config: handle lack of newline at end of file better
[git/git.git] / builtin-reset.c
CommitLineData
0e5a7faa
CR
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 "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
20static const char builtin_reset_usage[] =
521b53e5 21"git-reset [--mixed | --soft | --hard] [-q] [<commit-ish>] [ [--] <paths>...]";
0e5a7faa
CR
22
23static char *args_to_str(const char **argv)
24{
25 char *buf = NULL;
26 unsigned long len, space = 0, nr = 0;
27
28 for (; *argv; argv++) {
29 len = strlen(*argv);
30 ALLOC_GROW(buf, nr + 1 + len, space);
31 if (nr)
32 buf[nr++] = ' ';
33 memcpy(buf + nr, *argv, len);
34 nr += len;
35 }
36 ALLOC_GROW(buf, nr + 1, space);
37 buf[nr] = '\0';
38
39 return buf;
40}
41
42static inline int is_merge(void)
43{
44 return !access(git_path("MERGE_HEAD"), F_OK);
45}
46
47static int unmerged_files(void)
48{
cdf4a751
JS
49 int i;
50 read_cache();
51 for (i = 0; i < active_nr; i++) {
52 struct cache_entry *ce = active_cache[i];
53 if (ce_stage(ce))
54 return 1;
55 }
56 return 0;
0e5a7faa
CR
57}
58
59static int reset_index_file(const unsigned char *sha1, int is_hard_reset)
60{
61 int i = 0;
62 const char *args[6];
63
64 args[i++] = "read-tree";
65 args[i++] = "-v";
66 args[i++] = "--reset";
67 if (is_hard_reset)
68 args[i++] = "-u";
69 args[i++] = sha1_to_hex(sha1);
70 args[i] = NULL;
71
72 return run_command_v_opt(args, RUN_GIT_CMD);
73}
74
75static void print_new_head_line(struct commit *commit)
76{
77 const char *hex, *dots = "...", *body;
78
79 hex = find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV);
80 if (!hex) {
81 hex = sha1_to_hex(commit->object.sha1);
82 dots = "";
83 }
84 printf("HEAD is now at %s%s", hex, dots);
85 body = strstr(commit->buffer, "\n\n");
86 if (body) {
87 const char *eol;
88 size_t len;
89 body += 2;
90 eol = strchr(body, '\n');
91 len = eol ? eol - body : strlen(body);
92 printf(" %.*s\n", (int) len, body);
93 }
94 else
95 printf("\n");
96}
97
620a6cd4 98static int update_index_refresh(int fd, struct lock_file *index_lock)
0e5a7faa 99{
620a6cd4 100 int result;
0e5a7faa 101
620a6cd4
JS
102 if (!index_lock) {
103 index_lock = xcalloc(1, sizeof(struct lock_file));
104 fd = hold_locked_index(index_lock, 1);
105 }
0e5a7faa 106
620a6cd4
JS
107 if (read_cache() < 0)
108 return error("Could not read index");
109 result = refresh_cache(0) ? 1 : 0;
110 if (write_cache(fd, active_cache, active_nr) ||
111 close(fd) ||
112 commit_locked_index(index_lock))
113 return error ("Could not refresh index");
114 return result;
115}
2e7a9785 116
0e5a7faa
CR
117static void update_index_from_diff(struct diff_queue_struct *q,
118 struct diff_options *opt, void *data)
119{
120 int i;
620a6cd4 121 int *discard_flag = data;
0e5a7faa
CR
122
123 /* do_diff_cache() mangled the index */
124 discard_cache();
620a6cd4 125 *discard_flag = 1;
0e5a7faa
CR
126 read_cache();
127
128 for (i = 0; i < q->nr; i++) {
129 struct diff_filespec *one = q->queue[i]->one;
130 if (one->mode) {
131 struct cache_entry *ce;
132 ce = make_cache_entry(one->mode, one->sha1, one->path,
133 0, 0);
134 add_cache_entry(ce, ADD_CACHE_OK_TO_ADD |
135 ADD_CACHE_OK_TO_REPLACE);
136 } else
137 remove_file_from_cache(one->path);
138 }
139}
140
141static int read_from_tree(const char *prefix, const char **argv,
142 unsigned char *tree_sha1)
143{
620a6cd4
JS
144 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
145 int index_fd, index_was_discarded = 0;
0e5a7faa
CR
146 struct diff_options opt;
147
148 memset(&opt, 0, sizeof(opt));
149 diff_tree_setup_paths(get_pathspec(prefix, (const char **)argv), &opt);
150 opt.output_format = DIFF_FORMAT_CALLBACK;
151 opt.format_callback = update_index_from_diff;
620a6cd4 152 opt.format_callback_data = &index_was_discarded;
0e5a7faa 153
620a6cd4
JS
154 index_fd = hold_locked_index(lock, 1);
155 index_was_discarded = 0;
0e5a7faa
CR
156 read_cache();
157 if (do_diff_cache(tree_sha1, &opt))
158 return 1;
159 diffcore_std(&opt);
160 diff_flush(&opt);
03b69c76 161 diff_tree_release_paths(&opt);
2e7a9785 162
620a6cd4
JS
163 if (!index_was_discarded)
164 /* The index is still clobbered from do_diff_cache() */
165 discard_cache();
166 return update_index_refresh(index_fd, lock);
0e5a7faa
CR
167}
168
169static void prepend_reflog_action(const char *action, char *buf, size_t size)
170{
171 const char *sep = ": ";
172 const char *rla = getenv("GIT_REFLOG_ACTION");
173 if (!rla)
174 rla = sep = "";
175 if (snprintf(buf, size, "%s%s%s", rla, sep, action) >= size)
176 warning("Reflog action message too long: %.*s...", 50, buf);
177}
178
179enum reset_type { MIXED, SOFT, HARD, NONE };
538dfe73 180static const char *reset_type_names[] = { "mixed", "soft", "hard", NULL };
0e5a7faa
CR
181
182int cmd_reset(int argc, const char **argv, const char *prefix)
183{
521b53e5 184 int i = 1, reset_type = NONE, update_ref_status = 0, quiet = 0;
0e5a7faa
CR
185 const char *rev = "HEAD";
186 unsigned char sha1[20], *orig = NULL, sha1_orig[20],
187 *old_orig = NULL, sha1_old_orig[20];
188 struct commit *commit;
189 char *reflog_action, msg[1024];
190
191 git_config(git_default_config);
192
193 reflog_action = args_to_str(argv);
194 setenv("GIT_REFLOG_ACTION", reflog_action, 0);
195
521b53e5 196 while (i < argc) {
0e5a7faa
CR
197 if (!strcmp(argv[i], "--mixed")) {
198 reset_type = MIXED;
199 i++;
200 }
201 else if (!strcmp(argv[i], "--soft")) {
202 reset_type = SOFT;
203 i++;
204 }
205 else if (!strcmp(argv[i], "--hard")) {
206 reset_type = HARD;
207 i++;
208 }
521b53e5
GP
209 else if (!strcmp(argv[i], "-q")) {
210 quiet = 1;
211 i++;
212 }
213 else
214 break;
0e5a7faa
CR
215 }
216
217 if (i < argc && argv[i][0] != '-')
218 rev = argv[i++];
219
220 if (get_sha1(rev, sha1))
221 die("Failed to resolve '%s' as a valid ref.", rev);
222
223 commit = lookup_commit_reference(sha1);
224 if (!commit)
225 die("Could not parse object '%s'.", rev);
226 hashcpy(sha1, commit->object.sha1);
227
228 if (i < argc && !strcmp(argv[i], "--"))
229 i++;
230 else if (i < argc && argv[i][0] == '-')
231 usage(builtin_reset_usage);
232
233 /* git reset tree [--] paths... can be used to
234 * load chosen paths from the tree into the index without
235 * affecting the working tree nor HEAD. */
236 if (i < argc) {
237 if (reset_type == MIXED)
238 warning("--mixed option is deprecated with paths.");
239 else if (reset_type != NONE)
240 die("Cannot do %s reset with paths.",
241 reset_type_names[reset_type]);
620a6cd4 242 return read_from_tree(prefix, argv + i, sha1);
0e5a7faa
CR
243 }
244 if (reset_type == NONE)
245 reset_type = MIXED; /* by default */
246
247 /* Soft reset does not touch the index file nor the working tree
248 * at all, but requires them in a good order. Other resets reset
249 * the index file to the tree object we are switching to. */
250 if (reset_type == SOFT) {
251 if (is_merge() || unmerged_files())
252 die("Cannot do a soft reset in the middle of a merge.");
253 }
254 else if (reset_index_file(sha1, (reset_type == HARD)))
255 die("Could not reset index file to revision '%s'.", rev);
256
257 /* Any resets update HEAD to the head being switched to,
258 * saving the previous head in ORIG_HEAD before. */
259 if (!get_sha1("ORIG_HEAD", sha1_old_orig))
260 old_orig = sha1_old_orig;
261 if (!get_sha1("HEAD", sha1_orig)) {
262 orig = sha1_orig;
263 prepend_reflog_action("updating ORIG_HEAD", msg, sizeof(msg));
264 update_ref(msg, "ORIG_HEAD", orig, old_orig, 0, MSG_ON_ERR);
265 }
266 else if (old_orig)
267 delete_ref("ORIG_HEAD", old_orig);
268 prepend_reflog_action("updating HEAD", msg, sizeof(msg));
269 update_ref_status = update_ref(msg, "HEAD", sha1, orig, 0, MSG_ON_ERR);
270
271 switch (reset_type) {
272 case HARD:
521b53e5 273 if (!update_ref_status && !quiet)
0e5a7faa
CR
274 print_new_head_line(commit);
275 break;
276 case SOFT: /* Nothing else to do. */
277 break;
278 case MIXED: /* Report what has not been updated. */
620a6cd4 279 update_index_refresh(0, NULL);
0e5a7faa
CR
280 break;
281 }
282
283 unlink(git_path("MERGE_HEAD"));
284 unlink(git_path("rr-cache/MERGE_RR"));
285 unlink(git_path("MERGE_MSG"));
286 unlink(git_path("SQUASH_MSG"));
287
288 free(reflog_action);
289
290 return update_ref_status;
291}