git/builtin/merge-base.c
Jonathan Nieder a1e0ad78b7 merge-base --independent to print reduced parent list in a merge
While show-branch --independent does not support more than MAX_REVS
revs, git internally supports more with a different algorithm.
Expose that functionality as "git merge-base --independent".

This should help scripts to catch up with builtin merge in supporting
dodecapus.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-08-18 14:02:03 -07:00

102 lines
2.3 KiB
C

#include "builtin.h"
#include "cache.h"
#include "commit.h"
#include "parse-options.h"
static int show_merge_base(struct commit **rev, int rev_nr, int show_all)
{
struct commit_list *result;
result = get_merge_bases_many(rev[0], rev_nr - 1, rev + 1, 0);
if (!result)
return 1;
while (result) {
printf("%s\n", sha1_to_hex(result->item->object.sha1));
if (!show_all)
return 0;
result = result->next;
}
return 0;
}
static const char * const merge_base_usage[] = {
"git merge-base [-a|--all] [--octopus] <commit> <commit>...",
"git merge-base --independent <commit>...",
NULL
};
static struct commit *get_commit_reference(const char *arg)
{
unsigned char revkey[20];
struct commit *r;
if (get_sha1(arg, revkey))
die("Not a valid object name %s", arg);
r = lookup_commit_reference(revkey);
if (!r)
die("Not a valid commit name %s", arg);
return r;
}
static int handle_octopus(int count, const char **args, int reduce, int show_all)
{
struct commit_list *revs = NULL;
struct commit_list *result;
int i;
if (reduce)
show_all = 1;
for (i = count - 1; i >= 0; i--)
commit_list_insert(get_commit_reference(args[i]), &revs);
result = reduce ? reduce_heads(revs) : get_octopus_merge_bases(revs);
if (!result)
return 1;
while (result) {
printf("%s\n", sha1_to_hex(result->item->object.sha1));
if (!show_all)
return 0;
result = result->next;
}
return 0;
}
int cmd_merge_base(int argc, const char **argv, const char *prefix)
{
struct commit **rev;
int rev_nr = 0;
int show_all = 0;
int octopus = 0;
int reduce = 0;
struct option options[] = {
OPT_BOOLEAN('a', "all", &show_all, "output all common ancestors"),
OPT_BOOLEAN(0, "octopus", &octopus, "find ancestors for a single n-way merge"),
OPT_BOOLEAN(0, "independent", &reduce, "list revs not reachable from others"),
OPT_END()
};
git_config(git_default_config, NULL);
argc = parse_options(argc, argv, prefix, options, merge_base_usage, 0);
if (!octopus && !reduce && argc < 2)
usage_with_options(merge_base_usage, options);
if (reduce && (show_all || octopus))
die("--independent cannot be used with other options");
if (octopus || reduce)
return handle_octopus(argc, argv, reduce, show_all);
rev = xmalloc(argc * sizeof(*rev));
while (argc-- > 0)
rev[rev_nr++] = get_commit_reference(*argv++);
return show_merge_base(rev, rev_nr, show_all);
}