reset: add option "--keep" to "git reset"
[git/jnareb-git.git] / builtin-reset.c
blobda61f20e87655583ffb995989cefb19b577e8da6
1 /*
2 * "git reset" builtin command
4 * Copyright (c) 2007 Carlos Rica
6 * Based on git-reset.sh, which is
8 * Copyright (c) 2005, 2006 Linus Torvalds and Junio C Hamano
9 */
10 #include "cache.h"
11 #include "tag.h"
12 #include "object.h"
13 #include "commit.h"
14 #include "run-command.h"
15 #include "refs.h"
16 #include "diff.h"
17 #include "diffcore.h"
18 #include "tree.h"
19 #include "branch.h"
20 #include "parse-options.h"
21 #include "unpack-trees.h"
22 #include "cache-tree.h"
24 static const char * const git_reset_usage[] = {
25 "git reset [--mixed | --soft | --hard | --merge | --keep] [-q] [<commit>]",
26 "git reset [--mixed] <commit> [--] <paths>...",
27 NULL
30 enum reset_type { MIXED, SOFT, HARD, MERGE, KEEP, NONE };
31 static const char *reset_type_names[] = {
32 "mixed", "soft", "hard", "merge", "keep", NULL
35 static char *args_to_str(const char **argv)
37 char *buf = NULL;
38 unsigned long len, space = 0, nr = 0;
40 for (; *argv; argv++) {
41 len = strlen(*argv);
42 ALLOC_GROW(buf, nr + 1 + len, space);
43 if (nr)
44 buf[nr++] = ' ';
45 memcpy(buf + nr, *argv, len);
46 nr += len;
48 ALLOC_GROW(buf, nr + 1, space);
49 buf[nr] = '\0';
51 return buf;
54 static inline int is_merge(void)
56 return !access(git_path("MERGE_HEAD"), F_OK);
59 static int reset_index_file(const unsigned char *sha1, int reset_type, int quiet)
61 int nr = 1;
62 int newfd;
63 struct tree_desc desc[2];
64 struct unpack_trees_options opts;
65 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
67 memset(&opts, 0, sizeof(opts));
68 opts.head_idx = 1;
69 opts.src_index = &the_index;
70 opts.dst_index = &the_index;
71 opts.fn = oneway_merge;
72 opts.merge = 1;
73 if (!quiet)
74 opts.verbose_update = 1;
75 switch (reset_type) {
76 case KEEP:
77 case MERGE:
78 opts.update = 1;
79 break;
80 case HARD:
81 opts.update = 1;
82 /* fallthrough */
83 default:
84 opts.reset = 1;
87 newfd = hold_locked_index(lock, 1);
89 read_cache_unmerged();
91 if (reset_type == KEEP) {
92 unsigned char head_sha1[20];
93 if (get_sha1("HEAD", head_sha1))
94 return error("You do not have a valid HEAD.");
95 if (!fill_tree_descriptor(desc, head_sha1))
96 return error("Failed to find tree of HEAD.");
97 nr++;
98 opts.fn = twoway_merge;
101 if (!fill_tree_descriptor(desc + nr - 1, sha1))
102 return error("Failed to find tree of %s.", sha1_to_hex(sha1));
103 if (unpack_trees(nr, desc, &opts))
104 return -1;
105 if (write_cache(newfd, active_cache, active_nr) ||
106 commit_locked_index(lock))
107 return error("Could not write new index file.");
109 return 0;
112 static void print_new_head_line(struct commit *commit)
114 const char *hex, *body;
116 hex = find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV);
117 printf("HEAD is now at %s", hex);
118 body = strstr(commit->buffer, "\n\n");
119 if (body) {
120 const char *eol;
121 size_t len;
122 body += 2;
123 eol = strchr(body, '\n');
124 len = eol ? eol - body : strlen(body);
125 printf(" %.*s\n", (int) len, body);
127 else
128 printf("\n");
131 static int update_index_refresh(int fd, struct lock_file *index_lock, int flags)
133 int result;
135 if (!index_lock) {
136 index_lock = xcalloc(1, sizeof(struct lock_file));
137 fd = hold_locked_index(index_lock, 1);
140 if (read_cache() < 0)
141 return error("Could not read index");
143 result = refresh_index(&the_index, (flags), NULL, NULL,
144 "Unstaged changes after reset:") ? 1 : 0;
145 if (write_cache(fd, active_cache, active_nr) ||
146 commit_locked_index(index_lock))
147 return error ("Could not refresh index");
148 return result;
151 static void update_index_from_diff(struct diff_queue_struct *q,
152 struct diff_options *opt, void *data)
154 int i;
155 int *discard_flag = data;
157 /* do_diff_cache() mangled the index */
158 discard_cache();
159 *discard_flag = 1;
160 read_cache();
162 for (i = 0; i < q->nr; i++) {
163 struct diff_filespec *one = q->queue[i]->one;
164 if (one->mode) {
165 struct cache_entry *ce;
166 ce = make_cache_entry(one->mode, one->sha1, one->path,
167 0, 0);
168 if (!ce)
169 die("make_cache_entry failed for path '%s'",
170 one->path);
171 add_cache_entry(ce, ADD_CACHE_OK_TO_ADD |
172 ADD_CACHE_OK_TO_REPLACE);
173 } else
174 remove_file_from_cache(one->path);
178 static int interactive_reset(const char *revision, const char **argv,
179 const char *prefix)
181 const char **pathspec = NULL;
183 if (*argv)
184 pathspec = get_pathspec(prefix, argv);
186 return run_add_interactive(revision, "--patch=reset", pathspec);
189 static int read_from_tree(const char *prefix, const char **argv,
190 unsigned char *tree_sha1, int refresh_flags)
192 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
193 int index_fd, index_was_discarded = 0;
194 struct diff_options opt;
196 memset(&opt, 0, sizeof(opt));
197 diff_tree_setup_paths(get_pathspec(prefix, (const char **)argv), &opt);
198 opt.output_format = DIFF_FORMAT_CALLBACK;
199 opt.format_callback = update_index_from_diff;
200 opt.format_callback_data = &index_was_discarded;
202 index_fd = hold_locked_index(lock, 1);
203 index_was_discarded = 0;
204 read_cache();
205 if (do_diff_cache(tree_sha1, &opt))
206 return 1;
207 diffcore_std(&opt);
208 diff_flush(&opt);
209 diff_tree_release_paths(&opt);
211 if (!index_was_discarded)
212 /* The index is still clobbered from do_diff_cache() */
213 discard_cache();
214 return update_index_refresh(index_fd, lock, refresh_flags);
217 static void prepend_reflog_action(const char *action, char *buf, size_t size)
219 const char *sep = ": ";
220 const char *rla = getenv("GIT_REFLOG_ACTION");
221 if (!rla)
222 rla = sep = "";
223 if (snprintf(buf, size, "%s%s%s", rla, sep, action) >= size)
224 warning("Reflog action message too long: %.*s...", 50, buf);
227 int cmd_reset(int argc, const char **argv, const char *prefix)
229 int i = 0, reset_type = NONE, update_ref_status = 0, quiet = 0;
230 int patch_mode = 0;
231 const char *rev = "HEAD";
232 unsigned char sha1[20], *orig = NULL, sha1_orig[20],
233 *old_orig = NULL, sha1_old_orig[20];
234 struct commit *commit;
235 char *reflog_action, msg[1024];
236 const struct option options[] = {
237 OPT__QUIET(&quiet),
238 OPT_SET_INT(0, "mixed", &reset_type,
239 "reset HEAD and index", MIXED),
240 OPT_SET_INT(0, "soft", &reset_type, "reset only HEAD", SOFT),
241 OPT_SET_INT(0, "hard", &reset_type,
242 "reset HEAD, index and working tree", HARD),
243 OPT_SET_INT(0, "merge", &reset_type,
244 "reset HEAD, index and working tree", MERGE),
245 OPT_SET_INT(0, "keep", &reset_type,
246 "reset HEAD but keep local changes", KEEP),
247 OPT_BOOLEAN('p', "patch", &patch_mode, "select hunks interactively"),
248 OPT_END()
251 git_config(git_default_config, NULL);
253 argc = parse_options(argc, argv, prefix, options, git_reset_usage,
254 PARSE_OPT_KEEP_DASHDASH);
255 reflog_action = args_to_str(argv);
256 setenv("GIT_REFLOG_ACTION", reflog_action, 0);
259 * Possible arguments are:
261 * git reset [-opts] <rev> <paths>...
262 * git reset [-opts] <rev> -- <paths>...
263 * git reset [-opts] -- <paths>...
264 * git reset [-opts] <paths>...
266 * At this point, argv[i] points immediately after [-opts].
269 if (i < argc) {
270 if (!strcmp(argv[i], "--")) {
271 i++; /* reset to HEAD, possibly with paths */
272 } else if (i + 1 < argc && !strcmp(argv[i+1], "--")) {
273 rev = argv[i];
274 i += 2;
277 * Otherwise, argv[i] could be either <rev> or <paths> and
278 * has to be unambiguous.
280 else if (!get_sha1(argv[i], sha1)) {
282 * Ok, argv[i] looks like a rev; it should not
283 * be a filename.
285 verify_non_filename(prefix, argv[i]);
286 rev = argv[i++];
287 } else {
288 /* Otherwise we treat this as a filename */
289 verify_filename(prefix, argv[i]);
293 if (get_sha1(rev, sha1))
294 die("Failed to resolve '%s' as a valid ref.", rev);
296 commit = lookup_commit_reference(sha1);
297 if (!commit)
298 die("Could not parse object '%s'.", rev);
299 hashcpy(sha1, commit->object.sha1);
301 if (patch_mode) {
302 if (reset_type != NONE)
303 die("--patch is incompatible with --{hard,mixed,soft}");
304 return interactive_reset(rev, argv + i, prefix);
307 /* git reset tree [--] paths... can be used to
308 * load chosen paths from the tree into the index without
309 * affecting the working tree nor HEAD. */
310 if (i < argc) {
311 if (reset_type == MIXED)
312 warning("--mixed option is deprecated with paths.");
313 else if (reset_type != NONE)
314 die("Cannot do %s reset with paths.",
315 reset_type_names[reset_type]);
316 return read_from_tree(prefix, argv + i, sha1,
317 quiet ? REFRESH_QUIET : REFRESH_IN_PORCELAIN);
319 if (reset_type == NONE)
320 reset_type = MIXED; /* by default */
322 if (reset_type == HARD || reset_type == MERGE)
323 setup_work_tree();
325 if (reset_type == MIXED && is_bare_repository())
326 die("%s reset is not allowed in a bare repository",
327 reset_type_names[reset_type]);
329 /* Soft reset does not touch the index file nor the working tree
330 * at all, but requires them in a good order. Other resets reset
331 * the index file to the tree object we are switching to. */
332 if (reset_type == SOFT) {
333 if (is_merge() || read_cache() < 0 || unmerged_cache())
334 die("Cannot do a soft reset in the middle of a merge.");
335 } else {
336 int err = reset_index_file(sha1, reset_type, quiet);
337 if (reset_type == KEEP)
338 err = err || reset_index_file(sha1, MIXED, quiet);
339 if (err)
340 die("Could not reset index file to revision '%s'.", rev);
343 /* Any resets update HEAD to the head being switched to,
344 * saving the previous head in ORIG_HEAD before. */
345 if (!get_sha1("ORIG_HEAD", sha1_old_orig))
346 old_orig = sha1_old_orig;
347 if (!get_sha1("HEAD", sha1_orig)) {
348 orig = sha1_orig;
349 prepend_reflog_action("updating ORIG_HEAD", msg, sizeof(msg));
350 update_ref(msg, "ORIG_HEAD", orig, old_orig, 0, MSG_ON_ERR);
352 else if (old_orig)
353 delete_ref("ORIG_HEAD", old_orig, 0);
354 prepend_reflog_action("updating HEAD", msg, sizeof(msg));
355 update_ref_status = update_ref(msg, "HEAD", sha1, orig, 0, MSG_ON_ERR);
357 switch (reset_type) {
358 case HARD:
359 if (!update_ref_status && !quiet)
360 print_new_head_line(commit);
361 break;
362 case SOFT: /* Nothing else to do. */
363 break;
364 case MIXED: /* Report what has not been updated. */
365 update_index_refresh(0, NULL,
366 quiet ? REFRESH_QUIET : REFRESH_IN_PORCELAIN);
367 break;
370 remove_branch_state();
372 free(reflog_action);
374 return update_ref_status;