mirror of
https://github.com/prometheus/prometheus.git
synced 2024-12-27 14:39:40 -08:00
81c4248081
The goal is to remove almost all references to the golang.org/x/net/context package. github.com/gogo/protobuf => v1.2.1 google.golang.org/grpc => v1.19.1 github.com/grpc-ecosystem/grpc-gateway => v1.18.5 It also replaces github.com/cockroachdb/cmux by github.com/soheilhy/cmux because of [1] which fixes #3909 incidentally. [1] https://github.com/grpc/grpc-go/issues/2636 Signed-off-by: Simon Pasquier <spasquie@redhat.com>
68 lines
2 KiB
Go
68 lines
2 KiB
Go
// Copyright 2016 The CMux Authors. All rights reserved.
|
|
//
|
|
// 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 cmux
|
|
|
|
import (
|
|
"bytes"
|
|
"io"
|
|
)
|
|
|
|
// bufferedReader is an optimized implementation of io.Reader that behaves like
|
|
// ```
|
|
// io.MultiReader(bytes.NewReader(buffer.Bytes()), io.TeeReader(source, buffer))
|
|
// ```
|
|
// without allocating.
|
|
type bufferedReader struct {
|
|
source io.Reader
|
|
buffer bytes.Buffer
|
|
bufferRead int
|
|
bufferSize int
|
|
sniffing bool
|
|
lastErr error
|
|
}
|
|
|
|
func (s *bufferedReader) Read(p []byte) (int, error) {
|
|
if s.bufferSize > s.bufferRead {
|
|
// If we have already read something from the buffer before, we return the
|
|
// same data and the last error if any. We need to immediately return,
|
|
// otherwise we may block for ever, if we try to be smart and call
|
|
// source.Read() seeking a little bit of more data.
|
|
bn := copy(p, s.buffer.Bytes()[s.bufferRead:s.bufferSize])
|
|
s.bufferRead += bn
|
|
return bn, s.lastErr
|
|
} else if !s.sniffing && s.buffer.Cap() != 0 {
|
|
// We don't need the buffer anymore.
|
|
// Reset it to release the internal slice.
|
|
s.buffer = bytes.Buffer{}
|
|
}
|
|
|
|
// If there is nothing more to return in the sniffed buffer, read from the
|
|
// source.
|
|
sn, sErr := s.source.Read(p)
|
|
if sn > 0 && s.sniffing {
|
|
s.lastErr = sErr
|
|
if wn, wErr := s.buffer.Write(p[:sn]); wErr != nil {
|
|
return wn, wErr
|
|
}
|
|
}
|
|
return sn, sErr
|
|
}
|
|
|
|
func (s *bufferedReader) reset(snif bool) {
|
|
s.sniffing = snif
|
|
s.bufferRead = 0
|
|
s.bufferSize = s.buffer.Len()
|
|
}
|