git/connected.c

#include "cache.h"
#include "run-command.h"
#include "sigchain.h"
#include "connected.h"
#include "transport.h"

int check_everything_connected(sha1_iterate_fn fn, int quiet, void *cb_data)
{
	return check_everything_connected_with_transport(fn, quiet, cb_data, NULL);
}
/*
 * If we feed all the commits we want to verify to this command
 *
 *  $ git rev-list --objects --stdin --not --all
 *
 * and if it does not error out, that means everything reachable from
 * these commits locally exists and is connected to our existing refs.
 * Note that this does _not_ validate the individual objects.
 *
 * Returns 0 if everything is connected, non-zero otherwise.
 */
int check_everything_connected_with_transport(sha1_iterate_fn fn,
					      int quiet,
					      void *cb_data,
					      struct transport *transport)
{
	struct child_process rev_list;
	const char *argv[] = {"rev-list", "--objects",
			      "--stdin", "--not", "--all", NULL, NULL};
	char commit[41];
	unsigned char sha1[20];
	int err = 0;
	struct packed_git *new_pack = NULL;

	if (fn(cb_data, sha1))
		return err;

	if (transport && transport->smart_options &&
	    transport->smart_options->self_contained_and_connected &&
	    transport->pack_lockfile &&
	    !suffixcmp(transport->pack_lockfile, ".keep")) {
		struct strbuf idx_file = STRBUF_INIT;
		strbuf_addstr(&idx_file, transport->pack_lockfile);
		strbuf_setlen(&idx_file, idx_file.len - 5); /* ".keep" */
		strbuf_addstr(&idx_file, ".idx");
		new_pack = add_packed_git(idx_file.buf, idx_file.len, 1);
		strbuf_release(&idx_file);
	}

	if (quiet)
		argv[5] = "--quiet";

	memset(&rev_list, 0, sizeof(rev_list));
	rev_list.argv = argv;
	rev_list.git_cmd = 1;
	rev_list.in = -1;
	rev_list.no_stdout = 1;
	rev_list.no_stderr = quiet;
	if (start_command(&rev_list))
		return error(_("Could not run 'git rev-list'"));

	sigchain_push(SIGPIPE, SIG_IGN);

	commit[40] = '\n';
	do {
		/*
		 * If index-pack already checked that:
		 * - there are no dangling pointers in the new pack
		 * - the pack is self contained
		 * Then if the updated ref is in the new pack, then we
		 * are sure the ref is good and not sending it to
		 * rev-list for verification.
		 */
		if (new_pack && find_pack_entry_one(sha1, new_pack))
			continue;

		memcpy(commit, sha1_to_hex(sha1), 40);
		if (write_in_full(rev_list.in, commit, 41) < 0) {
			if (errno != EPIPE && errno != EINVAL)
				error(_("failed write to rev-list: %s"),
				      strerror(errno));
			err = -1;
			break;
		}
	} while (!fn(cb_data, sha1));

	if (close(rev_list.in)) {
		error(_("failed to close rev-list's stdin: %s"), strerror(errno));
		err = -1;
	}

	sigchain_pop(SIGPIPE);
	return finish_command(&rev_list) || err;
}