fxicfg/builtins/fxicfg.go

// Copyright 2019 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

package builtins

import (
	"path/filepath"

	"fuchsia.googlesource.com/infra/infra/fxicfg/errs"

	"fuchsia.googlesource.com/infra/infra/fxicfg/state"
	"go.starlark.net/starlark"
)

// setOutputDir sets the directory where output files are generated. This must be given
// relative to the main starlark entrypoint file. It is an error to call this more than
// once, even if the directory is the same each time.
func setOutputDir(thread *starlark.Thread, fn *starlark.Builtin, args starlark.Tuple, kwargs []starlark.Tuple) (starlark.Value, error) {
	do := func() error {
		var dir string
		if err := starlark.UnpackPositionalArgs("set_output_dir", args, kwargs, 0, &dir); err != nil {
			return err
		}
		s, err := state.GetThreadState(thread)
		if err != nil {
			return err
		}
		if s.OutputDir != "" {
			return errs.WithReason(errs.ErrIllegalWrite, "output dir already set to %q", s.OutputDir)
		}
		s.OutputDir = dir
		state.SetThreadState(thread, s)
		return nil
	}

	return starlark.None, do()
}

// addOutputFile registers a file to be generated at the end of execution. The path to the
// file is treated as relative to the directory given to set_output_dir. If an absolute
// path is given, an error is returned.
func addOutputFile(thread *starlark.Thread, fn *starlark.Builtin, args starlark.Tuple, kwargs []starlark.Tuple) (starlark.Value, error) {
	do := func() error {
		var path, textproto string
		if err := starlark.UnpackArgs("add_output_file", args, kwargs, "path", &path, "data", &textproto); err != nil {
			return err
		}
		s, err := state.GetThreadState(thread)
		if err != nil {
			return err
		}
		if path == "" {
			return errs.WithReason(errs.ErrInvalidArg, "path must not be empty")
		}
		if filepath.IsAbs(path) {
			return errs.WithReason(errs.ErrInvalidArg, "%q is not relative to output dir", path)
		}
		if _, ok := s.OutputFiles[path]; ok {
			return errs.WithReason(errs.ErrInvalidArg, "%q has already been added", path)
		}
		s.OutputFiles[path] = []byte(textproto)
		state.SetThreadState(thread, s)
		return nil
	}

	return starlark.None, do()
}