afc75fe7314e6d23f4c9c36138eede77064d804c
1/*
2 * "git rebase" builtin command
3 *
4 * Copyright (c) 2018 Pratik Karki
5 */
6#include "builtin.h"
8#include "run-command.h"
9#include "exec-cmd.h"
10#include "argv-array.h"
11#include "dir.h"
12#include "packfile.h"
13#include "refs.h"
14#include "quote.h"
15#include "config.h"
16#include "cache-tree.h"
17#include "unpack-trees.h"
18#include "lockfile.h"
19#include "parse-options.h"
20#include "commit.h"
21#include "diff.h"
22#include "wt-status.h"
23#include "revision.h"
24static char const * const builtin_rebase_usage[] = {
26 N_("git rebase [-i] [options] [--exec <cmd>] [--onto <newbase>] "
27 "[<upstream>] [<branch>]"),
28 N_("git rebase [-i] [options] [--exec <cmd>] [--onto <newbase>] "
29 "--root [<branch>]"),
30 N_("git rebase --continue | --abort | --skip | --edit-todo"),
31 NULL
32};
33static GIT_PATH_FUNC(apply_dir, "rebase-apply")
35static GIT_PATH_FUNC(merge_dir, "rebase-merge")
36enum rebase_type {
38 REBASE_UNSPECIFIED = -1,
39 REBASE_AM,
40 REBASE_MERGE,
41 REBASE_INTERACTIVE,
42 REBASE_PRESERVE_MERGES
43};
44static int use_builtin_rebase(void)
46{
47 struct child_process cp = CHILD_PROCESS_INIT;
48 struct strbuf out = STRBUF_INIT;
49 int ret;
50 argv_array_pushl(&cp.args,
52 "config", "--bool", "rebase.usebuiltin", NULL);
53 cp.git_cmd = 1;
54 if (capture_command(&cp, &out, 6)) {
55 strbuf_release(&out);
56 return 0;
57 }
58 strbuf_trim(&out);
60 ret = !strcmp("true", out.buf);
61 strbuf_release(&out);
62 return ret;
63}
64static int apply_autostash(void)
66{
67 warning("TODO");
68 return 0;
69}
70struct rebase_options {
72 enum rebase_type type;
73 const char *state_dir;
74 struct commit *upstream;
75 const char *upstream_name;
76 const char *upstream_arg;
77 char *head_name;
78 struct object_id orig_head;
79 struct commit *onto;
80 const char *onto_name;
81 const char *revisions;
82 int root;
83 struct commit *restrict_revision;
84 int dont_finish_rebase;
85 enum {
86 REBASE_NO_QUIET = 1<<0,
87 REBASE_VERBOSE = 1<<1,
88 REBASE_DIFFSTAT = 1<<2,
89 REBASE_FORCE = 1<<3,
90 REBASE_INTERACTIVE_EXPLICIT = 1<<4,
91 } flags;
92 struct strbuf git_am_opt;
93};
94static int is_interactive(struct rebase_options *opts)
96{
97 return opts->type == REBASE_INTERACTIVE ||
98 opts->type == REBASE_PRESERVE_MERGES;
99}
100/* Returns the filename prefixed by the state_dir */
102static const char *state_dir_path(const char *filename, struct rebase_options *opts)
103{
104 static struct strbuf path = STRBUF_INIT;
105 static size_t prefix_len;
106 if (!prefix_len) {
108 strbuf_addf(&path, "%s/", opts->state_dir);
109 prefix_len = path.len;
110 }
111 strbuf_setlen(&path, prefix_len);
113 strbuf_addstr(&path, filename);
114 return path.buf;
115}
116static int finish_rebase(struct rebase_options *opts)
118{
119 struct strbuf dir = STRBUF_INIT;
120 const char *argv_gc_auto[] = { "gc", "--auto", NULL };
121 delete_ref(NULL, "REBASE_HEAD", NULL, REF_NO_DEREF);
123 apply_autostash();
124 close_all_packs(the_repository->objects);
125 /*
126 * We ignore errors in 'gc --auto', since the
127 * user should see them.
128 */
129 run_command_v_opt(argv_gc_auto, RUN_GIT_CMD);
130 strbuf_addstr(&dir, opts->state_dir);
131 remove_dir_recursively(&dir, 0);
132 strbuf_release(&dir);
133 return 0;
135}
136static struct commit *peel_committish(const char *name)
138{
139 struct object *obj;
140 struct object_id oid;
141 if (get_oid(name, &oid))
143 return NULL;
144 obj = parse_object(the_repository, &oid);
145 return (struct commit *)peel_to_type(name, 0, obj, OBJ_COMMIT);
146}
147static void add_var(struct strbuf *buf, const char *name, const char *value)
149{
150 if (!value)
151 strbuf_addf(buf, "unset %s; ", name);
152 else {
153 strbuf_addf(buf, "%s=", name);
154 sq_quote_buf(buf, value);
155 strbuf_addstr(buf, "; ");
156 }
157}
158static int run_specific_rebase(struct rebase_options *opts)
160{
161 const char *argv[] = { NULL, NULL };
162 struct strbuf script_snippet = STRBUF_INIT;
163 int status;
164 const char *backend, *backend_func;
165 add_var(&script_snippet, "GIT_DIR", absolute_path(get_git_dir()));
167 add_var(&script_snippet, "state_dir", opts->state_dir);
168 add_var(&script_snippet, "upstream_name", opts->upstream_name);
170 add_var(&script_snippet, "upstream",
171 oid_to_hex(&opts->upstream->object.oid));
172 add_var(&script_snippet, "head_name",
173 opts->head_name ? opts->head_name : "detached HEAD");
174 add_var(&script_snippet, "orig_head", oid_to_hex(&opts->orig_head));
175 add_var(&script_snippet, "onto", oid_to_hex(&opts->onto->object.oid));
176 add_var(&script_snippet, "onto_name", opts->onto_name);
177 add_var(&script_snippet, "revisions", opts->revisions);
178 add_var(&script_snippet, "restrict_revision", opts->restrict_revision ?
179 oid_to_hex(&opts->restrict_revision->object.oid) : NULL);
180 add_var(&script_snippet, "GIT_QUIET",
181 opts->flags & REBASE_NO_QUIET ? "" : "t");
182 add_var(&script_snippet, "git_am_opt", opts->git_am_opt.buf);
183 add_var(&script_snippet, "verbose",
184 opts->flags & REBASE_VERBOSE ? "t" : "");
185 add_var(&script_snippet, "diffstat",
186 opts->flags & REBASE_DIFFSTAT ? "t" : "");
187 add_var(&script_snippet, "force_rebase",
188 opts->flags & REBASE_FORCE ? "t" : "");
189 switch (opts->type) {
191 case REBASE_AM:
192 backend = "git-rebase--am";
193 backend_func = "git_rebase__am";
194 break;
195 case REBASE_INTERACTIVE:
196 backend = "git-rebase--interactive";
197 backend_func = "git_rebase__interactive";
198 break;
199 case REBASE_MERGE:
200 backend = "git-rebase--merge";
201 backend_func = "git_rebase__merge";
202 break;
203 case REBASE_PRESERVE_MERGES:
204 backend = "git-rebase--preserve-merges";
205 backend_func = "git_rebase__preserve_merges";
206 break;
207 default:
208 BUG("Unhandled rebase type %d", opts->type);
209 break;
210 }
211 strbuf_addf(&script_snippet,
213 ". git-sh-setup && . git-rebase--common &&"
214 " . %s && %s", backend, backend_func);
215 argv[0] = script_snippet.buf;
216 status = run_command_v_opt(argv, RUN_USING_SHELL);
218 if (opts->dont_finish_rebase)
219 ; /* do nothing */
220 else if (status == 0) {
221 if (!file_exists(state_dir_path("stopped-sha", opts)))
222 finish_rebase(opts);
223 } else if (status == 2) {
224 struct strbuf dir = STRBUF_INIT;
225 apply_autostash();
227 strbuf_addstr(&dir, opts->state_dir);
228 remove_dir_recursively(&dir, 0);
229 strbuf_release(&dir);
230 die("Nothing to do");
231 }
232 strbuf_release(&script_snippet);
234 return status ? -1 : 0;
236}
237#define GIT_REFLOG_ACTION_ENVIRONMENT "GIT_REFLOG_ACTION"
239static int reset_head(struct object_id *oid, const char *action,
241 const char *switch_to_branch, int detach_head)
242{
243 struct object_id head_oid;
244 struct tree_desc desc;
245 struct lock_file lock = LOCK_INIT;
246 struct unpack_trees_options unpack_tree_opts;
247 struct tree *tree;
248 const char *reflog_action;
249 struct strbuf msg = STRBUF_INIT;
250 size_t prefix_len;
251 struct object_id *orig = NULL, oid_orig,
252 *old_orig = NULL, oid_old_orig;
253 int ret = 0;
254 if (switch_to_branch && !starts_with(switch_to_branch, "refs/"))
256 BUG("Not a fully qualified branch: '%s'", switch_to_branch);
257 if (hold_locked_index(&lock, LOCK_REPORT_ON_ERROR) < 0)
259 return -1;
260 if (!oid) {
262 if (get_oid("HEAD", &head_oid)) {
263 rollback_lock_file(&lock);
264 return error(_("could not determine HEAD revision"));
265 }
266 oid = &head_oid;
267 }
268 memset(&unpack_tree_opts, 0, sizeof(unpack_tree_opts));
270 setup_unpack_trees_porcelain(&unpack_tree_opts, action);
271 unpack_tree_opts.head_idx = 1;
272 unpack_tree_opts.src_index = the_repository->index;
273 unpack_tree_opts.dst_index = the_repository->index;
274 unpack_tree_opts.fn = oneway_merge;
275 unpack_tree_opts.update = 1;
276 unpack_tree_opts.merge = 1;
277 if (!detach_head)
278 unpack_tree_opts.reset = 1;
279 if (read_index_unmerged(the_repository->index) < 0) {
281 rollback_lock_file(&lock);
282 return error(_("could not read index"));
283 }
284 if (!fill_tree_descriptor(&desc, oid)) {
286 error(_("failed to find tree of %s"), oid_to_hex(oid));
287 rollback_lock_file(&lock);
288 free((void *)desc.buffer);
289 return -1;
290 }
291 if (unpack_trees(1, &desc, &unpack_tree_opts)) {
293 rollback_lock_file(&lock);
294 free((void *)desc.buffer);
295 return -1;
296 }
297 tree = parse_tree_indirect(oid);
299 prime_cache_tree(the_repository->index, tree);
300 if (write_locked_index(the_repository->index, &lock, COMMIT_LOCK) < 0)
302 ret = error(_("could not write index"));
303 free((void *)desc.buffer);
304 if (ret)
306 return ret;
307 reflog_action = getenv(GIT_REFLOG_ACTION_ENVIRONMENT);
309 strbuf_addf(&msg, "%s: ", reflog_action ? reflog_action : "rebase");
310 prefix_len = msg.len;
311 if (!get_oid("ORIG_HEAD", &oid_old_orig))
313 old_orig = &oid_old_orig;
314 if (!get_oid("HEAD", &oid_orig)) {
315 orig = &oid_orig;
316 strbuf_addstr(&msg, "updating ORIG_HEAD");
317 update_ref(msg.buf, "ORIG_HEAD", orig, old_orig, 0,
318 UPDATE_REFS_MSG_ON_ERR);
319 } else if (old_orig)
320 delete_ref(NULL, "ORIG_HEAD", old_orig, 0);
321 strbuf_setlen(&msg, prefix_len);
322 strbuf_addstr(&msg, "updating HEAD");
323 if (!switch_to_branch)
324 ret = update_ref(msg.buf, "HEAD", oid, orig, REF_NO_DEREF,
325 UPDATE_REFS_MSG_ON_ERR);
326 else {
327 ret = create_symref("HEAD", switch_to_branch, msg.buf);
328 if (!ret)
329 ret = update_ref(msg.buf, "HEAD", oid, NULL, 0,
330 UPDATE_REFS_MSG_ON_ERR);
331 }
332 strbuf_release(&msg);
334 return ret;
335}
336static int rebase_config(const char *var, const char *value, void *data)
338{
339 struct rebase_options *opts = data;
340 if (!strcmp(var, "rebase.stat")) {
342 if (git_config_bool(var, value))
343 opts->flags |= REBASE_DIFFSTAT;
344 else
345 opts->flags &= !REBASE_DIFFSTAT;
346 return 0;
347 }
348 return git_default_config(var, value, data);
350}
351/*
353 * Determines whether the commits in from..to are linear, i.e. contain
354 * no merge commits. This function *expects* `from` to be an ancestor of
355 * `to`.
356 */
357static int is_linear_history(struct commit *from, struct commit *to)
358{
359 while (to && to != from) {
360 parse_commit(to);
361 if (!to->parents)
362 return 1;
363 if (to->parents->next)
364 return 0;
365 to = to->parents->item;
366 }
367 return 1;
368}
369static int can_fast_forward(struct commit *onto, struct object_id *head_oid,
371 struct object_id *merge_base)
372{
373 struct commit *head = lookup_commit(the_repository, head_oid);
374 struct commit_list *merge_bases;
375 int res;
376 if (!head)
378 return 0;
379 merge_bases = get_merge_bases(onto, head);
381 if (merge_bases && !merge_bases->next) {
382 oidcpy(merge_base, &merge_bases->item->object.oid);
383 res = !oidcmp(merge_base, &onto->object.oid);
384 } else {
385 oidcpy(merge_base, &null_oid);
386 res = 0;
387 }
388 free_commit_list(merge_bases);
389 return res && is_linear_history(onto, head);
390}
391int cmd_rebase(int argc, const char **argv, const char *prefix)
393{
394 struct rebase_options options = {
395 .type = REBASE_UNSPECIFIED,
396 .flags = REBASE_NO_QUIET,
397 .git_am_opt = STRBUF_INIT,
398 };
399 const char *branch_name;
400 int ret, flags, in_progress = 0;
401 int ok_to_skip_pre_rebase = 0;
402 struct strbuf msg = STRBUF_INIT;
403 struct strbuf revisions = STRBUF_INIT;
404 struct strbuf buf = STRBUF_INIT;
405 struct object_id merge_base;
406 struct option builtin_rebase_options[] = {
407 OPT_STRING(0, "onto", &options.onto_name,
408 N_("revision"),
409 N_("rebase onto given branch instead of upstream")),
410 OPT_BOOL(0, "no-verify", &ok_to_skip_pre_rebase,
411 N_("allow pre-rebase hook to run")),
412 OPT_NEGBIT('q', "quiet", &options.flags,
413 N_("be quiet. implies --no-stat"),
414 REBASE_NO_QUIET| REBASE_VERBOSE | REBASE_DIFFSTAT),
415 OPT_BIT('v', "verbose", &options.flags,
416 N_("display a diffstat of what changed upstream"),
417 REBASE_NO_QUIET | REBASE_VERBOSE | REBASE_DIFFSTAT),
418 {OPTION_NEGBIT, 'n', "no-stat", &options.flags, NULL,
419 N_("do not show diffstat of what changed upstream"),
420 PARSE_OPT_NOARG, NULL, REBASE_DIFFSTAT },
421 OPT_BIT('f', "force-rebase", &options.flags,
422 N_("cherry-pick all commits, even if unchanged"),
423 REBASE_FORCE),
424 OPT_BIT(0, "no-ff", &options.flags,
425 N_("cherry-pick all commits, even if unchanged"),
426 REBASE_FORCE),
427 OPT_END(),
428 };
429 /*
431 * NEEDSWORK: Once the builtin rebase has been tested enough
432 * and git-legacy-rebase.sh is retired to contrib/, this preamble
433 * can be removed.
434 */
435 if (!use_builtin_rebase()) {
437 const char *path = mkpath("%s/git-legacy-rebase",
438 git_exec_path());
439 if (sane_execvp(path, (char **)argv) < 0)
441 die_errno(_("could not exec %s"), path);
442 else
443 BUG("sane_execvp() returned???");
444 }
445 if (argc == 2 && !strcmp(argv[1], "-h"))
447 usage_with_options(builtin_rebase_usage,
448 builtin_rebase_options);
449 prefix = setup_git_directory();
451 trace_repo_setup(prefix);
452 setup_work_tree();
453 git_config(rebase_config, &options);
455 if (is_directory(apply_dir())) {
457 options.type = REBASE_AM;
458 options.state_dir = apply_dir();
459 } else if (is_directory(merge_dir())) {
460 strbuf_reset(&buf);
461 strbuf_addf(&buf, "%s/rewritten", merge_dir());
462 if (is_directory(buf.buf)) {
463 options.type = REBASE_PRESERVE_MERGES;
464 options.flags |= REBASE_INTERACTIVE_EXPLICIT;
465 } else {
466 strbuf_reset(&buf);
467 strbuf_addf(&buf, "%s/interactive", merge_dir());
468 if(file_exists(buf.buf)) {
469 options.type = REBASE_INTERACTIVE;
470 options.flags |= REBASE_INTERACTIVE_EXPLICIT;
471 } else
472 options.type = REBASE_MERGE;
473 }
474 options.state_dir = merge_dir();
475 }
476 if (options.type != REBASE_UNSPECIFIED)
478 in_progress = 1;
479 argc = parse_options(argc, argv, prefix,
481 builtin_rebase_options,
482 builtin_rebase_usage, 0);
483 if (argc > 2)
485 usage_with_options(builtin_rebase_usage,
486 builtin_rebase_options);
487 /* Make sure no rebase is in progress */
489 if (in_progress) {
490 const char *last_slash = strrchr(options.state_dir, '/');
491 const char *state_dir_base =
492 last_slash ? last_slash + 1 : options.state_dir;
493 const char *cmd_live_rebase =
494 "git rebase (--continue | --abort | --skip)";
495 strbuf_reset(&buf);
496 strbuf_addf(&buf, "rm -fr \"%s\"", options.state_dir);
497 die(_("It seems that there is already a %s directory, and\n"
498 "I wonder if you are in the middle of another rebase. "
499 "If that is the\n"
500 "case, please try\n\t%s\n"
501 "If that is not the case, please\n\t%s\n"
502 "and run me again. I am stopping in case you still "
503 "have something\n"
504 "valuable there.\n"),
505 state_dir_base, cmd_live_rebase, buf.buf);
506 }
507 if (!(options.flags & REBASE_NO_QUIET))
509 strbuf_addstr(&options.git_am_opt, " -q");
510 switch (options.type) {
512 case REBASE_MERGE:
513 case REBASE_INTERACTIVE:
514 case REBASE_PRESERVE_MERGES:
515 options.state_dir = merge_dir();
516 break;
517 case REBASE_AM:
518 options.state_dir = apply_dir();
519 break;
520 default:
521 /* the default rebase backend is `--am` */
522 options.type = REBASE_AM;
523 options.state_dir = apply_dir();
524 break;
525 }
526 if (!options.root) {
528 if (argc < 1)
529 die("TODO: handle @{upstream}");
530 else {
531 options.upstream_name = argv[0];
532 argc--;
533 argv++;
534 if (!strcmp(options.upstream_name, "-"))
535 options.upstream_name = "@{-1}";
536 }
537 options.upstream = peel_committish(options.upstream_name);
538 if (!options.upstream)
539 die(_("invalid upstream '%s'"), options.upstream_name);
540 options.upstream_arg = options.upstream_name;
541 } else
542 die("TODO: upstream for --root");
543 /* Make sure the branch to rebase onto is valid. */
545 if (!options.onto_name)
546 options.onto_name = options.upstream_name;
547 if (strstr(options.onto_name, "...")) {
548 if (get_oid_mb(options.onto_name, &merge_base) < 0)
549 die(_("'%s': need exactly one merge base"),
550 options.onto_name);
551 options.onto = lookup_commit_or_die(&merge_base,
552 options.onto_name);
553 } else {
554 options.onto = peel_committish(options.onto_name);
555 if (!options.onto)
556 die(_("Does not point to a valid commit '%s'"),
557 options.onto_name);
558 }
559 /*
561 * If the branch to rebase is given, that is the branch we will rebase
562 * branch_name -- branch/commit being rebased, or
563 * HEAD (already detached)
564 * orig_head -- commit object name of tip of the branch before rebasing
565 * head_name -- refs/heads/<that-branch> or NULL (detached HEAD)
566 */
567 if (argc > 0)
568 die("TODO: handle switch_to");
569 else {
570 /* Do not need to switch branches, we are already on it. */
571 options.head_name =
572 xstrdup_or_null(resolve_ref_unsafe("HEAD", 0, NULL,
573 &flags));
574 if (!options.head_name)
575 die(_("No such ref: %s"), "HEAD");
576 if (flags & REF_ISSYMREF) {
577 if (!skip_prefix(options.head_name,
578 "refs/heads/", &branch_name))
579 branch_name = options.head_name;
580 } else {
582 free(options.head_name);
583 options.head_name = NULL;
584 branch_name = "HEAD";
585 }
586 if (get_oid("HEAD", &options.orig_head))
587 die(_("Could not resolve HEAD to a revision"));
588 }
589 if (read_index(the_repository->index) < 0)
591 die(_("could not read index"));
592 if (require_clean_work_tree("rebase",
594 _("Please commit or stash them."), 1, 1)) {
595 ret = 1;
596 goto cleanup;
597 }
598 /*
600 * Now we are rebasing commits upstream..orig_head (or with --root,
601 * everything leading up to orig_head) on top of onto.
602 */
603 /*
605 * Check if we are already based on onto with linear history,
606 * but this should be done only when upstream and onto are the same
607 * and if this is not an interactive rebase.
608 */
609 if (can_fast_forward(options.onto, &options.orig_head, &merge_base) &&
610 !is_interactive(&options) && !options.restrict_revision &&
611 !oidcmp(&options.upstream->object.oid, &options.onto->object.oid)) {
612 int flag;
613 if (!(options.flags & REBASE_FORCE)) {
615 if (!(options.flags & REBASE_NO_QUIET))
616 ; /* be quiet */
617 else if (!strcmp(branch_name, "HEAD") &&
618 resolve_ref_unsafe("HEAD", 0, NULL, &flag))
619 puts(_("HEAD is up to date."));
620 else
621 printf(_("Current branch %s is up to date.\n"),
622 branch_name);
623 ret = !!finish_rebase(&options);
624 goto cleanup;
625 } else if (!(options.flags & REBASE_NO_QUIET))
626 ; /* be quiet */
627 else if (!strcmp(branch_name, "HEAD") &&
628 resolve_ref_unsafe("HEAD", 0, NULL, &flag))
629 puts(_("HEAD is up to date, rebase forced."));
630 else
631 printf(_("Current branch %s is up to date, rebase "
632 "forced.\n"), branch_name);
633 }
634 /* If a hook exists, give it a chance to interrupt*/
636 if (!ok_to_skip_pre_rebase &&
637 run_hook_le(NULL, "pre-rebase", options.upstream_arg,
638 argc ? argv[0] : NULL, NULL))
639 die(_("The pre-rebase hook refused to rebase."));
640 if (options.flags & REBASE_DIFFSTAT) {
642 struct diff_options opts;
643 if (options.flags & REBASE_VERBOSE)
645 printf(_("Changes from %s to %s:\n"),
646 oid_to_hex(&merge_base),
647 oid_to_hex(&options.onto->object.oid));
648 /* We want color (if set), but no pager */
650 diff_setup(&opts);
651 opts.stat_width = -1; /* use full terminal width */
652 opts.stat_graph_width = -1; /* respect statGraphWidth config */
653 opts.output_format |=
654 DIFF_FORMAT_SUMMARY | DIFF_FORMAT_DIFFSTAT;
655 opts.detect_rename = DIFF_DETECT_RENAME;
656 diff_setup_done(&opts);
657 diff_tree_oid(&merge_base, &options.onto->object.oid,
658 "", &opts);
659 diffcore_std(&opts);
660 diff_flush(&opts);
661 }
662 /* Detach HEAD and reset the tree */
664 if (options.flags & REBASE_NO_QUIET)
665 printf(_("First, rewinding head to replay your work on top of "
666 "it...\n"));
667 strbuf_addf(&msg, "rebase: checkout %s", options.onto_name);
669 if (reset_head(&options.onto->object.oid, "checkout", NULL, 1))
670 die(_("Could not detach HEAD"));
671 strbuf_release(&msg);
672 strbuf_addf(&revisions, "%s..%s",
674 options.root ? oid_to_hex(&options.onto->object.oid) :
675 (options.restrict_revision ?
676 oid_to_hex(&options.restrict_revision->object.oid) :
677 oid_to_hex(&options.upstream->object.oid)),
678 oid_to_hex(&options.orig_head));
679 options.revisions = revisions.buf;
681 ret = !!run_specific_rebase(&options);
683cleanup:
685 strbuf_release(&revisions);
686 free(options.head_name);
687 return ret;
688}