Make fread/fwrite-like functions in http.c more like fread/fwrite.
[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(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 }