gitweb: use new Git::Repo API, and add optional caching
[git/gitweb-caching.git] / builtin-revert.c
blob36677053f87b107f658f1472369755c4fe957a46
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"
10 #include "parse-options.h"
11 #include "cache-tree.h"
12 #include "diff.h"
13 #include "revision.h"
14 #include "rerere.h"
17 * This implements the builtins revert and cherry-pick.
19 * Copyright (c) 2007 Johannes E. Schindelin
21 * Based on git-revert.sh, which is
23 * Copyright (c) 2005 Linus Torvalds
24 * Copyright (c) 2005 Junio C Hamano
27 static const char * const revert_usage[] = {
28 "git revert [options] <commit-ish>",
29 NULL
32 static const char * const cherry_pick_usage[] = {
33 "git cherry-pick [options] <commit-ish>",
34 NULL
37 static int edit, no_replay, no_commit, mainline, signoff;
38 static enum { REVERT, CHERRY_PICK } action;
39 static struct commit *commit;
41 static const char *me;
43 #define GIT_REFLOG_ACTION "GIT_REFLOG_ACTION"
45 static void parse_args(int argc, const char **argv)
47 const char * const * usage_str =
48 action == REVERT ? revert_usage : cherry_pick_usage;
49 unsigned char sha1[20];
50 const char *arg;
51 int noop;
52 struct option options[] = {
53 OPT_BOOLEAN('n', "no-commit", &no_commit, "don't automatically commit"),
54 OPT_BOOLEAN('e', "edit", &edit, "edit the commit message"),
55 OPT_BOOLEAN('x', NULL, &no_replay, "append commit name when cherry-picking"),
56 OPT_BOOLEAN('r', NULL, &noop, "no-op (backward compatibility)"),
57 OPT_BOOLEAN('s', "signoff", &signoff, "add Signed-off-by:"),
58 OPT_INTEGER('m', "mainline", &mainline, "parent number"),
59 OPT_END(),
62 if (parse_options(argc, argv, options, usage_str, 0) != 1)
63 usage_with_options(usage_str, options);
64 arg = argv[0];
66 if (get_sha1(arg, sha1))
67 die ("Cannot find '%s'", arg);
68 commit = (struct commit *)parse_object(sha1);
69 if (!commit)
70 die ("Could not find %s", sha1_to_hex(sha1));
71 if (commit->object.type == OBJ_TAG) {
72 commit = (struct commit *)
73 deref_tag((struct object *)commit, arg, strlen(arg));
75 if (commit->object.type != OBJ_COMMIT)
76 die ("'%s' does not point to a commit", arg);
79 static char *get_oneline(const char *message)
81 char *result;
82 const char *p = message, *abbrev, *eol;
83 int abbrev_len, oneline_len;
85 if (!p)
86 die ("Could not read commit message of %s",
87 sha1_to_hex(commit->object.sha1));
88 while (*p && (*p != '\n' || p[1] != '\n'))
89 p++;
91 if (*p) {
92 p += 2;
93 for (eol = p + 1; *eol && *eol != '\n'; eol++)
94 ; /* do nothing */
95 } else
96 eol = p;
97 abbrev = find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV);
98 abbrev_len = strlen(abbrev);
99 oneline_len = eol - p;
100 result = xmalloc(abbrev_len + 5 + oneline_len);
101 memcpy(result, abbrev, abbrev_len);
102 memcpy(result + abbrev_len, "... ", 4);
103 memcpy(result + abbrev_len + 4, p, oneline_len);
104 result[abbrev_len + 4 + oneline_len] = '\0';
105 return result;
108 static char *get_encoding(const char *message)
110 const char *p = message, *eol;
112 if (!p)
113 die ("Could not read commit message of %s",
114 sha1_to_hex(commit->object.sha1));
115 while (*p && *p != '\n') {
116 for (eol = p + 1; *eol && *eol != '\n'; eol++)
117 ; /* do nothing */
118 if (!prefixcmp(p, "encoding ")) {
119 char *result = xmalloc(eol - 8 - p);
120 strlcpy(result, p + 9, eol - 8 - p);
121 return result;
123 p = eol;
124 if (*p == '\n')
125 p++;
127 return NULL;
130 static struct lock_file msg_file;
131 static int msg_fd;
133 static void add_to_msg(const char *string)
135 int len = strlen(string);
136 if (write_in_full(msg_fd, string, len) < 0)
137 die ("Could not write to MERGE_MSG");
140 static void add_message_to_msg(const char *message)
142 const char *p = message;
143 while (*p && (*p != '\n' || p[1] != '\n'))
144 p++;
146 if (!*p)
147 add_to_msg(sha1_to_hex(commit->object.sha1));
149 p += 2;
150 add_to_msg(p);
151 return;
154 static void set_author_ident_env(const char *message)
156 const char *p = message;
157 if (!p)
158 die ("Could not read commit message of %s",
159 sha1_to_hex(commit->object.sha1));
160 while (*p && *p != '\n') {
161 const char *eol;
163 for (eol = p; *eol && *eol != '\n'; eol++)
164 ; /* do nothing */
165 if (!prefixcmp(p, "author ")) {
166 char *line, *pend, *email, *timestamp;
168 p += 7;
169 line = xmemdupz(p, eol - p);
170 email = strchr(line, '<');
171 if (!email)
172 die ("Could not extract author email from %s",
173 sha1_to_hex(commit->object.sha1));
174 if (email == line)
175 pend = line;
176 else
177 for (pend = email; pend != line + 1 &&
178 isspace(pend[-1]); pend--);
179 ; /* do nothing */
180 *pend = '\0';
181 email++;
182 timestamp = strchr(email, '>');
183 if (!timestamp)
184 die ("Could not extract author time from %s",
185 sha1_to_hex(commit->object.sha1));
186 *timestamp = '\0';
187 for (timestamp++; *timestamp && isspace(*timestamp);
188 timestamp++)
189 ; /* do nothing */
190 setenv("GIT_AUTHOR_NAME", line, 1);
191 setenv("GIT_AUTHOR_EMAIL", email, 1);
192 setenv("GIT_AUTHOR_DATE", timestamp, 1);
193 free(line);
194 return;
196 p = eol;
197 if (*p == '\n')
198 p++;
200 die ("No author information found in %s",
201 sha1_to_hex(commit->object.sha1));
204 static int merge_recursive(const char *base_sha1,
205 const char *head_sha1, const char *head_name,
206 const char *next_sha1, const char *next_name)
208 char buffer[256];
209 const char *argv[6];
210 int i = 0;
212 sprintf(buffer, "GITHEAD_%s", head_sha1);
213 setenv(buffer, head_name, 1);
214 sprintf(buffer, "GITHEAD_%s", next_sha1);
215 setenv(buffer, next_name, 1);
218 * This three way merge is an interesting one. We are at
219 * $head, and would want to apply the change between $commit
220 * and $prev on top of us (when reverting), or the change between
221 * $prev and $commit on top of us (when cherry-picking or replaying).
223 argv[i++] = "merge-recursive";
224 if (base_sha1)
225 argv[i++] = base_sha1;
226 argv[i++] = "--";
227 argv[i++] = head_sha1;
228 argv[i++] = next_sha1;
229 argv[i++] = NULL;
231 return run_command_v_opt(argv, RUN_COMMAND_NO_STDIN | RUN_GIT_CMD);
234 static char *help_msg(const unsigned char *sha1)
236 static char helpbuf[1024];
237 char *msg = getenv("GIT_CHERRY_PICK_HELP");
239 if (msg)
240 return msg;
242 strcpy(helpbuf, " After resolving the conflicts,\n"
243 "mark the corrected paths with 'git add <paths>' "
244 "or 'git rm <paths>' and commit the result.");
246 if (action == CHERRY_PICK) {
247 sprintf(helpbuf + strlen(helpbuf),
248 "\nWhen commiting, use the option "
249 "'-c %s' to retain authorship and message.",
250 find_unique_abbrev(sha1, DEFAULT_ABBREV));
252 return helpbuf;
255 static int index_is_dirty(void)
257 struct rev_info rev;
258 init_revisions(&rev, NULL);
259 setup_revisions(0, NULL, &rev, "HEAD");
260 DIFF_OPT_SET(&rev.diffopt, QUIET);
261 DIFF_OPT_SET(&rev.diffopt, EXIT_WITH_STATUS);
262 run_diff_index(&rev, 1);
263 return !!DIFF_OPT_TST(&rev.diffopt, HAS_CHANGES);
266 static int revert_or_cherry_pick(int argc, const char **argv)
268 unsigned char head[20];
269 struct commit *base, *next, *parent;
270 int i;
271 char *oneline, *reencoded_message = NULL;
272 const char *message, *encoding;
273 const char *defmsg = xstrdup(git_path("MERGE_MSG"));
275 git_config(git_default_config, NULL);
276 me = action == REVERT ? "revert" : "cherry-pick";
277 setenv(GIT_REFLOG_ACTION, me, 0);
278 parse_args(argc, argv);
280 /* this is copied from the shell script, but it's never triggered... */
281 if (action == REVERT && !no_replay)
282 die("revert is incompatible with replay");
284 if (no_commit) {
286 * We do not intend to commit immediately. We just want to
287 * merge the differences in, so let's compute the tree
288 * that represents the "current" state for merge-recursive
289 * to work on.
291 if (write_cache_as_tree(head, 0, NULL))
292 die ("Your index file is unmerged.");
293 } else {
294 if (get_sha1("HEAD", head))
295 die ("You do not have a valid HEAD");
296 if (read_cache() < 0)
297 die("could not read the index");
298 if (index_is_dirty())
299 die ("Dirty index: cannot %s", me);
300 discard_cache();
303 if (!commit->parents) {
304 if (action == REVERT)
305 die ("Cannot revert a root commit");
306 parent = NULL;
308 else if (commit->parents->next) {
309 /* Reverting or cherry-picking a merge commit */
310 int cnt;
311 struct commit_list *p;
313 if (!mainline)
314 die("Commit %s is a merge but no -m option was given.",
315 sha1_to_hex(commit->object.sha1));
317 for (cnt = 1, p = commit->parents;
318 cnt != mainline && p;
319 cnt++)
320 p = p->next;
321 if (cnt != mainline || !p)
322 die("Commit %s does not have parent %d",
323 sha1_to_hex(commit->object.sha1), mainline);
324 parent = p->item;
325 } else if (0 < mainline)
326 die("Mainline was specified but commit %s is not a merge.",
327 sha1_to_hex(commit->object.sha1));
328 else
329 parent = commit->parents->item;
331 if (!(message = commit->buffer))
332 die ("Cannot get commit message for %s",
333 sha1_to_hex(commit->object.sha1));
336 * "commit" is an existing commit. We would want to apply
337 * the difference it introduces since its first parent "prev"
338 * on top of the current HEAD if we are cherry-pick. Or the
339 * reverse of it if we are revert.
342 msg_fd = hold_lock_file_for_update(&msg_file, defmsg, 1);
344 encoding = get_encoding(message);
345 if (!encoding)
346 encoding = "utf-8";
347 if (!git_commit_encoding)
348 git_commit_encoding = "utf-8";
349 if ((reencoded_message = reencode_string(message,
350 git_commit_encoding, encoding)))
351 message = reencoded_message;
353 oneline = get_oneline(message);
355 if (action == REVERT) {
356 char *oneline_body = strchr(oneline, ' ');
358 base = commit;
359 next = parent;
360 add_to_msg("Revert \"");
361 add_to_msg(oneline_body + 1);
362 add_to_msg("\"\n\nThis reverts commit ");
363 add_to_msg(sha1_to_hex(commit->object.sha1));
364 add_to_msg(".\n");
365 } else {
366 base = parent;
367 next = commit;
368 set_author_ident_env(message);
369 add_message_to_msg(message);
370 if (no_replay) {
371 add_to_msg("(cherry picked from commit ");
372 add_to_msg(sha1_to_hex(commit->object.sha1));
373 add_to_msg(")\n");
377 if (merge_recursive(base == NULL ?
378 NULL : sha1_to_hex(base->object.sha1),
379 sha1_to_hex(head), "HEAD",
380 sha1_to_hex(next->object.sha1), oneline) ||
381 write_cache_as_tree(head, 0, NULL)) {
382 add_to_msg("\nConflicts:\n\n");
383 read_cache();
384 for (i = 0; i < active_nr;) {
385 struct cache_entry *ce = active_cache[i++];
386 if (ce_stage(ce)) {
387 add_to_msg("\t");
388 add_to_msg(ce->name);
389 add_to_msg("\n");
390 while (i < active_nr && !strcmp(ce->name,
391 active_cache[i]->name))
392 i++;
395 if (commit_lock_file(&msg_file) < 0)
396 die ("Error wrapping up %s", defmsg);
397 fprintf(stderr, "Automatic %s failed.%s\n",
398 me, help_msg(commit->object.sha1));
399 rerere();
400 exit(1);
402 if (commit_lock_file(&msg_file) < 0)
403 die ("Error wrapping up %s", defmsg);
404 fprintf(stderr, "Finished one %s.\n", me);
408 * If we are cherry-pick, and if the merge did not result in
409 * hand-editing, we will hit this commit and inherit the original
410 * author date and name.
411 * If we are revert, or if our cherry-pick results in a hand merge,
412 * we had better say that the current user is responsible for that.
415 if (!no_commit) {
416 /* 6 is max possible length of our args array including NULL */
417 const char *args[6];
418 int i = 0;
419 args[i++] = "commit";
420 args[i++] = "-n";
421 if (signoff)
422 args[i++] = "-s";
423 if (!edit) {
424 args[i++] = "-F";
425 args[i++] = defmsg;
427 args[i] = NULL;
428 return execv_git_cmd(args);
430 free(reencoded_message);
432 return 0;
435 int cmd_revert(int argc, const char **argv, const char *prefix)
437 if (isatty(0))
438 edit = 1;
439 no_replay = 1;
440 action = REVERT;
441 return revert_or_cherry_pick(argc, argv);
444 int cmd_cherry_pick(int argc, const char **argv, const char *prefix)
446 no_replay = 0;
447 action = CHERRY_PICK;
448 return revert_or_cherry_pick(argc, argv);