2 * Copyright (c) 2018, 2019, 2020 Stefan Sperling <stsp@openbsd.org>
3 * Copyright (c) 2020 Neels Hofmeyr <neels@hofmeyr.de>
5 * Permission to use, copy, modify, and distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18 #include <sys/queue.h>
32 #include "got_error.h"
33 #include "got_object.h"
34 #include "got_cancel.h"
35 #include "got_blame.h"
36 #include "got_commit_graph.h"
37 #include "got_opentemp.h"
39 #include "got_lib_inflate.h"
40 #include "got_lib_delta.h"
41 #include "got_lib_object.h"
42 #include "got_lib_diff.h"
45 #define MAX(_a,_b) ((_a) > (_b) ? (_a) : (_b))
48 struct got_blame_line {
50 struct got_object_id id;
54 struct diff_config *cfg;
55 int nlines; /* number of lines in file being blamed */
56 int nannotated; /* number of lines already annotated */
57 struct got_blame_line *lines; /* one per line */
61 * These change with every traversed commit. After diffing
62 * commits N:N-1, in preparation for diffing commits N-1:N-2,
63 * data for commit N is retained and flipped into data for N-1.
66 FILE *f1; /* older version from commit N-1. */
67 FILE *f2; /* newer version from commit N. */
78 * Map line numbers of an older version of the file to valid line
79 * numbers in the version of the file being blamed. This map is
80 * updated with each commit we traverse throughout the file's history.
81 * Lines mapped to -1 do not correspond to any line in the version
87 struct diff_data *data1;
88 struct diff_data *data2;
91 static const struct got_error *
92 annotate_line(struct got_blame *blame, int lineno, struct got_object_id *id,
93 const struct got_error *(*cb)(void *, int, int, struct got_object_id *),
96 const struct got_error *err = NULL;
97 struct got_blame_line *line;
99 if (lineno < 0 || lineno >= blame->nlines)
102 line = &blame->lines[lineno];
106 memcpy(&line->id, id, sizeof(line->id));
110 err = cb(arg, blame->nlines, lineno + 1, id);
114 static const struct got_error *
115 blame_changes(struct got_blame *blame, struct diff_result *diff_result,
116 struct got_object_id *commit_id,
117 const struct got_error *(*cb)(void *, int, int, struct got_object_id *),
120 const struct got_error *err = NULL;
122 int idx1 = 0, idx2 = 0;
124 for (i = 0; i < diff_result->chunks.len &&
125 blame->nannotated < blame->nlines; i++) {
126 struct diff_chunk *c = diff_chunk_get(diff_result, i);
127 unsigned int left_count, right_count;
131 * We do not need to worry about idx1/idx2 growing out
132 * of bounds because the diff implementation ensures
133 * that chunk ranges never exceed the number of lines
134 * in the left/right input files.
136 left_count = diff_chunk_get_left_count(c);
137 right_count = diff_chunk_get_right_count(c);
139 if (left_count == right_count) {
140 for (j = 0; j < left_count; j++) {
141 blame->linemap1[idx1++] =
142 blame->linemap2[idx2++];
147 if (right_count == 0) {
148 for (j = 0; j < left_count; j++) {
149 blame->linemap1[idx1++] = -1;
154 for (j = 0; j < right_count; j++) {
155 int ln = blame->linemap2[idx2++];
156 err = annotate_line(blame, ln, commit_id, cb, arg);
159 if (blame->nlines == blame->nannotated)
167 static const struct got_error *
168 blame_prepare_file(FILE *f, unsigned char **p, off_t *size,
169 int *nlines, off_t **line_offsets, struct diff_data *diff_data,
170 const struct diff_config *cfg, struct got_blob_object *blob)
172 const struct got_error *err = NULL;
173 int diff_flags = 0, rc;
175 err = got_object_blob_dump_to_file(size, nlines, line_offsets,
180 #ifndef GOT_DIFF_NO_MMAP
181 *p = mmap(NULL, *size, PROT_READ, MAP_PRIVATE, fileno(f), 0);
182 if (*p == MAP_FAILED)
184 *p = NULL; /* fall back on file I/O */
186 /* Allow blaming lines in binary files even though it's useless. */
187 diff_flags |= DIFF_FLAG_FORCE_TEXT_DATA;
189 rc = diff_atomize_file(diff_data, cfg, f, *p, *size, diff_flags);
191 return got_error_set_errno(rc, "diff_atomize_file");
196 static const struct got_error *
197 blame_commit(struct got_blame *blame, struct got_object_id *id,
198 const char *path, struct got_repository *repo,
199 const struct got_error *(*cb)(void *, int, int, struct got_object_id *),
202 const struct got_error *err = NULL;
203 struct got_commit_object *commit = NULL, *pcommit = NULL;
204 struct got_object_qid *pid = NULL;
205 struct got_object_id *pblob_id = NULL;
206 struct got_blob_object *pblob = NULL;
207 struct diff_result *diff_result = NULL;
209 err = got_object_open_as_commit(&commit, repo, id);
213 pid = STAILQ_FIRST(got_object_commit_get_parent_ids(commit));
215 got_object_commit_close(commit);
219 err = got_object_open_as_commit(&pcommit, repo, pid->id);
223 err = got_object_id_by_path(&pblob_id, repo, pcommit, path);
225 if (err->code == GOT_ERR_NO_TREE_ENTRY)
230 err = got_object_open_as_blob(&pblob, repo, pblob_id, 8192);
234 blame->f1 = got_opentemp();
235 if (blame->f1 == NULL) {
236 err = got_error_from_errno("got_opentemp");
240 err = blame_prepare_file(blame->f1, &blame->map1, &blame->size1,
241 &blame->nlines1, &blame->line_offsets1, blame->data1,
246 diff_result = diff_main(blame->cfg, blame->data1, blame->data2);
247 if (diff_result == NULL) {
248 err = got_error_set_errno(ENOMEM, "malloc");
251 if (diff_result->rc != DIFF_RC_OK) {
252 err = got_error_set_errno(diff_result->rc, "diff");
255 if (diff_result->chunks.len > 0) {
256 if (blame->nlines1 > 0) {
257 blame->linemap1 = calloc(blame->nlines1,
258 sizeof(*blame->linemap1));
259 if (blame->linemap1 == NULL) {
260 err = got_error_from_errno("malloc");
264 err = blame_changes(blame, diff_result, id, cb, arg);
268 err = cb(arg, blame->nlines, -1, id);
271 diff_result_free(diff_result);
273 got_object_commit_close(commit);
275 got_object_commit_close(pcommit);
278 got_object_blob_close(pblob);
282 static const struct got_error *
283 blame_close(struct got_blame *blame)
285 const struct got_error *err = NULL;
287 diff_data_free(blame->data1);
289 diff_data_free(blame->data2);
292 if (munmap(blame->map1, blame->size1) == -1 && err == NULL)
293 err = got_error_from_errno("munmap");
296 if (munmap(blame->map2, blame->size2) == -1 && err == NULL)
297 err = got_error_from_errno("munmap");
299 if (blame->f1 && fclose(blame->f1) == EOF && err == NULL)
300 err = got_error_from_errno("fclose");
301 if (blame->f2 && fclose(blame->f2) == EOF && err == NULL)
302 err = got_error_from_errno("fclose");
304 free(blame->line_offsets1);
305 free(blame->line_offsets2);
306 free(blame->linemap1);
307 free(blame->linemap2);
314 atomize_file(struct diff_data *d, FILE *f, off_t filesize, int nlines,
317 int i, rc = DIFF_RC_OK;
318 int embedded_nul = 0;
320 ARRAYLIST_INIT(d->atoms, nlines);
322 for (i = 0; i < nlines; i++) {
323 struct diff_atom *atom;
324 off_t len, pos = line_offsets[i];
325 unsigned int hash = 0;
328 ARRAYLIST_ADD(atom, d->atoms);
335 len = line_offsets[i + 1] - pos;
337 len = filesize - pos;
339 if (fseeko(f, pos, SEEK_SET) == -1) {
343 for (j = 0; j < len; j++) {
347 rc = EIO; /* unexpected EOF */
353 hash = diff_atom_hash_update(hash, (unsigned char)c);
359 *atom = (struct diff_atom){
362 .at = NULL, /* atom data is not memory-mapped */
368 /* File are considered binary if they contain embedded '\0' bytes. */
370 d->atomizer_flags |= DIFF_ATOMIZER_FOUND_BINARY_DATA;
373 ARRAYLIST_FREE(d->atoms);
379 atomize_file_mmap(struct diff_data *d, unsigned char *p,
380 off_t filesize, int nlines, off_t *line_offsets)
382 int i, rc = DIFF_RC_OK;
383 int embedded_nul = 0;
385 ARRAYLIST_INIT(d->atoms, nlines);
387 for (i = 0; i < nlines; i++) {
388 struct diff_atom *atom;
389 off_t len, pos = line_offsets[i];
390 unsigned int hash = 0;
393 ARRAYLIST_ADD(atom, d->atoms);
400 len = line_offsets[i + 1] - pos;
402 len = filesize - pos;
404 for (j = 0; j < len; j++)
405 hash = diff_atom_hash_update(hash, p[pos + j]);
407 if (!embedded_nul && memchr(&p[pos], '\0', len) != NULL)
410 *atom = (struct diff_atom){
419 /* File are considered binary if they contain embedded '\0' bytes. */
421 d->atomizer_flags |= DIFF_ATOMIZER_FOUND_BINARY_DATA;
424 ARRAYLIST_FREE(d->atoms);
429 /* Implements diff_atomize_func_t */
431 blame_atomize_file(void *arg, struct diff_data *d)
433 struct got_blame *blame = arg;
435 if (d->f == blame->f1) {
437 return atomize_file_mmap(d, blame->map1,
438 blame->size1, blame->nlines1,
439 blame->line_offsets1);
441 return atomize_file(d, blame->f1, blame->size1,
442 blame->nlines1, blame->line_offsets1);
443 } else if (d->f == blame->f2) {
444 if (d->atoms.len > 0) {
445 /* Re-use data from previous commit. */
449 return atomize_file_mmap(d, blame->map2,
450 blame->size2, blame->nlines2,
451 blame->line_offsets2);
453 return atomize_file(d, blame->f2, blame->size2,
454 blame->nlines2, blame->line_offsets2);
460 static const struct got_error *
461 close_file2_and_reuse_file1(struct got_blame *blame)
465 free(blame->line_offsets2);
466 blame->line_offsets2 = blame->line_offsets1;
467 blame->line_offsets1 = NULL;
469 free(blame->linemap2);
470 blame->linemap2 = blame->linemap1;
471 blame->linemap1 = NULL;
474 if (munmap(blame->map2, blame->size2) == -1)
475 return got_error_from_errno("munmap");
476 blame->map2 = blame->map1;
480 blame->size2 = blame->size1;
483 if (fclose(blame->f2) == EOF)
484 return got_error_from_errno("fclose");
485 blame->f2 = blame->f1;
488 blame->nlines2 = blame->nlines1;
491 diff_data_free(blame->data2); /* does not free pointer itself */
492 memset(blame->data2, 0, sizeof(*blame->data2));
494 blame->data2 = blame->data1;
500 static const struct got_error *
501 blame_open(struct got_blame **blamep, const char *path,
502 struct got_object_id *start_commit_id, struct got_repository *repo,
503 const struct got_error *(*cb)(void *, int, int, struct got_object_id *),
504 void *arg, got_cancel_cb cancel_cb, void *cancel_arg)
506 const struct got_error *err = NULL;
507 struct got_commit_object *start_commit = NULL;
508 struct got_object_id *obj_id = NULL;
509 struct got_blob_object *blob = NULL;
510 struct got_blame *blame = NULL;
511 struct got_object_id *id = NULL;
513 struct got_commit_graph *graph = NULL;
517 err = got_object_open_as_commit(&start_commit, repo, start_commit_id);
521 err = got_object_id_by_path(&obj_id, repo, start_commit, path);
525 err = got_object_open_as_blob(&blob, repo, obj_id, 8192);
529 blame = calloc(1, sizeof(*blame));
531 err = got_error_from_errno("calloc");
535 blame->data1 = calloc(1, sizeof(*blame->data1));
536 if (blame->data1 == NULL) {
537 err = got_error_from_errno("calloc");
540 blame->data2 = calloc(1, sizeof(*blame->data2));
541 if (blame->data2 == NULL) {
542 err = got_error_from_errno("calloc");
546 blame->f2 = got_opentemp();
547 if (blame->f2 == NULL) {
548 err = got_error_from_errno("got_opentemp");
551 err = got_diff_get_config(&blame->cfg, GOT_DIFF_ALGORITHM_PATIENCE,
552 blame_atomize_file, blame);
556 err = blame_prepare_file(blame->f2, &blame->map2, &blame->size2,
557 &blame->nlines2, &blame->line_offsets2, blame->data2,
559 blame->nlines = blame->nlines2;
560 if (err || blame->nlines == 0)
563 got_object_blob_close(blob);
566 /* Don't include \n at EOF in the blame line count. */
567 if (blame->line_offsets2[blame->nlines - 1] == blame->size2)
570 blame->lines = calloc(blame->nlines, sizeof(*blame->lines));
571 if (blame->lines == NULL) {
572 err = got_error_from_errno("calloc");
576 blame->linemap2 = calloc(blame->nlines2, sizeof(*blame->linemap2));
577 if (blame->linemap2 == NULL) {
578 err = got_error_from_errno("calloc");
581 for (lineno = 0; lineno < blame->nlines2; lineno++)
582 blame->linemap2[lineno] = lineno;
584 err = got_commit_graph_open(&graph, path, 1);
588 err = got_commit_graph_iter_start(graph, start_commit_id, repo,
589 cancel_cb, cancel_arg);
593 struct got_object_id *next_id;
594 err = got_commit_graph_iter_next(&next_id, graph, repo,
595 cancel_cb, cancel_arg);
597 if (err->code == GOT_ERR_ITER_COMPLETED) {
605 err = blame_commit(blame, id, path, repo, cb, arg);
607 if (err->code == GOT_ERR_ITER_COMPLETED)
611 if (blame->nannotated == blame->nlines)
614 err = close_file2_and_reuse_file1(blame);
620 if (id && blame->nannotated < blame->nlines) {
621 /* Annotate remaining non-annotated lines with last commit. */
622 for (lineno = 0; lineno < blame->nlines; lineno++) {
623 err = annotate_line(blame, lineno, id, cb, arg);
631 got_commit_graph_close(graph);
634 got_object_blob_close(blob);
636 got_object_commit_close(start_commit);
646 const struct got_error *
647 got_blame(const char *path, struct got_object_id *commit_id,
648 struct got_repository *repo,
649 const struct got_error *(*cb)(void *, int, int, struct got_object_id *),
650 void *arg, got_cancel_cb cancel_cb, void* cancel_arg)
652 const struct got_error *err = NULL, *close_err = NULL;
653 struct got_blame *blame;
656 if (asprintf(&abspath, "%s%s", path[0] == '/' ? "" : "/", path) == -1)
657 return got_error_from_errno2("asprintf", path);
659 err = blame_open(&blame, abspath, commit_id, repo, cb, arg,
660 cancel_cb, cancel_arg);
663 close_err = blame_close(blame);
664 return err ? err : close_err;