mirror of
https://github.com/golang/go
synced 2024-11-24 21:00:09 -07:00
io: use error, add EOF, avoid os
R=r, r CC=golang-dev https://golang.org/cl/5311068
This commit is contained in:
Russ Cox
parent
c14f71c788
commit
c06cf03f0b
102
src/pkg/io/io.go
102
src/pkg/io/io.go
@ -8,25 +8,30 @@
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// abstract the functionality, plus some other related primitives.
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package io
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import "os"
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// Error represents an unexpected I/O behavior.
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type Error struct {
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ErrorString string
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}
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func (err *Error) String() string { return err.ErrorString }
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func (err *Error) Error() string { return err.ErrorString }
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// ErrShortWrite means that a write accepted fewer bytes than requested
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// but failed to return an explicit error.
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var ErrShortWrite os.Error = &Error{"short write"}
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var ErrShortWrite error = &Error{"short write"}
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// ErrShortBuffer means that a read required a longer buffer than was provided.
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var ErrShortBuffer os.Error = &Error{"short buffer"}
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var ErrShortBuffer error = &Error{"short buffer"}
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// ErrUnexpectedEOF means that os.EOF was encountered in the
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// EOF is the error returned by Read when no more input is available.
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// Functions should return EOF only to signal a graceful end of input.
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// If the EOF occurs unexpectedly in a structured data stream,
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// the appropriate error is either ErrUnexpectedEOF or some other error
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// giving more detail.
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var EOF error = &Error{"EOF"}
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// ErrUnexpectedEOF means that EOF was encountered in the
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// middle of reading a fixed-size block or data structure.
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var ErrUnexpectedEOF os.Error = &Error{"unexpected EOF"}
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var ErrUnexpectedEOF error = &Error{"unexpected EOF"}
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// Reader is the interface that wraps the basic Read method.
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//
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@ -42,15 +47,15 @@ var ErrUnexpectedEOF os.Error = &Error{"unexpected EOF"}
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// or return the error (and n == 0) from a subsequent call.
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// An instance of this general case is that a Reader returning
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// a non-zero number of bytes at the end of the input stream may
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// return either err == os.EOF or err == nil. The next Read should
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// return 0, os.EOF regardless.
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// return either err == EOF or err == nil. The next Read should
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// return 0, EOF regardless.
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//
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// Callers should always process the n > 0 bytes returned before
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// considering the error err. Doing so correctly handles I/O errors
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// that happen after reading some bytes and also both of the
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// allowed EOF behaviors.
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type Reader interface {
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Read(p []byte) (n int, err os.Error)
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Read(p []byte) (n int, err error)
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}
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// Writer is the interface that wraps the basic Write method.
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@ -60,12 +65,12 @@ type Reader interface {
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// and any error encountered that caused the write to stop early.
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// Write must return a non-nil error if it returns n < len(p).
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type Writer interface {
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Write(p []byte) (n int, err os.Error)
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Write(p []byte) (n int, err error)
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}
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// Closer is the interface that wraps the basic Close method.
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type Closer interface {
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Close() os.Error
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Close() error
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}
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// Seeker is the interface that wraps the basic Seek method.
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@ -76,7 +81,7 @@ type Closer interface {
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// relative to the end. Seek returns the new offset and an Error, if
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// any.
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type Seeker interface {
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Seek(offset int64, whence int) (ret int64, err os.Error)
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Seek(offset int64, whence int) (ret int64, err error)
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}
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// ReadWriter is the interface that groups the basic Read and Write methods.
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@ -125,12 +130,12 @@ type ReadWriteSeeker interface {
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// ReaderFrom is the interface that wraps the ReadFrom method.
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type ReaderFrom interface {
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ReadFrom(r Reader) (n int64, err os.Error)
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ReadFrom(r Reader) (n int64, err error)
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}
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// WriterTo is the interface that wraps the WriteTo method.
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type WriterTo interface {
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WriteTo(w Writer) (n int64, err os.Error)
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WriteTo(w Writer) (n int64, err error)
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}
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// ReaderAt is the interface that wraps the basic ReadAt method.
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@ -149,13 +154,13 @@ type WriterTo interface {
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// In this respect ReadAt is different from Read.
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//
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// If the n = len(p) bytes returned by ReadAt are at the end of the
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// input source, ReadAt may return either err == os.EOF or err == nil.
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// input source, ReadAt may return either err == EOF or err == nil.
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//
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// If ReadAt is reading from an input source with a seek offset,
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// ReadAt should not affect nor be affected by the underlying
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// seek offset.
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type ReaderAt interface {
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ReadAt(p []byte, off int64) (n int, err os.Error)
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ReadAt(p []byte, off int64) (n int, err error)
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}
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// WriterAt is the interface that wraps the basic WriteAt method.
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@ -165,7 +170,7 @@ type ReaderAt interface {
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// and any error encountered that caused the write to stop early.
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// WriteAt must return a non-nil error if it returns n < len(p).
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type WriterAt interface {
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WriteAt(p []byte, off int64) (n int, err os.Error)
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WriteAt(p []byte, off int64) (n int, err error)
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}
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// ByteReader is the interface that wraps the ReadByte method.
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@ -173,7 +178,7 @@ type WriterAt interface {
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// ReadByte reads and returns the next byte from the input.
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// If no byte is available, err will be set.
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type ByteReader interface {
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ReadByte() (c byte, err os.Error)
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ReadByte() (c byte, err error)
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}
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// ByteScanner is the interface that adds the UnreadByte method to the
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@ -185,7 +190,7 @@ type ByteReader interface {
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// call to ReadByte.
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type ByteScanner interface {
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ByteReader
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UnreadByte() os.Error
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UnreadByte() error
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}
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// RuneReader is the interface that wraps the ReadRune method.
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@ -194,7 +199,7 @@ type ByteScanner interface {
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// and returns the rune and its size in bytes. If no character is
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// available, err will be set.
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type RuneReader interface {
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ReadRune() (r rune, size int, err os.Error)
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ReadRune() (r rune, size int, err error)
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}
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// RuneScanner is the interface that adds the UnreadRune method to the
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@ -206,16 +211,16 @@ type RuneReader interface {
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// call to ReadRune.
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type RuneScanner interface {
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RuneReader
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UnreadRune() os.Error
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UnreadRune() error
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}
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// stringWriter is the interface that wraps the WriteString method.
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type stringWriter interface {
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WriteString(s string) (n int, err os.Error)
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WriteString(s string) (n int, err error)
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}
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// WriteString writes the contents of the string s to w, which accepts an array of bytes.
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func WriteString(w Writer, s string) (n int, err os.Error) {
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func WriteString(w Writer, s string) (n int, err error) {
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if sw, ok := w.(stringWriter); ok {
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return sw.WriteString(s)
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}
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@ -224,11 +229,11 @@ func WriteString(w Writer, s string) (n int, err os.Error) {
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// ReadAtLeast reads from r into buf until it has read at least min bytes.
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// It returns the number of bytes copied and an error if fewer bytes were read.
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// The error is os.EOF only if no bytes were read.
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// The error is EOF only if no bytes were read.
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// If an EOF happens after reading fewer than min bytes,
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// ReadAtLeast returns ErrUnexpectedEOF.
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// If min is greater than the length of buf, ReadAtLeast returns ErrShortBuffer.
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func ReadAtLeast(r Reader, buf []byte, min int) (n int, err os.Error) {
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func ReadAtLeast(r Reader, buf []byte, min int) (n int, err error) {
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if len(buf) < min {
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return 0, ErrShortBuffer
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}
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@ -237,7 +242,7 @@ func ReadAtLeast(r Reader, buf []byte, min int) (n int, err os.Error) {
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nn, err = r.Read(buf[n:])
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n += nn
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}
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if err == os.EOF {
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if err == EOF {
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if n >= min {
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err = nil
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} else if n > 0 {
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@ -249,10 +254,10 @@ func ReadAtLeast(r Reader, buf []byte, min int) (n int, err os.Error) {
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// ReadFull reads exactly len(buf) bytes from r into buf.
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// It returns the number of bytes copied and an error if fewer bytes were read.
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// The error is os.EOF only if no bytes were read.
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// The error is EOF only if no bytes were read.
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// If an EOF happens after reading some but not all the bytes,
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// ReadFull returns ErrUnexpectedEOF.
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func ReadFull(r Reader, buf []byte) (n int, err os.Error) {
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func ReadFull(r Reader, buf []byte) (n int, err error) {
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return ReadAtLeast(r, buf, len(buf))
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}
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@ -260,18 +265,18 @@ func ReadFull(r Reader, buf []byte) (n int, err os.Error) {
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// It returns the number of bytes copied and the earliest
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// error encountered while copying. Because Read can
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// return the full amount requested as well as an error
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// (including os.EOF), so can CopyN.
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// (including EOF), so can CopyN.
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//
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// If dst implements the ReaderFrom interface,
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// the copy is implemented by calling dst.ReadFrom(src).
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func CopyN(dst Writer, src Reader, n int64) (written int64, err os.Error) {
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func CopyN(dst Writer, src Reader, n int64) (written int64, err error) {
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// If the writer has a ReadFrom method, use it to do the copy.
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// Avoids a buffer allocation and a copy.
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if rt, ok := dst.(ReaderFrom); ok {
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written, err = rt.ReadFrom(LimitReader(src, n))
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if written < n && err == nil {
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// rt stopped early; must have been EOF.
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err = os.EOF
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err = EOF
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}
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return
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}
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@ -308,7 +313,7 @@ func CopyN(dst Writer, src Reader, n int64) (written int64, err os.Error) {
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// on src or an error occurs. It returns the number of bytes
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// copied and the first error encountered while copying, if any.
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//
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// A successful Copy returns err == nil, not err == os.EOF.
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// A successful Copy returns err == nil, not err == EOF.
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// Because Copy is defined to read from src until EOF, it does
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// not treat an EOF from Read as an error to be reported.
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//
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@ -316,7 +321,7 @@ func CopyN(dst Writer, src Reader, n int64) (written int64, err os.Error) {
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// the copy is implemented by calling dst.ReadFrom(src).
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// Otherwise, if src implements the WriterTo interface,
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// the copy is implemented by calling src.WriteTo(dst).
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func Copy(dst Writer, src Reader) (written int64, err os.Error) {
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func Copy(dst Writer, src Reader) (written int64, err error) {
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// If the writer has a ReadFrom method, use it to do the copy.
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// Avoids an allocation and a copy.
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if rt, ok := dst.(ReaderFrom); ok {
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@ -343,7 +348,7 @@ func Copy(dst Writer, src Reader) (written int64, err os.Error) {
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break
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}
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}
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if er == os.EOF {
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if er == EOF {
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break
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}
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if er != nil {
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@ -355,7 +360,7 @@ func Copy(dst Writer, src Reader) (written int64, err os.Error) {
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}
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// LimitReader returns a Reader that reads from r
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// but stops with os.EOF after n bytes.
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// but stops with EOF after n bytes.
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// The underlying implementation is a *LimitedReader.
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func LimitReader(r Reader, n int64) Reader { return &LimitedReader{r, n} }
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@ -367,9 +372,9 @@ type LimitedReader struct {
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N int64 // max bytes remaining
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}
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func (l *LimitedReader) Read(p []byte) (n int, err os.Error) {
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func (l *LimitedReader) Read(p []byte) (n int, err error) {
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if l.N <= 0 {
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return 0, os.EOF
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return 0, EOF
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}
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if int64(len(p)) > l.N {
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p = p[0:l.N]
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@ -380,7 +385,7 @@ func (l *LimitedReader) Read(p []byte) (n int, err os.Error) {
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}
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// NewSectionReader returns a SectionReader that reads from r
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// starting at offset off and stops with os.EOF after n bytes.
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// starting at offset off and stops with EOF after n bytes.
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func NewSectionReader(r ReaderAt, off int64, n int64) *SectionReader {
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return &SectionReader{r, off, off, off + n}
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}
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@ -394,9 +399,9 @@ type SectionReader struct {
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limit int64
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}
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func (s *SectionReader) Read(p []byte) (n int, err os.Error) {
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func (s *SectionReader) Read(p []byte) (n int, err error) {
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if s.off >= s.limit {
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return 0, os.EOF
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return 0, EOF
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}
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if max := s.limit - s.off; int64(len(p)) > max {
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p = p[0:max]
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@ -406,10 +411,13 @@ func (s *SectionReader) Read(p []byte) (n int, err os.Error) {
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return
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}
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func (s *SectionReader) Seek(offset int64, whence int) (ret int64, err os.Error) {
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var errWhence = &Error{"Seek: invalid whence"}
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var errOffset = &Error{"Seek: invalid offset"}
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func (s *SectionReader) Seek(offset int64, whence int) (ret int64, err error) {
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switch whence {
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default:
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return 0, os.EINVAL
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return 0, errWhence
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case 0:
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offset += s.base
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case 1:
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@ -418,15 +426,15 @@ func (s *SectionReader) Seek(offset int64, whence int) (ret int64, err os.Error)
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offset += s.limit
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}
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if offset < s.base || offset > s.limit {
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return 0, os.EINVAL
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return 0, errOffset
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}
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s.off = offset
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return offset - s.base, nil
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}
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func (s *SectionReader) ReadAt(p []byte, off int64) (n int, err os.Error) {
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func (s *SectionReader) ReadAt(p []byte, off int64) (n int, err error) {
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if off < 0 || off >= s.limit-s.base {
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return 0, os.EOF
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return 0, EOF
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}
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off += s.base
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if max := s.limit - off; int64(len(p)) > max {
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@ -452,7 +460,7 @@ type teeReader struct {
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w Writer
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}
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func (t *teeReader) Read(p []byte) (n int, err os.Error) {
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func (t *teeReader) Read(p []byte) (n int, err error) {
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n, err = t.r.Read(p)
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if n > 0 {
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if n, err := t.w.Write(p[:n]); err != nil {
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@ -7,7 +7,6 @@ package io_test
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import (
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"bytes"
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. "io"
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"os"
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"strings"
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"testing"
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)
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@ -85,7 +84,7 @@ type noReadFrom struct {
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w Writer
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}
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func (w *noReadFrom) Write(p []byte) (n int, err os.Error) {
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func (w *noReadFrom) Write(p []byte) (n int, err error) {
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return w.w.Write(p)
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}
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@ -101,7 +100,7 @@ func TestCopyNEOF(t *testing.T) {
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}
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n, err = CopyN(&noReadFrom{b}, strings.NewReader("foo"), 4)
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if n != 3 || err != os.EOF {
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if n != 3 || err != EOF {
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t.Errorf("CopyN(noReadFrom, foo, 4) = %d, %v; want 3, EOF", n, err)
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}
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@ -111,7 +110,7 @@ func TestCopyNEOF(t *testing.T) {
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}
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n, err = CopyN(b, strings.NewReader("foo"), 4) // b has read from
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if n != 3 || err != os.EOF {
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if n != 3 || err != EOF {
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t.Errorf("CopyN(bytes.Buffer, foo, 4) = %d, %v; want 3, EOF", n, err)
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}
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}
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@ -121,16 +120,16 @@ func TestReadAtLeast(t *testing.T) {
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testReadAtLeast(t, &rb)
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}
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// A version of bytes.Buffer that returns n > 0, os.EOF on Read
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// A version of bytes.Buffer that returns n > 0, EOF on Read
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// when the input is exhausted.
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type dataAndEOFBuffer struct {
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bytes.Buffer
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}
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func (r *dataAndEOFBuffer) Read(p []byte) (n int, err os.Error) {
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func (r *dataAndEOFBuffer) Read(p []byte) (n int, err error) {
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n, err = r.Buffer.Read(p)
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if n > 0 && r.Buffer.Len() == 0 && err == nil {
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err = os.EOF
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err = EOF
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}
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return
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}
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@ -162,7 +161,7 @@ func testReadAtLeast(t *testing.T, rb ReadWriter) {
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t.Errorf("expected to have read 2 bytes, got %v", n)
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}
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n, err = ReadAtLeast(rb, buf, 2)
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if err != os.EOF {
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if err != EOF {
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t.Errorf("expected EOF, got %v", err)
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}
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if n != 0 {
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@ -193,14 +192,14 @@ func TestTeeReader(t *testing.T) {
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if !bytes.Equal(wb.Bytes(), src) {
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t.Errorf("bytes written = %q want %q", wb.Bytes(), src)
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}
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if n, err := r.Read(dst); n != 0 || err != os.EOF {
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if n, err := r.Read(dst); n != 0 || err != EOF {
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t.Errorf("r.Read at EOF = %d, %v want 0, EOF", n, err)
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}
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rb = bytes.NewBuffer(src)
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pr, pw := Pipe()
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pr.Close()
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r = TeeReader(rb, pw)
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if n, err := ReadFull(r, dst); n != 0 || err != os.EPIPE {
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if n, err := ReadFull(r, dst); n != 0 || err != ErrClosedPipe {
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t.Errorf("closed tee: ReadFull(r, dst) = %d, %v; want 0, EPIPE", n, err)
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}
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}
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@ -4,17 +4,15 @@
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package io
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import "os"
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|
||||
type multiReader struct {
|
||||
readers []Reader
|
||||
}
|
||||
|
||||
func (mr *multiReader) Read(p []byte) (n int, err os.Error) {
|
||||
func (mr *multiReader) Read(p []byte) (n int, err error) {
|
||||
for len(mr.readers) > 0 {
|
||||
n, err = mr.readers[0].Read(p)
|
||||
if n > 0 || err != os.EOF {
|
||||
if err == os.EOF {
|
||||
if n > 0 || err != EOF {
|
||||
if err == EOF {
|
||||
// Don't return EOF yet. There may be more bytes
|
||||
// in the remaining readers.
|
||||
err = nil
|
||||
@ -23,12 +21,12 @@ func (mr *multiReader) Read(p []byte) (n int, err os.Error) {
|
||||
}
|
||||
mr.readers = mr.readers[1:]
|
||||
}
|
||||
return 0, os.EOF
|
||||
return 0, EOF
|
||||
}
|
||||
|
||||
// MultiReader returns a Reader that's the logical concatenation of
|
||||
// the provided input readers. They're read sequentially. Once all
|
||||
// inputs are drained, Read will return os.EOF.
|
||||
// inputs are drained, Read will return EOF.
|
||||
func MultiReader(readers ...Reader) Reader {
|
||||
return &multiReader{readers}
|
||||
}
|
||||
@ -37,7 +35,7 @@ type multiWriter struct {
|
||||
writers []Writer
|
||||
}
|
||||
|
||||
func (t *multiWriter) Write(p []byte) (n int, err os.Error) {
|
||||
func (t *multiWriter) Write(p []byte) (n int, err error) {
|
||||
for _, w := range t.writers {
|
||||
n, err = w.Write(p)
|
||||
if err != nil {
|
||||
|
||||
@ -9,7 +9,6 @@ import (
|
||||
"bytes"
|
||||
"crypto/sha1"
|
||||
"fmt"
|
||||
"os"
|
||||
"strings"
|
||||
"testing"
|
||||
)
|
||||
@ -26,7 +25,7 @@ func TestMultiReader(t *testing.T) {
|
||||
buf = make([]byte, 20)
|
||||
tests()
|
||||
}
|
||||
expectRead := func(size int, expected string, eerr os.Error) {
|
||||
expectRead := func(size int, expected string, eerr error) {
|
||||
nread++
|
||||
n, gerr := mr.Read(buf[0:size])
|
||||
if n != len(expected) {
|
||||
@ -48,13 +47,13 @@ func TestMultiReader(t *testing.T) {
|
||||
expectRead(2, "fo", nil)
|
||||
expectRead(5, "o ", nil)
|
||||
expectRead(5, "bar", nil)
|
||||
expectRead(5, "", os.EOF)
|
||||
expectRead(5, "", EOF)
|
||||
})
|
||||
withFooBar(func() {
|
||||
expectRead(4, "foo ", nil)
|
||||
expectRead(1, "b", nil)
|
||||
expectRead(3, "ar", nil)
|
||||
expectRead(1, "", os.EOF)
|
||||
expectRead(1, "", EOF)
|
||||
})
|
||||
withFooBar(func() {
|
||||
expectRead(5, "foo ", nil)
|
||||
|
||||
@ -7,14 +7,14 @@
|
||||
|
||||
package io
|
||||
|
||||
import (
|
||||
"os"
|
||||
"sync"
|
||||
)
|
||||
import "sync"
|
||||
|
||||
// ErrClosedPipe is the error used for read or write operations on a closed pipe.
|
||||
var ErrClosedPipe = &Error{"io: read/write on closed pipe"}
|
||||
|
||||
type pipeResult struct {
|
||||
n int
|
||||
err os.Error
|
||||
err error
|
||||
}
|
||||
|
||||
// A pipe is the shared pipe structure underlying PipeReader and PipeWriter.
|
||||
@ -25,11 +25,11 @@ type pipe struct {
|
||||
data []byte // data remaining in pending write
|
||||
rwait sync.Cond // waiting reader
|
||||
wwait sync.Cond // waiting writer
|
||||
rerr os.Error // if reader closed, error to give writes
|
||||
werr os.Error // if writer closed, error to give reads
|
||||
rerr error // if reader closed, error to give writes
|
||||
werr error // if writer closed, error to give reads
|
||||
}
|
||||
|
||||
func (p *pipe) read(b []byte) (n int, err os.Error) {
|
||||
func (p *pipe) read(b []byte) (n int, err error) {
|
||||
// One reader at a time.
|
||||
p.rl.Lock()
|
||||
defer p.rl.Unlock()
|
||||
@ -38,7 +38,7 @@ func (p *pipe) read(b []byte) (n int, err os.Error) {
|
||||
defer p.l.Unlock()
|
||||
for {
|
||||
if p.rerr != nil {
|
||||
return 0, os.EINVAL
|
||||
return 0, ErrClosedPipe
|
||||
}
|
||||
if p.data != nil {
|
||||
break
|
||||
@ -59,7 +59,7 @@ func (p *pipe) read(b []byte) (n int, err os.Error) {
|
||||
|
||||
var zero [0]byte
|
||||
|
||||
func (p *pipe) write(b []byte) (n int, err os.Error) {
|
||||
func (p *pipe) write(b []byte) (n int, err error) {
|
||||
// pipe uses nil to mean not available
|
||||
if b == nil {
|
||||
b = zero[:]
|
||||
@ -82,7 +82,7 @@ func (p *pipe) write(b []byte) (n int, err os.Error) {
|
||||
break
|
||||
}
|
||||
if p.werr != nil {
|
||||
err = os.EINVAL
|
||||
err = ErrClosedPipe
|
||||
}
|
||||
p.wwait.Wait()
|
||||
}
|
||||
@ -91,9 +91,9 @@ func (p *pipe) write(b []byte) (n int, err os.Error) {
|
||||
return
|
||||
}
|
||||
|
||||
func (p *pipe) rclose(err os.Error) {
|
||||
func (p *pipe) rclose(err error) {
|
||||
if err == nil {
|
||||
err = os.EPIPE
|
||||
err = ErrClosedPipe
|
||||
}
|
||||
p.l.Lock()
|
||||
defer p.l.Unlock()
|
||||
@ -102,9 +102,9 @@ func (p *pipe) rclose(err os.Error) {
|
||||
p.wwait.Signal()
|
||||
}
|
||||
|
||||
func (p *pipe) wclose(err os.Error) {
|
||||
func (p *pipe) wclose(err error) {
|
||||
if err == nil {
|
||||
err = os.EOF
|
||||
err = EOF
|
||||
}
|
||||
p.l.Lock()
|
||||
defer p.l.Unlock()
|
||||
@ -122,20 +122,20 @@ type PipeReader struct {
|
||||
// it reads data from the pipe, blocking until a writer
|
||||
// arrives or the write end is closed.
|
||||
// If the write end is closed with an error, that error is
|
||||
// returned as err; otherwise err is os.EOF.
|
||||
func (r *PipeReader) Read(data []byte) (n int, err os.Error) {
|
||||
// returned as err; otherwise err is EOF.
|
||||
func (r *PipeReader) Read(data []byte) (n int, err error) {
|
||||
return r.p.read(data)
|
||||
}
|
||||
|
||||
// Close closes the reader; subsequent writes to the
|
||||
// write half of the pipe will return the error os.EPIPE.
|
||||
func (r *PipeReader) Close() os.Error {
|
||||
// write half of the pipe will return the error ErrClosedPipe.
|
||||
func (r *PipeReader) Close() error {
|
||||
return r.CloseWithError(nil)
|
||||
}
|
||||
|
||||
// CloseWithError closes the reader; subsequent writes
|
||||
// to the write half of the pipe will return the error err.
|
||||
func (r *PipeReader) CloseWithError(err os.Error) os.Error {
|
||||
func (r *PipeReader) CloseWithError(err error) error {
|
||||
r.p.rclose(err)
|
||||
return nil
|
||||
}
|
||||
@ -149,20 +149,20 @@ type PipeWriter struct {
|
||||
// it writes data to the pipe, blocking until readers
|
||||
// have consumed all the data or the read end is closed.
|
||||
// If the read end is closed with an error, that err is
|
||||
// returned as err; otherwise err is os.EPIPE.
|
||||
func (w *PipeWriter) Write(data []byte) (n int, err os.Error) {
|
||||
// returned as err; otherwise err is ErrClosedPipe.
|
||||
func (w *PipeWriter) Write(data []byte) (n int, err error) {
|
||||
return w.p.write(data)
|
||||
}
|
||||
|
||||
// Close closes the writer; subsequent reads from the
|
||||
// read half of the pipe will return no bytes and os.EOF.
|
||||
func (w *PipeWriter) Close() os.Error {
|
||||
// read half of the pipe will return no bytes and EOF.
|
||||
func (w *PipeWriter) Close() error {
|
||||
return w.CloseWithError(nil)
|
||||
}
|
||||
|
||||
// CloseWithError closes the writer; subsequent reads from the
|
||||
// read half of the pipe will return no bytes and the error err.
|
||||
func (w *PipeWriter) CloseWithError(err os.Error) os.Error {
|
||||
func (w *PipeWriter) CloseWithError(err error) error {
|
||||
w.p.wclose(err)
|
||||
return nil
|
||||
}
|
||||
|
||||
@ -7,7 +7,6 @@ package io_test
|
||||
import (
|
||||
"fmt"
|
||||
. "io"
|
||||
"os"
|
||||
"testing"
|
||||
"time"
|
||||
)
|
||||
@ -44,7 +43,7 @@ func reader(t *testing.T, r Reader, c chan int) {
|
||||
var buf = make([]byte, 64)
|
||||
for {
|
||||
n, err := r.Read(buf)
|
||||
if err == os.EOF {
|
||||
if err == EOF {
|
||||
c <- 0
|
||||
break
|
||||
}
|
||||
@ -84,7 +83,7 @@ func TestPipe2(t *testing.T) {
|
||||
|
||||
type pipeReturn struct {
|
||||
n int
|
||||
err os.Error
|
||||
err error
|
||||
}
|
||||
|
||||
// Test a large write that requires multiple reads to satisfy.
|
||||
@ -106,7 +105,7 @@ func TestPipe3(t *testing.T) {
|
||||
tot := 0
|
||||
for n := 1; n <= 256; n *= 2 {
|
||||
nn, err := r.Read(rdat[tot : tot+n])
|
||||
if err != nil && err != os.EOF {
|
||||
if err != nil && err != EOF {
|
||||
t.Fatalf("read: %v", err)
|
||||
}
|
||||
|
||||
@ -116,7 +115,7 @@ func TestPipe3(t *testing.T) {
|
||||
expect = 1
|
||||
} else if n == 256 {
|
||||
expect = 0
|
||||
if err != os.EOF {
|
||||
if err != EOF {
|
||||
t.Fatalf("read at end: %v", err)
|
||||
}
|
||||
}
|
||||
@ -142,13 +141,13 @@ func TestPipe3(t *testing.T) {
|
||||
// Test read after/before writer close.
|
||||
|
||||
type closer interface {
|
||||
CloseWithError(os.Error) os.Error
|
||||
Close() os.Error
|
||||
CloseWithError(error) error
|
||||
Close() error
|
||||
}
|
||||
|
||||
type pipeTest struct {
|
||||
async bool
|
||||
err os.Error
|
||||
err error
|
||||
closeWithError bool
|
||||
}
|
||||
|
||||
@ -167,7 +166,7 @@ var pipeTests = []pipeTest{
|
||||
|
||||
func delayClose(t *testing.T, cl closer, ch chan int, tt pipeTest) {
|
||||
time.Sleep(1e6) // 1 ms
|
||||
var err os.Error
|
||||
var err error
|
||||
if tt.closeWithError {
|
||||
err = cl.CloseWithError(tt.err)
|
||||
} else {
|
||||
@ -193,7 +192,7 @@ func TestPipeReadClose(t *testing.T) {
|
||||
<-c
|
||||
want := tt.err
|
||||
if want == nil {
|
||||
want = os.EOF
|
||||
want = EOF
|
||||
}
|
||||
if err != want {
|
||||
t.Errorf("read from closed pipe: %v want %v", err, want)
|
||||
@ -214,8 +213,8 @@ func TestPipeReadClose2(t *testing.T) {
|
||||
go delayClose(t, r, c, pipeTest{})
|
||||
n, err := r.Read(make([]byte, 64))
|
||||
<-c
|
||||
if n != 0 || err != os.EINVAL {
|
||||
t.Errorf("read from closed pipe: %v, %v want %v, %v", n, err, 0, os.EINVAL)
|
||||
if n != 0 || err != ErrClosedPipe {
|
||||
t.Errorf("read from closed pipe: %v, %v want %v, %v", n, err, 0, ErrClosedPipe)
|
||||
}
|
||||
}
|
||||
|
||||
@ -234,7 +233,7 @@ func TestPipeWriteClose(t *testing.T) {
|
||||
<-c
|
||||
expect := tt.err
|
||||
if expect == nil {
|
||||
expect = os.EPIPE
|
||||
expect = ErrClosedPipe
|
||||
}
|
||||
if err != expect {
|
||||
t.Errorf("write on closed pipe: %v want %v", err, expect)
|
||||
|
||||
Loading…
Reference in New Issue
Block a user