moby/pkg/ioutils/buffer.go
Daniel Nephin 4f0d95fa6e Add canonical import comment
Signed-off-by: Daniel Nephin <dnephin@docker.com>
2018-02-05 16:51:57 -05:00

51 lines
857 B
Go

package ioutils // import "github.com/docker/docker/pkg/ioutils"
import (
"errors"
"io"
)
var errBufferFull = errors.New("buffer is full")
type fixedBuffer struct {
buf []byte
pos int
lastRead int
}
func (b *fixedBuffer) Write(p []byte) (int, error) {
n := copy(b.buf[b.pos:cap(b.buf)], p)
b.pos += n
if n < len(p) {
if b.pos == cap(b.buf) {
return n, errBufferFull
}
return n, io.ErrShortWrite
}
return n, nil
}
func (b *fixedBuffer) Read(p []byte) (int, error) {
n := copy(p, b.buf[b.lastRead:b.pos])
b.lastRead += n
return n, nil
}
func (b *fixedBuffer) Len() int {
return b.pos - b.lastRead
}
func (b *fixedBuffer) Cap() int {
return cap(b.buf)
}
func (b *fixedBuffer) Reset() {
b.pos = 0
b.lastRead = 0
b.buf = b.buf[:0]
}
func (b *fixedBuffer) String() string {
return string(b.buf[b.lastRead:b.pos])
}