Sync with Git 2.14.4
[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 #include "builtin.h"
11 #include "config.h"
12 #include "lockfile.h"
13 #include "tag.h"
14 #include "object.h"
15 #include "commit.h"
16 #include "run-command.h"
17 #include "refs.h"
18 #include "diff.h"
19 #include "diffcore.h"
20 #include "tree.h"
21 #include "branch.h"
22 #include "parse-options.h"
23 #include "unpack-trees.h"
24 #include "cache-tree.h"
25 #include "submodule.h"
26 #include "submodule-config.h"
27
28 static const char * const git_reset_usage[] = {
29         N_("git reset [--mixed | --soft | --hard | --merge | --keep] [-q] [<commit>]"),
30         N_("git reset [-q] [<tree-ish>] [--] <paths>..."),
31         N_("git reset --patch [<tree-ish>] [--] [<paths>...]"),
32         NULL
33 };
34
35 enum reset_type { MIXED, SOFT, HARD, MERGE, KEEP, NONE };
36 static const char *reset_type_names[] = {
37         N_("mixed"), N_("soft"), N_("hard"), N_("merge"), N_("keep"), NULL
38 };
39
40 static inline int is_merge(void)
41 {
42         return !access(git_path_merge_head(), F_OK);
43 }
44
45 static int reset_index(const struct object_id *oid, int reset_type, int quiet)
46 {
47         int i, nr = 0;
48         struct tree_desc desc[2];
49         struct tree *tree;
50         struct unpack_trees_options opts;
51         int ret = -1;
52
53         memset(&opts, 0, sizeof(opts));
54         opts.head_idx = 1;
55         opts.src_index = &the_index;
56         opts.dst_index = &the_index;
57         opts.fn = oneway_merge;
58         opts.merge = 1;
59         if (!quiet)
60                 opts.verbose_update = 1;
61         switch (reset_type) {
62         case KEEP:
63         case MERGE:
64                 opts.update = 1;
65                 break;
66         case HARD:
67                 opts.update = 1;
68                 /* fallthrough */
69         default:
70                 opts.reset = 1;
71         }
72
73         read_cache_unmerged();
74
75         if (reset_type == KEEP) {
76                 struct object_id head_oid;
77                 if (get_oid("HEAD", &head_oid))
78                         return error(_("You do not have a valid HEAD."));
79                 if (!fill_tree_descriptor(desc + nr, &head_oid))
80                         return error(_("Failed to find tree of HEAD."));
81                 nr++;
82                 opts.fn = twoway_merge;
83         }
84
85         if (!fill_tree_descriptor(desc + nr, oid)) {
86                 error(_("Failed to find tree of %s."), oid_to_hex(oid));
87                 goto out;
88         }
89         nr++;
90
91         if (unpack_trees(nr, desc, &opts))
92                 goto out;
93
94         if (reset_type == MIXED || reset_type == HARD) {
95                 tree = parse_tree_indirect(oid);
96                 prime_cache_tree(&the_index, tree);
97         }
98
99         ret = 0;
100
101 out:
102         for (i = 0; i < nr; i++)
103                 free((void *)desc[i].buffer);
104         return ret;
105 }
106
107 static void print_new_head_line(struct commit *commit)
108 {
109         const char *hex, *body;
110         const char *msg;
111
112         hex = find_unique_abbrev(commit->object.oid.hash, DEFAULT_ABBREV);
113         printf(_("HEAD is now at %s"), hex);
114         msg = logmsg_reencode(commit, NULL, get_log_output_encoding());
115         body = strstr(msg, "\n\n");
116         if (body) {
117                 const char *eol;
118                 size_t len;
119                 body = skip_blank_lines(body + 2);
120                 eol = strchr(body, '\n');
121                 len = eol ? eol - body : strlen(body);
122                 printf(" %.*s\n", (int) len, body);
123         }
124         else
125                 printf("\n");
126         unuse_commit_buffer(commit, msg);
127 }
128
129 static void update_index_from_diff(struct diff_queue_struct *q,
130                 struct diff_options *opt, void *data)
131 {
132         int i;
133         int intent_to_add = *(int *)data;
134
135         for (i = 0; i < q->nr; i++) {
136                 struct diff_filespec *one = q->queue[i]->one;
137                 int is_missing = !(one->mode && !is_null_oid(&one->oid));
138                 struct cache_entry *ce;
139
140                 if (is_missing && !intent_to_add) {
141                         remove_file_from_cache(one->path);
142                         continue;
143                 }
144
145                 ce = make_cache_entry(one->mode, one->oid.hash, one->path,
146                                       0, 0);
147                 if (!ce)
148                         die(_("make_cache_entry failed for path '%s'"),
149                             one->path);
150                 if (is_missing) {
151                         ce->ce_flags |= CE_INTENT_TO_ADD;
152                         set_object_name_for_intent_to_add_entry(ce);
153                 }
154                 add_cache_entry(ce, ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE);
155         }
156 }
157
158 static int read_from_tree(const struct pathspec *pathspec,
159                           struct object_id *tree_oid,
160                           int intent_to_add)
161 {
162         struct diff_options opt;
163
164         memset(&opt, 0, sizeof(opt));
165         copy_pathspec(&opt.pathspec, pathspec);
166         opt.output_format = DIFF_FORMAT_CALLBACK;
167         opt.format_callback = update_index_from_diff;
168         opt.format_callback_data = &intent_to_add;
169         opt.flags |= DIFF_OPT_OVERRIDE_SUBMODULE_CONFIG;
170
171         if (do_diff_cache(tree_oid, &opt))
172                 return 1;
173         diffcore_std(&opt);
174         diff_flush(&opt);
175         clear_pathspec(&opt.pathspec);
176
177         return 0;
178 }
179
180 static void set_reflog_message(struct strbuf *sb, const char *action,
181                                const char *rev)
182 {
183         const char *rla = getenv("GIT_REFLOG_ACTION");
184
185         strbuf_reset(sb);
186         if (rla)
187                 strbuf_addf(sb, "%s: %s", rla, action);
188         else if (rev)
189                 strbuf_addf(sb, "reset: moving to %s", rev);
190         else
191                 strbuf_addf(sb, "reset: %s", action);
192 }
193
194 static void die_if_unmerged_cache(int reset_type)
195 {
196         if (is_merge() || unmerged_cache())
197                 die(_("Cannot do a %s reset in the middle of a merge."),
198                     _(reset_type_names[reset_type]));
199
200 }
201
202 static void parse_args(struct pathspec *pathspec,
203                        const char **argv, const char *prefix,
204                        int patch_mode,
205                        const char **rev_ret)
206 {
207         const char *rev = "HEAD";
208         struct object_id unused;
209         /*
210          * Possible arguments are:
211          *
212          * git reset [-opts] [<rev>]
213          * git reset [-opts] <tree> [<paths>...]
214          * git reset [-opts] <tree> -- [<paths>...]
215          * git reset [-opts] -- [<paths>...]
216          * git reset [-opts] <paths>...
217          *
218          * At this point, argv points immediately after [-opts].
219          */
220
221         if (argv[0]) {
222                 if (!strcmp(argv[0], "--")) {
223                         argv++; /* reset to HEAD, possibly with paths */
224                 } else if (argv[1] && !strcmp(argv[1], "--")) {
225                         rev = argv[0];
226                         argv += 2;
227                 }
228                 /*
229                  * Otherwise, argv[0] could be either <rev> or <paths> and
230                  * has to be unambiguous. If there is a single argument, it
231                  * can not be a tree
232                  */
233                 else if ((!argv[1] && !get_oid_committish(argv[0], &unused)) ||
234                          (argv[1] && !get_oid_treeish(argv[0], &unused))) {
235                         /*
236                          * Ok, argv[0] looks like a commit/tree; it should not
237                          * be a filename.
238                          */
239                         verify_non_filename(prefix, argv[0]);
240                         rev = *argv++;
241                 } else {
242                         /* Otherwise we treat this as a filename */
243                         verify_filename(prefix, argv[0], 1);
244                 }
245         }
246         *rev_ret = rev;
247
248         if (read_cache() < 0)
249                 die(_("index file corrupt"));
250
251         parse_pathspec(pathspec, 0,
252                        PATHSPEC_PREFER_FULL |
253                        (patch_mode ? PATHSPEC_PREFIX_ORIGIN : 0),
254                        prefix, argv);
255 }
256
257 static int reset_refs(const char *rev, const struct object_id *oid)
258 {
259         int update_ref_status;
260         struct strbuf msg = STRBUF_INIT;
261         struct object_id *orig = NULL, oid_orig,
262                 *old_orig = NULL, oid_old_orig;
263
264         if (!get_oid("ORIG_HEAD", &oid_old_orig))
265                 old_orig = &oid_old_orig;
266         if (!get_oid("HEAD", &oid_orig)) {
267                 orig = &oid_orig;
268                 set_reflog_message(&msg, "updating ORIG_HEAD", NULL);
269                 update_ref_oid(msg.buf, "ORIG_HEAD", orig, old_orig, 0,
270                            UPDATE_REFS_MSG_ON_ERR);
271         } else if (old_orig)
272                 delete_ref(NULL, "ORIG_HEAD", old_orig->hash, 0);
273         set_reflog_message(&msg, "updating HEAD", rev);
274         update_ref_status = update_ref_oid(msg.buf, "HEAD", oid, orig, 0,
275                                        UPDATE_REFS_MSG_ON_ERR);
276         strbuf_release(&msg);
277         return update_ref_status;
278 }
279
280 static int git_reset_config(const char *var, const char *value, void *cb)
281 {
282         if (!strcmp(var, "submodule.recurse"))
283                 return git_default_submodule_config(var, value, cb);
284
285         return git_default_config(var, value, cb);
286 }
287
288 int cmd_reset(int argc, const char **argv, const char *prefix)
289 {
290         int reset_type = NONE, update_ref_status = 0, quiet = 0;
291         int patch_mode = 0, unborn;
292         const char *rev;
293         struct object_id oid;
294         struct pathspec pathspec;
295         int intent_to_add = 0;
296         const struct option options[] = {
297                 OPT__QUIET(&quiet, N_("be quiet, only report errors")),
298                 OPT_SET_INT(0, "mixed", &reset_type,
299                                                 N_("reset HEAD and index"), MIXED),
300                 OPT_SET_INT(0, "soft", &reset_type, N_("reset only HEAD"), SOFT),
301                 OPT_SET_INT(0, "hard", &reset_type,
302                                 N_("reset HEAD, index and working tree"), HARD),
303                 OPT_SET_INT(0, "merge", &reset_type,
304                                 N_("reset HEAD, index and working tree"), MERGE),
305                 OPT_SET_INT(0, "keep", &reset_type,
306                                 N_("reset HEAD but keep local changes"), KEEP),
307                 { OPTION_CALLBACK, 0, "recurse-submodules", NULL,
308                             "reset", "control recursive updating of submodules",
309                             PARSE_OPT_OPTARG, option_parse_recurse_submodules_worktree_updater },
310                 OPT_BOOL('p', "patch", &patch_mode, N_("select hunks interactively")),
311                 OPT_BOOL('N', "intent-to-add", &intent_to_add,
312                                 N_("record only the fact that removed paths will be added later")),
313                 OPT_END()
314         };
315
316         git_config(git_reset_config, NULL);
317
318         argc = parse_options(argc, argv, prefix, options, git_reset_usage,
319                                                 PARSE_OPT_KEEP_DASHDASH);
320         parse_args(&pathspec, argv, prefix, patch_mode, &rev);
321
322         unborn = !strcmp(rev, "HEAD") && get_oid("HEAD", &oid);
323         if (unborn) {
324                 /* reset on unborn branch: treat as reset to empty tree */
325                 hashcpy(oid.hash, EMPTY_TREE_SHA1_BIN);
326         } else if (!pathspec.nr) {
327                 struct commit *commit;
328                 if (get_oid_committish(rev, &oid))
329                         die(_("Failed to resolve '%s' as a valid revision."), rev);
330                 commit = lookup_commit_reference(&oid);
331                 if (!commit)
332                         die(_("Could not parse object '%s'."), rev);
333                 oidcpy(&oid, &commit->object.oid);
334         } else {
335                 struct tree *tree;
336                 if (get_oid_treeish(rev, &oid))
337                         die(_("Failed to resolve '%s' as a valid tree."), rev);
338                 tree = parse_tree_indirect(&oid);
339                 if (!tree)
340                         die(_("Could not parse object '%s'."), rev);
341                 oidcpy(&oid, &tree->object.oid);
342         }
343
344         if (patch_mode) {
345                 if (reset_type != NONE)
346                         die(_("--patch is incompatible with --{hard,mixed,soft}"));
347                 return run_add_interactive(rev, "--patch=reset", &pathspec);
348         }
349
350         /* git reset tree [--] paths... can be used to
351          * load chosen paths from the tree into the index without
352          * affecting the working tree nor HEAD. */
353         if (pathspec.nr) {
354                 if (reset_type == MIXED)
355                         warning(_("--mixed with paths is deprecated; use 'git reset -- <paths>' instead."));
356                 else if (reset_type != NONE)
357                         die(_("Cannot do %s reset with paths."),
358                                         _(reset_type_names[reset_type]));
359         }
360         if (reset_type == NONE)
361                 reset_type = MIXED; /* by default */
362
363         if (reset_type != SOFT && (reset_type != MIXED || get_git_work_tree()))
364                 setup_work_tree();
365
366         if (reset_type == MIXED && is_bare_repository())
367                 die(_("%s reset is not allowed in a bare repository"),
368                     _(reset_type_names[reset_type]));
369
370         if (intent_to_add && reset_type != MIXED)
371                 die(_("-N can only be used with --mixed"));
372
373         /* Soft reset does not touch the index file nor the working tree
374          * at all, but requires them in a good order.  Other resets reset
375          * the index file to the tree object we are switching to. */
376         if (reset_type == SOFT || reset_type == KEEP)
377                 die_if_unmerged_cache(reset_type);
378
379         if (reset_type != SOFT) {
380                 struct lock_file lock = LOCK_INIT;
381                 hold_locked_index(&lock, LOCK_DIE_ON_ERROR);
382                 if (reset_type == MIXED) {
383                         int flags = quiet ? REFRESH_QUIET : REFRESH_IN_PORCELAIN;
384                         if (read_from_tree(&pathspec, &oid, intent_to_add))
385                                 return 1;
386                         if (get_git_work_tree())
387                                 refresh_index(&the_index, flags, NULL, NULL,
388                                               _("Unstaged changes after reset:"));
389                 } else {
390                         int err = reset_index(&oid, reset_type, quiet);
391                         if (reset_type == KEEP && !err)
392                                 err = reset_index(&oid, MIXED, quiet);
393                         if (err)
394                                 die(_("Could not reset index file to revision '%s'."), rev);
395                 }
396
397                 if (write_locked_index(&the_index, &lock, COMMIT_LOCK))
398                         die(_("Could not write new index file."));
399         }
400
401         if (!pathspec.nr && !unborn) {
402                 /* Any resets without paths update HEAD to the head being
403                  * switched to, saving the previous head in ORIG_HEAD before. */
404                 update_ref_status = reset_refs(rev, &oid);
405
406                 if (reset_type == HARD && !update_ref_status && !quiet)
407                         print_new_head_line(lookup_commit_reference(&oid));
408         }
409         if (!pathspec.nr)
410                 remove_branch_state();
411
412         return update_ref_status;
413 }