zig build package hashes are missing path names and executable bit for each file

[andrewrk]

zig/src/Package.zig

Lines 453 to 510 in d813cef

	fn computePackageHash(
	thread_pool: *ThreadPool,
	pkg_dir: fs.IterableDir,
	) ![Hash.digest_length]u8 {
	const gpa = thread_pool.allocator;
	// We'll use an arena allocator for the path name strings since they all
	// need to be in memory for sorting.
	var arena_instance = std.heap.ArenaAllocator.init(gpa);
	defer arena_instance.deinit();
	const arena = arena_instance.allocator();
	// Collect all files, recursively, then sort.
	var all_files = std.ArrayList(*HashedFile).init(gpa);
	defer all_files.deinit();
	var walker = try pkg_dir.walk(gpa);
	defer walker.deinit();
	{
	// The final hash will be a hash of each file hashed independently. This
	// allows hashing in parallel.
	var wait_group: WaitGroup = .{};
	defer wait_group.wait();
	while (try walker.next()) |entry| {
	switch (entry.kind) {
	.Directory => continue,
	.File => {},
	else => return error.IllegalFileTypeInPackage,
	}
	const hashed_file = try arena.create(HashedFile);
	hashed_file.* = .{
	.path = try arena.dupe(u8, entry.path),
	.hash = undefined, // to be populated by the worker
	.failure = undefined, // to be populated by the worker
	};
	wait_group.start();
	try thread_pool.spawn(workerHashFile, .{ pkg_dir.dir, hashed_file, &wait_group });
	try all_files.append(hashed_file);
	}
	}
	std.sort.sort(*HashedFile, all_files.items, {}, HashedFile.lessThan);
	var hasher = Hash.init(.{});
	var any_failures = false;
	for (all_files.items) |hashed_file| {
	hashed_file.failure catch |err| {
	any_failures = true;
	std.log.err("unable to hash '{s}': {s}", .{ hashed_file.path, @errorName(err) });
	};
	hasher.update(&hashed_file.hash);
	}
	if (any_failures) return error.PackageHashUnavailable;
	return hasher.finalResult();
	}

2 problems to solve:

• file names are not included in the hash
• executable bit (true/false) is not included in the hash

This will cause breakage because the hashes will change. It's fine, nobody is using the package manager yet. Go for it. Another breaking change to the hash is #14284.