Merge branch 'cb/maint-orphan-merge-noclobber'
[git/kirr.git] / builtin / merge-base.c
blob96dd160731ce29b18be646893057929bab97cb8a
1 #include "builtin.h"
2 #include "cache.h"
3 #include "commit.h"
4 #include "parse-options.h"
6 static int show_merge_base(struct commit **rev, int rev_nr, int show_all)
8 struct commit_list *result;
10 result = get_merge_bases_many(rev[0], rev_nr - 1, rev + 1, 0);
12 if (!result)
13 return 1;
15 while (result) {
16 printf("%s\n", sha1_to_hex(result->item->object.sha1));
17 if (!show_all)
18 return 0;
19 result = result->next;
22 return 0;
25 static const char * const merge_base_usage[] = {
26 "git merge-base [-a|--all] [--octopus] <commit> <commit>...",
27 "git merge-base --independent <commit>...",
28 NULL
31 static struct commit *get_commit_reference(const char *arg)
33 unsigned char revkey[20];
34 struct commit *r;
36 if (get_sha1(arg, revkey))
37 die("Not a valid object name %s", arg);
38 r = lookup_commit_reference(revkey);
39 if (!r)
40 die("Not a valid commit name %s", arg);
42 return r;
45 static int handle_octopus(int count, const char **args, int reduce, int show_all)
47 struct commit_list *revs = NULL;
48 struct commit_list *result;
49 int i;
51 if (reduce)
52 show_all = 1;
54 for (i = count - 1; i >= 0; i--)
55 commit_list_insert(get_commit_reference(args[i]), &revs);
57 result = reduce ? reduce_heads(revs) : get_octopus_merge_bases(revs);
59 if (!result)
60 return 1;
62 while (result) {
63 printf("%s\n", sha1_to_hex(result->item->object.sha1));
64 if (!show_all)
65 return 0;
66 result = result->next;
69 return 0;
72 int cmd_merge_base(int argc, const char **argv, const char *prefix)
74 struct commit **rev;
75 int rev_nr = 0;
76 int show_all = 0;
77 int octopus = 0;
78 int reduce = 0;
80 struct option options[] = {
81 OPT_BOOLEAN('a', "all", &show_all, "output all common ancestors"),
82 OPT_BOOLEAN(0, "octopus", &octopus, "find ancestors for a single n-way merge"),
83 OPT_BOOLEAN(0, "independent", &reduce, "list revs not reachable from others"),
84 OPT_END()
87 git_config(git_default_config, NULL);
88 argc = parse_options(argc, argv, prefix, options, merge_base_usage, 0);
89 if (!octopus && !reduce && argc < 2)
90 usage_with_options(merge_base_usage, options);
91 if (reduce && (show_all || octopus))
92 die("--independent cannot be used with other options");
94 if (octopus || reduce)
95 return handle_octopus(argc, argv, reduce, show_all);
97 rev = xmalloc(argc * sizeof(*rev));
98 while (argc-- > 0)
99 rev[rev_nr++] = get_commit_reference(*argv++);
100 return show_merge_base(rev, rev_nr, show_all);