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