Andrew's git - gitweb.git/blob - builtin/merge-base.c

   1#include "builtin.h"
   2#include "cache.h"
   3#include "commit.h"
   4#include "parse-options.h"
   5
   6static int show_merge_base(struct commit **rev, int rev_nr, int show_all)
   7{
   8        struct commit_list *result;
   9
  10        result = get_merge_bases_many(rev[0], rev_nr - 1, rev + 1, 0);
  11
  12        if (!result)
  13                return 1;
  14
  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;
  20        }
  21
  22        return 0;
  23}
  24
  25static const char * const merge_base_usage[] = {
  26        N_("git merge-base [-a|--all] <commit> <commit>..."),
  27        N_("git merge-base [-a|--all] --octopus <commit>..."),
  28        N_("git merge-base --independent <commit>..."),
  29        N_("git merge-base --is-ancestor <commit> <commit>"),
  30        NULL
  31};
  32
  33static struct commit *get_commit_reference(const char *arg)
  34{
  35        unsigned char revkey[20];
  36        struct commit *r;
  37
  38        if (get_sha1(arg, revkey))
  39                die("Not a valid object name %s", arg);
  40        r = lookup_commit_reference(revkey);
  41        if (!r)
  42                die("Not a valid commit name %s", arg);
  43
  44        return r;
  45}
  46
  47static int handle_octopus(int count, const char **args, int reduce, int show_all)
  48{
  49        struct commit_list *revs = NULL;
  50        struct commit_list *result;
  51        int i;
  52
  53        if (reduce)
  54                show_all = 1;
  55
  56        for (i = count - 1; i >= 0; i--)
  57                commit_list_insert(get_commit_reference(args[i]), &revs);
  58
  59        result = reduce ? reduce_heads(revs) : get_octopus_merge_bases(revs);
  60
  61        if (!result)
  62                return 1;
  63
  64        while (result) {
  65                printf("%s\n", sha1_to_hex(result->item->object.sha1));
  66                if (!show_all)
  67                        return 0;
  68                result = result->next;
  69        }
  70
  71        return 0;
  72}
  73
  74static int handle_is_ancestor(int argc, const char **argv)
  75{
  76        struct commit *one, *two;
  77
  78        if (argc != 2)
  79                die("--is-ancestor takes exactly two commits");
  80        one = get_commit_reference(argv[0]);
  81        two = get_commit_reference(argv[1]);
  82        if (in_merge_bases(one, two))
  83                return 0;
  84        else
  85                return 1;
  86}
  87
  88int cmd_merge_base(int argc, const char **argv, const char *prefix)
  89{
  90        struct commit **rev;
  91        int rev_nr = 0;
  92        int show_all = 0;
  93        int octopus = 0;
  94        int reduce = 0;
  95        int is_ancestor = 0;
  96
  97        struct option options[] = {
  98                OPT_BOOL('a', "all", &show_all, N_("output all common ancestors")),
  99                OPT_BOOL(0, "octopus", &octopus, N_("find ancestors for a single n-way merge")),
 100                OPT_BOOL(0, "independent", &reduce, N_("list revs not reachable from others")),
 101                OPT_BOOL(0, "is-ancestor", &is_ancestor,
 102                         N_("is the first one ancestor of the other?")),
 103                OPT_END()
 104        };
 105
 106        git_config(git_default_config, NULL);
 107        argc = parse_options(argc, argv, prefix, options, merge_base_usage, 0);
 108        if (!octopus && !reduce && argc < 2)
 109                usage_with_options(merge_base_usage, options);
 110        if (is_ancestor && (show_all || octopus || reduce))
 111                die("--is-ancestor cannot be used with other options");
 112        if (is_ancestor)
 113                return handle_is_ancestor(argc, argv);
 114        if (reduce && (show_all || octopus))
 115                die("--independent cannot be used with other options");
 116
 117        if (octopus || reduce)
 118                return handle_octopus(argc, argv, reduce, show_all);
 119
 120        rev = xmalloc(argc * sizeof(*rev));
 121        while (argc-- > 0)
 122                rev[rev_nr++] = get_commit_reference(*argv++);
 123        return show_merge_base(rev, rev_nr, show_all);
 124}