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 "sequencer.h"
   9 #include "commit.h"
  10 #include "worktree.h"
  11
  12 struct tracking {
  13         struct refspec_item spec;
  14         struct string_list *srcs;
  15         const char *remote;
  16         int matches;
  17 };
  18
  19 static int find_tracked_branch(struct remote *remote, void *priv)
  20 {
  21         struct tracking *tracking = priv;
  22
  23         if (!remote_find_tracking(remote, &tracking->spec)) {
  24                 if (++tracking->matches == 1) {
  25                         string_list_append(tracking->srcs, tracking->spec.src);
  26                         tracking->remote = remote->name;
  27                 } else {
  28                         free(tracking->spec.src);
  29                         string_list_clear(tracking->srcs, 0);
  30                 }
  31                 tracking->spec.src = NULL;
  32         }
  33
  34         return 0;
  35 }
  36
  37 static int should_setup_rebase(const char *origin)
  38 {
  39         switch (autorebase) {
  40         case AUTOREBASE_NEVER:
  41                 return 0;
  42         case AUTOREBASE_LOCAL:
  43                 return origin == NULL;
  44         case AUTOREBASE_REMOTE:
  45                 return origin != NULL;
  46         case AUTOREBASE_ALWAYS:
  47                 return 1;
  48         }
  49         return 0;
  50 }
  51
  52 /**
  53  * Install upstream tracking configuration for a branch; specifically, add
  54  * `branch.<name>.remote` and `branch.<name>.merge` entries.
  55  *
  56  * `flag` contains integer flags for options; currently only
  57  * BRANCH_CONFIG_VERBOSE is checked.
  58  *
  59  * `local` is the name of the branch whose configuration we're installing.
  60  *
  61  * `origin` is the name of the remote owning the upstream branches. NULL means
  62  * the upstream branches are local to this repo.
  63  *
  64  * `remotes` is a list of refs that are upstream of local
  65  */
  66 static int install_branch_config_multiple_remotes(int flag, const char *local,
  67                 const char *origin, struct string_list *remotes)
  68 {
  69         const char *shortname = NULL;
  70         struct strbuf key = STRBUF_INIT;
  71         struct string_list_item *item;
  72         int rebasing = should_setup_rebase(origin);
  73
  74         if (!remotes->nr)
  75                 BUG("must provide at least one remote for branch config");
  76         if (rebasing && remotes->nr > 1)
  77                 die(_("cannot inherit upstream tracking configuration of "
  78                       "multiple refs when rebasing is requested"));
  79
  80         /*
  81          * If the new branch is trying to track itself, something has gone
  82          * wrong. Warn the user and don't proceed any further.
  83          */
  84         if (!origin)
  85                 for_each_string_list_item(item, remotes)
  86                         if (skip_prefix(item->string, "refs/heads/", &shortname)
  87                             && !strcmp(local, shortname)) {
  88                                 warning(_("not setting branch '%s' as its own upstream."),
  89                                         local);
  90                                 return 0;
  91                         }
  92
  93         strbuf_addf(&key, "branch.%s.remote", local);
  94         if (git_config_set_gently(key.buf, origin ? origin : ".") < 0)
  95                 goto out_err;
  96
  97         strbuf_reset(&key);
  98         strbuf_addf(&key, "branch.%s.merge", local);
  99         /*
 100          * We want to overwrite any existing config with all the branches in
 101          * "remotes". Override any existing config, then write our branches. If
 102          * more than one is provided, use CONFIG_REGEX_NONE to preserve what
 103          * we've written so far.
 104          */
 105         if (git_config_set_gently(key.buf, NULL) < 0)
 106                 goto out_err;
 107         for_each_string_list_item(item, remotes)
 108                 if (git_config_set_multivar_gently(key.buf, item->string, CONFIG_REGEX_NONE, 0) < 0)
 109                         goto out_err;
 110
 111         if (rebasing) {
 112                 strbuf_reset(&key);
 113                 strbuf_addf(&key, "branch.%s.rebase", local);
 114                 if (git_config_set_gently(key.buf, "true") < 0)
 115                         goto out_err;
 116         }
 117         strbuf_release(&key);
 118
 119         if (flag & BRANCH_CONFIG_VERBOSE) {
 120                 struct strbuf tmp_ref_name = STRBUF_INIT;
 121                 struct string_list friendly_ref_names = STRING_LIST_INIT_DUP;
 122
 123                 for_each_string_list_item(item, remotes) {
 124                         shortname = item->string;
 125                         skip_prefix(shortname, "refs/heads/", &shortname);
 126                         if (origin) {
 127                                 strbuf_addf(&tmp_ref_name, "%s/%s",
 128                                             origin, shortname);
 129                                 string_list_append_nodup(
 130                                         &friendly_ref_names,
 131                                         strbuf_detach(&tmp_ref_name, NULL));
 132                         } else {
 133                                 string_list_append(
 134                                         &friendly_ref_names, shortname);
 135                         }
 136                 }
 137
 138                 if (remotes->nr == 1) {
 139                         /*
 140                          * Rebasing is only allowed in the case of a single
 141                          * upstream branch.
 142                          */
 143                         printf_ln(rebasing ?
 144                                 _("branch '%s' set up to track '%s' by rebasing.") :
 145                                 _("branch '%s' set up to track '%s'."),
 146                                 local, friendly_ref_names.items[0].string);
 147                 } else {
 148                         printf_ln(_("branch '%s' set up to track:"), local);
 149                         for_each_string_list_item(item, &friendly_ref_names)
 150                                 printf_ln("  %s", item->string);
 151                 }
 152
 153                 string_list_clear(&friendly_ref_names, 0);
 154         }
 155
 156         return 0;
 157
 158 out_err:
 159         strbuf_release(&key);
 160         error(_("Unable to write upstream branch configuration"));
 161
 162         advise(_("\nAfter fixing the error cause you may try to fix up\n"
 163                 "the remote tracking information by invoking:"));
 164         if (remotes->nr == 1)
 165                 advise("  git branch --set-upstream-to=%s%s%s",
 166                         origin ? origin : "",
 167                         origin ? "/" : "",
 168                         remotes->items[0].string);
 169         else {
 170                 advise("  git config --add branch.\"%s\".remote %s",
 171                         local, origin ? origin : ".");
 172                 for_each_string_list_item(item, remotes)
 173                         advise("  git config --add branch.\"%s\".merge %s",
 174                                 local, item->string);
 175         }
 176
 177         return -1;
 178 }
 179
 180 int install_branch_config(int flag, const char *local, const char *origin,
 181                 const char *remote)
 182 {
 183         int ret;
 184         struct string_list remotes = STRING_LIST_INIT_DUP;
 185
 186         string_list_append(&remotes, remote);
 187         ret = install_branch_config_multiple_remotes(flag, local, origin, &remotes);
 188         string_list_clear(&remotes, 0);
 189         return ret;
 190 }
 191
 192 static int inherit_tracking(struct tracking *tracking, const char *orig_ref)
 193 {
 194         const char *bare_ref;
 195         struct branch *branch;
 196         int i;
 197
 198         bare_ref = orig_ref;
 199         skip_prefix(orig_ref, "refs/heads/", &bare_ref);
 200
 201         branch = branch_get(bare_ref);
 202         if (!branch->remote_name) {
 203                 warning(_("asked to inherit tracking from '%s', but no remote is set"),
 204                         bare_ref);
 205                 return -1;
 206         }
 207
 208         if (branch->merge_nr < 1 || !branch->merge_name || !branch->merge_name[0]) {
 209                 warning(_("asked to inherit tracking from '%s', but no merge configuration is set"),
 210                         bare_ref);
 211                 return -1;
 212         }
 213
 214         tracking->remote = xstrdup(branch->remote_name);
 215         for (i = 0; i < branch->merge_nr; i++)
 216                 string_list_append(tracking->srcs, branch->merge_name[i]);
 217         return 0;
 218 }
 219
 220 /*
 221  * This is called when new_ref is branched off of orig_ref, and tries
 222  * to infer the settings for branch.<new_ref>.{remote,merge} from the
 223  * config.
 224  */
 225 static void setup_tracking(const char *new_ref, const char *orig_ref,
 226                            enum branch_track track, int quiet)
 227 {
 228         struct tracking tracking;
 229         struct string_list tracking_srcs = STRING_LIST_INIT_DUP;
 230         int config_flags = quiet ? 0 : BRANCH_CONFIG_VERBOSE;
 231
 232         memset(&tracking, 0, sizeof(tracking));
 233         tracking.spec.dst = (char *)orig_ref;
 234         tracking.srcs = &tracking_srcs;
 235         if (track != BRANCH_TRACK_INHERIT)
 236                 for_each_remote(find_tracked_branch, &tracking);
 237         else if (inherit_tracking(&tracking, orig_ref))
 238                 return;
 239
 240         if (!tracking.matches)
 241                 switch (track) {
 242                 case BRANCH_TRACK_ALWAYS:
 243                 case BRANCH_TRACK_EXPLICIT:
 244                 case BRANCH_TRACK_OVERRIDE:
 245                 case BRANCH_TRACK_INHERIT:
 246                         break;
 247                 default:
 248                         return;
 249                 }
 250
 251         if (tracking.matches > 1)
 252                 die(_("Not tracking: ambiguous information for ref %s"),
 253                     orig_ref);
 254
 255         if (tracking.srcs->nr < 1)
 256                 string_list_append(tracking.srcs, orig_ref);
 257         if (install_branch_config_multiple_remotes(config_flags, new_ref,
 258                                 tracking.remote, tracking.srcs) < 0)
 259                 exit(-1);
 260
 261         string_list_clear(tracking.srcs, 0);
 262 }
 263
 264 int read_branch_desc(struct strbuf *buf, const char *branch_name)
 265 {
 266         char *v = NULL;
 267         struct strbuf name = STRBUF_INIT;
 268         strbuf_addf(&name, "branch.%s.description", branch_name);
 269         if (git_config_get_string(name.buf, &v)) {
 270                 strbuf_release(&name);
 271                 return -1;
 272         }
 273         strbuf_addstr(buf, v);
 274         free(v);
 275         strbuf_release(&name);
 276         return 0;
 277 }
 278
 279 /*
 280  * Check if 'name' can be a valid name for a branch; die otherwise.
 281  * Return 1 if the named branch already exists; return 0 otherwise.
 282  * Fill ref with the full refname for the branch.
 283  */
 284 int validate_branchname(const char *name, struct strbuf *ref)
 285 {
 286         if (strbuf_check_branch_ref(ref, name))
 287                 die(_("'%s' is not a valid branch name."), name);
 288
 289         return ref_exists(ref->buf);
 290 }
 291
 292 /*
 293  * Check if a branch 'name' can be created as a new branch; die otherwise.
 294  * 'force' can be used when it is OK for the named branch already exists.
 295  * Return 1 if the named branch already exists; return 0 otherwise.
 296  * Fill ref with the full refname for the branch.
 297  */
 298 int validate_new_branchname(const char *name, struct strbuf *ref, int force)
 299 {
 300         const char *head;
 301
 302         if (!validate_branchname(name, ref))
 303                 return 0;
 304
 305         if (!force)
 306                 die(_("A branch named '%s' already exists."),
 307                     ref->buf + strlen("refs/heads/"));
 308
 309         head = resolve_ref_unsafe("HEAD", 0, NULL, NULL);
 310         if (!is_bare_repository() && head && !strcmp(head, ref->buf))
 311                 die(_("Cannot force update the current branch."));
 312
 313         return 1;
 314 }
 315
 316 static int check_tracking_branch(struct remote *remote, void *cb_data)
 317 {
 318         char *tracking_branch = cb_data;
 319         struct refspec_item query;
 320         memset(&query, 0, sizeof(struct refspec_item));
 321         query.dst = tracking_branch;
 322         return !remote_find_tracking(remote, &query);
 323 }
 324
 325 static int validate_remote_tracking_branch(char *ref)
 326 {
 327         return !for_each_remote(check_tracking_branch, ref);
 328 }
 329
 330 static const char upstream_not_branch[] =
 331 N_("Cannot setup tracking information; starting point '%s' is not a branch.");
 332 static const char upstream_missing[] =
 333 N_("the requested upstream branch '%s' does not exist");
 334 static const char upstream_advice[] =
 335 N_("\n"
 336 "If you are planning on basing your work on an upstream\n"
 337 "branch that already exists at the remote, you may need to\n"
 338 "run \"git fetch\" to retrieve it.\n"
 339 "\n"
 340 "If you are planning to push out a new local branch that\n"
 341 "will track its remote counterpart, you may want to use\n"
 342 "\"git push -u\" to set the upstream config as you push.");
 343
 344 void create_branch(struct repository *r,
 345                    const char *name, const char *start_name,
 346                    int force, int clobber_head_ok, int reflog,
 347                    int quiet, enum branch_track track)
 348 {
 349         struct commit *commit;
 350         struct object_id oid;
 351         char *real_ref;
 352         struct strbuf ref = STRBUF_INIT;
 353         int forcing = 0;
 354         int dont_change_ref = 0;
 355         int explicit_tracking = 0;
 356
 357         if (track == BRANCH_TRACK_EXPLICIT || track == BRANCH_TRACK_OVERRIDE)
 358                 explicit_tracking = 1;
 359
 360         if ((track == BRANCH_TRACK_OVERRIDE || clobber_head_ok)
 361             ? validate_branchname(name, &ref)
 362             : validate_new_branchname(name, &ref, force)) {
 363                 if (!force)
 364                         dont_change_ref = 1;
 365                 else
 366                         forcing = 1;
 367         }
 368
 369         real_ref = NULL;
 370         if (get_oid_mb(start_name, &oid)) {
 371                 if (explicit_tracking) {
 372                         if (advice_enabled(ADVICE_SET_UPSTREAM_FAILURE)) {
 373                                 error(_(upstream_missing), start_name);
 374                                 advise(_(upstream_advice));
 375                                 exit(1);
 376                         }
 377                         die(_(upstream_missing), start_name);
 378                 }
 379                 die(_("Not a valid object name: '%s'."), start_name);
 380         }
 381
 382         switch (dwim_ref(start_name, strlen(start_name), &oid, &real_ref, 0)) {
 383         case 0:
 384                 /* Not branching from any existing branch */
 385                 if (explicit_tracking)
 386                         die(_(upstream_not_branch), start_name);
 387                 break;
 388         case 1:
 389                 /* Unique completion -- good, only if it is a real branch */
 390                 if (!starts_with(real_ref, "refs/heads/") &&
 391                     validate_remote_tracking_branch(real_ref)) {
 392                         if (explicit_tracking)
 393                                 die(_(upstream_not_branch), start_name);
 394                         else
 395                                 FREE_AND_NULL(real_ref);
 396                 }
 397                 break;
 398         default:
 399                 die(_("Ambiguous object name: '%s'."), start_name);
 400                 break;
 401         }
 402
 403         if ((commit = lookup_commit_reference(r, &oid)) == NULL)
 404                 die(_("Not a valid branch point: '%s'."), start_name);
 405         oidcpy(&oid, &commit->object.oid);
 406
 407         if (reflog)
 408                 log_all_ref_updates = LOG_REFS_NORMAL;
 409
 410         if (!dont_change_ref) {
 411                 struct ref_transaction *transaction;
 412                 struct strbuf err = STRBUF_INIT;
 413                 char *msg;
 414
 415                 if (forcing)
 416                         msg = xstrfmt("branch: Reset to %s", start_name);
 417                 else
 418                         msg = xstrfmt("branch: Created from %s", start_name);
 419
 420                 transaction = ref_transaction_begin(&err);
 421                 if (!transaction ||
 422                     ref_transaction_update(transaction, ref.buf,
 423                                            &oid, forcing ? NULL : null_oid(),
 424                                            0, msg, &err) ||
 425                     ref_transaction_commit(transaction, &err))
 426                         die("%s", err.buf);
 427                 ref_transaction_free(transaction);
 428                 strbuf_release(&err);
 429                 free(msg);
 430         }
 431
 432         if (real_ref && track)
 433                 setup_tracking(ref.buf + 11, real_ref, track, quiet);
 434
 435         strbuf_release(&ref);
 436         free(real_ref);
 437 }
 438
 439 void remove_merge_branch_state(struct repository *r)
 440 {
 441         unlink(git_path_merge_head(r));
 442         unlink(git_path_merge_rr(r));
 443         unlink(git_path_merge_msg(r));
 444         unlink(git_path_merge_mode(r));
 445         unlink(git_path_auto_merge(r));
 446         save_autostash(git_path_merge_autostash(r));
 447 }
 448
 449 void remove_branch_state(struct repository *r, int verbose)
 450 {
 451         sequencer_post_commit_cleanup(r, verbose);
 452         unlink(git_path_squash_msg(r));
 453         remove_merge_branch_state(r);
 454 }
 455
 456 void die_if_checked_out(const char *branch, int ignore_current_worktree)
 457 {
 458         const struct worktree *wt;
 459
 460         wt = find_shared_symref("HEAD", branch);
 461         if (!wt || (ignore_current_worktree && wt->is_current))
 462                 return;
 463         skip_prefix(branch, "refs/heads/", &branch);
 464         die(_("'%s' is already checked out at '%s'"),
 465             branch, wt->path);
 466 }
 467
 468 int replace_each_worktree_head_symref(const char *oldref, const char *newref,
 469                                       const char *logmsg)
 470 {
 471         int ret = 0;
 472         struct worktree **worktrees = get_worktrees();
 473         int i;
 474
 475         for (i = 0; worktrees[i]; i++) {
 476                 struct ref_store *refs;
 477
 478                 if (worktrees[i]->is_detached)
 479                         continue;
 480                 if (!worktrees[i]->head_ref)
 481                         continue;
 482                 if (strcmp(oldref, worktrees[i]->head_ref))
 483                         continue;
 484
 485                 refs = get_worktree_ref_store(worktrees[i]);
 486                 if (refs_create_symref(refs, "HEAD", newref, logmsg))
 487                         ret = error(_("HEAD of working tree %s is not updated"),
 488                                     worktrees[i]->path);
 489         }
 490
 491         free_worktrees(worktrees);
 492         return ret;
 493 }