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]";
  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 static int ref_index, ref_alloc;
  83 static char **ref_list;
  84
  85 static int append_ref(const char *refname, const unsigned char *sha1, int flags,
  86                 void *cb_data)
  87 {
  88         if (ref_index >= ref_alloc) {
  89                 ref_alloc = alloc_nr(ref_alloc);
  90                 ref_list = xrealloc(ref_list, ref_alloc * sizeof(char *));
  91         }
  92
  93         ref_list[ref_index++] = xstrdup(refname);
  94
  95         return 0;
  96 }
  97
  98 static int ref_cmp(const void *r1, const void *r2)
  99 {
 100         return strcmp(*(char **)r1, *(char **)r2);
 101 }
 102
 103 static void print_ref_list(int remote_only)
 104 {
 105         int i;
 106         char c;
 107
 108         if (remote_only)
 109                 for_each_remote_ref(append_ref, NULL);
 110         else
 111                 for_each_branch_ref(append_ref, NULL);
 112
 113         qsort(ref_list, ref_index, sizeof(char *), ref_cmp);
 114
 115         for (i = 0; i < ref_index; i++) {
 116                 c = ' ';
 117                 if (!strcmp(ref_list[i], head))
 118                         c = '*';
 119
 120                 printf("%c %s\n", c, ref_list[i]);
 121         }
 122 }
 123
 124 static void create_branch(const char *name, const char *start,
 125                           int force, int reflog)
 126 {
 127         struct ref_lock *lock;
 128         struct commit *commit;
 129         unsigned char sha1[20];
 130         char ref[PATH_MAX], msg[PATH_MAX + 20];
 131
 132         snprintf(ref, sizeof ref, "refs/heads/%s", name);
 133         if (check_ref_format(ref))
 134                 die("'%s' is not a valid branch name.", name);
 135
 136         if (resolve_ref(ref, sha1, 1, NULL)) {
 137                 if (!force)
 138                         die("A branch named '%s' already exists.", name);
 139                 else if (!strcmp(head, name))
 140                         die("Cannot force update the current branch.");
 141         }
 142
 143         if (get_sha1(start, sha1) ||
 144             (commit = lookup_commit_reference(sha1)) == NULL)
 145                 die("Not a valid branch point: '%s'.", start);
 146         hashcpy(sha1, commit->object.sha1);
 147
 148         lock = lock_any_ref_for_update(ref, NULL);
 149         if (!lock)
 150                 die("Failed to lock ref for update: %s.", strerror(errno));
 151
 152         if (reflog) {
 153                 log_all_ref_updates = 1;
 154                 snprintf(msg, sizeof msg, "branch: Created from %s", start);
 155         }
 156
 157         if (write_ref_sha1(lock, sha1, msg) < 0)
 158                 die("Failed to write ref: %s.", strerror(errno));
 159 }
 160
 161 int cmd_branch(int argc, const char **argv, const char *prefix)
 162 {
 163         int delete = 0, force_delete = 0, force_create = 0, remote_only = 0;
 164         int reflog = 0;
 165         int i;
 166
 167         git_config(git_default_config);
 168
 169         for (i = 1; i < argc; i++) {
 170                 const char *arg = argv[i];
 171
 172                 if (arg[0] != '-')
 173                         break;
 174                 if (!strcmp(arg, "--")) {
 175                         i++;
 176                         break;
 177                 }
 178                 if (!strcmp(arg, "-d")) {
 179                         delete = 1;
 180                         continue;
 181                 }
 182                 if (!strcmp(arg, "-D")) {
 183                         delete = 1;
 184                         force_delete = 1;
 185                         continue;
 186                 }
 187                 if (!strcmp(arg, "-f")) {
 188                         force_create = 1;
 189                         continue;
 190                 }
 191                 if (!strcmp(arg, "-r")) {
 192                         remote_only = 1;
 193                         continue;
 194                 }
 195                 if (!strcmp(arg, "-l")) {
 196                         reflog = 1;
 197                         continue;
 198                 }
 199                 usage(builtin_branch_usage);
 200         }
 201
 202         head = xstrdup(resolve_ref("HEAD", head_sha1, 0, NULL));
 203         if (!head)
 204                 die("Failed to resolve HEAD as a valid ref.");
 205         if (strncmp(head, "refs/heads/", 11))
 206                 die("HEAD not found below refs/heads!");
 207         head += 11;
 208
 209         if (delete)
 210                 delete_branches(argc - i, argv + i, force_delete);
 211         else if (i == argc)
 212                 print_ref_list(remote_only);
 213         else if (i == argc - 1)
 214                 create_branch(argv[i], head, force_create, reflog);
 215         else if (i == argc - 2)
 216                 create_branch(argv[i], argv[i + 1], force_create, reflog);
 217         else
 218                 usage(builtin_branch_usage);
 219
 220         return 0;
 221 }