paths(&diff_opts);
if (porigin) {
/*
* Create a freestanding copy that is not part of
* the refcounted origin found in the scoreboard, and
* cache it in the commit.
*/
struct origin *cached;
cached = make_origin(porigin->commit, porigin->path);
hashcpy(cached->blob_sha1, porigin->blob_sha1);
parent->util = cached;
}
return porigin;
}
/*
* We have an origin -- find the path that corresponds to it in its
* parent and return an origin structure to represent it.
*/
static struct origin *find_rename(struct scoreboard *sb,
struct commit *parent,
struct origin *origin)
{
struct origin *porigin = NULL;
struct diff_options diff_opts;
int i;
const char *paths[2];
diff_setup(&diff_opts);
DIFF_OPT_SET(&diff_opts, RECURSIVE);
diff_opts.detect_rename = DIFF_DETECT_RENAME;
diff_opts.output_format = DIFF_FORMAT_NO_OUTPUT;
diff_opts.single_follow = origin->path;
paths[0] = NULL;
diff_tree_setup_paths(paths, &diff_opts);
if (diff_setup_done(&diff_opts) < 0)
die("diff-setup");
if (is_null_sha1(origin->commit->object.sha1))
do_diff_cache(parent->tree->object.sha1, &diff_opts);
else
diff_tree_sha1(parent->tree->object.sha1,
origin->commit->tree->object.sha1,
"", &diff_opts);
diffcore_std(&diff_opts);
for (i = 0; i < diff_queued_diff.nr; i++) {
struct diff_filepair *p = diff_queued_diff.queue[i];
if ((p->status == 'R' || p->status == 'C') &&
!strcmp(p->two->path, origin->path)) {
porigin = get_origin(sb, parent, p->one->path);
hashcpy(porigin->blob_sha1, p->one->sha1);
break;
}
}
diff_flush(&diff_opts);
diff_tree_release_paths(&diff_opts);
return porigin;
}
/*
* Link in a new blame entry to the scoreboard. Entries that cover the
* same line range have been removed from the scoreboard previously.
*/
static void add_blame_entry(struct scoreboard *sb, struct blame_entry *e)
{
struct blame_entry *ent, *prev = NULL;
origin_incref(e->suspect);
for (ent = sb->ent; ent && ent->lno < e->lno; ent = ent->next)
prev = ent;
/* prev, if not NULL, is the last one that is below e */
e->prev = prev;
if (prev) {
e->next = prev->next;
prev->next = e;
}
else {
e->next = sb->ent;
sb->ent = e;
}
if (e->next)
e->next->prev = e;
}
/*
* src typically is on-stack; we want to copy the information in it to
* a malloced blame_entry that is already on the linked list of the
* scoreboard. The origin of dst loses a refcnt while the origin of src
* gains one.
*/
static void dup_entry(struct blame_entry *dst, struct blame_entry *src)
{
struct blame_entry *p, *n;
p = dst->prev;
n = dst->next;
origin_incref(src->suspect);
origin_decref(dst->suspect);
memcpy(dst, src, sizeof(*src));
dst->prev = p;
dst->next = n;
dst->score = 0;
}
static const char *nth_line(struct scoreboard *sb, int lno)
{
return sb->final_buf + sb->lineno[lno];
}
/*
* It is known that lines between tlno to same came from parent, and e
* has an overlap with that range. it also is known that parent's
* line plno corresponds to e's line tlno.
*
* <---- e ----->
* <------>
* <------------>
* <------------>
* <------------------>
*
* Split e into potentially three parts; before this chunk, the chunk
* to be blamed for the parent, and after that portion.
*/
static void split_overlap(struct blame_entry *split,
struct blame_entry *e,
int tlno, int plno, int same,
struct origin *parent)
{
int chunk_end_lno;
memset(split, 0, sizeof(struct blame_entry [3]));
if (e->s_lno < tlno) {
/* there is a pre-chunk part not blamed on parent */
split[0].suspect = origin_incref(e->suspect);
split[0].lno = e->lno;
split[0].s_lno = e->s_lno;
split[0].num_lines = tlno - e->s_lno;
split[1].lno = e->lno + tlno - e->s_lno;
split[1].s_lno = plno;
}
else {
split[1].lno = e->lno;
split[1].s_lno = plno + (e->s_lno - tlno);
}
if (same < e->s_lno + e->num_lines) {
/* there is a post-chunk part not blamed on parent */
split[2].suspect = origin_incref(e->suspect);
split[2].lno = e->lno + (same - e->s_lno);
split[2].s_lno = e->s_lno + (same - e->s_lno);
split[2].num_lines = e->s_lno + e->num_lines - same;
chunk_end_lno = split[2].lno;
}
else
chunk_end_lno = e->lno + e->num_lines;
split[1].num_lines = chunk_end_lno - split[1].lno;
/*
* if it turns out there is nothing to blame the parent for,
* forget about the splitting. !split[1].suspect signals this.
*/
if (split[1].num_lines < 1)
return;
split[1].suspect = origin_incref(parent);
}
/*
* split_overlap() divided an existing blame e into up to three parts
* in split. Adjust the linked list of blames in the scoreboard to
* reflect the split.
*/
static void split_blame(struct scoreboard *sb,
struct blame_entry *split,
struct blame_entry *e)
{
struct blame_entry *new_entry;
if (split[0].suspect && split[2].suspect) {
/* The first part (reuse storage for the existing entry e) */
dup_entry(e, &split[0]);
/* The last part -- me */
new_entry = xmalloc(sizeof(*new_entry));
memcpy(new_entry, &(split[2]), sizeof(struct blame_entry));
add_blame_entry(sb, new_entry);
/* ... and the middle part -- parent */
new_entry = xmalloc(sizeof(*new_entry));
memcpy(new_entry, &(split[1]), sizeof(struct blame_entry));
add_blame_entry(sb, new_entry);
}
else if (!split[0].suspect && !split[2].suspect)
/*
* The parent covers the entire area; reuse storage for
* e and replace it with the parent.
*/
dup_entry(e, &split[1]);
else if (split[0].suspect) {
/* me and then parent */
dup_entry(e, &split[0]);
new_entry = xmalloc(sizeof(*new_entry));
memcpy(new_entry, &(split[1]), sizeof(struct blame_entry));
add_blame_entry(sb, new_entry);
}
else {
/* parent and then me */
dup_entry(e, &split[1]);
new_entry = xmalloc(sizeof(*new_entry));
memcpy(new_entry, &(split[2]), sizeof(struct blame_entry));
add_blame_entry(sb, new_entry);
}
if (DEBUG) { /* sanity */
struct blame_entry *ent;
int lno = sb->ent->lno, corrupt = 0;
for (ent = sb->ent; ent; ent = ent->next) {
if (lno != ent->lno)
corrupt = 1;
if (ent->s_lno < 0)
corrupt = 1;
lno += ent->num_lines;
}
if (corrupt) {
lno = sb->ent->lno;
for (ent = sb->ent; ent; ent = ent->next) {
printf("L %8d l %8d n %8d\n",
lno, ent->lno, ent->num_lines);
lno = ent->lno + ent->num_lines;
}
die("oops");
}
}
}
/*
* After splitting the blame, the origins used by the
* on-stack blame_entry should lose one refcnt each.
*/
static void decref_split(struct blame_entry *split)
{
int i;
for (i = 0; i < 3; i++)
origin_decref(split[i].suspect);
}
/*
* Helper for blame_chunk(). blame_entry e is known to overlap with
* the patch hunk; split it and pass blame to the parent.
*/
static void blame_overlap(struct scoreboard *sb, struct blame_entry *e,
int tlno, int plno, int same,
struct origin *parent)
{
struct blame_entry split[3];
split_overlap(split, e, tlno, plno, same, parent);
if (split[1].suspect)
split_blame(sb, split, e);
decref_split(split);
}
/*
* Find the line number of the last line the target is suspected for.
*/
static int find_last_in_target(struct scoreboard *sb, struct origin *target)
{
struct blame_entry *e;
int last_in_target = -1;
for (e = sb->ent; e; e = e->next) {
if (e->guilty || !same_suspect(e->suspect, target))
continue;
if (last_in_target < e->s_lno + e->num_lines)
last_in_target = e->s_lno + e->num_lines;
}
return last_in_target;
}
/*
* Process one hunk from the patch between the current suspect for
* blame_entry e and its parent. Find and split the overlap, and
* pass blame to the overlapping part to the parent.
*/
static void blame_chunk(struct scoreboard *sb,
int tlno, int plno, int same,
struct origin *target, struct origin *parent)
{
struct blame_entry *e;
for (e = sb->ent; e; e = e->next) {
if (e->guilty || !same_suspect(e->suspect, target))
continue;
if (same <= e->s_lno)
continue;
if (tlno < e->s_lno + e->num_lines)
blame_overlap(sb, e, tlno, plno, same, parent);
}
}
struct blame_chunk_cb_data {
struct scoreboard *sb;
struct origin *target;
struct origin *parent;
long plno;
long tlno;
};
static void blame_chunk_cb(void *data, long same, long p_next, long t_next)
{
struct blame_chunk_cb_data *d = data;
blame_chunk(d->sb, d->tlno, d->plno, same, d->target, d->parent);
d->plno = p_next;
d->tlno = t_next;
}
/*
* 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 int pass_blame_to_parent(struct scoreboard *sb,
struct origin *target,
struct origin *parent)
{
int last_in_target;
mmfile_t file_p, file_o;
struct blame_chunk_cb_data d;
xpparam_t xpp;
xdemitconf_t xecfg;
memset(&d, 0, sizeof(d));
d.sb = sb; d.target = target; d.parent = parent;
last_in_target = find_last_in_target(sb, target);
if (last_in_target < 0)
return 1; /* nothing remains for this target */
fill_origin_blob(&sb->revs->diffopt, parent, &file_p);
fill_origin_blob(&sb->revs->diffopt, target, &file_o);
num_get_patch++;
memset(&xpp, 0, sizeof(xpp));
xpp.flags = xdl_opts;
memset(&xecfg, 0, sizeof(xecfg));
xecfg.ctxlen = 0;
xdi_diff_hunks(&file_p, &file_o, blame_chunk_cb, &d, &xpp, &xecfg);
/* The rest (i.e. anything after tlno) are the same as the parent */
blame_chunk(sb, d.tlno, d.plno, last_in_target, target, parent);
return 0;
}
/*
* The lines in blame_entry after splitting blames many times can become
* very small and trivial, and at some point it becomes pointless to
* blame the parents. E.g. "\t\t}\n\t}\n\n" appears everywhere in any
* ordinary C program, and it is not worth to say it was copied from
* totally unrelated file in the parent.
*
* Compute how trivial the lines in the blame_entry are.
*/
static unsigned ent_score(struct scoreboard *sb, struct blame_entry *e)
{
unsigned score;
const char *cp, *ep;
if (e->score)
return e->score;
score = 1;
cp = nth_line(sb, e->lno);
ep = nth_line(sb, e->lno + e->num_lines);
while (cp < ep) {
unsigned ch = *((unsigned char *)cp);
if (isalnum(ch))
score++;
cp++;
}
e->score = score;
return score;
}
/*
* best_so_far[] and this[] are both a split of an existing blame_entry
* that passes blame to the parent. Maintain best_so_far the best split
* so far, by comparing this and best_so_far and copying this into
* bst_so_far as needed.
*/
static void copy_split_if_better(struct scoreboard *sb,
struct blame_entry *best_so_far,
struct blame_entry *this)
{
int i;
if (!this[1].suspect)
return;
if (best_so_far[1].suspect) {
if (ent_score(sb, &this[1]) < ent_score(sb, &best_so_far[1]))
return;
}
for (i = 0; i < 3; i++)
origin_incref(this[i].suspect);
decref_split(best_so_far);
memcpy(best_so_far, this, sizeof(struct blame_entry [3]));
}
/*
* We are looking at a part of the final image represented by
* ent (tlno and same are offset by ent->s_lno).
* tlno is where we are looking at in the final image.
* up to (but not including) same match preimage.
* plno is where we are looking at in the preimage.
*
* <-------------- final image ---------------------->
* <------ent------>
* ^tlno ^same
* <---------preimage----->
* ^plno
*
* All line numbers are 0-based.
*/
static void handle_split(struct scoreboard *sb,
struct blame_entry *ent,
int tlno, int plno, int same,
struct origin *parent,
struct blame_entry *split)
{
if (ent->num_lines <= tlno)
return;
if (tlno < same) {
struct blame_entry this[3];
tlno += ent->s_lno;
same += ent->s_lno;
split_overlap(this, ent, tlno, plno, same, parent);
copy_split_if_better(sb, split, this);
decref_split(this);
}
}
struct handle_split_cb_data {
struct scoreboard *sb;
struct blame_entry *ent;
struct origin *parent;
struct blame_entry *split;
long plno;
long tlno;
};
static void handle_split_cb(void *data, long same, long p_next, long t_next)
{
struct handle_split_cb_data *d = data;
handle_split(d->sb, d->ent, d->tlno, d->plno, same, d->parent, d->split);
d->plno = p_next;
d->tlno = t_next;
}
/*
* Find the lines from parent that are the same as ent so that
* we can pass blames to it. file_p has the blob contents for
* the parent.
*/
static void find_copy_in_blob(struct scoreboard *sb,
struct blame_entry *ent,
struct origin *parent,
struct blame_entry *split,
mmfile_t *file_p)
{
const char *cp;
int cnt;
mmfile_t file_o;
struct handle_split_cb_data d;
xpparam_t xpp;
xdemitconf_t xecfg;
memset(&d, 0, sizeof(d));
d.sb = sb; d.ent = ent; d.parent = parent; d.split = split;
/*
* Prepare mmfile that contains only the lines in ent.
*/
cp = nth_line(sb, ent->lno);
file_o.ptr = (char *) cp;
cnt = ent->num_lines;
while (cnt && cp < sb->final_buf + sb->final_buf_size) {
if (*cp++ == '\n')
cnt--;
}
file_o.size = cp - file_o.ptr;
/*
* file_o is a part of final image we are annotating.
* file_p partially may match that image.
*/
memset(&xpp, 0, sizeof(xpp));
xpp.flags = xdl_opts;
memset(&xecfg, 0, sizeof(xecfg));
xecfg.ctxlen = 1;
memset(split, 0, sizeof(struct blame_entry [3]));
xdi_diff_hunks(file_p, &file_o, handle_split_cb, &d, &xpp, &xecfg);
/* remainder, if any, all match the preimage */
handle_split(sb, ent, d.tlno, d.plno, ent->num_lines, parent, split);
}
/*
* See if lines currently target is suspected for can be attributed to
* parent.
*/
static int find_move_in_parent(struct scoreboard *sb,
struct origin *target,
struct origin *parent)
{
int last_in_target, made_progress;
struct blame_entry *e, split[3];
mmfile_t file_p;
last_in_target = find_last_in_target(sb, target);
if (last_in_target < 0)
return 1; /* nothing remains for this target */
fill_origin_blob(&sb->revs->diffopt, parent, &file_p);
if (!file_p.ptr)
return 0;
made_progress = 1;
while (made_progress) {
made_progress = 0;
for (e = sb->ent; e; e = e->next) {
if (e->guilty || !same_suspect(e->suspect, target) ||
ent_score(sb, e) < blame_move_score)
continue;
find_copy_in_blob(sb, e, parent, split, &file_p);
if (split[1].suspect &&
blame_move_score < ent_score(sb, &split[1])) {
split_blame(sb, split, e);
made_progress = 1;
}
decref_split(split);
}
}
return 0;
}
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 scoreboard *sb,
struct origin *target,
int min_score,
int *num_ents_p)
{
struct blame_entry *e;
int num_ents, i;
struct blame_list *blame_list = NULL;
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