branch.c

   1 #include "cache.h"
   2 #include "branch.h"
   3 #include "refs.h"
   4 #include "remote.h"
   5 #include "commit.h"
   6
   7 struct tracking {
   8         struct refspec spec;
   9         char *src;
  10         struct remote *remote;
  11         int matches;
  12 };
  13
  14 static int find_tracked_branch(struct remote *remote, void *priv)
  15 {
  16         struct tracking *tracking = priv;
  17
  18         if (!remote_find_tracking(remote, &tracking->spec)) {
  19                 if (++tracking->matches == 1) {
  20                         tracking->src = tracking->spec.src;
  21                         tracking->remote = remote;
  22                 } else {
  23                         free(tracking->spec.src);
  24                         if (tracking->src) {
  25                                 free(tracking->src);
  26                                 tracking->src = NULL;
  27                         }
  28                 }
  29                 tracking->spec.src = NULL;
  30         }
  31
  32         return 0;
  33 }
  34
  35 static int should_setup_rebase(struct remote *origin)
  36 {
  37         switch (origin ? origin->track.rebase : git_branch_track.rebase) {
  38         case AUTOREBASE_NEVER:
  39                 return 0;
  40         case AUTOREBASE_LOCAL:
  41                 return origin == NULL;
  42         case AUTOREBASE_REMOTE:
  43                 return origin != NULL;
  44         case AUTOREBASE_ALWAYS:
  45                 return 1;
  46         }
  47         return 0;
  48 }
  49
  50 void install_branch_config(int flag, const char *local, struct remote *remote,
  51                            const char *merge)
  52 {
  53         struct strbuf key = STRBUF_INIT;
  54         struct strbuf value = STRBUF_INIT;
  55         int rebasing = should_setup_rebase(remote);
  56
  57         strbuf_addf(&key, "branch.%s.remote", local);
  58         git_config_set(key.buf, remote ? remote->name : ".");
  59
  60         strbuf_reset(&key);
  61         strbuf_addf(&key, "branch.%s.merge", local);
  62         git_config_set(key.buf, merge);
  63
  64         if (remote && remote->track.push) {
  65                 strbuf_reset(&key);
  66                 strbuf_addf(&key, "remote.%s.push", remote->name);
  67                 strbuf_addf(&value, "refs/heads/%s:%s", local, merge);
  68                 git_config_set_multivar(key.buf, value.buf, "^$", 0);
  69         }
  70
  71         if (rebasing) {
  72                 strbuf_reset(&key);
  73                 strbuf_addf(&key, "branch.%s.rebase", local);
  74                 git_config_set(key.buf, "true");
  75         }
  76
  77         if (flag & BRANCH_CONFIG_VERBOSE) {
  78                 strbuf_reset(&key);
  79
  80                 strbuf_addstr(&key, remote ? "remote" : "local");
  81
  82                 /* Are we tracking a proper "branch"? */
  83                 if (!prefixcmp(merge, "refs/heads/"))
  84                         strbuf_addf(&key, " branch %s", merge + 11);
  85                 else
  86                         strbuf_addf(&key, " ref %s", merge);
  87                 if (remote)
  88                         strbuf_addf(&key, " from %s", remote->name);
  89                 printf("Branch %s set up to track %s%s.\n",
  90                        local, key.buf,
  91                        rebasing ? " by rebasing" : "");
  92         }
  93         strbuf_release(&key);
  94         strbuf_release(&value);
  95 }
  96
  97 static void strbuf_addstr_escape_re (struct strbuf *buf, const char *add)
  98 {
  99         const char *p = add;
 100         while ((add = strpbrk(add, ".*?+^$(){}[]")) != NULL) {
 101                 strbuf_add(buf, p, add - p);
 102                 strbuf_addf(buf, "\\%c", *add++);
 103                 p = add;
 104         }
 105         strbuf_addstr(buf, p);
 106 }
 107
 108 void delete_branch_config (const char *name)
 109 {
 110         struct strbuf buf = STRBUF_INIT;
 111         struct strbuf push_re = STRBUF_INIT;
 112         struct branch *branch;
 113
 114         if (prefixcmp(name, "refs/heads/"))
 115                 return;
 116
 117         /* git config --unset-all remote.foo.push ^\+?refs/heads/bar:  */
 118         branch = branch_get(name + 11);
 119         if (branch->remote_name) {
 120                 strbuf_addf(&buf, "remote.%s.push", branch->remote_name);
 121                 strbuf_addstr(&push_re, "^\\+?");
 122                 strbuf_addstr_escape_re(&push_re, name);
 123                 strbuf_addch(&push_re, ':');
 124                 if (git_config_set_multivar(buf.buf, NULL, push_re.buf, 1) < 0) {
 125                         warning("Update of config-file failed");
 126                         goto fail;
 127                 }
 128         }
 129         strbuf_reset(&buf);
 130         strbuf_addf(&buf, "branch.%s", name + 11);
 131         if (git_config_rename_section(buf.buf, NULL) < 0)
 132                 warning("Update of config-file failed");
 133
 134 fail:
 135         strbuf_release(&push_re);
 136         strbuf_release(&buf);
 137 }
 138
 139 /*
 140  * This is called when new_ref is branched off of orig_ref, and tries
 141  * to infer the settings for branch.<new_ref>.{remote,merge} from the
 142  * config.
 143  */
 144 static int setup_tracking(const char *new_ref, const char *orig_ref,
 145                           enum branch_track track)
 146 {
 147         struct tracking tracking;
 148
 149         if (strlen(new_ref) > 1024 - 7 - 7 - 1)
 150                 return error("Tracking not set up: name too long: %s",
 151                                 new_ref);
 152
 153         memset(&tracking, 0, sizeof(tracking));
 154         tracking.spec.dst = (char *)orig_ref;
 155         if (for_each_remote(find_tracked_branch, &tracking))
 156                 return 1;
 157
 158         if (track == BRANCH_TRACK_UNSPECIFIED) {
 159                 track = (tracking.remote
 160                          ? tracking.remote->track.merge : git_branch_track.merge);
 161                 if (!track)
 162                         return 0;
 163         }
 164
 165         if (!tracking.matches)
 166                 switch (track) {
 167                 case BRANCH_TRACK_ALWAYS:
 168                 case BRANCH_TRACK_EXPLICIT:
 169                         break;
 170                 default:
 171                         return 1;
 172                 }
 173
 174         if (tracking.matches > 1)
 175                 return error("Not tracking: ambiguous information for ref %s",
 176                                 orig_ref);
 177
 178         if (!tracking.src)
 179                 tracking.src = xstrdup (orig_ref);
 180
 181         install_branch_config(BRANCH_CONFIG_VERBOSE, new_ref, tracking.remote,
 182                               tracking.src);
 183         free(tracking.src);
 184         return 0;
 185 }
 186
 187 void create_branch(const char *head,
 188                    const char *name, const char *start_name,
 189                    int force, int reflog, enum branch_track track)
 190 {
 191         struct ref_lock *lock;
 192         struct commit *commit;
 193         unsigned char sha1[20];
 194         char *real_ref, msg[PATH_MAX + 20];
 195         struct strbuf ref = STRBUF_INIT;
 196         int forcing = 0;
 197
 198         if (strbuf_check_branch_ref(&ref, name))
 199                 die("'%s' is not a valid branch name.", name);
 200
 201         if (resolve_ref(ref.buf, sha1, 1, NULL)) {
 202                 if (!force)
 203                         die("A branch named '%s' already exists.", name);
 204                 else if (!is_bare_repository() && !strcmp(head, name))
 205                         die("Cannot force update the current branch.");
 206                 forcing = 1;
 207         }
 208
 209         real_ref = NULL;
 210         if (get_sha1(start_name, sha1))
 211                 die("Not a valid object name: '%s'.", start_name);
 212
 213         switch (dwim_ref(start_name, strlen(start_name), sha1, &real_ref)) {
 214         case 0:
 215                 /* Not branching from any existing branch */
 216                 if (track == BRANCH_TRACK_EXPLICIT)
 217                         die("Cannot setup tracking information; starting point is not a branch.");
 218                 break;
 219         case 1:
 220                 /* Unique completion -- good, only if it is a real ref */
 221                 if (track == BRANCH_TRACK_EXPLICIT && !strcmp(real_ref, "HEAD"))
 222                         die("Cannot setup tracking information; starting point is not a branch.");
 223                 break;
 224         default:
 225                 die("Ambiguous object name: '%s'.", start_name);
 226                 break;
 227         }
 228
 229         if ((commit = lookup_commit_reference(sha1)) == NULL)
 230                 die("Not a valid branch point: '%s'.", start_name);
 231         hashcpy(sha1, commit->object.sha1);
 232
 233         lock = lock_any_ref_for_update(ref.buf, NULL, 0);
 234         if (!lock)
 235                 die_errno("Failed to lock ref for update");
 236
 237         if (reflog)
 238                 log_all_ref_updates = 1;
 239
 240         if (forcing)
 241                 snprintf(msg, sizeof msg, "branch: Reset from %s",
 242                          start_name);
 243         else
 244                 snprintf(msg, sizeof msg, "branch: Created from %s",
 245                          start_name);
 246
 247         if (real_ref && track)
 248                 setup_tracking(name, real_ref, track);
 249
 250         if (write_ref_sha1(lock, sha1, msg) < 0)
 251                 die_errno("Failed to write ref");
 252
 253         strbuf_release(&ref);
 254         free(real_ref);
 255 }
 256
 257 void remove_branch_state(void)
 258 {
 259         unlink(git_path("MERGE_HEAD"));
 260         unlink(git_path("MERGE_RR"));
 261         unlink(git_path("MERGE_MSG"));
 262         unlink(git_path("MERGE_MODE"));
 263         unlink(git_path("SQUASH_MSG"));
 264 }