branch: make create_branch accept a merge base rev
[git/git.git] / branch.c
1 #include "git-compat-util.h"
2 #include "cache.h"
3 #include "config.h"
4 #include "branch.h"
5 #include "refs.h"
6 #include "refspec.h"
7 #include "remote.h"
8 #include "commit.h"
9 #include "worktree.h"
10
11 struct tracking {
12 struct refspec_item spec;
13 char *src;
14 const char *remote;
15 int matches;
16 };
17
18 static int find_tracked_branch(struct remote *remote, void *priv)
19 {
20 struct tracking *tracking = priv;
21
22 if (!remote_find_tracking(remote, &tracking->spec)) {
23 if (++tracking->matches == 1) {
24 tracking->src = tracking->spec.src;
25 tracking->remote = remote->name;
26 } else {
27 free(tracking->spec.src);
28 FREE_AND_NULL(tracking->src);
29 }
30 tracking->spec.src = NULL;
31 }
32
33 return 0;
34 }
35
36 static int should_setup_rebase(const char *origin)
37 {
38 switch (autorebase) {
39 case AUTOREBASE_NEVER:
40 return 0;
41 case AUTOREBASE_LOCAL:
42 return origin == NULL;
43 case AUTOREBASE_REMOTE:
44 return origin != NULL;
45 case AUTOREBASE_ALWAYS:
46 return 1;
47 }
48 return 0;
49 }
50
51 static const char tracking_advice[] =
52 N_("\n"
53 "After fixing the error cause you may try to fix up\n"
54 "the remote tracking information by invoking\n"
55 "\"git branch --set-upstream-to=%s%s%s\".");
56
57 int install_branch_config(int flag, const char *local, const char *origin, const char *remote)
58 {
59 const char *shortname = NULL;
60 struct strbuf key = STRBUF_INIT;
61 int rebasing = should_setup_rebase(origin);
62
63 if (skip_prefix(remote, "refs/heads/", &shortname)
64 && !strcmp(local, shortname)
65 && !origin) {
66 warning(_("Not setting branch %s as its own upstream."),
67 local);
68 return 0;
69 }
70
71 strbuf_addf(&key, "branch.%s.remote", local);
72 if (git_config_set_gently(key.buf, origin ? origin : ".") < 0)
73 goto out_err;
74
75 strbuf_reset(&key);
76 strbuf_addf(&key, "branch.%s.merge", local);
77 if (git_config_set_gently(key.buf, remote) < 0)
78 goto out_err;
79
80 if (rebasing) {
81 strbuf_reset(&key);
82 strbuf_addf(&key, "branch.%s.rebase", local);
83 if (git_config_set_gently(key.buf, "true") < 0)
84 goto out_err;
85 }
86 strbuf_release(&key);
87
88 if (flag & BRANCH_CONFIG_VERBOSE) {
89 if (shortname) {
90 if (origin)
91 printf_ln(rebasing ?
92 _("Branch '%s' set up to track remote branch '%s' from '%s' by rebasing.") :
93 _("Branch '%s' set up to track remote branch '%s' from '%s'."),
94 local, shortname, origin);
95 else
96 printf_ln(rebasing ?
97 _("Branch '%s' set up to track local branch '%s' by rebasing.") :
98 _("Branch '%s' set up to track local branch '%s'."),
99 local, shortname);
100 } else {
101 if (origin)
102 printf_ln(rebasing ?
103 _("Branch '%s' set up to track remote ref '%s' by rebasing.") :
104 _("Branch '%s' set up to track remote ref '%s'."),
105 local, remote);
106 else
107 printf_ln(rebasing ?
108 _("Branch '%s' set up to track local ref '%s' by rebasing.") :
109 _("Branch '%s' set up to track local ref '%s'."),
110 local, remote);
111 }
112 }
113
114 return 0;
115
116 out_err:
117 strbuf_release(&key);
118 error(_("Unable to write upstream branch configuration"));
119
120 advise(_(tracking_advice),
121 origin ? origin : "",
122 origin ? "/" : "",
123 shortname ? shortname : remote);
124
125 return -1;
126 }
127
128 /*
129 * This is called when new_ref is branched off of orig_ref, and tries
130 * to infer the settings for branch.<new_ref>.{remote,merge} from the
131 * config.
132 */
133 static void setup_tracking(const char *new_ref, const char *orig_ref,
134 enum branch_track track, int quiet)
135 {
136 struct tracking tracking;
137 int config_flags = quiet ? 0 : BRANCH_CONFIG_VERBOSE;
138
139 memset(&tracking, 0, sizeof(tracking));
140 tracking.spec.dst = (char *)orig_ref;
141 if (for_each_remote(find_tracked_branch, &tracking))
142 return;
143
144 if (!tracking.matches)
145 switch (track) {
146 case BRANCH_TRACK_ALWAYS:
147 case BRANCH_TRACK_EXPLICIT:
148 case BRANCH_TRACK_OVERRIDE:
149 break;
150 default:
151 return;
152 }
153
154 if (tracking.matches > 1)
155 die(_("Not tracking: ambiguous information for ref %s"),
156 orig_ref);
157
158 if (install_branch_config(config_flags, new_ref, tracking.remote,
159 tracking.src ? tracking.src : orig_ref) < 0)
160 exit(-1);
161
162 free(tracking.src);
163 }
164
165 int read_branch_desc(struct strbuf *buf, const char *branch_name)
166 {
167 char *v = NULL;
168 struct strbuf name = STRBUF_INIT;
169 strbuf_addf(&name, "branch.%s.description", branch_name);
170 if (git_config_get_string(name.buf, &v)) {
171 strbuf_release(&name);
172 return -1;
173 }
174 strbuf_addstr(buf, v);
175 free(v);
176 strbuf_release(&name);
177 return 0;
178 }
179
180 /*
181 * Check if 'name' can be a valid name for a branch; die otherwise.
182 * Return 1 if the named branch already exists; return 0 otherwise.
183 * Fill ref with the full refname for the branch.
184 */
185 int validate_branchname(const char *name, struct strbuf *ref)
186 {
187 if (strbuf_check_branch_ref(ref, name))
188 die(_("'%s' is not a valid branch name."), name);
189
190 return ref_exists(ref->buf);
191 }
192
193 /*
194 * Check if a branch 'name' can be created as a new branch; die otherwise.
195 * 'force' can be used when it is OK for the named branch already exists.
196 * Return 1 if the named branch already exists; return 0 otherwise.
197 * Fill ref with the full refname for the branch.
198 */
199 int validate_new_branchname(const char *name, struct strbuf *ref, int force)
200 {
201 const char *head;
202
203 if (!validate_branchname(name, ref))
204 return 0;
205
206 if (!force)
207 die(_("A branch named '%s' already exists."),
208 ref->buf + strlen("refs/heads/"));
209
210 head = resolve_ref_unsafe("HEAD", 0, NULL, NULL);
211 if (!is_bare_repository() && head && !strcmp(head, ref->buf))
212 die(_("Cannot force update the current branch."));
213
214 return 1;
215 }
216
217 static int check_tracking_branch(struct remote *remote, void *cb_data)
218 {
219 char *tracking_branch = cb_data;
220 struct refspec_item query;
221 memset(&query, 0, sizeof(struct refspec_item));
222 query.dst = tracking_branch;
223 return !remote_find_tracking(remote, &query);
224 }
225
226 static int validate_remote_tracking_branch(char *ref)
227 {
228 return !for_each_remote(check_tracking_branch, ref);
229 }
230
231 static const char upstream_not_branch[] =
232 N_("Cannot setup tracking information; starting point '%s' is not a branch.");
233 static const char upstream_missing[] =
234 N_("the requested upstream branch '%s' does not exist");
235 static const char upstream_advice[] =
236 N_("\n"
237 "If you are planning on basing your work on an upstream\n"
238 "branch that already exists at the remote, you may need to\n"
239 "run \"git fetch\" to retrieve it.\n"
240 "\n"
241 "If you are planning to push out a new local branch that\n"
242 "will track its remote counterpart, you may want to use\n"
243 "\"git push -u\" to set the upstream config as you push.");
244
245 void create_branch(struct repository *r,
246 const char *name, const char *start_name,
247 int force, int clobber_head_ok, int reflog,
248 int quiet, enum branch_track track)
249 {
250 struct commit *commit;
251 struct object_id oid;
252 char *real_ref;
253 struct strbuf ref = STRBUF_INIT;
254 int forcing = 0;
255 int dont_change_ref = 0;
256 int explicit_tracking = 0;
257
258 if (track == BRANCH_TRACK_EXPLICIT || track == BRANCH_TRACK_OVERRIDE)
259 explicit_tracking = 1;
260
261 if ((track == BRANCH_TRACK_OVERRIDE || clobber_head_ok)
262 ? validate_branchname(name, &ref)
263 : validate_new_branchname(name, &ref, force)) {
264 if (!force)
265 dont_change_ref = 1;
266 else
267 forcing = 1;
268 }
269
270 real_ref = NULL;
271 if (get_oid_mb(start_name, &oid)) {
272 if (explicit_tracking) {
273 if (advice_set_upstream_failure) {
274 error(_(upstream_missing), start_name);
275 advise(_(upstream_advice));
276 exit(1);
277 }
278 die(_(upstream_missing), start_name);
279 }
280 die(_("Not a valid object name: '%s'."), start_name);
281 }
282
283 switch (dwim_ref(start_name, strlen(start_name), &oid, &real_ref)) {
284 case 0:
285 /* Not branching from any existing branch */
286 if (explicit_tracking)
287 die(_(upstream_not_branch), start_name);
288 break;
289 case 1:
290 /* Unique completion -- good, only if it is a real branch */
291 if (!starts_with(real_ref, "refs/heads/") &&
292 validate_remote_tracking_branch(real_ref)) {
293 if (explicit_tracking)
294 die(_(upstream_not_branch), start_name);
295 else
296 real_ref = NULL;
297 }
298 break;
299 default:
300 die(_("Ambiguous object name: '%s'."), start_name);
301 break;
302 }
303
304 if ((commit = lookup_commit_reference(r, &oid)) == NULL)
305 die(_("Not a valid branch point: '%s'."), start_name);
306 oidcpy(&oid, &commit->object.oid);
307
308 if (reflog)
309 log_all_ref_updates = LOG_REFS_NORMAL;
310
311 if (!dont_change_ref) {
312 struct ref_transaction *transaction;
313 struct strbuf err = STRBUF_INIT;
314 char *msg;
315
316 if (forcing)
317 msg = xstrfmt("branch: Reset to %s", start_name);
318 else
319 msg = xstrfmt("branch: Created from %s", start_name);
320
321 transaction = ref_transaction_begin(&err);
322 if (!transaction ||
323 ref_transaction_update(transaction, ref.buf,
324 &oid, forcing ? NULL : &null_oid,
325 0, msg, &err) ||
326 ref_transaction_commit(transaction, &err))
327 die("%s", err.buf);
328 ref_transaction_free(transaction);
329 strbuf_release(&err);
330 free(msg);
331 }
332
333 if (real_ref && track)
334 setup_tracking(ref.buf + 11, real_ref, track, quiet);
335
336 strbuf_release(&ref);
337 free(real_ref);
338 }
339
340 void remove_branch_state(struct repository *r)
341 {
342 unlink(git_path_cherry_pick_head(r));
343 unlink(git_path_revert_head(r));
344 unlink(git_path_merge_head(r));
345 unlink(git_path_merge_rr(r));
346 unlink(git_path_merge_msg(r));
347 unlink(git_path_merge_mode(r));
348 unlink(git_path_squash_msg(r));
349 }
350
351 void die_if_checked_out(const char *branch, int ignore_current_worktree)
352 {
353 const struct worktree *wt;
354
355 wt = find_shared_symref("HEAD", branch);
356 if (!wt || (ignore_current_worktree && wt->is_current))
357 return;
358 skip_prefix(branch, "refs/heads/", &branch);
359 die(_("'%s' is already checked out at '%s'"),
360 branch, wt->path);
361 }
362
363 int replace_each_worktree_head_symref(const char *oldref, const char *newref,
364 const char *logmsg)
365 {
366 int ret = 0;
367 struct worktree **worktrees = get_worktrees(0);
368 int i;
369
370 for (i = 0; worktrees[i]; i++) {
371 struct ref_store *refs;
372
373 if (worktrees[i]->is_detached)
374 continue;
375 if (!worktrees[i]->head_ref)
376 continue;
377 if (strcmp(oldref, worktrees[i]->head_ref))
378 continue;
379
380 refs = get_worktree_ref_store(worktrees[i]);
381 if (refs_create_symref(refs, "HEAD", newref, logmsg))
382 ret = error(_("HEAD of working tree %s is not updated"),
383 worktrees[i]->path);
384 }
385
386 free_worktrees(worktrees);
387 return ret;
388 }