Make builtin-describe.c use parse_options
[git/git.git] / builtin-revert.c
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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"
10
11/*
12 * This implements the builtins revert and cherry-pick.
13 *
14 * Copyright (c) 2007 Johannes E. Schindelin
15 *
16 * Based on git-revert.sh, which is
17 *
18 * Copyright (c) 2005 Linus Torvalds
19 * Copyright (c) 2005 Junio C Hamano
20 */
21
22static const char *revert_usage = "git-revert [--edit | --no-edit] [-n] <commit-ish>";
23
24static const char *cherry_pick_usage = "git-cherry-pick [--edit] [-n] [-r] [-x] <commit-ish>";
25
26static int edit;
27static int replay;
4175e9e3 28static enum { REVERT, CHERRY_PICK } action;
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29static int no_commit;
30static struct commit *commit;
31static int needed_deref;
32
33static const char *me;
34
35#define GIT_REFLOG_ACTION "GIT_REFLOG_ACTION"
36
37static void parse_options(int argc, const char **argv)
38{
39 const char *usage_str = action == REVERT ?
40 revert_usage : cherry_pick_usage;
41 unsigned char sha1[20];
42 const char *arg;
43 int i;
44
45 if (argc < 2)
46 usage(usage_str);
47
32309f54 48 for (i = 1; i < argc; i++) {
9509af68 49 arg = argv[i];
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50 if (arg[0] != '-')
51 break;
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52 if (!strcmp(arg, "-n") || !strcmp(arg, "--no-commit"))
53 no_commit = 1;
54 else if (!strcmp(arg, "-e") || !strcmp(arg, "--edit"))
55 edit = 1;
56 else if (!strcmp(arg, "--no-edit"))
57 edit = 0;
58 else if (!strcmp(arg, "-x") || !strcmp(arg, "--i-really-want-"
59 "to-expose-my-private-commit-object-name"))
60 replay = 0;
61 else if (strcmp(arg, "-r"))
62 usage(usage_str);
63 }
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64 if (i != argc - 1)
65 usage(usage_str);
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66 arg = argv[argc - 1];
67 if (get_sha1(arg, sha1))
68 die ("Cannot find '%s'", arg);
69 commit = (struct commit *)parse_object(sha1);
70 if (!commit)
71 die ("Could not find %s", sha1_to_hex(sha1));
72 if (commit->object.type == OBJ_TAG) {
73 commit = (struct commit *)
74 deref_tag((struct object *)commit, arg, strlen(arg));
75 needed_deref = 1;
76 }
77 if (commit->object.type != OBJ_COMMIT)
78 die ("'%s' does not point to a commit", arg);
79}
80
81static char *get_oneline(const char *message)
82{
83 char *result;
84 const char *p = message, *abbrev, *eol;
85 int abbrev_len, oneline_len;
86
87 if (!p)
88 die ("Could not read commit message of %s",
89 sha1_to_hex(commit->object.sha1));
90 while (*p && (*p != '\n' || p[1] != '\n'))
91 p++;
92
93 if (*p) {
94 p += 2;
95 for (eol = p + 1; *eol && *eol != '\n'; eol++)
96 ; /* do nothing */
97 } else
98 eol = p;
99 abbrev = find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV);
100 abbrev_len = strlen(abbrev);
101 oneline_len = eol - p;
102 result = xmalloc(abbrev_len + 5 + oneline_len);
103 memcpy(result, abbrev, abbrev_len);
104 memcpy(result + abbrev_len, "... ", 4);
105 memcpy(result + abbrev_len + 4, p, oneline_len);
106 result[abbrev_len + 4 + oneline_len] = '\0';
107 return result;
108}
109
52fae7de 110static char *get_encoding(const char *message)
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111{
112 const char *p = message, *eol;
113
114 if (!p)
115 die ("Could not read commit message of %s",
116 sha1_to_hex(commit->object.sha1));
117 while (*p && *p != '\n') {
118 for (eol = p + 1; *eol && *eol != '\n'; eol++)
119 ; /* do nothing */
120 if (!prefixcmp(p, "encoding ")) {
121 char *result = xmalloc(eol - 8 - p);
122 strlcpy(result, p + 9, eol - 8 - p);
123 return result;
124 }
125 p = eol;
126 if (*p == '\n')
127 p++;
128 }
129 return NULL;
130}
131
4175e9e3 132static struct lock_file msg_file;
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133static int msg_fd;
134
135static void add_to_msg(const char *string)
136{
137 int len = strlen(string);
138 if (write_in_full(msg_fd, string, len) < 0)
1dcb3b64 139 die ("Could not write to MERGE_MSG");
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140}
141
142static void add_message_to_msg(const char *message)
143{
144 const char *p = message;
145 while (*p && (*p != '\n' || p[1] != '\n'))
146 p++;
147
148 if (!*p)
149 add_to_msg(sha1_to_hex(commit->object.sha1));
150
151 p += 2;
152 add_to_msg(p);
153 return;
154}
155
156static void set_author_ident_env(const char *message)
157{
158 const char *p = message;
159 if (!p)
160 die ("Could not read commit message of %s",
161 sha1_to_hex(commit->object.sha1));
162 while (*p && *p != '\n') {
163 const char *eol;
164
165 for (eol = p; *eol && *eol != '\n'; eol++)
166 ; /* do nothing */
167 if (!prefixcmp(p, "author ")) {
168 char *line, *pend, *email, *timestamp;
169
170 p += 7;
182af834 171 line = xmemdupz(p, eol - p);
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172 email = strchr(line, '<');
173 if (!email)
174 die ("Could not extract author email from %s",
175 sha1_to_hex(commit->object.sha1));
176 if (email == line)
177 pend = line;
178 else
179 for (pend = email; pend != line + 1 &&
180 isspace(pend[-1]); pend--);
181 ; /* do nothing */
182 *pend = '\0';
183 email++;
184 timestamp = strchr(email, '>');
185 if (!timestamp)
186 die ("Could not extract author email from %s",
187 sha1_to_hex(commit->object.sha1));
188 *timestamp = '\0';
189 for (timestamp++; *timestamp && isspace(*timestamp);
190 timestamp++)
191 ; /* do nothing */
192 setenv("GIT_AUTHOR_NAME", line, 1);
193 setenv("GIT_AUTHOR_EMAIL", email, 1);
194 setenv("GIT_AUTHOR_DATE", timestamp, 1);
195 free(line);
196 return;
197 }
198 p = eol;
199 if (*p == '\n')
200 p++;
201 }
202 die ("No author information found in %s",
203 sha1_to_hex(commit->object.sha1));
204}
205
206static int merge_recursive(const char *base_sha1,
207 const char *head_sha1, const char *head_name,
208 const char *next_sha1, const char *next_name)
209{
210 char buffer[256];
497bdc88 211 const char *argv[6];
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212
213 sprintf(buffer, "GITHEAD_%s", head_sha1);
214 setenv(buffer, head_name, 1);
215 sprintf(buffer, "GITHEAD_%s", next_sha1);
216 setenv(buffer, next_name, 1);
217
218 /*
219 * This three way merge is an interesting one. We are at
220 * $head, and would want to apply the change between $commit
221 * and $prev on top of us (when reverting), or the change between
222 * $prev and $commit on top of us (when cherry-picking or replaying).
223 */
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224 argv[0] = "merge-recursive";
225 argv[1] = base_sha1;
226 argv[2] = "--";
227 argv[3] = head_sha1;
228 argv[4] = next_sha1;
229 argv[5] = NULL;
230
231 return run_command_v_opt(argv, RUN_COMMAND_NO_STDIN | RUN_GIT_CMD);
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232}
233
234static int revert_or_cherry_pick(int argc, const char **argv)
235{
236 unsigned char head[20];
237 struct commit *base, *next;
238 int i;
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239 char *oneline, *reencoded_message = NULL;
240 const char *message, *encoding;
abda5227 241 const char *defmsg = xstrdup(git_path("MERGE_MSG"));
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242
243 git_config(git_default_config);
244 me = action == REVERT ? "revert" : "cherry-pick";
245 setenv(GIT_REFLOG_ACTION, me, 0);
246 parse_options(argc, argv);
247
248 /* this is copied from the shell script, but it's never triggered... */
249 if (action == REVERT && replay)
250 die("revert is incompatible with replay");
251
252 if (no_commit) {
253 /*
254 * We do not intend to commit immediately. We just want to
255 * merge the differences in.
256 */
257 if (write_tree(head, 0, NULL))
258 die ("Your index file is unmerged.");
259 } else {
260 struct wt_status s;
261
262 if (get_sha1("HEAD", head))
263 die ("You do not have a valid HEAD");
264 wt_status_prepare(&s);
265 if (s.commitable || s.workdir_dirty)
266 die ("Dirty index: cannot %s", me);
267 discard_cache();
268 }
269
270 if (!commit->parents)
271 die ("Cannot %s a root commit", me);
272 if (commit->parents->next)
273 die ("Cannot %s a multi-parent commit.", me);
274 if (!(message = commit->buffer))
275 die ("Cannot get commit message for %s",
276 sha1_to_hex(commit->object.sha1));
277
278 /*
279 * "commit" is an existing commit. We would want to apply
280 * the difference it introduces since its first parent "prev"
281 * on top of the current HEAD if we are cherry-pick. Or the
282 * reverse of it if we are revert.
283 */
284
abda5227 285 msg_fd = hold_lock_file_for_update(&msg_file, defmsg, 1);
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286
287 encoding = get_encoding(message);
288 if (!encoding)
289 encoding = "utf-8";
290 if (!git_commit_encoding)
291 git_commit_encoding = "utf-8";
292 if ((reencoded_message = reencode_string(message,
293 git_commit_encoding, encoding)))
294 message = reencoded_message;
295
296 oneline = get_oneline(message);
297
298 if (action == REVERT) {
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299 char *oneline_body = strchr(oneline, ' ');
300
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301 base = commit;
302 next = commit->parents->item;
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303 add_to_msg("Revert \"");
304 add_to_msg(oneline_body + 1);
305 add_to_msg("\"\n\nThis reverts commit ");
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306 add_to_msg(sha1_to_hex(commit->object.sha1));
307 add_to_msg(".\n");
308 } else {
309 base = commit->parents->item;
310 next = commit;
311 set_author_ident_env(message);
312 add_message_to_msg(message);
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313 if (!replay) {
314 add_to_msg("(cherry picked from commit ");
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315 add_to_msg(sha1_to_hex(commit->object.sha1));
316 add_to_msg(")\n");
317 }
318 }
319 if (needed_deref) {
320 add_to_msg("(original 'git ");
321 add_to_msg(me);
322 add_to_msg("' arguments: ");
323 for (i = 0; i < argc; i++) {
324 if (i)
325 add_to_msg(" ");
326 add_to_msg(argv[i]);
327 }
328 add_to_msg(")\n");
329 }
330
331 if (merge_recursive(sha1_to_hex(base->object.sha1),
332 sha1_to_hex(head), "HEAD",
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333 sha1_to_hex(next->object.sha1), oneline) ||
334 write_tree(head, 0, NULL)) {
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335 add_to_msg("\nConflicts:\n\n");
336 read_cache();
337 for (i = 0; i < active_nr;) {
338 struct cache_entry *ce = active_cache[i++];
339 if (ce_stage(ce)) {
340 add_to_msg("\t");
341 add_to_msg(ce->name);
342 add_to_msg("\n");
343 while (i < active_nr && !strcmp(ce->name,
344 active_cache[i]->name))
345 i++;
346 }
347 }
348 if (close(msg_fd) || commit_lock_file(&msg_file) < 0)
abda5227 349 die ("Error wrapping up %s", defmsg);
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350 fprintf(stderr, "Automatic %s failed. "
351 "After resolving the conflicts,\n"
352 "mark the corrected paths with 'git-add <paths>'\n"
353 "and commit the result.\n", me);
354 if (action == CHERRY_PICK) {
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355 fprintf(stderr, "When commiting, use the option "
356 "'-c %s' to retain authorship and message.\n",
357 find_unique_abbrev(commit->object.sha1,
358 DEFAULT_ABBREV));
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359 }
360 exit(1);
361 }
362 if (close(msg_fd) || commit_lock_file(&msg_file) < 0)
abda5227 363 die ("Error wrapping up %s", defmsg);
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364 fprintf(stderr, "Finished one %s.\n", me);
365
366 /*
367 *
368 * If we are cherry-pick, and if the merge did not result in
369 * hand-editing, we will hit this commit and inherit the original
370 * author date and name.
371 * If we are revert, or if our cherry-pick results in a hand merge,
372 * we had better say that the current user is responsible for that.
373 */
374
375 if (!no_commit) {
376 if (edit)
abda5227 377 return execl_git_cmd("commit", "-n", NULL);
9509af68 378 else
abda5227 379 return execl_git_cmd("commit", "-n", "-F", defmsg, NULL);
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380 }
381 if (reencoded_message)
382 free(reencoded_message);
383
384 return 0;
385}
386
387int cmd_revert(int argc, const char **argv, const char *prefix)
388{
389 if (isatty(0))
390 edit = 1;
391 action = REVERT;
392 return revert_or_cherry_pick(argc, argv);
393}
394
395int cmd_cherry_pick(int argc, const char **argv, const char *prefix)
396{
397 replay = 1;
398 action = CHERRY_PICK;
399 return revert_or_cherry_pick(argc, argv);
400}