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
27static 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
34enum reset_type { MIXED, SOFT, HARD, MERGE, KEEP, NONE };
35static const char *reset_type_names[] = {
36 N_("mixed"), N_("soft"), N_("hard"), N_("merge"), N_("keep"), NULL
37};
38
39static inline int is_merge(void)
40{
41 return !access(git_path_merge_head(), F_OK);
42}
43
44static 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
96static 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
118static 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
147static 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
168static 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
182static 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
190static 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
245static 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
268static 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
276int 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}