builtin/merge-base.c

   1 #include "builtin.h"
   2 #include "cache.h"
   3 #include "config.h"
   4 #include "commit.h"
   5 #include "refs.h"
   6 #include "diff.h"
   7 #include "revision.h"
   8 #include "parse-options.h"
   9 #include "repository.h"
  10
  11 static int show_merge_base(struct commit **rev, int rev_nr, int show_all)
  12 {
  13         struct commit_list *result, *r;
  14
  15         result = get_merge_bases_many_dirty(rev[0], rev_nr - 1, rev + 1);
  16
  17         if (!result)
  18                 return 1;
  19
  20         for (r = result; r; r = r->next) {
  21                 printf("%s\n", oid_to_hex(&r->item->object.oid));
  22                 if (!show_all)
  23                         break;
  24         }
  25
  26         free_commit_list(result);
  27         return 0;
  28 }
  29
  30 static const char * const merge_base_usage[] = {
  31         N_("git merge-base [-a | --all] <commit> <commit>..."),
  32         N_("git merge-base [-a | --all] --octopus <commit>..."),
  33         N_("git merge-base --independent <commit>..."),
  34         N_("git merge-base --is-ancestor <commit> <commit>"),
  35         N_("git merge-base --fork-point <ref> [<commit>]"),
  36         NULL
  37 };
  38
  39 static struct commit *get_commit_reference(const char *arg)
  40 {
  41         struct object_id revkey;
  42         struct commit *r;
  43
  44         if (get_oid(arg, &revkey))
  45                 die("Not a valid object name %s", arg);
  46         r = lookup_commit_reference(the_repository, &revkey);
  47         if (!r)
  48                 die("Not a valid commit name %s", arg);
  49
  50         return r;
  51 }
  52
  53 static int handle_independent(int count, const char **args)
  54 {
  55         struct commit_list *revs = NULL, *rev;
  56         int i;
  57
  58         for (i = count - 1; i >= 0; i--)
  59                 commit_list_insert(get_commit_reference(args[i]), &revs);
  60
  61         reduce_heads_replace(&revs);
  62
  63         if (!revs)
  64                 return 1;
  65
  66         for (rev = revs; rev; rev = rev->next)
  67                 printf("%s\n", oid_to_hex(&rev->item->object.oid));
  68
  69         free_commit_list(revs);
  70         return 0;
  71 }
  72
  73 static int handle_octopus(int count, const char **args, int show_all)
  74 {
  75         struct commit_list *revs = NULL;
  76         struct commit_list *result, *rev;
  77         int i;
  78
  79         for (i = count - 1; i >= 0; i--)
  80                 commit_list_insert(get_commit_reference(args[i]), &revs);
  81
  82         result = get_octopus_merge_bases(revs);
  83         free_commit_list(revs);
  84         reduce_heads_replace(&result);
  85
  86         if (!result)
  87                 return 1;
  88
  89         for (rev = result; rev; rev = rev->next) {
  90                 printf("%s\n", oid_to_hex(&rev->item->object.oid));
  91                 if (!show_all)
  92                         break;
  93         }
  94
  95         free_commit_list(result);
  96         return 0;
  97 }
  98
  99 static int handle_is_ancestor(int argc, const char **argv)
 100 {
 101         struct commit *one, *two;
 102
 103         if (argc != 2)
 104                 die("--is-ancestor takes exactly two commits");
 105         one = get_commit_reference(argv[0]);
 106         two = get_commit_reference(argv[1]);
 107         if (in_merge_bases(one, two))
 108                 return 0;
 109         else
 110                 return 1;
 111 }
 112
 113 static int handle_fork_point(int argc, const char **argv)
 114 {
 115         struct object_id oid;
 116         char *refname;
 117         struct commit *derived, *fork_point;
 118         const char *commitname;
 119
 120         switch (dwim_ref(argv[0], strlen(argv[0]), &oid, &refname)) {
 121         case 0:
 122                 die("No such ref: '%s'", argv[0]);
 123         case 1:
 124                 break; /* good */
 125         default:
 126                 die("Ambiguous refname: '%s'", argv[0]);
 127         }
 128
 129         commitname = (argc == 2) ? argv[1] : "HEAD";
 130         if (get_oid(commitname, &oid))
 131                 die("Not a valid object name: '%s'", commitname);
 132
 133         derived = lookup_commit_reference(the_repository, &oid);
 134
 135         fork_point = get_fork_point(refname, derived);
 136
 137         if (!fork_point)
 138                 return 1;
 139
 140         printf("%s\n", oid_to_hex(&fork_point->object.oid));
 141         return 0;
 142 }
 143
 144 int cmd_merge_base(int argc, const char **argv, const char *prefix)
 145 {
 146         struct commit **rev;
 147         int rev_nr = 0;
 148         int show_all = 0;
 149         int cmdmode = 0;
 150
 151         struct option options[] = {
 152                 OPT_BOOL('a', "all", &show_all, N_("output all common ancestors")),
 153                 OPT_CMDMODE(0, "octopus", &cmdmode,
 154                             N_("find ancestors for a single n-way merge"), 'o'),
 155                 OPT_CMDMODE(0, "independent", &cmdmode,
 156                             N_("list revs not reachable from others"), 'r'),
 157                 OPT_CMDMODE(0, "is-ancestor", &cmdmode,
 158                             N_("is the first one ancestor of the other?"), 'a'),
 159                 OPT_CMDMODE(0, "fork-point", &cmdmode,
 160                             N_("find where <commit> forked from reflog of <ref>"), 'f'),
 161                 OPT_END()
 162         };
 163
 164         git_config(git_default_config, NULL);
 165         argc = parse_options(argc, argv, prefix, options, merge_base_usage, 0);
 166
 167         if (cmdmode == 'a') {
 168                 if (argc < 2)
 169                         usage_with_options(merge_base_usage, options);
 170                 if (show_all)
 171                         die("--is-ancestor cannot be used with --all");
 172                 return handle_is_ancestor(argc, argv);
 173         }
 174
 175         if (cmdmode == 'r' && show_all)
 176                 die("--independent cannot be used with --all");
 177
 178         if (cmdmode == 'o')
 179                 return handle_octopus(argc, argv, show_all);
 180
 181         if (cmdmode == 'r')
 182                 return handle_independent(argc, argv);
 183
 184         if (cmdmode == 'f') {
 185                 if (argc < 1 || 2 < argc)
 186                         usage_with_options(merge_base_usage, options);
 187                 return handle_fork_point(argc, argv);
 188         }
 189
 190         if (argc < 2)
 191                 usage_with_options(merge_base_usage, options);
 192
 193         ALLOC_ARRAY(rev, argc);
 194         while (argc-- > 0)
 195                 rev[rev_nr++] = get_commit_reference(*argv++);
 196         return show_merge_base(rev, rev_nr, show_all);
 197 }