revert: use run_command_v_opt() instead of execv_git_cmd()
[git/git.git] / builtin / revert.c
CommitLineData
9509af68
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1#include "cache.h"
2#include "builtin.h"
3#include "object.h"
4#include "commit.h"
5#include "tag.h"
6#include "wt-status.h"
7#include "run-command.h"
8#include "exec_cmd.h"
9#include "utf8.h"
f8103794 10#include "parse-options.h"
45525bd0 11#include "cache-tree.h"
0f2d4476
JK
12#include "diff.h"
13#include "revision.h"
aa1a0111 14#include "rerere.h"
6eb1b437 15#include "merge-recursive.h"
c62f6ec3 16#include "refs.h"
9509af68
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17
18/*
19 * This implements the builtins revert and cherry-pick.
20 *
21 * Copyright (c) 2007 Johannes E. Schindelin
22 *
23 * Based on git-revert.sh, which is
24 *
25 * Copyright (c) 2005 Linus Torvalds
26 * Copyright (c) 2005 Junio C Hamano
27 */
28
f8103794 29static const char * const revert_usage[] = {
1b1dd23f 30 "git revert [options] <commit-ish>",
f8103794
PH
31 NULL
32};
9509af68 33
f8103794 34static const char * const cherry_pick_usage[] = {
1b1dd23f 35 "git cherry-pick [options] <commit-ish>",
f8103794
PH
36 NULL
37};
9509af68 38
c62f6ec3 39static int edit, no_replay, no_commit, mainline, signoff, allow_ff;
4175e9e3 40static enum { REVERT, CHERRY_PICK } action;
9509af68 41static struct commit *commit;
97915544 42static const char *commit_name;
cb6020bb 43static int allow_rerere_auto;
9509af68
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44
45static const char *me;
91e52598 46static const char *strategy;
9509af68
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47
48#define GIT_REFLOG_ACTION "GIT_REFLOG_ACTION"
49
d6856540
JN
50static char *get_encoding(const char *message);
51
f8103794 52static void parse_args(int argc, const char **argv)
9509af68 53{
f8103794
PH
54 const char * const * usage_str =
55 action == REVERT ? revert_usage : cherry_pick_usage;
9509af68 56 unsigned char sha1[20];
f8103794
PH
57 int noop;
58 struct option options[] = {
59 OPT_BOOLEAN('n', "no-commit", &no_commit, "don't automatically commit"),
60 OPT_BOOLEAN('e', "edit", &edit, "edit the commit message"),
f8103794 61 OPT_BOOLEAN('r', NULL, &noop, "no-op (backward compatibility)"),
cfd9c277 62 OPT_BOOLEAN('s', "signoff", &signoff, "add Signed-off-by:"),
02273fdb 63 OPT_INTEGER('m', "mainline", &mainline, "parent number"),
cb6020bb 64 OPT_RERERE_AUTOUPDATE(&allow_rerere_auto),
91e52598 65 OPT_STRING(0, "strategy", &strategy, "strategy", "merge strategy"),
f8103794 66 OPT_END(),
c62f6ec3
JH
67 OPT_END(),
68 OPT_END(),
f8103794
PH
69 };
70
c62f6ec3
JH
71 if (action == CHERRY_PICK) {
72 struct option cp_extra[] = {
831244bd 73 OPT_BOOLEAN('x', NULL, &no_replay, "append commit name"),
c62f6ec3
JH
74 OPT_BOOLEAN(0, "ff", &allow_ff, "allow fast-forward"),
75 OPT_END(),
76 };
77 if (parse_options_concat(options, ARRAY_SIZE(options), cp_extra))
78 die("program error");
79 }
80
37782920 81 if (parse_options(argc, argv, NULL, options, usage_str, 0) != 1)
f8103794 82 usage_with_options(usage_str, options);
9509af68 83
97915544
JK
84 commit_name = argv[0];
85 if (get_sha1(commit_name, sha1))
86 die ("Cannot find '%s'", commit_name);
dd9314cc 87 commit = lookup_commit_reference(sha1);
9509af68 88 if (!commit)
dd9314cc 89 exit(1);
9509af68
JS
90}
91
d6856540
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92struct commit_message {
93 char *parent_label;
94 const char *label;
95 const char *subject;
96 char *reencoded_message;
97 const char *message;
98};
99
100static int get_message(const char *raw_message, struct commit_message *out)
9509af68 101{
d6856540
JN
102 const char *encoding;
103 const char *p, *abbrev, *eol;
104 char *q;
9509af68
JS
105 int abbrev_len, oneline_len;
106
d6856540
JN
107 if (!raw_message)
108 return -1;
109 encoding = get_encoding(raw_message);
110 if (!encoding)
111 encoding = "UTF-8";
112 if (!git_commit_encoding)
113 git_commit_encoding = "UTF-8";
43acff34
JN
114
115 out->reencoded_message = NULL;
116 out->message = raw_message;
117 if (strcmp(encoding, git_commit_encoding))
118 out->reencoded_message = reencode_string(raw_message,
119 git_commit_encoding, encoding);
120 if (out->reencoded_message)
d6856540
JN
121 out->message = out->reencoded_message;
122
123 abbrev = find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV);
124 abbrev_len = strlen(abbrev);
125
126 /* Find beginning and end of commit subject. */
127 p = out->message;
9509af68
JS
128 while (*p && (*p != '\n' || p[1] != '\n'))
129 p++;
9509af68
JS
130 if (*p) {
131 p += 2;
132 for (eol = p + 1; *eol && *eol != '\n'; eol++)
133 ; /* do nothing */
134 } else
135 eol = p;
9509af68 136 oneline_len = eol - p;
d6856540
JN
137
138 out->parent_label = xmalloc(strlen("parent of ") + abbrev_len +
139 strlen("... ") + oneline_len + 1);
140 q = out->parent_label;
141 q = mempcpy(q, "parent of ", strlen("parent of "));
142 out->label = q;
143 q = mempcpy(q, abbrev, abbrev_len);
144 q = mempcpy(q, "... ", strlen("... "));
145 out->subject = q;
146 q = mempcpy(q, p, oneline_len);
147 *q = '\0';
148 return 0;
149}
150
151static void free_message(struct commit_message *msg)
152{
153 free(msg->parent_label);
154 free(msg->reencoded_message);
9509af68
JS
155}
156
52fae7de 157static char *get_encoding(const char *message)
9509af68
JS
158{
159 const char *p = message, *eol;
160
161 if (!p)
162 die ("Could not read commit message of %s",
163 sha1_to_hex(commit->object.sha1));
164 while (*p && *p != '\n') {
165 for (eol = p + 1; *eol && *eol != '\n'; eol++)
166 ; /* do nothing */
167 if (!prefixcmp(p, "encoding ")) {
168 char *result = xmalloc(eol - 8 - p);
169 strlcpy(result, p + 9, eol - 8 - p);
170 return result;
171 }
172 p = eol;
173 if (*p == '\n')
174 p++;
175 }
176 return NULL;
177}
178
bc84a7fb 179static void add_message_to_msg(struct strbuf *msgbuf, const char *message)
9509af68
JS
180{
181 const char *p = message;
182 while (*p && (*p != '\n' || p[1] != '\n'))
183 p++;
184
185 if (!*p)
bc84a7fb 186 strbuf_addstr(msgbuf, sha1_to_hex(commit->object.sha1));
9509af68
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187
188 p += 2;
bc84a7fb 189 strbuf_addstr(msgbuf, p);
9509af68
JS
190}
191
192static void set_author_ident_env(const char *message)
193{
194 const char *p = message;
195 if (!p)
196 die ("Could not read commit message of %s",
197 sha1_to_hex(commit->object.sha1));
198 while (*p && *p != '\n') {
199 const char *eol;
200
201 for (eol = p; *eol && *eol != '\n'; eol++)
202 ; /* do nothing */
203 if (!prefixcmp(p, "author ")) {
204 char *line, *pend, *email, *timestamp;
205
206 p += 7;
182af834 207 line = xmemdupz(p, eol - p);
9509af68
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208 email = strchr(line, '<');
209 if (!email)
210 die ("Could not extract author email from %s",
211 sha1_to_hex(commit->object.sha1));
212 if (email == line)
213 pend = line;
214 else
215 for (pend = email; pend != line + 1 &&
216 isspace(pend[-1]); pend--);
217 ; /* do nothing */
218 *pend = '\0';
219 email++;
220 timestamp = strchr(email, '>');
221 if (!timestamp)
1e5f7add 222 die ("Could not extract author time from %s",
9509af68
JS
223 sha1_to_hex(commit->object.sha1));
224 *timestamp = '\0';
225 for (timestamp++; *timestamp && isspace(*timestamp);
226 timestamp++)
227 ; /* do nothing */
228 setenv("GIT_AUTHOR_NAME", line, 1);
229 setenv("GIT_AUTHOR_EMAIL", email, 1);
230 setenv("GIT_AUTHOR_DATE", timestamp, 1);
231 free(line);
232 return;
233 }
234 p = eol;
235 if (*p == '\n')
236 p++;
237 }
238 die ("No author information found in %s",
239 sha1_to_hex(commit->object.sha1));
240}
241
97915544 242static char *help_msg(const char *name)
804c7174 243{
08565bdb 244 struct strbuf helpbuf = STRBUF_INIT;
804c7174
WC
245 char *msg = getenv("GIT_CHERRY_PICK_HELP");
246
247 if (msg)
248 return msg;
249
08565bdb 250 strbuf_addstr(&helpbuf, " After resolving the conflicts,\n"
6e359978 251 "mark the corrected paths with 'git add <paths>' or 'git rm <paths>'\n"
4d128884 252 "and commit the result");
804c7174
WC
253
254 if (action == CHERRY_PICK) {
4d128884
JK
255 strbuf_addf(&helpbuf, " with: \n"
256 "\n"
257 " git commit -c %s\n",
97915544 258 name);
804c7174 259 }
4d128884
JK
260 else
261 strbuf_addch(&helpbuf, '.');
08565bdb 262 return strbuf_detach(&helpbuf, NULL);
804c7174
WC
263}
264
bc84a7fb
CC
265static void write_message(struct strbuf *msgbuf, const char *filename)
266{
267 static struct lock_file msg_file;
268
269 int msg_fd = hold_lock_file_for_update(&msg_file, filename,
270 LOCK_DIE_ON_ERROR);
271 if (write_in_full(msg_fd, msgbuf->buf, msgbuf->len) < 0)
272 die_errno("Could not write to %s.", filename);
273 strbuf_release(msgbuf);
274 if (commit_lock_file(&msg_file) < 0)
275 die("Error wrapping up %s", filename);
276}
277
6eb1b437
MV
278static struct tree *empty_tree(void)
279{
280 struct tree *tree = xcalloc(1, sizeof(struct tree));
281
282 tree->object.parsed = 1;
283 tree->object.type = OBJ_TREE;
284 pretend_sha1_file(NULL, 0, OBJ_TREE, tree->object.sha1);
285 return tree;
286}
287
d38a30df
MM
288static NORETURN void die_dirty_index(const char *me)
289{
290 if (read_cache_unmerged()) {
291 die_resolve_conflict(me);
292 } else {
293 if (advice_commit_before_merge)
294 die("Your local changes would be overwritten by %s.\n"
295 "Please, commit your changes or stash them to proceed.", me);
296 else
297 die("Your local changes would be overwritten by %s.\n", me);
298 }
299}
300
c62f6ec3
JH
301static int fast_forward_to(const unsigned char *to, const unsigned char *from)
302{
303 struct ref_lock *ref_lock;
304
305 read_cache();
306 if (checkout_fast_forward(from, to))
307 exit(1); /* the callee should have complained already */
308 ref_lock = lock_any_ref_for_update("HEAD", from, 0);
309 return write_ref_sha1(ref_lock, to, "cherry-pick");
310}
311
ae8c79fd
CC
312static void do_recursive_merge(struct commit *base, struct commit *next,
313 const char *base_label, const char *next_label,
314 unsigned char *head, struct strbuf *msgbuf,
315 char *defmsg)
316{
317 struct merge_options o;
318 struct tree *result, *next_tree, *base_tree, *head_tree;
319 int clean, index_fd;
320 static struct lock_file index_lock;
321
322 index_fd = hold_locked_index(&index_lock, 1);
323
324 read_cache();
325 init_merge_options(&o);
326 o.ancestor = base ? base_label : "(empty tree)";
327 o.branch1 = "HEAD";
328 o.branch2 = next ? next_label : "(empty tree)";
329
330 head_tree = parse_tree_indirect(head);
331 next_tree = next ? next->tree : empty_tree();
332 base_tree = base ? base->tree : empty_tree();
333
334 clean = merge_trees(&o,
335 head_tree,
336 next_tree, base_tree, &result);
337
338 if (active_cache_changed &&
339 (write_cache(index_fd, active_cache, active_nr) ||
340 commit_locked_index(&index_lock)))
341 die("%s: Unable to write new index file", me);
342 rollback_lock_file(&index_lock);
343
344 if (!clean) {
345 int i;
346 strbuf_addstr(msgbuf, "\nConflicts:\n\n");
347 for (i = 0; i < active_nr;) {
348 struct cache_entry *ce = active_cache[i++];
349 if (ce_stage(ce)) {
350 strbuf_addch(msgbuf, '\t');
351 strbuf_addstr(msgbuf, ce->name);
352 strbuf_addch(msgbuf, '\n');
353 while (i < active_nr && !strcmp(ce->name,
354 active_cache[i]->name))
355 i++;
356 }
357 }
358 write_message(msgbuf, defmsg);
359 fprintf(stderr, "Automatic %s failed.%s\n",
360 me, help_msg(commit_name));
361 rerere(allow_rerere_auto);
362 exit(1);
363 }
364 write_message(msgbuf, defmsg);
365 fprintf(stderr, "Finished one %s.\n", me);
366}
367
9509af68
JS
368static int revert_or_cherry_pick(int argc, const char **argv)
369{
370 unsigned char head[20];
7791ecbc 371 struct commit *base, *next, *parent;
bf975d37 372 const char *base_label, *next_label;
d6856540 373 struct commit_message msg = { NULL, NULL, NULL, NULL, NULL };
28db756f 374 char *defmsg = NULL;
bc84a7fb 375 struct strbuf msgbuf = STRBUF_INIT;
9509af68 376
ef90d6d4 377 git_config(git_default_config, NULL);
9509af68
JS
378 me = action == REVERT ? "revert" : "cherry-pick";
379 setenv(GIT_REFLOG_ACTION, me, 0);
f8103794 380 parse_args(argc, argv);
9509af68 381
c62f6ec3
JH
382 if (allow_ff) {
383 if (signoff)
384 die("cherry-pick --ff cannot be used with --signoff");
385 if (no_commit)
386 die("cherry-pick --ff cannot be used with --no-commit");
387 if (no_replay)
388 die("cherry-pick --ff cannot be used with -x");
389 if (edit)
390 die("cherry-pick --ff cannot be used with --edit");
391 }
392
6eb1b437
MV
393 if (read_cache() < 0)
394 die("git %s: failed to read the index", me);
9509af68
JS
395 if (no_commit) {
396 /*
397 * We do not intend to commit immediately. We just want to
71aa2b8f
JH
398 * merge the differences in, so let's compute the tree
399 * that represents the "current" state for merge-recursive
400 * to work on.
9509af68 401 */
45525bd0 402 if (write_cache_as_tree(head, 0, NULL))
9509af68
JS
403 die ("Your index file is unmerged.");
404 } else {
9509af68
JS
405 if (get_sha1("HEAD", head))
406 die ("You do not have a valid HEAD");
75f3ff2e 407 if (index_differs_from("HEAD", 0))
d38a30df 408 die_dirty_index(me);
9509af68 409 }
6eb1b437
MV
410 discard_cache();
411
f95ebf74
JS
412 if (!commit->parents) {
413 if (action == REVERT)
414 die ("Cannot revert a root commit");
415 parent = NULL;
416 }
417 else if (commit->parents->next) {
7791ecbc
JH
418 /* Reverting or cherry-picking a merge commit */
419 int cnt;
420 struct commit_list *p;
421
422 if (!mainline)
423 die("Commit %s is a merge but no -m option was given.",
424 sha1_to_hex(commit->object.sha1));
425
426 for (cnt = 1, p = commit->parents;
427 cnt != mainline && p;
428 cnt++)
429 p = p->next;
430 if (cnt != mainline || !p)
431 die("Commit %s does not have parent %d",
432 sha1_to_hex(commit->object.sha1), mainline);
433 parent = p->item;
434 } else if (0 < mainline)
435 die("Mainline was specified but commit %s is not a merge.",
436 sha1_to_hex(commit->object.sha1));
437 else
438 parent = commit->parents->item;
439
c62f6ec3
JH
440 if (allow_ff && !hashcmp(parent->object.sha1, head))
441 return fast_forward_to(commit->object.sha1, head);
442
6eb1b437
MV
443 if (parent && parse_commit(parent) < 0)
444 die("%s: cannot parse parent commit %s",
445 me, sha1_to_hex(parent->object.sha1));
446
d6856540
JN
447 if (get_message(commit->buffer, &msg) != 0)
448 die("Cannot get commit message for %s",
449 sha1_to_hex(commit->object.sha1));
450
9509af68
JS
451 /*
452 * "commit" is an existing commit. We would want to apply
453 * the difference it introduces since its first parent "prev"
454 * on top of the current HEAD if we are cherry-pick. Or the
455 * reverse of it if we are revert.
456 */
457
28db756f 458 defmsg = git_pathdup("MERGE_MSG");
c62f6ec3 459
9509af68
JS
460 if (action == REVERT) {
461 base = commit;
bf975d37 462 base_label = msg.label;
7791ecbc 463 next = parent;
d6856540 464 next_label = msg.parent_label;
bc84a7fb
CC
465 strbuf_addstr(&msgbuf, "Revert \"");
466 strbuf_addstr(&msgbuf, msg.subject);
467 strbuf_addstr(&msgbuf, "\"\n\nThis reverts commit ");
468 strbuf_addstr(&msgbuf, sha1_to_hex(commit->object.sha1));
d5be89d8
RR
469
470 if (commit->parents->next) {
bc84a7fb
CC
471 strbuf_addstr(&msgbuf, ", reversing\nchanges made to ");
472 strbuf_addstr(&msgbuf, sha1_to_hex(parent->object.sha1));
d5be89d8 473 }
bc84a7fb 474 strbuf_addstr(&msgbuf, ".\n");
9509af68 475 } else {
7791ecbc 476 base = parent;
bf975d37 477 base_label = msg.parent_label;
9509af68 478 next = commit;
d6856540
JN
479 next_label = msg.label;
480 set_author_ident_env(msg.message);
bc84a7fb 481 add_message_to_msg(&msgbuf, msg.message);
f8103794 482 if (no_replay) {
bc84a7fb
CC
483 strbuf_addstr(&msgbuf, "(cherry picked from commit ");
484 strbuf_addstr(&msgbuf, sha1_to_hex(commit->object.sha1));
485 strbuf_addstr(&msgbuf, ")\n");
9509af68
JS
486 }
487 }
9509af68 488
91e52598
CC
489 if (!strategy || !strcmp(strategy, "recursive") || action == REVERT)
490 do_recursive_merge(base, next, base_label, next_label,
491 head, &msgbuf, defmsg);
492 else {
493 int res;
494 struct commit_list *common = NULL;
495 struct commit_list *remotes = NULL;
496 write_message(&msgbuf, defmsg);
497 commit_list_insert(base, &common);
498 commit_list_insert(next, &remotes);
499 res = try_merge_command(strategy, common,
500 sha1_to_hex(head), remotes);
501 free_commit_list(common);
502 free_commit_list(remotes);
503 if (res) {
504 fprintf(stderr, "Automatic %s with strategy %s failed.%s\n",
505 me, strategy, help_msg(commit_name));
506 rerere(allow_rerere_auto);
507 exit(1);
9509af68 508 }
9509af68 509 }
9509af68 510
2fb0e14f
CC
511 free_message(&msg);
512
9509af68
JS
513 /*
514 *
515 * If we are cherry-pick, and if the merge did not result in
516 * hand-editing, we will hit this commit and inherit the original
517 * author date and name.
518 * If we are revert, or if our cherry-pick results in a hand merge,
519 * we had better say that the current user is responsible for that.
520 */
521
522 if (!no_commit) {
cfd9c277
DM
523 /* 6 is max possible length of our args array including NULL */
524 const char *args[6];
2fb0e14f 525 int res;
cfd9c277 526 int i = 0;
2fb0e14f 527
cfd9c277
DM
528 args[i++] = "commit";
529 args[i++] = "-n";
530 if (signoff)
531 args[i++] = "-s";
532 if (!edit) {
533 args[i++] = "-F";
534 args[i++] = defmsg;
535 }
536 args[i] = NULL;
2fb0e14f
CC
537 res = run_command_v_opt(args, RUN_GIT_CMD);
538 free(defmsg);
539
540 return res;
9509af68 541 }
2fb0e14f 542
d258b258 543 free(defmsg);
9509af68
JS
544
545 return 0;
546}
547
548int cmd_revert(int argc, const char **argv, const char *prefix)
549{
550 if (isatty(0))
551 edit = 1;
552 action = REVERT;
553 return revert_or_cherry_pick(argc, argv);
554}
555
556int cmd_cherry_pick(int argc, const char **argv, const char *prefix)
557{
9509af68
JS
558 action = CHERRY_PICK;
559 return revert_or_cherry_pick(argc, argv);
560}