tinygo/src/os/file_go_116.go
2021-09-06 12:39:40 +02:00

113 строки
3,4 КиБ
Go

// +build go1.16
package os
import (
"io"
"io/fs"
)
type (
DirEntry = fs.DirEntry
FileMode = fs.FileMode
FileInfo = fs.FileInfo
)
func (f *File) ReadDir(n int) ([]DirEntry, error) {
return nil, &PathError{"ReadDir", f.name, ErrNotImplemented}
}
func ReadDir(name string) ([]DirEntry, error) {
return nil, &PathError{"ReadDir", name, ErrNotImplemented}
}
// The followings are copied from Go 1.16 official implementation:
// https://github.com/golang/go/blob/go1.16/src/os/file.go
// ReadFile reads the named file and returns the contents.
// A successful call returns err == nil, not err == EOF.
// Because ReadFile reads the whole file, it does not treat an EOF from Read
// as an error to be reported.
func ReadFile(name string) ([]byte, error) {
f, err := Open(name)
if err != nil {
return nil, err
}
defer f.Close()
var size int
if info, err := f.Stat(); err == nil {
size64 := info.Size()
if int64(int(size64)) == size64 {
size = int(size64)
}
}
size++ // one byte for final read at EOF
// If a file claims a small size, read at least 512 bytes.
// In particular, files in Linux's /proc claim size 0 but
// then do not work right if read in small pieces,
// so an initial read of 1 byte would not work correctly.
if size < 512 {
size = 512
}
data := make([]byte, 0, size)
for {
if len(data) >= cap(data) {
d := append(data[:cap(data)], 0)
data = d[:len(data)]
}
n, err := f.Read(data[len(data):cap(data)])
data = data[:len(data)+n]
if err != nil {
if err == io.EOF {
err = nil
}
return data, err
}
}
}
// WriteFile writes data to the named file, creating it if necessary.
// If the file does not exist, WriteFile creates it with permissions perm (before umask);
// otherwise WriteFile truncates it before writing, without changing permissions.
func WriteFile(name string, data []byte, perm FileMode) error {
f, err := OpenFile(name, O_WRONLY|O_CREATE|O_TRUNC, perm)
if err != nil {
return err
}
_, err = f.Write(data)
if err1 := f.Close(); err1 != nil && err == nil {
err = err1
}
return err
}
// The defined file mode bits are the most significant bits of the FileMode.
// The nine least-significant bits are the standard Unix rwxrwxrwx permissions.
// The values of these bits should be considered part of the public API and
// may be used in wire protocols or disk representations: they must not be
// changed, although new bits might be added.
const (
// The single letters are the abbreviations
// used by the String method's formatting.
ModeDir = fs.ModeDir // d: is a directory
ModeAppend = fs.ModeAppend // a: append-only
ModeExclusive = fs.ModeExclusive // l: exclusive use
ModeTemporary = fs.ModeTemporary // T: temporary file; Plan 9 only
ModeSymlink = fs.ModeSymlink // L: symbolic link
ModeDevice = fs.ModeDevice // D: device file
ModeNamedPipe = fs.ModeNamedPipe // p: named pipe (FIFO)
ModeSocket = fs.ModeSocket // S: Unix domain socket
ModeSetuid = fs.ModeSetuid // u: setuid
ModeSetgid = fs.ModeSetgid // g: setgid
ModeCharDevice = fs.ModeCharDevice // c: Unix character device, when ModeDevice is set
ModeSticky = fs.ModeSticky // t: sticky
ModeIrregular = fs.ModeIrregular // ?: non-regular file; nothing else is known about this file
// Mask for the type bits. For regular files, none will be set.
ModeType = fs.ModeType
ModePerm = fs.ModePerm // Unix permission bits, 0o777
)