branch.con commit git-bisect.sh: don't accidentally override existing branch "bisect" (ee831f7)
   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                          enum branch_track track)
  42{
  43        char key[1024];
  44        struct tracking tracking;
  45
  46        if (strlen(new_ref) > 1024 - 7 - 7 - 1)
  47                return error("Tracking not set up: name too long: %s",
  48                                new_ref);
  49
  50        memset(&tracking, 0, sizeof(tracking));
  51        tracking.spec.dst = (char *)orig_ref;
  52        if (for_each_remote(find_tracked_branch, &tracking))
  53                return 1;
  54
  55        if (!tracking.matches)
  56                switch (track) {
  57                case BRANCH_TRACK_ALWAYS:
  58                case BRANCH_TRACK_EXPLICIT:
  59                        break;
  60                default:
  61                        return 1;
  62                }
  63
  64        if (tracking.matches > 1)
  65                return error("Not tracking: ambiguous information for ref %s",
  66                                orig_ref);
  67
  68        sprintf(key, "branch.%s.remote", new_ref);
  69        git_config_set(key, tracking.remote ?  tracking.remote : ".");
  70        sprintf(key, "branch.%s.merge", new_ref);
  71        git_config_set(key, tracking.src ? tracking.src : orig_ref);
  72        free(tracking.src);
  73        printf("Branch %s set up to track %s branch %s.\n", new_ref,
  74                tracking.remote ? "remote" : "local", orig_ref);
  75
  76        return 0;
  77}
  78
  79void create_branch(const char *head,
  80                   const char *name, const char *start_name,
  81                   int force, int reflog, enum branch_track track)
  82{
  83        struct ref_lock *lock;
  84        struct commit *commit;
  85        unsigned char sha1[20];
  86        char *real_ref, ref[PATH_MAX], msg[PATH_MAX + 20];
  87        int forcing = 0;
  88
  89        snprintf(ref, sizeof ref, "refs/heads/%s", name);
  90        if (check_ref_format(ref))
  91                die("'%s' is not a valid branch name.", name);
  92
  93        if (resolve_ref(ref, sha1, 1, NULL)) {
  94                if (!force)
  95                        die("A branch named '%s' already exists.", name);
  96                else if (!is_bare_repository() && !strcmp(head, name))
  97                        die("Cannot force update the current branch.");
  98                forcing = 1;
  99        }
 100
 101        real_ref = NULL;
 102        if (get_sha1(start_name, sha1))
 103                die("Not a valid object name: '%s'.", start_name);
 104
 105        switch (dwim_ref(start_name, strlen(start_name), sha1, &real_ref)) {
 106        case 0:
 107                /* Not branching from any existing branch */
 108                if (track == BRANCH_TRACK_EXPLICIT)
 109                        die("Cannot setup tracking information; starting point is not a branch.");
 110                break;
 111        case 1:
 112                /* Unique completion -- good */
 113                break;
 114        default:
 115                die("Ambiguous object name: '%s'.", start_name);
 116                break;
 117        }
 118
 119        if ((commit = lookup_commit_reference(sha1)) == NULL)
 120                die("Not a valid branch point: '%s'.", start_name);
 121        hashcpy(sha1, commit->object.sha1);
 122
 123        lock = lock_any_ref_for_update(ref, NULL, 0);
 124        if (!lock)
 125                die("Failed to lock ref for update: %s.", strerror(errno));
 126
 127        if (reflog)
 128                log_all_ref_updates = 1;
 129
 130        if (forcing)
 131                snprintf(msg, sizeof msg, "branch: Reset from %s",
 132                         start_name);
 133        else
 134                snprintf(msg, sizeof msg, "branch: Created from %s",
 135                         start_name);
 136
 137        if (real_ref && track)
 138                setup_tracking(name, real_ref, track);
 139
 140        if (write_ref_sha1(lock, sha1, msg) < 0)
 141                die("Failed to write ref: %s.", strerror(errno));
 142
 143        free(real_ref);
 144}
 145
 146void remove_branch_state(void)
 147{
 148        unlink(git_path("MERGE_HEAD"));
 149        unlink(git_path("rr-cache/MERGE_RR"));
 150        unlink(git_path("MERGE_MSG"));
 151        unlink(git_path("SQUASH_MSG"));
 152}