text: #include "cache.h"
  #include "object-store.h"
  #include "run-command.h"
  #include "sigchain.h"
  #include "connected.h"
  #include "transport.h"
  #include "packfile.h"
  
  /*
   * 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_connected(oid_iterate_fn fn, void *cb_data,
  		    struct check_connected_options *opt)
  {
  	struct child_process rev_list = CHILD_PROCESS_INIT;
  	struct check_connected_options defaults = CHECK_CONNECTED_INIT;
  	char commit[GIT_MAX_HEXSZ + 1];
  	struct object_id oid;
  	int err = 0;
  	struct packed_git *new_pack = NULL;
  	struct transport *transport;
  	size_t base_len;
  
  	if (!opt)
  		opt = &defaults;
  	transport = opt->transport;
  
  	if (fn(cb_data, &oid)) {
  		if (opt->err_fd)
  			close(opt->err_fd);
  		return err;
  	}
  
  	if (transport && transport->smart_options &&
  	    transport->smart_options->self_contained_and_connected &&
  	    transport->pack_lockfile &&
  	    strip_suffix(transport->pack_lockfile, ".keep", &base_len)) {
  		struct strbuf idx_file = STRBUF_INIT;
  		strbuf_add(&idx_file, transport->pack_lockfile, base_len);
  		strbuf_addstr(&idx_file, ".idx");
  		new_pack = add_packed_git(idx_file.buf, idx_file.len, 1);
  		strbuf_release(&idx_file);
  	}
  
  	if (opt->check_refs_only) {
  		/*
  		 * For partial clones, we don't want to have to do a regular
  		 * connectivity check because we have to enumerate and exclude
  		 * all promisor objects (slow), and then the connectivity check
  		 * itself becomes a no-op because in a partial clone every
  		 * object is a promisor object. Instead, just make sure we
  		 * received the objects pointed to by each wanted ref.
  		 */
  		do {
  			if (!repo_has_object_file(the_repository, &oid))
  				return 1;
  		} while (!fn(cb_data, &oid));
  		return 0;
  	}
  
  	if (opt->shallow_file) {
  		argv_array_push(&rev_list.args, "--shallow-file");
  		argv_array_push(&rev_list.args, opt->shallow_file);
  	}
  	argv_array_push(&rev_list.args,"rev-list");
  	argv_array_push(&rev_list.args, "--objects");
  	argv_array_push(&rev_list.args, "--stdin");
  	if (repository_format_partial_clone)
  		argv_array_push(&rev_list.args, "--exclude-promisor-objects");
  	if (!opt->is_deepening_fetch) {
  		argv_array_push(&rev_list.args, "--not");
  		argv_array_push(&rev_list.args, "--all");
  	}
  	argv_array_push(&rev_list.args, "--quiet");
  	argv_array_push(&rev_list.args, "--alternate-refs");
  	if (opt->progress)
  		argv_array_pushf(&rev_list.args, "--progress=%s",
  				 _("Checking connectivity"));
  
  	rev_list.git_cmd = 1;
  	rev_list.env = opt->env;
  	rev_list.in = -1;
  	rev_list.no_stdout = 1;
  	if (opt->err_fd)
  		rev_list.err = opt->err_fd;
  	else
  		rev_list.no_stderr = opt->quiet;
  
  	if (start_command(&rev_list))
  		return error(_("Could not run 'git rev-list'"));
  
  	sigchain_push(SIGPIPE, SIG_IGN);
  
  	commit[GIT_SHA1_HEXSZ] = '\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(oid.hash, new_pack))
  			continue;
  
  		memcpy(commit, oid_to_hex(&oid), GIT_SHA1_HEXSZ);
  		if (write_in_full(rev_list.in, commit, GIT_SHA1_HEXSZ + 1) < 0) {
  			if (errno != EPIPE && errno != EINVAL)
  				error_errno(_("failed write to rev-list"));
  			err = -1;
  			break;
  		}
  	} while (!fn(cb_data, &oid));
  
  	if (close(rev_list.in))
  		err = error_errno(_("failed to close rev-list's stdin"));
  
  	sigchain_pop(SIGPIPE);
  	return finish_command(&rev_list) || err;
  }
  