Andrew's git - gitweb.git/blob

   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
  35/*
  36 * This is called when new_ref is branched off of orig_ref, and tries
  37 * to infer the settings for branch.<new_ref>.{remote,merge} from the
  38 * config.
  39 */
  40static int setup_tracking(const char *new_ref, const char *orig_ref)
  41{
  42        char key[1024];
  43        struct tracking tracking;
  44
  45        if (strlen(new_ref) > 1024 - 7 - 7 - 1)
  46                return error("Tracking not set up: name too long: %s",
  47                                new_ref);
  48
  49        memset(&tracking, 0, sizeof(tracking));
  50        tracking.spec.dst = (char *)orig_ref;
  51        if (for_each_remote(find_tracked_branch, &tracking) ||
  52                        !tracking.matches)
  53                return 1;
  54
  55        if (tracking.matches > 1)
  56                return error("Not tracking: ambiguous information for ref %s",
  57                                orig_ref);
  58
  59        if (tracking.matches == 1) {
  60                sprintf(key, "branch.%s.remote", new_ref);
  61                git_config_set(key, tracking.remote ?  tracking.remote : ".");
  62                sprintf(key, "branch.%s.merge", new_ref);
  63                git_config_set(key, tracking.src);
  64                free(tracking.src);
  65                printf("Branch %s set up to track remote branch %s.\n",
  66                               new_ref, orig_ref);
  67        }
  68
  69        return 0;
  70}
  71
  72void create_branch(const char *head,
  73                   const char *name, const char *start_name,
  74                   int force, int reflog, int track)
  75{
  76        struct ref_lock *lock;
  77        struct commit *commit;
  78        unsigned char sha1[20];
  79        char *real_ref, ref[PATH_MAX], msg[PATH_MAX + 20];
  80        int forcing = 0;
  81
  82        snprintf(ref, sizeof ref, "refs/heads/%s", name);
  83        if (check_ref_format(ref))
  84                die("'%s' is not a valid branch name.", name);
  85
  86        if (resolve_ref(ref, sha1, 1, NULL)) {
  87                if (!force)
  88                        die("A branch named '%s' already exists.", name);
  89                else if (!is_bare_repository() && !strcmp(head, name))
  90                        die("Cannot force update the current branch.");
  91                forcing = 1;
  92        }
  93
  94        real_ref = NULL;
  95        if (get_sha1(start_name, sha1))
  96                die("Not a valid object name: '%s'.", start_name);
  97
  98        switch (dwim_ref(start_name, strlen(start_name), sha1, &real_ref)) {
  99        case 0:
 100                /* Not branching from any existing branch */
 101                real_ref = NULL;
 102                break;
 103        case 1:
 104                /* Unique completion -- good */
 105                break;
 106        default:
 107                die("Ambiguous object name: '%s'.", start_name);
 108                break;
 109        }
 110
 111        if ((commit = lookup_commit_reference(sha1)) == NULL)
 112                die("Not a valid branch point: '%s'.", start_name);
 113        hashcpy(sha1, commit->object.sha1);
 114
 115        lock = lock_any_ref_for_update(ref, NULL, 0);
 116        if (!lock)
 117                die("Failed to lock ref for update: %s.", strerror(errno));
 118
 119        if (reflog)
 120                log_all_ref_updates = 1;
 121
 122        if (forcing)
 123                snprintf(msg, sizeof msg, "branch: Reset from %s",
 124                         start_name);
 125        else
 126                snprintf(msg, sizeof msg, "branch: Created from %s",
 127                         start_name);
 128
 129        /* When branching off a remote branch, set up so that git-pull
 130           automatically merges from there.  So far, this is only done for
 131           remotes registered via .git/config.  */
 132        if (real_ref && track)
 133                setup_tracking(name, real_ref);
 134
 135        if (write_ref_sha1(lock, sha1, msg) < 0)
 136                die("Failed to write ref: %s.", strerror(errno));
 137
 138        if (real_ref)
 139                free(real_ref);
 140}