diff options
Diffstat (limited to 'blame.c')
| -rw-r--r-- | blame.c | 176 |
1 files changed, 167 insertions, 9 deletions
@@ -859,6 +859,103 @@ static struct blame_entry *split_blame_at(struct blame_entry *e, int len, 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) { + 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->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 @@ -868,13 +965,20 @@ static struct blame_entry *split_blame_at(struct blame_entry *e, int len, * -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, - struct blame_origin *parent) + 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; + 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; @@ -923,6 +1027,14 @@ static void blame_chunk(struct blame_entry ***dstq, struct blame_entry ***srcq, */ 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; @@ -942,10 +1054,29 @@ static void blame_chunk(struct blame_entry ***dstq, struct blame_entry ***srcq, n->next = samep; samep = n; } - e->next = diffp; - diffp = e; + 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) @@ -954,7 +1085,9 @@ static void blame_chunk(struct blame_entry ***dstq, struct blame_entry ***srcq, 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; }; @@ -967,7 +1100,8 @@ static int blame_chunk_cb(long start_a, long count_a, if (start_a - start_b != d->offset) die("internal error in blame::blame_chunk_cb"); blame_chunk(&d->dstq, &d->srcq, start_b, start_a - start_b, - start_b + count_b, d->parent); + 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; } @@ -979,7 +1113,7 @@ static int blame_chunk_cb(long start_a, long count_a, */ static void pass_blame_to_parent(struct blame_scoreboard *sb, struct blame_origin *target, - struct blame_origin *parent) + struct blame_origin *parent, int ignore_diffs) { mmfile_t file_p, file_o; struct blame_chunk_cb_data d; @@ -989,7 +1123,9 @@ static void pass_blame_to_parent(struct blame_scoreboard *sb, 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); @@ -1001,8 +1137,13 @@ static void pass_blame_to_parent(struct blame_scoreboard *sb, oid_to_hex(&parent->commit->object.oid), oid_to_hex(&target->commit->object.oid)); /* The rest are the same as the parent */ - blame_chunk(&d.dstq, &d.srcq, INT_MAX, d.offset, INT_MAX, parent); + 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; @@ -1506,12 +1647,29 @@ static void pass_blame(struct blame_scoreboard *sb, struct blame_origin *origin, blame_origin_incref(porigin); origin->previous = porigin; } - pass_blame_to_parent(sb, origin, 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) { |