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