summaryrefslogtreecommitdiffhomepage
path: root/pkg/sentry/kernel/pipe/buffer.go
diff options
context:
space:
mode:
Diffstat (limited to 'pkg/sentry/kernel/pipe/buffer.go')
-rw-r--r--pkg/sentry/kernel/pipe/buffer.go115
1 files changed, 0 insertions, 115 deletions
diff --git a/pkg/sentry/kernel/pipe/buffer.go b/pkg/sentry/kernel/pipe/buffer.go
deleted file mode 100644
index 95bee2d37..000000000
--- a/pkg/sentry/kernel/pipe/buffer.go
+++ /dev/null
@@ -1,115 +0,0 @@
-// Copyright 2018 The gVisor Authors.
-//
-// 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 pipe
-
-import (
- "io"
- "sync"
-
- "gvisor.dev/gvisor/pkg/sentry/safemem"
-)
-
-// buffer encapsulates a queueable byte buffer.
-//
-// Note that the total size is slightly less than two pages. This
-// is done intentionally to ensure that the buffer object aligns
-// with runtime internals. We have no hard size or alignment
-// requirements. This two page size will effectively minimize
-// internal fragmentation, but still have a large enough chunk
-// to limit excessive segmentation.
-//
-// +stateify savable
-type buffer struct {
- data [8144]byte
- read int
- write int
- bufferEntry
-}
-
-// Reset resets internal data.
-//
-// This must be called before use.
-func (b *buffer) Reset() {
- b.read = 0
- b.write = 0
-}
-
-// Empty indicates the buffer is empty.
-//
-// This indicates there is no data left to read.
-func (b *buffer) Empty() bool {
- return b.read == b.write
-}
-
-// Full indicates the buffer is full.
-//
-// This indicates there is no capacity left to write.
-func (b *buffer) Full() bool {
- return b.write == len(b.data)
-}
-
-// WriteFromBlocks implements safemem.Writer.WriteFromBlocks.
-func (b *buffer) WriteFromBlocks(srcs safemem.BlockSeq) (uint64, error) {
- dst := safemem.BlockSeqOf(safemem.BlockFromSafeSlice(b.data[b.write:]))
- n, err := safemem.CopySeq(dst, srcs)
- b.write += int(n)
- return n, err
-}
-
-// WriteFromReader writes to the buffer from an io.Reader.
-func (b *buffer) WriteFromReader(r io.Reader, count int64) (int64, error) {
- dst := b.data[b.write:]
- if count < int64(len(dst)) {
- dst = b.data[b.write:][:count]
- }
- n, err := r.Read(dst)
- b.write += n
- return int64(n), err
-}
-
-// ReadToBlocks implements safemem.Reader.ReadToBlocks.
-func (b *buffer) ReadToBlocks(dsts safemem.BlockSeq) (uint64, error) {
- src := safemem.BlockSeqOf(safemem.BlockFromSafeSlice(b.data[b.read:b.write]))
- n, err := safemem.CopySeq(dsts, src)
- b.read += int(n)
- return n, err
-}
-
-// ReadToWriter reads from the buffer into an io.Writer.
-func (b *buffer) ReadToWriter(w io.Writer, count int64, dup bool) (int64, error) {
- src := b.data[b.read:b.write]
- if count < int64(len(src)) {
- src = b.data[b.read:][:count]
- }
- n, err := w.Write(src)
- if !dup {
- b.read += n
- }
- return int64(n), err
-}
-
-// bufferPool is a pool for buffers.
-var bufferPool = sync.Pool{
- New: func() interface{} {
- return new(buffer)
- },
-}
-
-// newBuffer grabs a new buffer from the pool.
-func newBuffer() *buffer {
- b := bufferPool.Get().(*buffer)
- b.Reset()
- return b
-}