cache.h: add repository argument to oid_object_info
[git/git.git] / builtin / replace.c
1 /*
2 * Builtin "git replace"
3 *
4 * Copyright (c) 2008 Christian Couder <chriscool@tuxfamily.org>
5 *
6 * Based on builtin/tag.c by Kristian Høgsberg <krh@redhat.com>
7 * and Carlos Rica <jasampler@gmail.com> that was itself based on
8 * git-tag.sh and mktag.c by Linus Torvalds.
9 */
10
11 #include "cache.h"
12 #include "config.h"
13 #include "builtin.h"
14 #include "refs.h"
15 #include "parse-options.h"
16 #include "run-command.h"
17 #include "object-store.h"
18 #include "repository.h"
19 #include "tag.h"
20
21 static const char * const git_replace_usage[] = {
22 N_("git replace [-f] <object> <replacement>"),
23 N_("git replace [-f] --edit <object>"),
24 N_("git replace [-f] --graft <commit> [<parent>...]"),
25 N_("git replace -d <object>..."),
26 N_("git replace [--format=<format>] [-l [<pattern>]]"),
27 NULL
28 };
29
30 enum replace_format {
31 REPLACE_FORMAT_SHORT,
32 REPLACE_FORMAT_MEDIUM,
33 REPLACE_FORMAT_LONG
34 };
35
36 struct show_data {
37 const char *pattern;
38 enum replace_format format;
39 };
40
41 static int show_reference(const char *refname, const struct object_id *oid,
42 int flag, void *cb_data)
43 {
44 struct show_data *data = cb_data;
45
46 if (!wildmatch(data->pattern, refname, 0)) {
47 if (data->format == REPLACE_FORMAT_SHORT)
48 printf("%s\n", refname);
49 else if (data->format == REPLACE_FORMAT_MEDIUM)
50 printf("%s -> %s\n", refname, oid_to_hex(oid));
51 else { /* data->format == REPLACE_FORMAT_LONG */
52 struct object_id object;
53 enum object_type obj_type, repl_type;
54
55 if (get_oid(refname, &object))
56 return error("Failed to resolve '%s' as a valid ref.", refname);
57
58 obj_type = oid_object_info(the_repository, &object,
59 NULL);
60 repl_type = oid_object_info(the_repository, oid, NULL);
61
62 printf("%s (%s) -> %s (%s)\n", refname, type_name(obj_type),
63 oid_to_hex(oid), type_name(repl_type));
64 }
65 }
66
67 return 0;
68 }
69
70 static int list_replace_refs(const char *pattern, const char *format)
71 {
72 struct show_data data;
73
74 if (pattern == NULL)
75 pattern = "*";
76 data.pattern = pattern;
77
78 if (format == NULL || *format == '\0' || !strcmp(format, "short"))
79 data.format = REPLACE_FORMAT_SHORT;
80 else if (!strcmp(format, "medium"))
81 data.format = REPLACE_FORMAT_MEDIUM;
82 else if (!strcmp(format, "long"))
83 data.format = REPLACE_FORMAT_LONG;
84 else
85 die("invalid replace format '%s'\n"
86 "valid formats are 'short', 'medium' and 'long'\n",
87 format);
88
89 for_each_replace_ref(the_repository, show_reference, (void *)&data);
90
91 return 0;
92 }
93
94 typedef int (*each_replace_name_fn)(const char *name, const char *ref,
95 const struct object_id *oid);
96
97 static int for_each_replace_name(const char **argv, each_replace_name_fn fn)
98 {
99 const char **p, *full_hex;
100 struct strbuf ref = STRBUF_INIT;
101 size_t base_len;
102 int had_error = 0;
103 struct object_id oid;
104
105 strbuf_addstr(&ref, git_replace_ref_base);
106 base_len = ref.len;
107
108 for (p = argv; *p; p++) {
109 if (get_oid(*p, &oid)) {
110 error("Failed to resolve '%s' as a valid ref.", *p);
111 had_error = 1;
112 continue;
113 }
114
115 strbuf_setlen(&ref, base_len);
116 strbuf_addstr(&ref, oid_to_hex(&oid));
117 full_hex = ref.buf + base_len;
118
119 if (read_ref(ref.buf, &oid)) {
120 error("replace ref '%s' not found.", full_hex);
121 had_error = 1;
122 continue;
123 }
124 if (fn(full_hex, ref.buf, &oid))
125 had_error = 1;
126 }
127 strbuf_release(&ref);
128 return had_error;
129 }
130
131 static int delete_replace_ref(const char *name, const char *ref,
132 const struct object_id *oid)
133 {
134 if (delete_ref(NULL, ref, oid, 0))
135 return 1;
136 printf("Deleted replace ref '%s'\n", name);
137 return 0;
138 }
139
140 static void check_ref_valid(struct object_id *object,
141 struct object_id *prev,
142 struct strbuf *ref,
143 int force)
144 {
145 strbuf_reset(ref);
146 strbuf_addf(ref, "%s%s", git_replace_ref_base, oid_to_hex(object));
147 if (check_refname_format(ref->buf, 0))
148 die("'%s' is not a valid ref name.", ref->buf);
149
150 if (read_ref(ref->buf, prev))
151 oidclr(prev);
152 else if (!force)
153 die("replace ref '%s' already exists", ref->buf);
154 }
155
156 static int replace_object_oid(const char *object_ref,
157 struct object_id *object,
158 const char *replace_ref,
159 struct object_id *repl,
160 int force)
161 {
162 struct object_id prev;
163 enum object_type obj_type, repl_type;
164 struct strbuf ref = STRBUF_INIT;
165 struct ref_transaction *transaction;
166 struct strbuf err = STRBUF_INIT;
167
168 obj_type = oid_object_info(the_repository, object, NULL);
169 repl_type = oid_object_info(the_repository, repl, NULL);
170 if (!force && obj_type != repl_type)
171 die("Objects must be of the same type.\n"
172 "'%s' points to a replaced object of type '%s'\n"
173 "while '%s' points to a replacement object of type '%s'.",
174 object_ref, type_name(obj_type),
175 replace_ref, type_name(repl_type));
176
177 check_ref_valid(object, &prev, &ref, force);
178
179 transaction = ref_transaction_begin(&err);
180 if (!transaction ||
181 ref_transaction_update(transaction, ref.buf, repl, &prev,
182 0, NULL, &err) ||
183 ref_transaction_commit(transaction, &err))
184 die("%s", err.buf);
185
186 ref_transaction_free(transaction);
187 strbuf_release(&ref);
188 return 0;
189 }
190
191 static int replace_object(const char *object_ref, const char *replace_ref, int force)
192 {
193 struct object_id object, repl;
194
195 if (get_oid(object_ref, &object))
196 die("Failed to resolve '%s' as a valid ref.", object_ref);
197 if (get_oid(replace_ref, &repl))
198 die("Failed to resolve '%s' as a valid ref.", replace_ref);
199
200 return replace_object_oid(object_ref, &object, replace_ref, &repl, force);
201 }
202
203 /*
204 * Write the contents of the object named by "sha1" to the file "filename".
205 * If "raw" is true, then the object's raw contents are printed according to
206 * "type". Otherwise, we pretty-print the contents for human editing.
207 */
208 static void export_object(const struct object_id *oid, enum object_type type,
209 int raw, const char *filename)
210 {
211 struct child_process cmd = CHILD_PROCESS_INIT;
212 int fd;
213
214 fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
215 if (fd < 0)
216 die_errno("unable to open %s for writing", filename);
217
218 argv_array_push(&cmd.args, "--no-replace-objects");
219 argv_array_push(&cmd.args, "cat-file");
220 if (raw)
221 argv_array_push(&cmd.args, type_name(type));
222 else
223 argv_array_push(&cmd.args, "-p");
224 argv_array_push(&cmd.args, oid_to_hex(oid));
225 cmd.git_cmd = 1;
226 cmd.out = fd;
227
228 if (run_command(&cmd))
229 die("cat-file reported failure");
230 }
231
232 /*
233 * Read a previously-exported (and possibly edited) object back from "filename",
234 * interpreting it as "type", and writing the result to the object database.
235 * The sha1 of the written object is returned via sha1.
236 */
237 static void import_object(struct object_id *oid, enum object_type type,
238 int raw, const char *filename)
239 {
240 int fd;
241
242 fd = open(filename, O_RDONLY);
243 if (fd < 0)
244 die_errno("unable to open %s for reading", filename);
245
246 if (!raw && type == OBJ_TREE) {
247 const char *argv[] = { "mktree", NULL };
248 struct child_process cmd = CHILD_PROCESS_INIT;
249 struct strbuf result = STRBUF_INIT;
250
251 cmd.argv = argv;
252 cmd.git_cmd = 1;
253 cmd.in = fd;
254 cmd.out = -1;
255
256 if (start_command(&cmd))
257 die("unable to spawn mktree");
258
259 if (strbuf_read(&result, cmd.out, 41) < 0)
260 die_errno("unable to read from mktree");
261 close(cmd.out);
262
263 if (finish_command(&cmd))
264 die("mktree reported failure");
265 if (get_oid_hex(result.buf, oid) < 0)
266 die("mktree did not return an object name");
267
268 strbuf_release(&result);
269 } else {
270 struct stat st;
271 int flags = HASH_FORMAT_CHECK | HASH_WRITE_OBJECT;
272
273 if (fstat(fd, &st) < 0)
274 die_errno("unable to fstat %s", filename);
275 if (index_fd(oid, fd, &st, type, NULL, flags) < 0)
276 die("unable to write object to database");
277 /* index_fd close()s fd for us */
278 }
279
280 /*
281 * No need to close(fd) here; both run-command and index-fd
282 * will have done it for us.
283 */
284 }
285
286 static int edit_and_replace(const char *object_ref, int force, int raw)
287 {
288 char *tmpfile = git_pathdup("REPLACE_EDITOBJ");
289 enum object_type type;
290 struct object_id old_oid, new_oid, prev;
291 struct strbuf ref = STRBUF_INIT;
292
293 if (get_oid(object_ref, &old_oid) < 0)
294 die("Not a valid object name: '%s'", object_ref);
295
296 type = oid_object_info(the_repository, &old_oid, NULL);
297 if (type < 0)
298 die("unable to get object type for %s", oid_to_hex(&old_oid));
299
300 check_ref_valid(&old_oid, &prev, &ref, force);
301 strbuf_release(&ref);
302
303 export_object(&old_oid, type, raw, tmpfile);
304 if (launch_editor(tmpfile, NULL, NULL) < 0)
305 die("editing object file failed");
306 import_object(&new_oid, type, raw, tmpfile);
307
308 free(tmpfile);
309
310 if (!oidcmp(&old_oid, &new_oid))
311 return error("new object is the same as the old one: '%s'", oid_to_hex(&old_oid));
312
313 return replace_object_oid(object_ref, &old_oid, "replacement", &new_oid, force);
314 }
315
316 static void replace_parents(struct strbuf *buf, int argc, const char **argv)
317 {
318 struct strbuf new_parents = STRBUF_INIT;
319 const char *parent_start, *parent_end;
320 int i;
321
322 /* find existing parents */
323 parent_start = buf->buf;
324 parent_start += GIT_SHA1_HEXSZ + 6; /* "tree " + "hex sha1" + "\n" */
325 parent_end = parent_start;
326
327 while (starts_with(parent_end, "parent "))
328 parent_end += 48; /* "parent " + "hex sha1" + "\n" */
329
330 /* prepare new parents */
331 for (i = 0; i < argc; i++) {
332 struct object_id oid;
333 if (get_oid(argv[i], &oid) < 0)
334 die(_("Not a valid object name: '%s'"), argv[i]);
335 lookup_commit_or_die(&oid, argv[i]);
336 strbuf_addf(&new_parents, "parent %s\n", oid_to_hex(&oid));
337 }
338
339 /* replace existing parents with new ones */
340 strbuf_splice(buf, parent_start - buf->buf, parent_end - parent_start,
341 new_parents.buf, new_parents.len);
342
343 strbuf_release(&new_parents);
344 }
345
346 struct check_mergetag_data {
347 int argc;
348 const char **argv;
349 };
350
351 static void check_one_mergetag(struct commit *commit,
352 struct commit_extra_header *extra,
353 void *data)
354 {
355 struct check_mergetag_data *mergetag_data = (struct check_mergetag_data *)data;
356 const char *ref = mergetag_data->argv[0];
357 struct object_id tag_oid;
358 struct tag *tag;
359 int i;
360
361 hash_object_file(extra->value, extra->len, type_name(OBJ_TAG), &tag_oid);
362 tag = lookup_tag(&tag_oid);
363 if (!tag)
364 die(_("bad mergetag in commit '%s'"), ref);
365 if (parse_tag_buffer(tag, extra->value, extra->len))
366 die(_("malformed mergetag in commit '%s'"), ref);
367
368 /* iterate over new parents */
369 for (i = 1; i < mergetag_data->argc; i++) {
370 struct object_id oid;
371 if (get_oid(mergetag_data->argv[i], &oid) < 0)
372 die(_("Not a valid object name: '%s'"), mergetag_data->argv[i]);
373 if (!oidcmp(&tag->tagged->oid, &oid))
374 return; /* found */
375 }
376
377 die(_("original commit '%s' contains mergetag '%s' that is discarded; "
378 "use --edit instead of --graft"), ref, oid_to_hex(&tag_oid));
379 }
380
381 static void check_mergetags(struct commit *commit, int argc, const char **argv)
382 {
383 struct check_mergetag_data mergetag_data;
384
385 mergetag_data.argc = argc;
386 mergetag_data.argv = argv;
387 for_each_mergetag(check_one_mergetag, commit, &mergetag_data);
388 }
389
390 static int create_graft(int argc, const char **argv, int force)
391 {
392 struct object_id old_oid, new_oid;
393 const char *old_ref = argv[0];
394 struct commit *commit;
395 struct strbuf buf = STRBUF_INIT;
396 const char *buffer;
397 unsigned long size;
398
399 if (get_oid(old_ref, &old_oid) < 0)
400 die(_("Not a valid object name: '%s'"), old_ref);
401 commit = lookup_commit_or_die(&old_oid, old_ref);
402
403 buffer = get_commit_buffer(commit, &size);
404 strbuf_add(&buf, buffer, size);
405 unuse_commit_buffer(commit, buffer);
406
407 replace_parents(&buf, argc - 1, &argv[1]);
408
409 if (remove_signature(&buf)) {
410 warning(_("the original commit '%s' has a gpg signature."), old_ref);
411 warning(_("the signature will be removed in the replacement commit!"));
412 }
413
414 check_mergetags(commit, argc, argv);
415
416 if (write_object_file(buf.buf, buf.len, commit_type, &new_oid))
417 die(_("could not write replacement commit for: '%s'"), old_ref);
418
419 strbuf_release(&buf);
420
421 if (!oidcmp(&old_oid, &new_oid))
422 return error("new commit is the same as the old one: '%s'", oid_to_hex(&old_oid));
423
424 return replace_object_oid(old_ref, &old_oid, "replacement", &new_oid, force);
425 }
426
427 int cmd_replace(int argc, const char **argv, const char *prefix)
428 {
429 int force = 0;
430 int raw = 0;
431 const char *format = NULL;
432 enum {
433 MODE_UNSPECIFIED = 0,
434 MODE_LIST,
435 MODE_DELETE,
436 MODE_EDIT,
437 MODE_GRAFT,
438 MODE_REPLACE
439 } cmdmode = MODE_UNSPECIFIED;
440 struct option options[] = {
441 OPT_CMDMODE('l', "list", &cmdmode, N_("list replace refs"), MODE_LIST),
442 OPT_CMDMODE('d', "delete", &cmdmode, N_("delete replace refs"), MODE_DELETE),
443 OPT_CMDMODE('e', "edit", &cmdmode, N_("edit existing object"), MODE_EDIT),
444 OPT_CMDMODE('g', "graft", &cmdmode, N_("change a commit's parents"), MODE_GRAFT),
445 OPT_BOOL_F('f', "force", &force, N_("replace the ref if it exists"),
446 PARSE_OPT_NOCOMPLETE),
447 OPT_BOOL(0, "raw", &raw, N_("do not pretty-print contents for --edit")),
448 OPT_STRING(0, "format", &format, N_("format"), N_("use this format")),
449 OPT_END()
450 };
451
452 check_replace_refs = 0;
453 git_config(git_default_config, NULL);
454
455 argc = parse_options(argc, argv, prefix, options, git_replace_usage, 0);
456
457 if (!cmdmode)
458 cmdmode = argc ? MODE_REPLACE : MODE_LIST;
459
460 if (format && cmdmode != MODE_LIST)
461 usage_msg_opt("--format cannot be used when not listing",
462 git_replace_usage, options);
463
464 if (force &&
465 cmdmode != MODE_REPLACE &&
466 cmdmode != MODE_EDIT &&
467 cmdmode != MODE_GRAFT)
468 usage_msg_opt("-f only makes sense when writing a replacement",
469 git_replace_usage, options);
470
471 if (raw && cmdmode != MODE_EDIT)
472 usage_msg_opt("--raw only makes sense with --edit",
473 git_replace_usage, options);
474
475 switch (cmdmode) {
476 case MODE_DELETE:
477 if (argc < 1)
478 usage_msg_opt("-d needs at least one argument",
479 git_replace_usage, options);
480 return for_each_replace_name(argv, delete_replace_ref);
481
482 case MODE_REPLACE:
483 if (argc != 2)
484 usage_msg_opt("bad number of arguments",
485 git_replace_usage, options);
486 return replace_object(argv[0], argv[1], force);
487
488 case MODE_EDIT:
489 if (argc != 1)
490 usage_msg_opt("-e needs exactly one argument",
491 git_replace_usage, options);
492 return edit_and_replace(argv[0], force, raw);
493
494 case MODE_GRAFT:
495 if (argc < 1)
496 usage_msg_opt("-g needs at least one argument",
497 git_replace_usage, options);
498 return create_graft(argc, argv, force);
499
500 case MODE_LIST:
501 if (argc > 1)
502 usage_msg_opt("only one pattern can be given with -l",
503 git_replace_usage, options);
504 return list_replace_refs(argv[0], format);
505
506 default:
507 die("BUG: invalid cmdmode %d", (int)cmdmode);
508 }
509 }