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#include "builtin.h"
#include "cache.h"
#include "commit.h"
#include "refs.h"
#include "diff.h"
#include "revision.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[] = {
N_("git merge-base [-a|--all] <commit> <commit>..."),
N_("git merge-base [-a|--all] --octopus <commit>..."),
N_("git merge-base --independent <commit>..."),
N_("git merge-base --is-ancestor <commit> <commit>"),
N_("git merge-base --fork-point <ref> [<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;
}
static int handle_is_ancestor(int argc, const char **argv)
{
struct commit *one, *two;
if (argc != 2)
die("--is-ancestor takes exactly two commits");
one = get_commit_reference(argv[0]);
two = get_commit_reference(argv[1]);
if (in_merge_bases(one, two))
return 0;
else
return 1;
}
struct rev_collect {
struct commit **commit;
int nr;
int alloc;
unsigned int initial : 1;
};
static void add_one_commit(unsigned char *sha1, struct rev_collect *revs)
{
struct commit *commit;
if (is_null_sha1(sha1))
return;
commit = lookup_commit(sha1);
if (!commit ||
(commit->object.flags & TMP_MARK) ||
parse_commit(commit))
return;
ALLOC_GROW(revs->commit, revs->nr + 1, revs->alloc);
revs->commit[revs->nr++] = commit;
commit->object.flags |= TMP_MARK;
}
static int collect_one_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
const char *ident, unsigned long timestamp,
int tz, const char *message, void *cbdata)
{
struct rev_collect *revs = cbdata;
if (revs->initial) {
revs->initial = 0;
add_one_commit(osha1, revs);
}
add_one_commit(nsha1, revs);
return 0;
}
static int handle_fork_point(int argc, const char **argv)
{
unsigned char sha1[20];
char *refname;
const char *commitname;
struct rev_collect revs;
struct commit *derived;
struct commit_list *bases;
int i, ret = 0;
switch (dwim_ref(argv[0], strlen(argv[0]), sha1, &refname)) {
case 0:
die("No such ref: '%s'", argv[0]);
case 1:
break; /* good */
default:
die("Ambiguous refname: '%s'", argv[0]);
}
commitname = (argc == 2) ? argv[1] : "HEAD";
if (get_sha1(commitname, sha1))
die("Not a valid object name: '%s'", commitname);
derived = lookup_commit_reference(sha1);
memset(&revs, 0, sizeof(revs));
revs.initial = 1;
for_each_reflog_ent(refname, collect_one_reflog_ent, &revs);
for (i = 0; i < revs.nr; i++)
revs.commit[i]->object.flags &= ~TMP_MARK;
bases = get_merge_bases_many(derived, revs.nr, revs.commit, 0);
/*
* There should be one and only one merge base, when we found
* a common ancestor among reflog entries.
*/
if (!bases || bases->next) {
ret = 1;
goto cleanup_return;
}
/* And the found one must be one of the reflog entries */
for (i = 0; i < revs.nr; i++)
if (&bases->item->object == &revs.commit[i]->object)
break; /* found */
if (revs.nr <= i) {
ret = 1; /* not found */
goto cleanup_return;
}
printf("%s\n", sha1_to_hex(bases->item->object.sha1));
cleanup_return:
free_commit_list(bases);
return ret;
}
int cmd_merge_base(int argc, const char **argv, const char *prefix)
{
struct commit **rev;
int rev_nr = 0;
int show_all = 0;
int cmdmode = 0;
struct option options[] = {
OPT_BOOL('a', "all", &show_all, N_("output all common ancestors")),
OPT_CMDMODE(0, "octopus", &cmdmode,
N_("find ancestors for a single n-way merge"), 'o'),
OPT_CMDMODE(0, "independent", &cmdmode,
N_("list revs not reachable from others"), 'r'),
OPT_CMDMODE(0, "is-ancestor", &cmdmode,
N_("is the first one ancestor of the other?"), 'a'),
OPT_CMDMODE(0, "fork-point", &cmdmode,
N_("find where <commit> forked from reflog of <ref>"), 'f'),
OPT_END()
};
git_config(git_default_config, NULL);
argc = parse_options(argc, argv, prefix, options, merge_base_usage, 0);
if (cmdmode == 'a') {
if (argc < 2)
usage_with_options(merge_base_usage, options);
if (show_all)
die("--is-ancestor cannot be used with --all");
return handle_is_ancestor(argc, argv);
}
if (cmdmode == 'r' && show_all)
die("--independent cannot be used with --all");
if (cmdmode == 'r' || cmdmode == 'o')
return handle_octopus(argc, argv, cmdmode == 'r', show_all);
if (cmdmode == 'f') {
if (argc < 1 || 2 < argc)
usage_with_options(merge_base_usage, options);
return handle_fork_point(argc, argv);
}
if (argc < 2)
usage_with_options(merge_base_usage, options);
rev = xmalloc(argc * sizeof(*rev));
while (argc-- > 0)
rev[rev_nr++] = get_commit_reference(*argv++);
return show_merge_base(rev, rev_nr, show_all);
}
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