Merge branch 'js/blame-lib'
[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 "lockfile.h"
12 #include "tag.h"
13 #include "object.h"
14 #include "commit.h"
15 #include "run-command.h"
16 #include "refs.h"
17 #include "diff.h"
18 #include "diffcore.h"
19 #include "tree.h"
20 #include "branch.h"
21 #include "parse-options.h"
22 #include "unpack-trees.h"
23 #include "cache-tree.h"
24 #include "submodule.h"
25 #include "submodule-config.h"
26
27 static int recurse_submodules = RECURSE_SUBMODULES_DEFAULT;
28
29 static int option_parse_recurse_submodules(const struct option *opt,
30                                            const char *arg, int unset)
31 {
32         if (unset) {
33                 recurse_submodules = RECURSE_SUBMODULES_OFF;
34                 return 0;
35         }
36         if (arg)
37                 recurse_submodules =
38                         parse_update_recurse_submodules_arg(opt->long_name,
39                                                             arg);
40         else
41                 recurse_submodules = RECURSE_SUBMODULES_ON;
42
43         return 0;
44 }
45
46 static const char * const git_reset_usage[] = {
47         N_("git reset [--mixed | --soft | --hard | --merge | --keep] [-q] [<commit>]"),
48         N_("git reset [-q] [<tree-ish>] [--] <paths>..."),
49         N_("git reset --patch [<tree-ish>] [--] [<paths>...]"),
50         NULL
51 };
52
53 enum reset_type { MIXED, SOFT, HARD, MERGE, KEEP, NONE };
54 static const char *reset_type_names[] = {
55         N_("mixed"), N_("soft"), N_("hard"), N_("merge"), N_("keep"), NULL
56 };
57
58 static inline int is_merge(void)
59 {
60         return !access(git_path_merge_head(), F_OK);
61 }
62
63 static int reset_index(const struct object_id *oid, int reset_type, int quiet)
64 {
65         int nr = 1;
66         struct tree_desc desc[2];
67         struct tree *tree;
68         struct unpack_trees_options opts;
69
70         memset(&opts, 0, sizeof(opts));
71         opts.head_idx = 1;
72         opts.src_index = &the_index;
73         opts.dst_index = &the_index;
74         opts.fn = oneway_merge;
75         opts.merge = 1;
76         if (!quiet)
77                 opts.verbose_update = 1;
78         switch (reset_type) {
79         case KEEP:
80         case MERGE:
81                 opts.update = 1;
82                 break;
83         case HARD:
84                 opts.update = 1;
85                 /* fallthrough */
86         default:
87                 opts.reset = 1;
88         }
89
90         read_cache_unmerged();
91
92         if (reset_type == KEEP) {
93                 struct object_id head_oid;
94                 if (get_oid("HEAD", &head_oid))
95                         return error(_("You do not have a valid HEAD."));
96                 if (!fill_tree_descriptor(desc, head_oid.hash))
97                         return error(_("Failed to find tree of HEAD."));
98                 nr++;
99                 opts.fn = twoway_merge;
100         }
101
102         if (!fill_tree_descriptor(desc + nr - 1, oid->hash))
103                 return error(_("Failed to find tree of %s."), oid_to_hex(oid));
104         if (unpack_trees(nr, desc, &opts))
105                 return -1;
106
107         if (reset_type == MIXED || reset_type == HARD) {
108                 tree = parse_tree_indirect(oid);
109                 prime_cache_tree(&the_index, tree);
110         }
111
112         return 0;
113 }
114
115 static void print_new_head_line(struct commit *commit)
116 {
117         const char *hex, *body;
118         const char *msg;
119
120         hex = find_unique_abbrev(commit->object.oid.hash, DEFAULT_ABBREV);
121         printf(_("HEAD is now at %s"), hex);
122         msg = logmsg_reencode(commit, NULL, get_log_output_encoding());
123         body = strstr(msg, "\n\n");
124         if (body) {
125                 const char *eol;
126                 size_t len;
127                 body = skip_blank_lines(body + 2);
128                 eol = strchr(body, '\n');
129                 len = eol ? eol - body : strlen(body);
130                 printf(" %.*s\n", (int) len, body);
131         }
132         else
133                 printf("\n");
134         unuse_commit_buffer(commit, msg);
135 }
136
137 static void update_index_from_diff(struct diff_queue_struct *q,
138                 struct diff_options *opt, void *data)
139 {
140         int i;
141         int intent_to_add = *(int *)data;
142
143         for (i = 0; i < q->nr; i++) {
144                 struct diff_filespec *one = q->queue[i]->one;
145                 int is_missing = !(one->mode && !is_null_oid(&one->oid));
146                 struct cache_entry *ce;
147
148                 if (is_missing && !intent_to_add) {
149                         remove_file_from_cache(one->path);
150                         continue;
151                 }
152
153                 ce = make_cache_entry(one->mode, one->oid.hash, one->path,
154                                       0, 0);
155                 if (!ce)
156                         die(_("make_cache_entry failed for path '%s'"),
157                             one->path);
158                 if (is_missing) {
159                         ce->ce_flags |= CE_INTENT_TO_ADD;
160                         set_object_name_for_intent_to_add_entry(ce);
161                 }
162                 add_cache_entry(ce, ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE);
163         }
164 }
165
166 static int read_from_tree(const struct pathspec *pathspec,
167                           struct object_id *tree_oid,
168                           int intent_to_add)
169 {
170         struct diff_options opt;
171
172         memset(&opt, 0, sizeof(opt));
173         copy_pathspec(&opt.pathspec, pathspec);
174         opt.output_format = DIFF_FORMAT_CALLBACK;
175         opt.format_callback = update_index_from_diff;
176         opt.format_callback_data = &intent_to_add;
177
178         if (do_diff_cache(tree_oid, &opt))
179                 return 1;
180         diffcore_std(&opt);
181         diff_flush(&opt);
182         clear_pathspec(&opt.pathspec);
183
184         return 0;
185 }
186
187 static void set_reflog_message(struct strbuf *sb, const char *action,
188                                const char *rev)
189 {
190         const char *rla = getenv("GIT_REFLOG_ACTION");
191
192         strbuf_reset(sb);
193         if (rla)
194                 strbuf_addf(sb, "%s: %s", rla, action);
195         else if (rev)
196                 strbuf_addf(sb, "reset: moving to %s", rev);
197         else
198                 strbuf_addf(sb, "reset: %s", action);
199 }
200
201 static void die_if_unmerged_cache(int reset_type)
202 {
203         if (is_merge() || unmerged_cache())
204                 die(_("Cannot do a %s reset in the middle of a merge."),
205                     _(reset_type_names[reset_type]));
206
207 }
208
209 static void parse_args(struct pathspec *pathspec,
210                        const char **argv, const char *prefix,
211                        int patch_mode,
212                        const char **rev_ret)
213 {
214         const char *rev = "HEAD";
215         struct object_id unused;
216         /*
217          * Possible arguments are:
218          *
219          * git reset [-opts] [<rev>]
220          * git reset [-opts] <tree> [<paths>...]
221          * git reset [-opts] <tree> -- [<paths>...]
222          * git reset [-opts] -- [<paths>...]
223          * git reset [-opts] <paths>...
224          *
225          * At this point, argv points immediately after [-opts].
226          */
227
228         if (argv[0]) {
229                 if (!strcmp(argv[0], "--")) {
230                         argv++; /* reset to HEAD, possibly with paths */
231                 } else if (argv[1] && !strcmp(argv[1], "--")) {
232                         rev = argv[0];
233                         argv += 2;
234                 }
235                 /*
236                  * Otherwise, argv[0] could be either <rev> or <paths> and
237                  * has to be unambiguous. If there is a single argument, it
238                  * can not be a tree
239                  */
240                 else if ((!argv[1] && !get_sha1_committish(argv[0], unused.hash)) ||
241                          (argv[1] && !get_sha1_treeish(argv[0], unused.hash))) {
242                         /*
243                          * Ok, argv[0] looks like a commit/tree; it should not
244                          * be a filename.
245                          */
246                         verify_non_filename(prefix, argv[0]);
247                         rev = *argv++;
248                 } else {
249                         /* Otherwise we treat this as a filename */
250                         verify_filename(prefix, argv[0], 1);
251                 }
252         }
253         *rev_ret = rev;
254
255         if (read_cache() < 0)
256                 die(_("index file corrupt"));
257
258         parse_pathspec(pathspec, 0,
259                        PATHSPEC_PREFER_FULL |
260                        (patch_mode ? PATHSPEC_PREFIX_ORIGIN : 0),
261                        prefix, argv);
262 }
263
264 static int reset_refs(const char *rev, const struct object_id *oid)
265 {
266         int update_ref_status;
267         struct strbuf msg = STRBUF_INIT;
268         struct object_id *orig = NULL, oid_orig,
269                 *old_orig = NULL, oid_old_orig;
270
271         if (!get_oid("ORIG_HEAD", &oid_old_orig))
272                 old_orig = &oid_old_orig;
273         if (!get_oid("HEAD", &oid_orig)) {
274                 orig = &oid_orig;
275                 set_reflog_message(&msg, "updating ORIG_HEAD", NULL);
276                 update_ref_oid(msg.buf, "ORIG_HEAD", orig, old_orig, 0,
277                            UPDATE_REFS_MSG_ON_ERR);
278         } else if (old_orig)
279                 delete_ref(NULL, "ORIG_HEAD", old_orig->hash, 0);
280         set_reflog_message(&msg, "updating HEAD", rev);
281         update_ref_status = update_ref_oid(msg.buf, "HEAD", oid, orig, 0,
282                                        UPDATE_REFS_MSG_ON_ERR);
283         strbuf_release(&msg);
284         return update_ref_status;
285 }
286
287 int cmd_reset(int argc, const char **argv, const char *prefix)
288 {
289         int reset_type = NONE, update_ref_status = 0, quiet = 0;
290         int patch_mode = 0, unborn;
291         const char *rev;
292         struct object_id oid;
293         struct pathspec pathspec;
294         int intent_to_add = 0;
295         const struct option options[] = {
296                 OPT__QUIET(&quiet, N_("be quiet, only report errors")),
297                 OPT_SET_INT(0, "mixed", &reset_type,
298                                                 N_("reset HEAD and index"), MIXED),
299                 OPT_SET_INT(0, "soft", &reset_type, N_("reset only HEAD"), SOFT),
300                 OPT_SET_INT(0, "hard", &reset_type,
301                                 N_("reset HEAD, index and working tree"), HARD),
302                 OPT_SET_INT(0, "merge", &reset_type,
303                                 N_("reset HEAD, index and working tree"), MERGE),
304                 OPT_SET_INT(0, "keep", &reset_type,
305                                 N_("reset HEAD but keep local changes"), KEEP),
306                 { OPTION_CALLBACK, 0, "recurse-submodules", &recurse_submodules,
307                             "reset", "control recursive updating of submodules",
308                             PARSE_OPT_OPTARG, option_parse_recurse_submodules },
309                 OPT_BOOL('p', "patch", &patch_mode, N_("select hunks interactively")),
310                 OPT_BOOL('N', "intent-to-add", &intent_to_add,
311                                 N_("record only the fact that removed paths will be added later")),
312                 OPT_END()
313         };
314
315         git_config(git_default_config, NULL);
316
317         argc = parse_options(argc, argv, prefix, options, git_reset_usage,
318                                                 PARSE_OPT_KEEP_DASHDASH);
319         parse_args(&pathspec, argv, prefix, patch_mode, &rev);
320
321         if (recurse_submodules != RECURSE_SUBMODULES_DEFAULT) {
322                 gitmodules_config();
323                 git_config(submodule_config, NULL);
324                 set_config_update_recurse_submodules(RECURSE_SUBMODULES_ON);
325         }
326
327         unborn = !strcmp(rev, "HEAD") && get_sha1("HEAD", oid.hash);
328         if (unborn) {
329                 /* reset on unborn branch: treat as reset to empty tree */
330                 hashcpy(oid.hash, EMPTY_TREE_SHA1_BIN);
331         } else if (!pathspec.nr) {
332                 struct commit *commit;
333                 if (get_sha1_committish(rev, oid.hash))
334                         die(_("Failed to resolve '%s' as a valid revision."), rev);
335                 commit = lookup_commit_reference(&oid);
336                 if (!commit)
337                         die(_("Could not parse object '%s'."), rev);
338                 oidcpy(&oid, &commit->object.oid);
339         } else {
340                 struct tree *tree;
341                 if (get_sha1_treeish(rev, oid.hash))
342                         die(_("Failed to resolve '%s' as a valid tree."), rev);
343                 tree = parse_tree_indirect(&oid);
344                 if (!tree)
345                         die(_("Could not parse object '%s'."), rev);
346                 oidcpy(&oid, &tree->object.oid);
347         }
348
349         if (patch_mode) {
350                 if (reset_type != NONE)
351                         die(_("--patch is incompatible with --{hard,mixed,soft}"));
352                 return run_add_interactive(rev, "--patch=reset", &pathspec);
353         }
354
355         /* git reset tree [--] paths... can be used to
356          * load chosen paths from the tree into the index without
357          * affecting the working tree nor HEAD. */
358         if (pathspec.nr) {
359                 if (reset_type == MIXED)
360                         warning(_("--mixed with paths is deprecated; use 'git reset -- <paths>' instead."));
361                 else if (reset_type != NONE)
362                         die(_("Cannot do %s reset with paths."),
363                                         _(reset_type_names[reset_type]));
364         }
365         if (reset_type == NONE)
366                 reset_type = MIXED; /* by default */
367
368         if (reset_type != SOFT && (reset_type != MIXED || get_git_work_tree()))
369                 setup_work_tree();
370
371         if (reset_type == MIXED && is_bare_repository())
372                 die(_("%s reset is not allowed in a bare repository"),
373                     _(reset_type_names[reset_type]));
374
375         if (intent_to_add && reset_type != MIXED)
376                 die(_("-N can only be used with --mixed"));
377
378         /* Soft reset does not touch the index file nor the working tree
379          * at all, but requires them in a good order.  Other resets reset
380          * the index file to the tree object we are switching to. */
381         if (reset_type == SOFT || reset_type == KEEP)
382                 die_if_unmerged_cache(reset_type);
383
384         if (reset_type != SOFT) {
385                 struct lock_file *lock = xcalloc(1, sizeof(*lock));
386                 hold_locked_index(lock, LOCK_DIE_ON_ERROR);
387                 if (reset_type == MIXED) {
388                         int flags = quiet ? REFRESH_QUIET : REFRESH_IN_PORCELAIN;
389                         if (read_from_tree(&pathspec, &oid, intent_to_add))
390                                 return 1;
391                         if (get_git_work_tree())
392                                 refresh_index(&the_index, flags, NULL, NULL,
393                                               _("Unstaged changes after reset:"));
394                 } else {
395                         int err = reset_index(&oid, reset_type, quiet);
396                         if (reset_type == KEEP && !err)
397                                 err = reset_index(&oid, MIXED, quiet);
398                         if (err)
399                                 die(_("Could not reset index file to revision '%s'."), rev);
400                 }
401
402                 if (write_locked_index(&the_index, lock, COMMIT_LOCK))
403                         die(_("Could not write new index file."));
404         }
405
406         if (!pathspec.nr && !unborn) {
407                 /* Any resets without paths update HEAD to the head being
408                  * switched to, saving the previous head in ORIG_HEAD before. */
409                 update_ref_status = reset_refs(rev, &oid);
410
411                 if (reset_type == HARD && !update_ref_status && !quiet)
412                         print_new_head_line(lookup_commit_reference(&oid));
413         }
414         if (!pathspec.nr)
415                 remove_branch_state();
416
417         return update_ref_status;
418 }