1acbd4e6d37a536c9236528d616a418d84f44ba1
   1#include "cache.h"
   2#include "branch.h"
   3#include "refs.h"
   4#include "remote.h"
   5#include "commit.h"
   6
   7struct tracking {
   8        struct refspec spec;
   9        char *src;
  10        const char *remote;
  11        int matches;
  12};
  13
  14static 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->name;
  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
  35static int should_setup_rebase(const char *origin)
  36{
  37        switch (autorebase) {
  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
  50void install_branch_config(int flag, const char *local, const char *origin, const char *remote)
  51{
  52        const char *shortname = remote + 11;
  53        int remote_is_branch = !prefixcmp(remote, "refs/heads/");
  54        struct strbuf key = STRBUF_INIT;
  55        int rebasing = should_setup_rebase(origin);
  56
  57        if (remote_is_branch
  58            && !strcmp(local, shortname)
  59            && !origin) {
  60                warning("Not setting branch %s as its own upstream.",
  61                        local);
  62                return;
  63        }
  64
  65        strbuf_addf(&key, "branch.%s.remote", local);
  66        git_config_set(key.buf, origin ? origin : ".");
  67
  68        strbuf_reset(&key);
  69        strbuf_addf(&key, "branch.%s.merge", local);
  70        git_config_set(key.buf, remote);
  71
  72        if (rebasing) {
  73                strbuf_reset(&key);
  74                strbuf_addf(&key, "branch.%s.rebase", local);
  75                git_config_set(key.buf, "true");
  76        }
  77        strbuf_release(&key);
  78
  79        if (flag & BRANCH_CONFIG_VERBOSE) {
  80                if (remote_is_branch && origin)
  81                        printf(rebasing ?
  82                               "Branch %s set up to track remote branch %s from %s by rebasing.\n" :
  83                               "Branch %s set up to track remote branch %s from %s.\n",
  84                               local, shortname, origin);
  85                else if (remote_is_branch && !origin)
  86                        printf(rebasing ?
  87                               "Branch %s set up to track local branch %s by rebasing.\n" :
  88                               "Branch %s set up to track local branch %s.\n",
  89                               local, shortname);
  90                else if (!remote_is_branch && origin)
  91                        printf(rebasing ?
  92                               "Branch %s set up to track remote ref %s by rebasing.\n" :
  93                               "Branch %s set up to track remote ref %s.\n",
  94                               local, remote);
  95                else if (!remote_is_branch && !origin)
  96                        printf(rebasing ?
  97                               "Branch %s set up to track local ref %s by rebasing.\n" :
  98                               "Branch %s set up to track local ref %s.\n",
  99                               local, remote);
 100                else
 101                        die("BUG: impossible combination of %d and %p",
 102                            remote_is_branch, origin);
 103        }
 104}
 105
 106/*
 107 * This is called when new_ref is branched off of orig_ref, and tries
 108 * to infer the settings for branch.<new_ref>.{remote,merge} from the
 109 * config.
 110 */
 111static int setup_tracking(const char *new_ref, const char *orig_ref,
 112                          enum branch_track track, int quiet)
 113{
 114        struct tracking tracking;
 115        int config_flags = quiet ? 0 : BRANCH_CONFIG_VERBOSE;
 116
 117        if (strlen(new_ref) > 1024 - 7 - 7 - 1)
 118                return error("Tracking not set up: name too long: %s",
 119                                new_ref);
 120
 121        memset(&tracking, 0, sizeof(tracking));
 122        tracking.spec.dst = (char *)orig_ref;
 123        if (for_each_remote(find_tracked_branch, &tracking))
 124                return 1;
 125
 126        if (!tracking.matches)
 127                switch (track) {
 128                case BRANCH_TRACK_ALWAYS:
 129                case BRANCH_TRACK_EXPLICIT:
 130                case BRANCH_TRACK_OVERRIDE:
 131                        break;
 132                default:
 133                        return 1;
 134                }
 135
 136        if (tracking.matches > 1)
 137                return error("Not tracking: ambiguous information for ref %s",
 138                                orig_ref);
 139
 140        install_branch_config(config_flags, new_ref, tracking.remote,
 141                              tracking.src ? tracking.src : orig_ref);
 142
 143        free(tracking.src);
 144        return 0;
 145}
 146
 147struct branch_desc_cb {
 148        const char *config_name;
 149        const char *value;
 150};
 151
 152static int read_branch_desc_cb(const char *var, const char *value, void *cb)
 153{
 154        struct branch_desc_cb *desc = cb;
 155        if (strcmp(desc->config_name, var))
 156                return 0;
 157        free((char *)desc->value);
 158        return git_config_string(&desc->value, var, value);
 159}
 160
 161int read_branch_desc(struct strbuf *buf, const char *branch_name)
 162{
 163        struct branch_desc_cb cb;
 164        struct strbuf name = STRBUF_INIT;
 165        strbuf_addf(&name, "branch.%s.description", branch_name);
 166        cb.config_name = name.buf;
 167        cb.value = NULL;
 168        if (git_config(read_branch_desc_cb, &cb) < 0) {
 169                strbuf_release(&name);
 170                return -1;
 171        }
 172        if (cb.value)
 173                strbuf_addstr(buf, cb.value);
 174        strbuf_release(&name);
 175        return 0;
 176}
 177
 178int validate_new_branchname(const char *name, struct strbuf *ref,
 179                            int force, int attr_only)
 180{
 181        if (strbuf_check_branch_ref(ref, name))
 182                die("'%s' is not a valid branch name.", name);
 183
 184        if (!ref_exists(ref->buf))
 185                return 0;
 186        else if (!force && !attr_only)
 187                die("A branch named '%s' already exists.", ref->buf + strlen("refs/heads/"));
 188
 189        if (!attr_only) {
 190                const char *head;
 191                unsigned char sha1[20];
 192
 193                head = resolve_ref_unsafe("HEAD", sha1, 0, NULL);
 194                if (!is_bare_repository() && head && !strcmp(head, ref->buf))
 195                        die("Cannot force update the current branch.");
 196        }
 197        return 1;
 198}
 199
 200static const char upstream_not_branch[] =
 201N_("Cannot setup tracking information; starting point is not a branch.");
 202
 203void create_branch(const char *head,
 204                   const char *name, const char *start_name,
 205                   int force, int reflog, int clobber_head,
 206                   int quiet, enum branch_track track)
 207{
 208        struct ref_lock *lock = NULL;
 209        struct commit *commit;
 210        unsigned char sha1[20];
 211        char *real_ref, msg[PATH_MAX + 20];
 212        struct strbuf ref = STRBUF_INIT;
 213        int forcing = 0;
 214        int dont_change_ref = 0;
 215        int explicit_tracking = 0;
 216
 217        if (track == BRANCH_TRACK_EXPLICIT || track == BRANCH_TRACK_OVERRIDE)
 218                explicit_tracking = 1;
 219
 220        if (validate_new_branchname(name, &ref, force,
 221                                    track == BRANCH_TRACK_OVERRIDE ||
 222                                    clobber_head)) {
 223                if (!force)
 224                        dont_change_ref = 1;
 225                else
 226                        forcing = 1;
 227        }
 228
 229        real_ref = NULL;
 230        if (get_sha1(start_name, sha1))
 231                die("Not a valid object name: '%s'.", start_name);
 232
 233        switch (dwim_ref(start_name, strlen(start_name), sha1, &real_ref)) {
 234        case 0:
 235                /* Not branching from any existing branch */
 236                if (explicit_tracking)
 237                        die(_(upstream_not_branch));
 238                break;
 239        case 1:
 240                /* Unique completion -- good, only if it is a real branch */
 241                if (prefixcmp(real_ref, "refs/heads/") &&
 242                    prefixcmp(real_ref, "refs/remotes/")) {
 243                        if (explicit_tracking)
 244                                die(_(upstream_not_branch));
 245                        else
 246                                real_ref = NULL;
 247                }
 248                break;
 249        default:
 250                die("Ambiguous object name: '%s'.", start_name);
 251                break;
 252        }
 253
 254        if ((commit = lookup_commit_reference(sha1)) == NULL)
 255                die("Not a valid branch point: '%s'.", start_name);
 256        hashcpy(sha1, commit->object.sha1);
 257
 258        if (!dont_change_ref) {
 259                lock = lock_any_ref_for_update(ref.buf, NULL, 0);
 260                if (!lock)
 261                        die_errno("Failed to lock ref for update");
 262        }
 263
 264        if (reflog)
 265                log_all_ref_updates = 1;
 266
 267        if (forcing)
 268                snprintf(msg, sizeof msg, "branch: Reset to %s",
 269                         start_name);
 270        else if (!dont_change_ref)
 271                snprintf(msg, sizeof msg, "branch: Created from %s",
 272                         start_name);
 273
 274        if (real_ref && track)
 275                setup_tracking(ref.buf+11, real_ref, track, quiet);
 276
 277        if (!dont_change_ref)
 278                if (write_ref_sha1(lock, sha1, msg) < 0)
 279                        die_errno("Failed to write ref");
 280
 281        strbuf_release(&ref);
 282        free(real_ref);
 283}
 284
 285void remove_branch_state(void)
 286{
 287        unlink(git_path("CHERRY_PICK_HEAD"));
 288        unlink(git_path("REVERT_HEAD"));
 289        unlink(git_path("MERGE_HEAD"));
 290        unlink(git_path("MERGE_RR"));
 291        unlink(git_path("MERGE_MSG"));
 292        unlink(git_path("MERGE_MODE"));
 293        unlink(git_path("SQUASH_MSG"));
 294}