示例#1
0
文件: revert.c 项目: jjuran/git
static int do_pick_commit(void)
{
	unsigned char head[20];
	struct commit *base, *next, *parent;
	const char *base_label, *next_label;
	struct commit_message msg = { NULL, NULL, NULL, NULL, NULL };
	char *defmsg = NULL;
	struct strbuf msgbuf = STRBUF_INIT;
	int res;

	if (no_commit) {
		/*
		 * We do not intend to commit immediately.  We just want to
		 * merge the differences in, so let's compute the tree
		 * that represents the "current" state for merge-recursive
		 * to work on.
		 */
		if (write_cache_as_tree(head, 0, NULL))
			die (_("Your index file is unmerged."));
	} else {
		if (get_sha1("HEAD", head))
			die (_("You do not have a valid HEAD"));
		if (index_differs_from("HEAD", 0))
			die_dirty_index(me);
	}
	discard_cache();

	if (!commit->parents) {
		parent = NULL;
	}
	else if (commit->parents->next) {
		/* Reverting or cherry-picking a merge commit */
		int cnt;
		struct commit_list *p;

		if (!mainline)
			die(_("Commit %s is a merge but no -m option was given."),
			    sha1_to_hex(commit->object.sha1));

		for (cnt = 1, p = commit->parents;
		     cnt != mainline && p;
		     cnt++)
			p = p->next;
		if (cnt != mainline || !p)
			die(_("Commit %s does not have parent %d"),
			    sha1_to_hex(commit->object.sha1), mainline);
		parent = p->item;
	} else if (0 < mainline)
		die(_("Mainline was specified but commit %s is not a merge."),
		    sha1_to_hex(commit->object.sha1));
	else
		parent = commit->parents->item;

	if (allow_ff && parent && !hashcmp(parent->object.sha1, head))
		return fast_forward_to(commit->object.sha1, head);

	if (parent && parse_commit(parent) < 0)
		/* TRANSLATORS: The first %s will be "revert" or
		   "cherry-pick", the second %s a SHA1 */
		die(_("%s: cannot parse parent commit %s"),
		    me, sha1_to_hex(parent->object.sha1));

	if (get_message(commit->buffer, &msg) != 0)
		die(_("Cannot get commit message for %s"),
				sha1_to_hex(commit->object.sha1));

	/*
	 * "commit" is an existing commit.  We would want to apply
	 * the difference it introduces since its first parent "prev"
	 * on top of the current HEAD if we are cherry-pick.  Or the
	 * reverse of it if we are revert.
	 */

	defmsg = git_pathdup("MERGE_MSG");

	if (action == REVERT) {
		base = commit;
		base_label = msg.label;
		next = parent;
		next_label = msg.parent_label;
		strbuf_addstr(&msgbuf, "Revert \"");
		strbuf_addstr(&msgbuf, msg.subject);
		strbuf_addstr(&msgbuf, "\"\n\nThis reverts commit ");
		strbuf_addstr(&msgbuf, sha1_to_hex(commit->object.sha1));

		if (commit->parents && commit->parents->next) {
			strbuf_addstr(&msgbuf, ", reversing\nchanges made to ");
			strbuf_addstr(&msgbuf, sha1_to_hex(parent->object.sha1));
		}
		strbuf_addstr(&msgbuf, ".\n");
	} else {
		base = parent;
		base_label = msg.parent_label;
		next = commit;
		next_label = msg.label;
		add_message_to_msg(&msgbuf, msg.message);
		if (no_replay) {
			strbuf_addstr(&msgbuf, "(cherry picked from commit ");
			strbuf_addstr(&msgbuf, sha1_to_hex(commit->object.sha1));
			strbuf_addstr(&msgbuf, ")\n");
		}
		if (!no_commit)
			write_cherry_pick_head();
	}

	if (!strategy || !strcmp(strategy, "recursive") || action == REVERT) {
		res = do_recursive_merge(base, next, base_label, next_label,
					 head, &msgbuf);
		write_message(&msgbuf, defmsg);
	} else {
		struct commit_list *common = NULL;
		struct commit_list *remotes = NULL;

		write_message(&msgbuf, defmsg);

		commit_list_insert(base, &common);
		commit_list_insert(next, &remotes);
		res = try_merge_command(strategy, xopts_nr, xopts, common,
					sha1_to_hex(head), remotes);
		free_commit_list(common);
		free_commit_list(remotes);
	}

	if (res) {
		error(action == REVERT
		      ? _("could not revert %s... %s")
		      : _("could not apply %s... %s"),
		      find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV),
		      msg.subject);
		print_advice();
		rerere(allow_rerere_auto);
	} else {
		if (!no_commit)
			res = run_git_commit(defmsg);
	}

	free_message(&msg);
	free(defmsg);

	return res;
}