maintner/internal/robustio/robustio.go

// Copyright 2019 The Go 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 robustio wraps I/O functions that are prone to failure on Windows,
// transparently retrying errors up to an arbitrary timeout.
//
// Errors are classified heuristically and retries are bounded, so the functions
// in this package do not completely eliminate spurious errors. However, they do
// significantly reduce the rate of failure in practice.
//
// If so, the error will likely wrap one of:
// The functions in this package do not completely eliminate spurious errors,
// but substantially reduce their rate of occurrence in practice.
//
// This package is a reduced copy of cmd/go/internal/robustio.
// TODO(#36163): Switch maintner to use file-locking instead of
// (or in addition to) atomic renames.
package robustio

// Rename is like os.Rename, but on Windows retries errors that may occur if the
// file is concurrently read or overwritten.
//
// (See golang.org/issue/31247 and golang.org/issue/32188.)
func Rename(oldpath, newpath string) error {
	return rename(oldpath, newpath)
}

// ReadFile is like os.ReadFile, but on Windows retries errors that may
// occur if the file is concurrently replaced.
//
// (See golang.org/issue/31247 and golang.org/issue/32188.)
func ReadFile(filename string) ([]byte, error) {
	return readFile(filename)
}

// RemoveAll is like os.RemoveAll, but on Windows retries errors that may occur
// if an executable file in the directory has recently been executed.
//
// (See golang.org/issue/19491.)
func RemoveAll(path string) error {
	return removeAll(path)
}

// IsEphemeralError reports whether err is one of the errors that the functions
// in this package attempt to mitigate.
//
// Errors considered ephemeral include:
//   - syscall.ERROR_ACCESS_DENIED
//   - syscall.ERROR_FILE_NOT_FOUND
//   - internal/syscall/windows.ERROR_SHARING_VIOLATION
//
// This set may be expanded in the future; programs must not rely on the
// non-ephemerality of any given error.
func IsEphemeralError(err error) bool {
	return isEphemeralError(err)
}