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>
33 #include "got_error.h"
34 #include "got_object.h"
35 #include "got_cancel.h"
36 #include "got_commit_graph.h"
37 #include "got_opentemp.h"
39 #include "got_blame.h"
41 #include "got_lib_inflate.h"
42 #include "got_lib_delta.h"
43 #include "got_lib_object.h"
44 #include "got_lib_diff.h"
47 #define MAX(_a,_b) ((_a) > (_b) ? (_a) : (_b))
50 struct got_blame_line {
52 struct got_object_id id;
56 struct diff_config *cfg;
57 int nlines; /* number of lines in file being blamed */
58 int nannotated; /* number of lines already annotated */
59 struct got_blame_line *lines; /* one per line */
63 * These change with every traversed commit. After diffing
64 * commits N:N-1, in preparation for diffing commits N-1:N-2,
65 * data for commit N is retained and flipped into data for N-1.
68 FILE *f1; /* older version from commit N-1. */
69 FILE *f2; /* newer version from commit N. */
81 * Map line numbers of an older version of the file to valid line
82 * numbers in the version of the file being blamed. This map is
83 * updated with each commit we traverse throughout the file's history.
84 * Lines mapped to -1 do not correspond to any line in the version
90 struct diff_data *data1;
91 struct diff_data *data2;
94 static const struct got_error *
95 annotate_line(struct got_blame *blame, int lineno,
96 struct got_commit_object *commit, struct got_object_id *id,
97 got_blame_cb cb, void *arg)
99 const struct got_error *err = NULL;
100 struct got_blame_line *line;
102 if (lineno < 0 || lineno >= blame->nlines)
105 line = &blame->lines[lineno];
109 memcpy(&line->id, id, sizeof(line->id));
113 err = cb(arg, blame->nlines, lineno + 1, commit, id);
117 static const struct got_error *
118 blame_changes(struct got_blame *blame, struct diff_result *diff_result,
119 struct got_commit_object *commit, struct got_object_id *commit_id,
120 got_blame_cb cb, void *arg)
122 const struct got_error *err = NULL;
124 int idx1 = 0, idx2 = 0;
126 for (i = 0; i < diff_result->chunks.len &&
127 blame->nannotated < blame->nlines; i++) {
128 struct diff_chunk *c = diff_chunk_get(diff_result, i);
129 unsigned int left_count, right_count;
133 * We do not need to worry about idx1/idx2 growing out
134 * of bounds because the diff implementation ensures
135 * that chunk ranges never exceed the number of lines
136 * in the left/right input files.
138 left_count = diff_chunk_get_left_count(c);
139 right_count = diff_chunk_get_right_count(c);
141 if (left_count == right_count) {
142 for (j = 0; j < left_count; j++) {
143 blame->linemap1[idx1++] =
144 blame->linemap2[idx2++];
149 if (right_count == 0) {
150 for (j = 0; j < left_count; j++) {
151 blame->linemap1[idx1++] = -1;
156 for (j = 0; j < right_count; j++) {
157 int ln = blame->linemap2[idx2++];
158 err = annotate_line(blame, ln, commit, commit_id,
162 if (blame->nlines == blame->nannotated)
170 static const struct got_error *
171 blame_prepare_file(FILE *f, unsigned char **p, off_t *size,
172 int *nlines, off_t **line_offsets, struct diff_data *diff_data,
173 const struct diff_config *cfg, struct got_blob_object *blob)
175 const struct got_error *err = NULL;
176 int diff_flags = 0, rc;
178 err = got_object_blob_dump_to_file(size, nlines, line_offsets,
183 #ifndef GOT_DIFF_NO_MMAP
184 *p = mmap(NULL, *size, PROT_READ, MAP_PRIVATE, fileno(f), 0);
185 if (*p == MAP_FAILED)
187 *p = NULL; /* fall back on file I/O */
189 /* Allow blaming lines in binary files even though it's useless. */
190 diff_flags |= DIFF_FLAG_FORCE_TEXT_DATA;
192 rc = diff_atomize_file(diff_data, cfg, f, *p, *size, diff_flags);
194 return got_error_set_errno(rc, "diff_atomize_file");
199 static const struct got_error *
200 blame_commit(struct got_blame *blame, struct got_object_id *id,
201 const char *path, struct got_repository *repo,
202 got_blame_cb cb, void *arg)
204 const struct got_error *err = NULL;
205 struct got_commit_object *commit = NULL, *pcommit = NULL;
206 struct got_object_qid *pid = NULL;
207 struct got_object_id *pblob_id = NULL;
208 struct got_blob_object *pblob = NULL;
209 struct diff_result *diff_result = NULL;
211 err = got_object_open_as_commit(&commit, repo, id);
215 pid = STAILQ_FIRST(got_object_commit_get_parent_ids(commit));
217 got_object_commit_close(commit);
221 err = got_object_open_as_commit(&pcommit, repo, &pid->id);
225 err = got_object_id_by_path(&pblob_id, repo, pcommit, path);
227 if (err->code == GOT_ERR_NO_TREE_ENTRY)
232 err = got_object_open_as_blob(&pblob, repo, pblob_id, 8192, blame->fd);
236 err = blame_prepare_file(blame->f1, &blame->map1, &blame->size1,
237 &blame->nlines1, &blame->line_offsets1, blame->data1,
242 diff_result = diff_main(blame->cfg, blame->data1, blame->data2);
243 if (diff_result == NULL) {
244 err = got_error_set_errno(ENOMEM, "malloc");
247 if (diff_result->rc != DIFF_RC_OK) {
248 err = got_error_set_errno(diff_result->rc, "diff");
251 if (diff_result->chunks.len > 0) {
252 if (blame->nlines1 > 0) {
253 blame->linemap1 = calloc(blame->nlines1,
254 sizeof(*blame->linemap1));
255 if (blame->linemap1 == NULL) {
256 err = got_error_from_errno("malloc");
260 err = blame_changes(blame, diff_result, commit, id, cb, arg);
264 err = cb(arg, blame->nlines, -1, commit, id);
267 diff_result_free(diff_result);
269 got_object_commit_close(commit);
271 got_object_commit_close(pcommit);
274 got_object_blob_close(pblob);
278 static const struct got_error *
279 blame_close(struct got_blame *blame)
281 const struct got_error *err = NULL;
283 diff_data_free(blame->data1);
285 diff_data_free(blame->data2);
288 if (munmap(blame->map1, blame->size1) == -1 && err == NULL)
289 err = got_error_from_errno("munmap");
292 if (munmap(blame->map2, blame->size2) == -1 && err == NULL)
293 err = got_error_from_errno("munmap");
296 free(blame->line_offsets1);
297 free(blame->line_offsets2);
298 free(blame->linemap1);
299 free(blame->linemap2);
306 atomize_file(struct diff_data *d, FILE *f, off_t filesize, int nlines,
309 int i, rc = DIFF_RC_OK;
310 int embedded_nul = 0;
312 ARRAYLIST_INIT(d->atoms, nlines);
314 for (i = 0; i < nlines; i++) {
315 struct diff_atom *atom;
316 off_t len, pos = line_offsets[i];
317 unsigned int hash = 0;
320 ARRAYLIST_ADD(atom, d->atoms);
327 len = line_offsets[i + 1] - pos;
329 len = filesize - pos;
331 if (fseeko(f, pos, SEEK_SET) == -1) {
335 for (j = 0; j < len; j++) {
339 rc = EIO; /* unexpected EOF */
345 hash = diff_atom_hash_update(hash, (unsigned char)c);
351 *atom = (struct diff_atom){
354 .at = NULL, /* atom data is not memory-mapped */
360 /* File are considered binary if they contain embedded '\0' bytes. */
362 d->atomizer_flags |= DIFF_ATOMIZER_FOUND_BINARY_DATA;
365 ARRAYLIST_FREE(d->atoms);
371 atomize_file_mmap(struct diff_data *d, unsigned char *p,
372 off_t filesize, int nlines, off_t *line_offsets)
374 int i, rc = DIFF_RC_OK;
375 int embedded_nul = 0;
377 ARRAYLIST_INIT(d->atoms, nlines);
379 for (i = 0; i < nlines; i++) {
380 struct diff_atom *atom;
381 off_t len, pos = line_offsets[i];
382 unsigned int hash = 0;
385 ARRAYLIST_ADD(atom, d->atoms);
392 len = line_offsets[i + 1] - pos;
394 len = filesize - pos;
396 for (j = 0; j < len; j++)
397 hash = diff_atom_hash_update(hash, p[pos + j]);
399 if (!embedded_nul && memchr(&p[pos], '\0', len) != NULL)
402 *atom = (struct diff_atom){
411 /* File are considered binary if they contain embedded '\0' bytes. */
413 d->atomizer_flags |= DIFF_ATOMIZER_FOUND_BINARY_DATA;
416 ARRAYLIST_FREE(d->atoms);
421 /* Implements diff_atomize_func_t */
423 blame_atomize_file(void *arg, struct diff_data *d)
425 struct got_blame *blame = arg;
427 if (d->f == blame->f1) {
429 return atomize_file_mmap(d, blame->map1,
430 blame->size1, blame->nlines1,
431 blame->line_offsets1);
433 return atomize_file(d, blame->f1, blame->size1,
434 blame->nlines1, blame->line_offsets1);
435 } else if (d->f == blame->f2) {
436 if (d->atoms.len > 0) {
437 /* Re-use data from previous commit. */
441 return atomize_file_mmap(d, blame->map2,
442 blame->size2, blame->nlines2,
443 blame->line_offsets2);
445 return atomize_file(d, blame->f2, blame->size2,
446 blame->nlines2, blame->line_offsets2);
452 static const struct got_error *
453 flip_files(struct got_blame *blame)
455 const struct got_error *err = NULL;
459 free(blame->line_offsets2);
460 blame->line_offsets2 = blame->line_offsets1;
461 blame->line_offsets1 = NULL;
463 free(blame->linemap2);
464 blame->linemap2 = blame->linemap1;
465 blame->linemap1 = NULL;
468 if (munmap(blame->map2, blame->size2) == -1)
469 return got_error_from_errno("munmap");
470 blame->map2 = blame->map1;
473 blame->size2 = blame->size1;
475 err = got_opentemp_truncate(blame->f2);
479 blame->f2 = blame->f1;
483 blame->nlines2 = blame->nlines1;
486 diff_data_free(blame->data2); /* does not free pointer itself */
487 memset(blame->data2, 0, sizeof(*blame->data2));
489 blame->data2 = blame->data1;
495 static const struct got_error *
496 blame_open(struct got_blame **blamep, const char *path,
497 struct got_object_id *start_commit_id, struct got_repository *repo,
498 enum got_diff_algorithm diff_algo, got_blame_cb cb, void *arg,
499 got_cancel_cb cancel_cb, void *cancel_arg,
500 int fd1, int fd2, FILE *f1, FILE *f2)
502 const struct got_error *err = NULL;
503 struct got_commit_object *start_commit = NULL, *last_commit = NULL;
504 struct got_object_id *obj_id = NULL;
505 struct got_blob_object *blob = NULL;
506 struct got_blame *blame = NULL;
507 struct got_object_id id;
508 int lineno, have_id = 0;
509 struct got_commit_graph *graph = NULL;
513 err = got_object_open_as_commit(&start_commit, repo, start_commit_id);
517 err = got_object_id_by_path(&obj_id, repo, start_commit, path);
521 err = got_object_open_as_blob(&blob, repo, obj_id, 8192, fd1);
525 blame = calloc(1, sizeof(*blame));
527 err = got_error_from_errno("calloc");
531 blame->data1 = calloc(1, sizeof(*blame->data1));
532 if (blame->data1 == NULL) {
533 err = got_error_from_errno("calloc");
536 blame->data2 = calloc(1, sizeof(*blame->data2));
537 if (blame->data2 == NULL) {
538 err = got_error_from_errno("calloc");
546 err = got_diff_get_config(&blame->cfg, diff_algo, blame_atomize_file,
551 err = blame_prepare_file(blame->f2, &blame->map2, &blame->size2,
552 &blame->nlines2, &blame->line_offsets2, blame->data2,
554 blame->nlines = blame->nlines2;
555 if (err || blame->nlines == 0)
558 got_object_blob_close(blob);
561 /* Don't include \n at EOF in the blame line count. */
562 if (blame->line_offsets2[blame->nlines - 1] == blame->size2)
565 blame->lines = calloc(blame->nlines, sizeof(*blame->lines));
566 if (blame->lines == NULL) {
567 err = got_error_from_errno("calloc");
571 blame->linemap2 = calloc(blame->nlines2, sizeof(*blame->linemap2));
572 if (blame->linemap2 == NULL) {
573 err = got_error_from_errno("calloc");
576 for (lineno = 0; lineno < blame->nlines2; lineno++)
577 blame->linemap2[lineno] = lineno;
579 err = got_commit_graph_open(&graph, path, 1);
583 err = got_commit_graph_iter_start(graph, start_commit_id, repo,
584 cancel_cb, cancel_arg);
588 err = got_commit_graph_iter_next(&id, graph, repo,
589 cancel_cb, cancel_arg);
591 if (err->code == GOT_ERR_ITER_COMPLETED) {
599 err = blame_commit(blame, &id, path, repo, cb, arg);
601 if (err->code == GOT_ERR_ITER_COMPLETED)
605 if (blame->nannotated == blame->nlines)
608 err = flip_files(blame);
613 if (have_id && blame->nannotated < blame->nlines) {
614 /* Annotate remaining non-annotated lines with last commit. */
615 err = got_object_open_as_commit(&last_commit, repo, &id);
618 for (lineno = 0; lineno < blame->nlines; lineno++) {
619 err = annotate_line(blame, lineno, last_commit, &id,
628 got_commit_graph_close(graph);
631 got_object_blob_close(blob);
633 got_object_commit_close(start_commit);
635 got_object_commit_close(last_commit);
645 const struct got_error *
646 got_blame(const char *path, struct got_object_id *commit_id,
647 struct got_repository *repo, enum got_diff_algorithm diff_algo,
648 got_blame_cb cb, void *arg, got_cancel_cb cancel_cb, void* cancel_arg,
649 int fd1, int fd2, FILE *f1, FILE *f2)
651 const struct got_error *err = NULL, *close_err = NULL;
652 struct got_blame *blame;
655 if (asprintf(&abspath, "%s%s", path[0] == '/' ? "" : "/", path) == -1)
656 return got_error_from_errno2("asprintf", path);
658 err = blame_open(&blame, abspath, commit_id, repo, diff_algo,
659 cb, arg, cancel_cb, cancel_arg, fd1, fd2, f1, f2);
662 close_err = blame_close(blame);
663 return err ? err : close_err;