branch.c

   1 #include "git-compat-util.h"
   2 #include "cache.h"
   3 #include "branch.h"
   4 #include "refs.h"
   5 #include "remote.h"
   6 #include "commit.h"
   7 #include "worktree.h"
   8
   9 struct tracking {
  10         struct refspec spec;
  11         char *src;
  12         const char *remote;
  13         int matches;
  14 };
  15
  16 static int find_tracked_branch(struct remote *remote, void *priv)
  17 {
  18         struct tracking *tracking = priv;
  19
  20         if (!remote_find_tracking(remote, &tracking->spec)) {
  21                 if (++tracking->matches == 1) {
  22                         tracking->src = tracking->spec.src;
  23                         tracking->remote = remote->name;
  24                 } else {
  25                         free(tracking->spec.src);
  26                         if (tracking->src) {
  27                                 free(tracking->src);
  28                                 tracking->src = NULL;
  29                         }
  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 static const char tracking_advice[] =
  53 N_("\n"
  54 "After fixing the error cause you may try to fix up\n"
  55 "the remote tracking information by invoking\n"
  56 "\"git branch --set-upstream-to=%s%s%s\".");
  57
  58 int install_branch_config(int flag, const char *local, const char *origin, const char *remote)
  59 {
  60         const char *shortname = NULL;
  61         struct strbuf key = STRBUF_INIT;
  62         int rebasing = should_setup_rebase(origin);
  63
  64         if (skip_prefix(remote, "refs/heads/", &shortname)
  65             && !strcmp(local, shortname)
  66             && !origin) {
  67                 warning(_("Not setting branch %s as its own upstream."),
  68                         local);
  69                 return 0;
  70         }
  71
  72         strbuf_addf(&key, "branch.%s.remote", local);
  73         if (git_config_set(key.buf, origin ? origin : ".") < 0)
  74                 goto out_err;
  75
  76         strbuf_reset(&key);
  77         strbuf_addf(&key, "branch.%s.merge", local);
  78         if (git_config_set(key.buf, remote) < 0)
  79                 goto out_err;
  80
  81         if (rebasing) {
  82                 strbuf_reset(&key);
  83                 strbuf_addf(&key, "branch.%s.rebase", local);
  84                 if (git_config_set(key.buf, "true") < 0)
  85                         goto out_err;
  86         }
  87         strbuf_release(&key);
  88
  89         if (flag & BRANCH_CONFIG_VERBOSE) {
  90                 if (shortname) {
  91                         if (origin)
  92                                 printf_ln(rebasing ?
  93                                           _("Branch %s set up to track remote branch %s from %s by rebasing.") :
  94                                           _("Branch %s set up to track remote branch %s from %s."),
  95                                           local, shortname, origin);
  96                         else
  97                                 printf_ln(rebasing ?
  98                                           _("Branch %s set up to track local branch %s by rebasing.") :
  99                                           _("Branch %s set up to track local branch %s."),
 100                                           local, shortname);
 101                 } else {
 102                         if (origin)
 103                                 printf_ln(rebasing ?
 104                                           _("Branch %s set up to track remote ref %s by rebasing.") :
 105                                           _("Branch %s set up to track remote ref %s."),
 106                                           local, remote);
 107                         else
 108                                 printf_ln(rebasing ?
 109                                           _("Branch %s set up to track local ref %s by rebasing.") :
 110                                           _("Branch %s set up to track local ref %s."),
 111                                           local, remote);
 112                 }
 113         }
 114
 115         return 0;
 116
 117 out_err:
 118         strbuf_release(&key);
 119         error(_("Unable to write upstream branch configuration"));
 120
 121         advise(_(tracking_advice),
 122                origin ? origin : "",
 123                origin ? "/" : "",
 124                shortname ? shortname : remote);
 125
 126         return -1;
 127 }
 128
 129 /*
 130  * This is called when new_ref is branched off of orig_ref, and tries
 131  * to infer the settings for branch.<new_ref>.{remote,merge} from the
 132  * config.
 133  */
 134 static void setup_tracking(const char *new_ref, const char *orig_ref,
 135                            enum branch_track track, int quiet)
 136 {
 137         struct tracking tracking;
 138         int config_flags = quiet ? 0 : BRANCH_CONFIG_VERBOSE;
 139
 140         memset(&tracking, 0, sizeof(tracking));
 141         tracking.spec.dst = (char *)orig_ref;
 142         if (for_each_remote(find_tracked_branch, &tracking))
 143                 return;
 144
 145         if (!tracking.matches)
 146                 switch (track) {
 147                 case BRANCH_TRACK_ALWAYS:
 148                 case BRANCH_TRACK_EXPLICIT:
 149                 case BRANCH_TRACK_OVERRIDE:
 150                         break;
 151                 default:
 152                         return;
 153                 }
 154
 155         if (tracking.matches > 1)
 156                 die(_("Not tracking: ambiguous information for ref %s"),
 157                     orig_ref);
 158
 159         if (install_branch_config(config_flags, new_ref, tracking.remote,
 160                               tracking.src ? tracking.src : orig_ref) < 0)
 161                 exit(-1);
 162
 163         free(tracking.src);
 164 }
 165
 166 int read_branch_desc(struct strbuf *buf, const char *branch_name)
 167 {
 168         char *v = NULL;
 169         struct strbuf name = STRBUF_INIT;
 170         strbuf_addf(&name, "branch.%s.description", branch_name);
 171         if (git_config_get_string(name.buf, &v)) {
 172                 strbuf_release(&name);
 173                 return -1;
 174         }
 175         strbuf_addstr(buf, v);
 176         free(v);
 177         strbuf_release(&name);
 178         return 0;
 179 }
 180
 181 int validate_new_branchname(const char *name, struct strbuf *ref,
 182                             int force, int attr_only)
 183 {
 184         if (strbuf_check_branch_ref(ref, name))
 185                 die(_("'%s' is not a valid branch name."), name);
 186
 187         if (!ref_exists(ref->buf))
 188                 return 0;
 189         else if (!force && !attr_only)
 190                 die(_("A branch named '%s' already exists."), ref->buf + strlen("refs/heads/"));
 191
 192         if (!attr_only) {
 193                 const char *head;
 194                 unsigned char sha1[20];
 195
 196                 head = resolve_ref_unsafe("HEAD", 0, sha1, NULL);
 197                 if (!is_bare_repository() && head && !strcmp(head, ref->buf))
 198                         die(_("Cannot force update the current branch."));
 199         }
 200         return 1;
 201 }
 202
 203 static int check_tracking_branch(struct remote *remote, void *cb_data)
 204 {
 205         char *tracking_branch = cb_data;
 206         struct refspec query;
 207         memset(&query, 0, sizeof(struct refspec));
 208         query.dst = tracking_branch;
 209         return !remote_find_tracking(remote, &query);
 210 }
 211
 212 static int validate_remote_tracking_branch(char *ref)
 213 {
 214         return !for_each_remote(check_tracking_branch, ref);
 215 }
 216
 217 static const char upstream_not_branch[] =
 218 N_("Cannot setup tracking information; starting point '%s' is not a branch.");
 219 static const char upstream_missing[] =
 220 N_("the requested upstream branch '%s' does not exist");
 221 static const char upstream_advice[] =
 222 N_("\n"
 223 "If you are planning on basing your work on an upstream\n"
 224 "branch that already exists at the remote, you may need to\n"
 225 "run \"git fetch\" to retrieve it.\n"
 226 "\n"
 227 "If you are planning to push out a new local branch that\n"
 228 "will track its remote counterpart, you may want to use\n"
 229 "\"git push -u\" to set the upstream config as you push.");
 230
 231 void create_branch(const char *head,
 232                    const char *name, const char *start_name,
 233                    int force, int reflog, int clobber_head,
 234                    int quiet, enum branch_track track)
 235 {
 236         struct commit *commit;
 237         unsigned char sha1[20];
 238         char *real_ref, msg[PATH_MAX + 20];
 239         struct strbuf ref = STRBUF_INIT;
 240         int forcing = 0;
 241         int dont_change_ref = 0;
 242         int explicit_tracking = 0;
 243
 244         if (track == BRANCH_TRACK_EXPLICIT || track == BRANCH_TRACK_OVERRIDE)
 245                 explicit_tracking = 1;
 246
 247         if (validate_new_branchname(name, &ref, force,
 248                                     track == BRANCH_TRACK_OVERRIDE ||
 249                                     clobber_head)) {
 250                 if (!force)
 251                         dont_change_ref = 1;
 252                 else
 253                         forcing = 1;
 254         }
 255
 256         real_ref = NULL;
 257         if (get_sha1(start_name, sha1)) {
 258                 if (explicit_tracking) {
 259                         if (advice_set_upstream_failure) {
 260                                 error(_(upstream_missing), start_name);
 261                                 advise(_(upstream_advice));
 262                                 exit(1);
 263                         }
 264                         die(_(upstream_missing), start_name);
 265                 }
 266                 die(_("Not a valid object name: '%s'."), start_name);
 267         }
 268
 269         switch (dwim_ref(start_name, strlen(start_name), sha1, &real_ref)) {
 270         case 0:
 271                 /* Not branching from any existing branch */
 272                 if (explicit_tracking)
 273                         die(_(upstream_not_branch), start_name);
 274                 break;
 275         case 1:
 276                 /* Unique completion -- good, only if it is a real branch */
 277                 if (!starts_with(real_ref, "refs/heads/") &&
 278                     validate_remote_tracking_branch(real_ref)) {
 279                         if (explicit_tracking)
 280                                 die(_(upstream_not_branch), start_name);
 281                         else
 282                                 real_ref = NULL;
 283                 }
 284                 break;
 285         default:
 286                 die(_("Ambiguous object name: '%s'."), start_name);
 287                 break;
 288         }
 289
 290         if ((commit = lookup_commit_reference(sha1)) == NULL)
 291                 die(_("Not a valid branch point: '%s'."), start_name);
 292         hashcpy(sha1, commit->object.oid.hash);
 293
 294         if (forcing)
 295                 snprintf(msg, sizeof msg, "branch: Reset to %s",
 296                          start_name);
 297         else if (!dont_change_ref)
 298                 snprintf(msg, sizeof msg, "branch: Created from %s",
 299                          start_name);
 300
 301         if (reflog)
 302                 log_all_ref_updates = 1;
 303
 304         if (!dont_change_ref) {
 305                 struct ref_transaction *transaction;
 306                 struct strbuf err = STRBUF_INIT;
 307
 308                 transaction = ref_transaction_begin(&err);
 309                 if (!transaction ||
 310                     ref_transaction_update(transaction, ref.buf,
 311                                            sha1, forcing ? NULL : null_sha1,
 312                                            0, msg, &err) ||
 313                     ref_transaction_commit(transaction, &err))
 314                         die("%s", err.buf);
 315                 ref_transaction_free(transaction);
 316                 strbuf_release(&err);
 317         }
 318
 319         if (real_ref && track)
 320                 setup_tracking(ref.buf + 11, real_ref, track, quiet);
 321
 322         strbuf_release(&ref);
 323         free(real_ref);
 324 }
 325
 326 void remove_branch_state(void)
 327 {
 328         unlink(git_path_cherry_pick_head());
 329         unlink(git_path_revert_head());
 330         unlink(git_path_merge_head());
 331         unlink(git_path_merge_rr());
 332         unlink(git_path_merge_msg());
 333         unlink(git_path_merge_mode());
 334         unlink(git_path_squash_msg());
 335 }
 336
 337 void die_if_checked_out(const char *branch)
 338 {
 339         char *existing;
 340
 341         existing = find_shared_symref("HEAD", branch);
 342         if (existing) {
 343                 skip_prefix(branch, "refs/heads/", &branch);
 344                 die(_("'%s' is already checked out at '%s'"), branch, existing);
 345         }
 346 }