Merge "simplify `m clean`"

function test_m_clean_works {

  setup

  # Create a directory with files that cannot be removed

  mkdir -p out/bad_directory_permissions

  touch out/bad_directory_permissions/unremovable_file

  # File permissions are fine but directory permissions are bad

  chmod a+rwx out/bad_directory_permissions/unremovable_file

  chmod a-rwx out/bad_directory_permissions

  mkdir -p out/some_directory

  touch out/some_directory/some_file

  run_soong clean

}

import (

	"bytes"

	"fmt"

	"io/fs"

	"io/ioutil"

	"os"

	"path/filepath"

	FILEMODE_USER_EXECUTE = FILEMODE_EXECUTE << FILEMODE_USER_SHIFT

)

// Ensures that files and directories in the out dir can be deleted.

// For example, Bazen can generate output directories where the write bit isn't set, causing 'm' clean' to fail.

func ensureOutDirRemovable(ctx Context, config Config) {

	err := filepath.WalkDir(config.OutDir(), func(path string, d fs.DirEntry, err error) error {

		if err != nil {

			return err

		}

		if d.IsDir() {

			info, err := d.Info()

			if err != nil {

				return err

			}

			// Equivalent to running chmod u+rwx on each directory

			newMode := info.Mode() | FILEMODE_USER_READ | FILEMODE_USER_WRITE | FILEMODE_USER_EXECUTE

			if err := os.Chmod(path, newMode); err != nil {

				return err

			}

		}

		// Continue walking the out dir...

		return nil

	})

	if err != nil && !os.IsNotExist(err) {

		// Display the error, but don't crash.

		ctx.Println(err.Error())

	}

}

// Remove everything under the out directory. Don't remove the out directory

// itself in case it's a symlink.

func clean(ctx Context, config Config) {

	ensureOutDirRemovable(ctx, config)

	removeGlobs(ctx, filepath.Join(config.OutDir(), "*"))

	ctx.Println("Entire build directory removed.")

}