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 #include "commit-reach.h"
  11
  12 static int show_merge_base(struct commit **rev, int rev_nr, int show_all)
  13 {
  14         struct commit_list *result, *r;
  15
  16         result = get_merge_bases_many_dirty(rev[0], rev_nr - 1, rev + 1);
  17
  18         if (!result)
  19                 return 1;
  20
  21         for (r = result; r; r = r->next) {
  22                 printf("%s\n", oid_to_hex(&r->item->object.oid));
  23                 if (!show_all)
  24                         break;
  25         }
  26
  27         free_commit_list(result);
  28         return 0;
  29 }
  30
  31 static const char * const merge_base_usage[] = {
  32         N_("git merge-base [-a | --all] <commit> <commit>..."),
  33         N_("git merge-base [-a | --all] --octopus <commit>..."),
  34         N_("git merge-base --independent <commit>..."),
  35         N_("git merge-base --is-ancestor <commit> <commit>"),
  36         N_("git merge-base --fork-point <ref> [<commit>]"),
  37         NULL
  38 };
  39
  40 static struct commit *get_commit_reference(const char *arg)
  41 {
  42         struct object_id revkey;
  43         struct commit *r;
  44
  45         if (get_oid(arg, &revkey))
  46                 die("Not a valid object name %s", arg);
  47         r = lookup_commit_reference(the_repository, &revkey);
  48         if (!r)
  49                 die("Not a valid commit name %s", arg);
  50
  51         return r;
  52 }
  53
  54 static int handle_independent(int count, const char **args)
  55 {
  56         struct commit_list *revs = NULL, *rev;
  57         int i;
  58
  59         for (i = count - 1; i >= 0; i--)
  60                 commit_list_insert(get_commit_reference(args[i]), &revs);
  61
  62         reduce_heads_replace(&revs);
  63
  64         if (!revs)
  65                 return 1;
  66
  67         for (rev = revs; rev; rev = rev->next)
  68                 printf("%s\n", oid_to_hex(&rev->item->object.oid));
  69
  70         free_commit_list(revs);
  71         return 0;
  72 }
  73
  74 static int handle_octopus(int count, const char **args, int show_all)
  75 {
  76         struct commit_list *revs = NULL;
  77         struct commit_list *result, *rev;
  78         int i;
  79
  80         for (i = count - 1; i >= 0; i--)
  81                 commit_list_insert(get_commit_reference(args[i]), &revs);
  82
  83         result = get_octopus_merge_bases(revs);
  84         free_commit_list(revs);
  85         reduce_heads_replace(&result);
  86
  87         if (!result)
  88                 return 1;
  89
  90         for (rev = result; rev; rev = rev->next) {
  91                 printf("%s\n", oid_to_hex(&rev->item->object.oid));
  92                 if (!show_all)
  93                         break;
  94         }
  95
  96         free_commit_list(result);
  97         return 0;
  98 }
  99
 100 static int handle_is_ancestor(int argc, const char **argv)
 101 {
 102         struct commit *one, *two;
 103
 104         if (argc != 2)
 105                 die("--is-ancestor takes exactly two commits");
 106         one = get_commit_reference(argv[0]);
 107         two = get_commit_reference(argv[1]);
 108         if (in_merge_bases(one, two))
 109                 return 0;
 110         else
 111                 return 1;
 112 }
 113
 114 static int handle_fork_point(int argc, const char **argv)
 115 {
 116         struct object_id oid;
 117         char *refname;
 118         struct commit *derived, *fork_point;
 119         const char *commitname;
 120
 121         switch (dwim_ref(argv[0], strlen(argv[0]), &oid, &refname)) {
 122         case 0:
 123                 die("No such ref: '%s'", argv[0]);
 124         case 1:
 125                 break; /* good */
 126         default:
 127                 die("Ambiguous refname: '%s'", argv[0]);
 128         }
 129
 130         commitname = (argc == 2) ? argv[1] : "HEAD";
 131         if (get_oid(commitname, &oid))
 132                 die("Not a valid object name: '%s'", commitname);
 133
 134         derived = lookup_commit_reference(the_repository, &oid);
 135
 136         fork_point = get_fork_point(refname, derived);
 137
 138         if (!fork_point)
 139                 return 1;
 140
 141         printf("%s\n", oid_to_hex(&fork_point->object.oid));
 142         return 0;
 143 }
 144
 145 int cmd_merge_base(int argc, const char **argv, const char *prefix)
 146 {
 147         struct commit **rev;
 148         int rev_nr = 0;
 149         int show_all = 0;
 150         int cmdmode = 0;
 151
 152         struct option options[] = {
 153                 OPT_BOOL('a', "all", &show_all, N_("output all common ancestors")),
 154                 OPT_CMDMODE(0, "octopus", &cmdmode,
 155                             N_("find ancestors for a single n-way merge"), 'o'),
 156                 OPT_CMDMODE(0, "independent", &cmdmode,
 157                             N_("list revs not reachable from others"), 'r'),
 158                 OPT_CMDMODE(0, "is-ancestor", &cmdmode,
 159                             N_("is the first one ancestor of the other?"), 'a'),
 160                 OPT_CMDMODE(0, "fork-point", &cmdmode,
 161                             N_("find where <commit> forked from reflog of <ref>"), 'f'),
 162                 OPT_END()
 163         };
 164
 165         git_config(git_default_config, NULL);
 166         argc = parse_options(argc, argv, prefix, options, merge_base_usage, 0);
 167
 168         if (cmdmode == 'a') {
 169                 if (argc < 2)
 170                         usage_with_options(merge_base_usage, options);
 171                 if (show_all)
 172                         die("--is-ancestor cannot be used with --all");
 173                 return handle_is_ancestor(argc, argv);
 174         }
 175
 176         if (cmdmode == 'r' && show_all)
 177                 die("--independent cannot be used with --all");
 178
 179         if (cmdmode == 'o')
 180                 return handle_octopus(argc, argv, show_all);
 181
 182         if (cmdmode == 'r')
 183                 return handle_independent(argc, argv);
 184
 185         if (cmdmode == 'f') {
 186                 if (argc < 1 || 2 < argc)
 187                         usage_with_options(merge_base_usage, options);
 188                 return handle_fork_point(argc, argv);
 189         }
 190
 191         if (argc < 2)
 192                 usage_with_options(merge_base_usage, options);
 193
 194         ALLOC_ARRAY(rev, argc);
 195         while (argc-- > 0)
 196                 rev[rev_nr++] = get_commit_reference(*argv++);
 197         return show_merge_base(rev, rev_nr, show_all);
 198 }