diff options
Diffstat (limited to 'src/pkg/io/ioutil/ioutil.go')
-rw-r--r-- | src/pkg/io/ioutil/ioutil.go | 165 |
1 files changed, 0 insertions, 165 deletions
diff --git a/src/pkg/io/ioutil/ioutil.go b/src/pkg/io/ioutil/ioutil.go deleted file mode 100644 index 909a81563..000000000 --- a/src/pkg/io/ioutil/ioutil.go +++ /dev/null @@ -1,165 +0,0 @@ -// Copyright 2009 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 ioutil implements some I/O utility functions. -package ioutil - -import ( - "bytes" - "io" - "os" - "sort" - "sync" -) - -// readAll reads from r until an error or EOF and returns the data it read -// from the internal buffer allocated with a specified capacity. -func readAll(r io.Reader, capacity int64) (b []byte, err error) { - buf := bytes.NewBuffer(make([]byte, 0, capacity)) - // If the buffer overflows, we will get bytes.ErrTooLarge. - // Return that as an error. Any other panic remains. - defer func() { - e := recover() - if e == nil { - return - } - if panicErr, ok := e.(error); ok && panicErr == bytes.ErrTooLarge { - err = panicErr - } else { - panic(e) - } - }() - _, err = buf.ReadFrom(r) - return buf.Bytes(), err -} - -// ReadAll reads from r until an error or EOF and returns the data it read. -// A successful call returns err == nil, not err == EOF. Because ReadAll is -// defined to read from src until EOF, it does not treat an EOF from Read -// as an error to be reported. -func ReadAll(r io.Reader) ([]byte, error) { - return readAll(r, bytes.MinRead) -} - -// ReadFile reads the file named by filename 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(filename string) ([]byte, error) { - f, err := os.Open(filename) - if err != nil { - return nil, err - } - defer f.Close() - // It's a good but not certain bet that FileInfo will tell us exactly how much to - // read, so let's try it but be prepared for the answer to be wrong. - var n int64 - - if fi, err := f.Stat(); err == nil { - // Don't preallocate a huge buffer, just in case. - if size := fi.Size(); size < 1e9 { - n = size - } - } - // As initial capacity for readAll, use n + a little extra in case Size is zero, - // and to avoid another allocation after Read has filled the buffer. The readAll - // call will read into its allocated internal buffer cheaply. If the size was - // wrong, we'll either waste some space off the end or reallocate as needed, but - // in the overwhelmingly common case we'll get it just right. - return readAll(f, n+bytes.MinRead) -} - -// WriteFile writes data to a file named by filename. -// If the file does not exist, WriteFile creates it with permissions perm; -// otherwise WriteFile truncates it before writing. -func WriteFile(filename string, data []byte, perm os.FileMode) error { - f, err := os.OpenFile(filename, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, perm) - if err != nil { - return err - } - n, err := f.Write(data) - if err == nil && n < len(data) { - err = io.ErrShortWrite - } - if err1 := f.Close(); err == nil { - err = err1 - } - return err -} - -// byName implements sort.Interface. -type byName []os.FileInfo - -func (f byName) Len() int { return len(f) } -func (f byName) Less(i, j int) bool { return f[i].Name() < f[j].Name() } -func (f byName) Swap(i, j int) { f[i], f[j] = f[j], f[i] } - -// ReadDir reads the directory named by dirname and returns -// a list of sorted directory entries. -func ReadDir(dirname string) ([]os.FileInfo, error) { - f, err := os.Open(dirname) - if err != nil { - return nil, err - } - list, err := f.Readdir(-1) - f.Close() - if err != nil { - return nil, err - } - sort.Sort(byName(list)) - return list, nil -} - -type nopCloser struct { - io.Reader -} - -func (nopCloser) Close() error { return nil } - -// NopCloser returns a ReadCloser with a no-op Close method wrapping -// the provided Reader r. -func NopCloser(r io.Reader) io.ReadCloser { - return nopCloser{r} -} - -type devNull int - -// devNull implements ReaderFrom as an optimization so io.Copy to -// ioutil.Discard can avoid doing unnecessary work. -var _ io.ReaderFrom = devNull(0) - -func (devNull) Write(p []byte) (int, error) { - return len(p), nil -} - -func (devNull) WriteString(s string) (int, error) { - return len(s), nil -} - -var blackHolePool = sync.Pool{ - New: func() interface{} { - b := make([]byte, 8192) - return &b - }, -} - -func (devNull) ReadFrom(r io.Reader) (n int64, err error) { - bufp := blackHolePool.Get().(*[]byte) - readSize := 0 - for { - readSize, err = r.Read(*bufp) - n += int64(readSize) - if err != nil { - blackHolePool.Put(bufp) - if err == io.EOF { - return n, nil - } - return - } - } -} - -// Discard is an io.Writer on which all Write calls succeed -// without doing anything. -var Discard io.Writer = devNull(0) |