Merge branch 'rs/retire-strbuf-write-fd'
[git] / builtin / reset.c
1 /*
2  * "git reset" builtin command
3  *
4  * Copyright (c) 2007 Carlos Rica
5  *
6  * Based on git-reset.sh, which is
7  *
8  * Copyright (c) 2005, 2006 Linus Torvalds and Junio C Hamano
9  */
10 #define USE_THE_INDEX_COMPATIBILITY_MACROS
11 #include "builtin.h"
12 #include "config.h"
13 #include "lockfile.h"
14 #include "tag.h"
15 #include "object.h"
16 #include "pretty.h"
17 #include "run-command.h"
18 #include "refs.h"
19 #include "diff.h"
20 #include "diffcore.h"
21 #include "tree.h"
22 #include "branch.h"
23 #include "parse-options.h"
24 #include "unpack-trees.h"
25 #include "cache-tree.h"
26 #include "submodule.h"
27 #include "submodule-config.h"
28
29 #define REFRESH_INDEX_DELAY_WARNING_IN_MS (2 * 1000)
30
31 static const char * const git_reset_usage[] = {
32         N_("git reset [--mixed | --soft | --hard | --merge | --keep] [-q] [<commit>]"),
33         N_("git reset [-q] [<tree-ish>] [--] <pathspec>..."),
34         N_("git reset [-q] [--pathspec-from-file [--pathspec-file-nul]] [<tree-ish>]"),
35         N_("git reset --patch [<tree-ish>] [--] [<pathspec>...]"),
36         NULL
37 };
38
39 enum reset_type { MIXED, SOFT, HARD, MERGE, KEEP, NONE };
40 static const char *reset_type_names[] = {
41         N_("mixed"), N_("soft"), N_("hard"), N_("merge"), N_("keep"), NULL
42 };
43
44 static inline int is_merge(void)
45 {
46         return !access(git_path_merge_head(the_repository), F_OK);
47 }
48
49 static int reset_index(const char *ref, const struct object_id *oid, int reset_type, int quiet)
50 {
51         int i, nr = 0;
52         struct tree_desc desc[2];
53         struct tree *tree;
54         struct unpack_trees_options opts;
55         int ret = -1;
56
57         memset(&opts, 0, sizeof(opts));
58         opts.head_idx = 1;
59         opts.src_index = &the_index;
60         opts.dst_index = &the_index;
61         opts.fn = oneway_merge;
62         opts.merge = 1;
63         init_checkout_metadata(&opts.meta, ref, oid, NULL);
64         if (!quiet)
65                 opts.verbose_update = 1;
66         switch (reset_type) {
67         case KEEP:
68         case MERGE:
69                 opts.update = 1;
70                 break;
71         case HARD:
72                 opts.update = 1;
73                 /* fallthrough */
74         default:
75                 opts.reset = 1;
76         }
77
78         read_cache_unmerged();
79
80         if (reset_type == KEEP) {
81                 struct object_id head_oid;
82                 if (get_oid("HEAD", &head_oid))
83                         return error(_("You do not have a valid HEAD."));
84                 if (!fill_tree_descriptor(the_repository, desc + nr, &head_oid))
85                         return error(_("Failed to find tree of HEAD."));
86                 nr++;
87                 opts.fn = twoway_merge;
88         }
89
90         if (!fill_tree_descriptor(the_repository, desc + nr, oid)) {
91                 error(_("Failed to find tree of %s."), oid_to_hex(oid));
92                 goto out;
93         }
94         nr++;
95
96         if (unpack_trees(nr, desc, &opts))
97                 goto out;
98
99         if (reset_type == MIXED || reset_type == HARD) {
100                 tree = parse_tree_indirect(oid);
101                 prime_cache_tree(the_repository, the_repository->index, tree);
102         }
103
104         ret = 0;
105
106 out:
107         for (i = 0; i < nr; i++)
108                 free((void *)desc[i].buffer);
109         return ret;
110 }
111
112 static void print_new_head_line(struct commit *commit)
113 {
114         struct strbuf buf = STRBUF_INIT;
115
116         printf(_("HEAD is now at %s"),
117                 find_unique_abbrev(&commit->object.oid, DEFAULT_ABBREV));
118
119         pp_commit_easy(CMIT_FMT_ONELINE, commit, &buf);
120         if (buf.len > 0)
121                 printf(" %s", buf.buf);
122         putchar('\n');
123         strbuf_release(&buf);
124 }
125
126 static void update_index_from_diff(struct diff_queue_struct *q,
127                 struct diff_options *opt, void *data)
128 {
129         int i;
130         int intent_to_add = *(int *)data;
131
132         for (i = 0; i < q->nr; i++) {
133                 struct diff_filespec *one = q->queue[i]->one;
134                 int is_missing = !(one->mode && !is_null_oid(&one->oid));
135                 struct cache_entry *ce;
136
137                 if (is_missing && !intent_to_add) {
138                         remove_file_from_cache(one->path);
139                         continue;
140                 }
141
142                 ce = make_cache_entry(&the_index, one->mode, &one->oid, one->path,
143                                       0, 0);
144                 if (!ce)
145                         die(_("make_cache_entry failed for path '%s'"),
146                             one->path);
147                 if (is_missing) {
148                         ce->ce_flags |= CE_INTENT_TO_ADD;
149                         set_object_name_for_intent_to_add_entry(ce);
150                 }
151                 add_cache_entry(ce, ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE);
152         }
153 }
154
155 static int read_from_tree(const struct pathspec *pathspec,
156                           struct object_id *tree_oid,
157                           int intent_to_add)
158 {
159         struct diff_options opt;
160
161         memset(&opt, 0, sizeof(opt));
162         copy_pathspec(&opt.pathspec, pathspec);
163         opt.output_format = DIFF_FORMAT_CALLBACK;
164         opt.format_callback = update_index_from_diff;
165         opt.format_callback_data = &intent_to_add;
166         opt.flags.override_submodule_config = 1;
167         opt.repo = the_repository;
168
169         if (do_diff_cache(tree_oid, &opt))
170                 return 1;
171         diffcore_std(&opt);
172         diff_flush(&opt);
173         clear_pathspec(&opt.pathspec);
174
175         return 0;
176 }
177
178 static void set_reflog_message(struct strbuf *sb, const char *action,
179                                const char *rev)
180 {
181         const char *rla = getenv("GIT_REFLOG_ACTION");
182
183         strbuf_reset(sb);
184         if (rla)
185                 strbuf_addf(sb, "%s: %s", rla, action);
186         else if (rev)
187                 strbuf_addf(sb, "reset: moving to %s", rev);
188         else
189                 strbuf_addf(sb, "reset: %s", action);
190 }
191
192 static void die_if_unmerged_cache(int reset_type)
193 {
194         if (is_merge() || unmerged_cache())
195                 die(_("Cannot do a %s reset in the middle of a merge."),
196                     _(reset_type_names[reset_type]));
197
198 }
199
200 static void parse_args(struct pathspec *pathspec,
201                        const char **argv, const char *prefix,
202                        int patch_mode,
203                        const char **rev_ret)
204 {
205         const char *rev = "HEAD";
206         struct object_id unused;
207         /*
208          * Possible arguments are:
209          *
210          * git reset [-opts] [<rev>]
211          * git reset [-opts] <tree> [<paths>...]
212          * git reset [-opts] <tree> -- [<paths>...]
213          * git reset [-opts] -- [<paths>...]
214          * git reset [-opts] <paths>...
215          *
216          * At this point, argv points immediately after [-opts].
217          */
218
219         if (argv[0]) {
220                 if (!strcmp(argv[0], "--")) {
221                         argv++; /* reset to HEAD, possibly with paths */
222                 } else if (argv[1] && !strcmp(argv[1], "--")) {
223                         rev = argv[0];
224                         argv += 2;
225                 }
226                 /*
227                  * Otherwise, argv[0] could be either <rev> or <paths> and
228                  * has to be unambiguous. If there is a single argument, it
229                  * can not be a tree
230                  */
231                 else if ((!argv[1] && !get_oid_committish(argv[0], &unused)) ||
232                          (argv[1] && !get_oid_treeish(argv[0], &unused))) {
233                         /*
234                          * Ok, argv[0] looks like a commit/tree; it should not
235                          * be a filename.
236                          */
237                         verify_non_filename(prefix, argv[0]);
238                         rev = *argv++;
239                 } else {
240                         /* Otherwise we treat this as a filename */
241                         verify_filename(prefix, argv[0], 1);
242                 }
243         }
244         *rev_ret = rev;
245
246         if (read_cache() < 0)
247                 die(_("index file corrupt"));
248
249         parse_pathspec(pathspec, 0,
250                        PATHSPEC_PREFER_FULL |
251                        (patch_mode ? PATHSPEC_PREFIX_ORIGIN : 0),
252                        prefix, argv);
253 }
254
255 static int reset_refs(const char *rev, const struct object_id *oid)
256 {
257         int update_ref_status;
258         struct strbuf msg = STRBUF_INIT;
259         struct object_id *orig = NULL, oid_orig,
260                 *old_orig = NULL, oid_old_orig;
261
262         if (!get_oid("ORIG_HEAD", &oid_old_orig))
263                 old_orig = &oid_old_orig;
264         if (!get_oid("HEAD", &oid_orig)) {
265                 orig = &oid_orig;
266                 set_reflog_message(&msg, "updating ORIG_HEAD", NULL);
267                 update_ref(msg.buf, "ORIG_HEAD", orig, old_orig, 0,
268                            UPDATE_REFS_MSG_ON_ERR);
269         } else if (old_orig)
270                 delete_ref(NULL, "ORIG_HEAD", old_orig, 0);
271         set_reflog_message(&msg, "updating HEAD", rev);
272         update_ref_status = update_ref(msg.buf, "HEAD", oid, orig, 0,
273                                        UPDATE_REFS_MSG_ON_ERR);
274         strbuf_release(&msg);
275         return update_ref_status;
276 }
277
278 static int git_reset_config(const char *var, const char *value, void *cb)
279 {
280         if (!strcmp(var, "submodule.recurse"))
281                 return git_default_submodule_config(var, value, cb);
282
283         return git_default_config(var, value, cb);
284 }
285
286 int cmd_reset(int argc, const char **argv, const char *prefix)
287 {
288         int reset_type = NONE, update_ref_status = 0, quiet = 0;
289         int patch_mode = 0, pathspec_file_nul = 0, unborn;
290         const char *rev, *pathspec_from_file = NULL;
291         struct object_id oid;
292         struct pathspec pathspec;
293         int intent_to_add = 0;
294         const struct option options[] = {
295                 OPT__QUIET(&quiet, N_("be quiet, only report errors")),
296                 OPT_SET_INT(0, "mixed", &reset_type,
297                                                 N_("reset HEAD and index"), MIXED),
298                 OPT_SET_INT(0, "soft", &reset_type, N_("reset only HEAD"), SOFT),
299                 OPT_SET_INT(0, "hard", &reset_type,
300                                 N_("reset HEAD, index and working tree"), HARD),
301                 OPT_SET_INT(0, "merge", &reset_type,
302                                 N_("reset HEAD, index and working tree"), MERGE),
303                 OPT_SET_INT(0, "keep", &reset_type,
304                                 N_("reset HEAD but keep local changes"), KEEP),
305                 OPT_CALLBACK_F(0, "recurse-submodules", NULL,
306                             "reset", "control recursive updating of submodules",
307                             PARSE_OPT_OPTARG, option_parse_recurse_submodules_worktree_updater),
308                 OPT_BOOL('p', "patch", &patch_mode, N_("select hunks interactively")),
309                 OPT_BOOL('N', "intent-to-add", &intent_to_add,
310                                 N_("record only the fact that removed paths will be added later")),
311                 OPT_PATHSPEC_FROM_FILE(&pathspec_from_file),
312                 OPT_PATHSPEC_FILE_NUL(&pathspec_file_nul),
313                 OPT_END()
314         };
315
316         git_config(git_reset_config, NULL);
317         git_config_get_bool("reset.quiet", &quiet);
318
319         argc = parse_options(argc, argv, prefix, options, git_reset_usage,
320                                                 PARSE_OPT_KEEP_DASHDASH);
321         parse_args(&pathspec, argv, prefix, patch_mode, &rev);
322
323         if (pathspec_from_file) {
324                 if (patch_mode)
325                         die(_("--pathspec-from-file is incompatible with --patch"));
326
327                 if (pathspec.nr)
328                         die(_("--pathspec-from-file is incompatible with pathspec arguments"));
329
330                 parse_pathspec_file(&pathspec, 0,
331                                     PATHSPEC_PREFER_FULL,
332                                     prefix, pathspec_from_file, pathspec_file_nul);
333         } else if (pathspec_file_nul) {
334                 die(_("--pathspec-file-nul requires --pathspec-from-file"));
335         }
336
337         unborn = !strcmp(rev, "HEAD") && get_oid("HEAD", &oid);
338         if (unborn) {
339                 /* reset on unborn branch: treat as reset to empty tree */
340                 oidcpy(&oid, the_hash_algo->empty_tree);
341         } else if (!pathspec.nr && !patch_mode) {
342                 struct commit *commit;
343                 if (get_oid_committish(rev, &oid))
344                         die(_("Failed to resolve '%s' as a valid revision."), rev);
345                 commit = lookup_commit_reference(the_repository, &oid);
346                 if (!commit)
347                         die(_("Could not parse object '%s'."), rev);
348                 oidcpy(&oid, &commit->object.oid);
349         } else {
350                 struct tree *tree;
351                 if (get_oid_treeish(rev, &oid))
352                         die(_("Failed to resolve '%s' as a valid tree."), rev);
353                 tree = parse_tree_indirect(&oid);
354                 if (!tree)
355                         die(_("Could not parse object '%s'."), rev);
356                 oidcpy(&oid, &tree->object.oid);
357         }
358
359         if (patch_mode) {
360                 if (reset_type != NONE)
361                         die(_("--patch is incompatible with --{hard,mixed,soft}"));
362                 trace2_cmd_mode("patch-interactive");
363                 return run_add_interactive(rev, "--patch=reset", &pathspec);
364         }
365
366         /* git reset tree [--] paths... can be used to
367          * load chosen paths from the tree into the index without
368          * affecting the working tree nor HEAD. */
369         if (pathspec.nr) {
370                 if (reset_type == MIXED)
371                         warning(_("--mixed with paths is deprecated; use 'git reset -- <paths>' instead."));
372                 else if (reset_type != NONE)
373                         die(_("Cannot do %s reset with paths."),
374                                         _(reset_type_names[reset_type]));
375         }
376         if (reset_type == NONE)
377                 reset_type = MIXED; /* by default */
378
379         if (pathspec.nr)
380                 trace2_cmd_mode("path");
381         else
382                 trace2_cmd_mode(reset_type_names[reset_type]);
383
384         if (reset_type != SOFT && (reset_type != MIXED || get_git_work_tree()))
385                 setup_work_tree();
386
387         if (reset_type == MIXED && is_bare_repository())
388                 die(_("%s reset is not allowed in a bare repository"),
389                     _(reset_type_names[reset_type]));
390
391         if (intent_to_add && reset_type != MIXED)
392                 die(_("-N can only be used with --mixed"));
393
394         /* Soft reset does not touch the index file nor the working tree
395          * at all, but requires them in a good order.  Other resets reset
396          * the index file to the tree object we are switching to. */
397         if (reset_type == SOFT || reset_type == KEEP)
398                 die_if_unmerged_cache(reset_type);
399
400         if (reset_type != SOFT) {
401                 struct lock_file lock = LOCK_INIT;
402                 hold_locked_index(&lock, LOCK_DIE_ON_ERROR);
403                 if (reset_type == MIXED) {
404                         int flags = quiet ? REFRESH_QUIET : REFRESH_IN_PORCELAIN;
405                         if (read_from_tree(&pathspec, &oid, intent_to_add))
406                                 return 1;
407                         the_index.updated_skipworktree = 1;
408                         if (!quiet && get_git_work_tree()) {
409                                 uint64_t t_begin, t_delta_in_ms;
410
411                                 t_begin = getnanotime();
412                                 refresh_index(&the_index, flags, NULL, NULL,
413                                               _("Unstaged changes after reset:"));
414                                 t_delta_in_ms = (getnanotime() - t_begin) / 1000000;
415                                 if (advice_reset_quiet_warning && t_delta_in_ms > REFRESH_INDEX_DELAY_WARNING_IN_MS) {
416                                         printf(_("\nIt took %.2f seconds to enumerate unstaged changes after reset.  You can\n"
417                                                 "use '--quiet' to avoid this.  Set the config setting reset.quiet to true\n"
418                                                 "to make this the default.\n"), t_delta_in_ms / 1000.0);
419                                 }
420                         }
421                 } else {
422                         struct object_id dummy;
423                         char *ref = NULL;
424                         int err;
425
426                         dwim_ref(rev, strlen(rev), &dummy, &ref);
427                         if (ref && !starts_with(ref, "refs/"))
428                                 ref = NULL;
429
430                         err = reset_index(ref, &oid, reset_type, quiet);
431                         if (reset_type == KEEP && !err)
432                                 err = reset_index(ref, &oid, MIXED, quiet);
433                         if (err)
434                                 die(_("Could not reset index file to revision '%s'."), rev);
435                         free(ref);
436                 }
437
438                 if (write_locked_index(&the_index, &lock, COMMIT_LOCK))
439                         die(_("Could not write new index file."));
440         }
441
442         if (!pathspec.nr && !unborn) {
443                 /* Any resets without paths update HEAD to the head being
444                  * switched to, saving the previous head in ORIG_HEAD before. */
445                 update_ref_status = reset_refs(rev, &oid);
446
447                 if (reset_type == HARD && !update_ref_status && !quiet)
448                         print_new_head_line(lookup_commit_reference(the_repository, &oid));
449         }
450         if (!pathspec.nr)
451                 remove_branch_state(the_repository, 0);
452
453         return update_ref_status;
454 }