/
writer.go
39 lines (34 loc) · 1.05 KB
/
writer.go
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// Copyright (C) 2017 Google Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package memory
import (
"fmt"
"io"
)
// Writer returns a binary writer for the specified memory pool and range.
func Writer(p *Pool, rng Range) io.Writer {
b := make([]byte, rng.Size)
p.Write(rng.Base, Blob(b))
w := writer(b)
return &w
}
type writer []byte
func (w *writer) Write(p []byte) (n int, err error) {
n = copy(*w, p)
if n < len(p) {
err = fmt.Errorf("Write overflowed buffer (buffer len: %v, data len: %v)", len(*w), len(p))
}
*w = (*w)[n:]
return
}