builtin-branch.c

   1 /*
   2  * Builtin "git branch"
   3  *
   4  * Copyright (c) 2006 Kristian Høgsberg <krh@redhat.com>
   5  * Based on git-branch.sh by Junio C Hamano.
   6  */
   7
   8 #include "cache.h"
   9 #include "refs.h"
  10 #include "commit.h"
  11 #include "builtin.h"
  12
  13 static const char builtin_branch_usage[] =
  14 "git-branch (-d | -D) <branchname> | [-l] [-f] <branchname> [<start-point>] | [-r] | [-a]";
  15
  16
  17 static const char *head;
  18 static unsigned char head_sha1[20];
  19
  20 static int in_merge_bases(const unsigned char *sha1,
  21                           struct commit *rev1,
  22                           struct commit *rev2)
  23 {
  24         struct commit_list *bases, *b;
  25         int ret = 0;
  26
  27         bases = get_merge_bases(rev1, rev2, 1);
  28         for (b = bases; b; b = b->next) {
  29                 if (!hashcmp(sha1, b->item->object.sha1)) {
  30                         ret = 1;
  31                         break;
  32                 }
  33         }
  34
  35         free_commit_list(bases);
  36         return ret;
  37 }
  38
  39 static void delete_branches(int argc, const char **argv, int force)
  40 {
  41         struct commit *rev, *head_rev;
  42         unsigned char sha1[20];
  43         char *name;
  44         int i;
  45
  46         head_rev = lookup_commit_reference(head_sha1);
  47         for (i = 0; i < argc; i++) {
  48                 if (!strcmp(head, argv[i]))
  49                         die("Cannot delete the branch you are currently on.");
  50
  51                 name = xstrdup(mkpath("refs/heads/%s", argv[i]));
  52                 if (!resolve_ref(name, sha1, 1, NULL))
  53                         die("Branch '%s' not found.", argv[i]);
  54
  55                 rev = lookup_commit_reference(sha1);
  56                 if (!rev || !head_rev)
  57                         die("Couldn't look up commit objects.");
  58
  59                 /* This checks whether the merge bases of branch and
  60                  * HEAD contains branch -- which means that the HEAD
  61                  * contains everything in both.
  62                  */
  63
  64                 if (!force &&
  65                     !in_merge_bases(sha1, rev, head_rev)) {
  66                         fprintf(stderr,
  67                                 "The branch '%s' is not a strict subset of your current HEAD.\n"
  68                                 "If you are sure you want to delete it, run 'git branch -D %s'.\n",
  69                                 argv[i], argv[i]);
  70                         exit(1);
  71                 }
  72
  73                 if (delete_ref(name, sha1))
  74                         printf("Error deleting branch '%s'\n", argv[i]);
  75                 else
  76                         printf("Deleted branch %s.\n", argv[i]);
  77
  78                 free(name);
  79         }
  80 }
  81
  82 #define REF_UNKNOWN_TYPE    0x00
  83 #define REF_LOCAL_BRANCH    0x01
  84 #define REF_REMOTE_BRANCH   0x02
  85 #define REF_TAG             0x04
  86
  87 struct ref_item {
  88         char *name;
  89         unsigned int kind;
  90 };
  91
  92 struct ref_list {
  93         int index, alloc;
  94         struct ref_item *list;
  95         int kinds;
  96 };
  97
  98 static int append_ref(const char *refname, const unsigned char *sha1, int flags, void *cb_data)
  99 {
 100         struct ref_list *ref_list = (struct ref_list*)(cb_data);
 101         struct ref_item *newitem;
 102         int kind = REF_UNKNOWN_TYPE;
 103
 104         /* Detect kind */
 105         if (!strncmp(refname, "refs/heads/", 11)) {
 106                 kind = REF_LOCAL_BRANCH;
 107                 refname += 11;
 108         } else if (!strncmp(refname, "refs/remotes/", 13)) {
 109                 kind = REF_REMOTE_BRANCH;
 110                 refname += 13;
 111         } else if (!strncmp(refname, "refs/tags/", 10)) {
 112                 kind = REF_TAG;
 113                 refname += 10;
 114         }
 115
 116         /* Don't add types the caller doesn't want */
 117         if ((kind & ref_list->kinds) == 0)
 118                 return 0;
 119
 120         /* Resize buffer */
 121         if (ref_list->index >= ref_list->alloc) {
 122                 ref_list->alloc = alloc_nr(ref_list->alloc);
 123                 ref_list->list = xrealloc(ref_list->list,
 124                                 ref_list->alloc * sizeof(struct ref_item));
 125         }
 126
 127         /* Record the new item */
 128         newitem = &(ref_list->list[ref_list->index++]);
 129         newitem->name = xstrdup(refname);
 130         newitem->kind = kind;
 131
 132         return 0;
 133 }
 134
 135 static void free_ref_list(struct ref_list *ref_list)
 136 {
 137         int i;
 138
 139         for (i = 0; i < ref_list->index; i++)
 140                 free(ref_list->list[i].name);
 141         free(ref_list->list);
 142 }
 143
 144 static int ref_cmp(const void *r1, const void *r2)
 145 {
 146         struct ref_item *c1 = (struct ref_item *)(r1);
 147         struct ref_item *c2 = (struct ref_item *)(r2);
 148
 149         if (c1->kind != c2->kind)
 150                 return c1->kind - c2->kind;
 151         return strcmp(c1->name, c2->name);
 152 }
 153
 154 static void print_ref_list(int kinds)
 155 {
 156         int i;
 157         char c;
 158         struct ref_list ref_list;
 159
 160         memset(&ref_list, 0, sizeof(ref_list));
 161         ref_list.kinds = kinds;
 162         for_each_ref(append_ref, &ref_list);
 163
 164         qsort(ref_list.list, ref_list.index, sizeof(struct ref_item), ref_cmp);
 165
 166         for (i = 0; i < ref_list.index; i++) {
 167                 c = ' ';
 168                 if (ref_list.list[i].kind == REF_LOCAL_BRANCH &&
 169                                 !strcmp(ref_list.list[i].name, head))
 170                         c = '*';
 171
 172                 printf("%c %s\n", c, ref_list.list[i].name);
 173         }
 174
 175         free_ref_list(&ref_list);
 176 }
 177
 178 static void create_branch(const char *name, const char *start,
 179                           int force, int reflog)
 180 {
 181         struct ref_lock *lock;
 182         struct commit *commit;
 183         unsigned char sha1[20];
 184         char ref[PATH_MAX], msg[PATH_MAX + 20];
 185
 186         snprintf(ref, sizeof ref, "refs/heads/%s", name);
 187         if (check_ref_format(ref))
 188                 die("'%s' is not a valid branch name.", name);
 189
 190         if (resolve_ref(ref, sha1, 1, NULL)) {
 191                 if (!force)
 192                         die("A branch named '%s' already exists.", name);
 193                 else if (!strcmp(head, name))
 194                         die("Cannot force update the current branch.");
 195         }
 196
 197         if (get_sha1(start, sha1) ||
 198             (commit = lookup_commit_reference(sha1)) == NULL)
 199                 die("Not a valid branch point: '%s'.", start);
 200         hashcpy(sha1, commit->object.sha1);
 201
 202         lock = lock_any_ref_for_update(ref, NULL);
 203         if (!lock)
 204                 die("Failed to lock ref for update: %s.", strerror(errno));
 205
 206         if (reflog) {
 207                 log_all_ref_updates = 1;
 208                 snprintf(msg, sizeof msg, "branch: Created from %s", start);
 209         }
 210
 211         if (write_ref_sha1(lock, sha1, msg) < 0)
 212                 die("Failed to write ref: %s.", strerror(errno));
 213 }
 214
 215 int cmd_branch(int argc, const char **argv, const char *prefix)
 216 {
 217         int delete = 0, force_delete = 0, force_create = 0;
 218         int reflog = 0;
 219         int kinds = REF_LOCAL_BRANCH;
 220         int i;
 221
 222         git_config(git_default_config);
 223
 224         for (i = 1; i < argc; i++) {
 225                 const char *arg = argv[i];
 226
 227                 if (arg[0] != '-')
 228                         break;
 229                 if (!strcmp(arg, "--")) {
 230                         i++;
 231                         break;
 232                 }
 233                 if (!strcmp(arg, "-d")) {
 234                         delete = 1;
 235                         continue;
 236                 }
 237                 if (!strcmp(arg, "-D")) {
 238                         delete = 1;
 239                         force_delete = 1;
 240                         continue;
 241                 }
 242                 if (!strcmp(arg, "-f")) {
 243                         force_create = 1;
 244                         continue;
 245                 }
 246                 if (!strcmp(arg, "-r")) {
 247                         kinds = REF_REMOTE_BRANCH;
 248                         continue;
 249                 }
 250                 if (!strcmp(arg, "-a")) {
 251                         kinds = REF_REMOTE_BRANCH | REF_LOCAL_BRANCH;
 252                         continue;
 253                 }
 254                 if (!strcmp(arg, "-l")) {
 255                         reflog = 1;
 256                         continue;
 257                 }
 258                 usage(builtin_branch_usage);
 259         }
 260
 261         head = xstrdup(resolve_ref("HEAD", head_sha1, 0, NULL));
 262         if (!head)
 263                 die("Failed to resolve HEAD as a valid ref.");
 264         if (strncmp(head, "refs/heads/", 11))
 265                 die("HEAD not found below refs/heads!");
 266         head += 11;
 267
 268         if (delete)
 269                 delete_branches(argc - i, argv + i, force_delete);
 270         else if (i == argc)
 271                 print_ref_list(kinds);
 272         else if (i == argc - 1)
 273                 create_branch(argv[i], head, force_create, reflog);
 274         else if (i == argc - 2)
 275                 create_branch(argv[i], argv[i + 1], force_create, reflog);
 276         else
 277                 usage(builtin_branch_usage);
 278
 279         return 0;
 280 }