git-p4: chdir now properly sets PWD environment variable in msysGit
[git/git-p4.git] / builtin-reset.c
blobc24c21909194014b467c86fd3598796e7db576b3
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"
22 static const char * const git_reset_usage[] = {
23 "git reset [--mixed | --soft | --hard] [-q] [<commit>]",
24 "git reset [--mixed] <commit> [--] <paths>...",
25 NULL
28 static char *args_to_str(const char **argv)
30 char *buf = NULL;
31 unsigned long len, space = 0, nr = 0;
33 for (; *argv; argv++) {
34 len = strlen(*argv);
35 ALLOC_GROW(buf, nr + 1 + len, space);
36 if (nr)
37 buf[nr++] = ' ';
38 memcpy(buf + nr, *argv, len);
39 nr += len;
41 ALLOC_GROW(buf, nr + 1, space);
42 buf[nr] = '\0';
44 return buf;
47 static inline int is_merge(void)
49 return !access(git_path("MERGE_HEAD"), F_OK);
52 static int reset_index_file(const unsigned char *sha1, int is_hard_reset, int quiet)
54 int i = 0;
55 const char *args[6];
57 args[i++] = "read-tree";
58 if (!quiet)
59 args[i++] = "-v";
60 args[i++] = "--reset";
61 if (is_hard_reset)
62 args[i++] = "-u";
63 args[i++] = sha1_to_hex(sha1);
64 args[i] = NULL;
66 return run_command_v_opt(args, RUN_GIT_CMD);
69 static void print_new_head_line(struct commit *commit)
71 const char *hex, *body;
73 hex = find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV);
74 printf("HEAD is now at %s", hex);
75 body = strstr(commit->buffer, "\n\n");
76 if (body) {
77 const char *eol;
78 size_t len;
79 body += 2;
80 eol = strchr(body, '\n');
81 len = eol ? eol - body : strlen(body);
82 printf(" %.*s\n", (int) len, body);
84 else
85 printf("\n");
88 static int update_index_refresh(int fd, struct lock_file *index_lock, int flags)
90 int result;
92 if (!index_lock) {
93 index_lock = xcalloc(1, sizeof(struct lock_file));
94 fd = hold_locked_index(index_lock, 1);
97 if (read_cache() < 0)
98 return error("Could not read index");
100 result = refresh_cache(flags) ? 1 : 0;
101 if (write_cache(fd, active_cache, active_nr) ||
102 commit_locked_index(index_lock))
103 return error ("Could not refresh index");
104 return result;
107 static void update_index_from_diff(struct diff_queue_struct *q,
108 struct diff_options *opt, void *data)
110 int i;
111 int *discard_flag = data;
113 /* do_diff_cache() mangled the index */
114 discard_cache();
115 *discard_flag = 1;
116 read_cache();
118 for (i = 0; i < q->nr; i++) {
119 struct diff_filespec *one = q->queue[i]->one;
120 if (one->mode) {
121 struct cache_entry *ce;
122 ce = make_cache_entry(one->mode, one->sha1, one->path,
123 0, 0);
124 add_cache_entry(ce, ADD_CACHE_OK_TO_ADD |
125 ADD_CACHE_OK_TO_REPLACE);
126 } else
127 remove_file_from_cache(one->path);
131 static int read_from_tree(const char *prefix, const char **argv,
132 unsigned char *tree_sha1, int refresh_flags)
134 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
135 int index_fd, index_was_discarded = 0;
136 struct diff_options opt;
138 memset(&opt, 0, sizeof(opt));
139 diff_tree_setup_paths(get_pathspec(prefix, (const char **)argv), &opt);
140 opt.output_format = DIFF_FORMAT_CALLBACK;
141 opt.format_callback = update_index_from_diff;
142 opt.format_callback_data = &index_was_discarded;
144 index_fd = hold_locked_index(lock, 1);
145 index_was_discarded = 0;
146 read_cache();
147 if (do_diff_cache(tree_sha1, &opt))
148 return 1;
149 diffcore_std(&opt);
150 diff_flush(&opt);
151 diff_tree_release_paths(&opt);
153 if (!index_was_discarded)
154 /* The index is still clobbered from do_diff_cache() */
155 discard_cache();
156 return update_index_refresh(index_fd, lock, refresh_flags);
159 static void prepend_reflog_action(const char *action, char *buf, size_t size)
161 const char *sep = ": ";
162 const char *rla = getenv("GIT_REFLOG_ACTION");
163 if (!rla)
164 rla = sep = "";
165 if (snprintf(buf, size, "%s%s%s", rla, sep, action) >= size)
166 warning("Reflog action message too long: %.*s...", 50, buf);
169 enum reset_type { MIXED, SOFT, HARD, NONE };
170 static const char *reset_type_names[] = { "mixed", "soft", "hard", NULL };
172 int cmd_reset(int argc, const char **argv, const char *prefix)
174 int i = 0, reset_type = NONE, update_ref_status = 0, quiet = 0;
175 const char *rev = "HEAD";
176 unsigned char sha1[20], *orig = NULL, sha1_orig[20],
177 *old_orig = NULL, sha1_old_orig[20];
178 struct commit *commit;
179 char *reflog_action, msg[1024];
180 const struct option options[] = {
181 OPT_SET_INT(0, "mixed", &reset_type,
182 "reset HEAD and index", MIXED),
183 OPT_SET_INT(0, "soft", &reset_type, "reset only HEAD", SOFT),
184 OPT_SET_INT(0, "hard", &reset_type,
185 "reset HEAD, index and working tree", HARD),
186 OPT_BOOLEAN('q', NULL, &quiet,
187 "disable showing new HEAD in hard reset and progress message"),
188 OPT_END()
191 git_config(git_default_config, NULL);
193 argc = parse_options(argc, argv, options, git_reset_usage,
194 PARSE_OPT_KEEP_DASHDASH);
195 reflog_action = args_to_str(argv);
196 setenv("GIT_REFLOG_ACTION", reflog_action, 0);
199 * Possible arguments are:
201 * git reset [-opts] <rev> <paths>...
202 * git reset [-opts] <rev> -- <paths>...
203 * git reset [-opts] -- <paths>...
204 * git reset [-opts] <paths>...
206 * At this point, argv[i] points immediately after [-opts].
209 if (i < argc) {
210 if (!strcmp(argv[i], "--")) {
211 i++; /* reset to HEAD, possibly with paths */
212 } else if (i + 1 < argc && !strcmp(argv[i+1], "--")) {
213 rev = argv[i];
214 i += 2;
217 * Otherwise, argv[i] could be either <rev> or <paths> and
218 * has to be unambigous.
220 else if (!get_sha1(argv[i], sha1)) {
222 * Ok, argv[i] looks like a rev; it should not
223 * be a filename.
225 verify_non_filename(prefix, argv[i]);
226 rev = argv[i++];
227 } else {
228 /* Otherwise we treat this as a filename */
229 verify_filename(prefix, argv[i]);
233 if (get_sha1(rev, sha1))
234 die("Failed to resolve '%s' as a valid ref.", rev);
236 commit = lookup_commit_reference(sha1);
237 if (!commit)
238 die("Could not parse object '%s'.", rev);
239 hashcpy(sha1, commit->object.sha1);
241 /* git reset tree [--] paths... can be used to
242 * load chosen paths from the tree into the index without
243 * affecting the working tree nor HEAD. */
244 if (i < argc) {
245 if (reset_type == MIXED)
246 warning("--mixed option is deprecated with paths.");
247 else if (reset_type != NONE)
248 die("Cannot do %s reset with paths.",
249 reset_type_names[reset_type]);
250 return read_from_tree(prefix, argv + i, sha1,
251 quiet ? REFRESH_QUIET : REFRESH_SAY_CHANGED);
253 if (reset_type == NONE)
254 reset_type = MIXED; /* by default */
256 if (reset_type == HARD && is_bare_repository())
257 die("hard reset makes no sense in a bare repository");
259 /* Soft reset does not touch the index file nor the working tree
260 * at all, but requires them in a good order. Other resets reset
261 * the index file to the tree object we are switching to. */
262 if (reset_type == SOFT) {
263 if (is_merge() || read_cache() < 0 || unmerged_cache())
264 die("Cannot do a soft reset in the middle of a merge.");
266 else if (reset_index_file(sha1, (reset_type == HARD), quiet))
267 die("Could not reset index file to revision '%s'.", rev);
269 /* Any resets update HEAD to the head being switched to,
270 * saving the previous head in ORIG_HEAD before. */
271 if (!get_sha1("ORIG_HEAD", sha1_old_orig))
272 old_orig = sha1_old_orig;
273 if (!get_sha1("HEAD", sha1_orig)) {
274 orig = sha1_orig;
275 prepend_reflog_action("updating ORIG_HEAD", msg, sizeof(msg));
276 update_ref(msg, "ORIG_HEAD", orig, old_orig, 0, MSG_ON_ERR);
278 else if (old_orig)
279 delete_ref("ORIG_HEAD", old_orig);
280 prepend_reflog_action("updating HEAD", msg, sizeof(msg));
281 update_ref_status = update_ref(msg, "HEAD", sha1, orig, 0, MSG_ON_ERR);
283 switch (reset_type) {
284 case HARD:
285 if (!update_ref_status && !quiet)
286 print_new_head_line(commit);
287 break;
288 case SOFT: /* Nothing else to do. */
289 break;
290 case MIXED: /* Report what has not been updated. */
291 update_index_refresh(0, NULL,
292 quiet ? REFRESH_QUIET : REFRESH_SAY_CHANGED);
293 break;
296 remove_branch_state();
298 free(reflog_action);
300 return update_ref_status;