80 lines
2.9 KiB
Go
80 lines
2.9 KiB
Go
// Copyright 2018 The gVisor Authors.
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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package dev
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import (
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"gvisor.dev/gvisor/pkg/abi/linux"
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"gvisor.dev/gvisor/pkg/context"
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"gvisor.dev/gvisor/pkg/rand"
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"gvisor.dev/gvisor/pkg/safemem"
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"gvisor.dev/gvisor/pkg/sentry/fs"
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"gvisor.dev/gvisor/pkg/sentry/fs/fsutil"
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"gvisor.dev/gvisor/pkg/usermem"
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"gvisor.dev/gvisor/pkg/waiter"
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)
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// +stateify savable
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type randomDevice struct {
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fsutil.InodeGenericChecker `state:"nosave"`
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fsutil.InodeNoExtendedAttributes `state:"nosave"`
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fsutil.InodeNoopAllocate `state:"nosave"`
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fsutil.InodeNoopRelease `state:"nosave"`
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fsutil.InodeNoopTruncate `state:"nosave"`
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fsutil.InodeNoopWriteOut `state:"nosave"`
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fsutil.InodeNotDirectory `state:"nosave"`
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fsutil.InodeNotMappable `state:"nosave"`
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fsutil.InodeNotSocket `state:"nosave"`
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fsutil.InodeNotSymlink `state:"nosave"`
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fsutil.InodeVirtual `state:"nosave"`
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fsutil.InodeSimpleAttributes
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}
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var _ fs.InodeOperations = (*randomDevice)(nil)
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func newRandomDevice(ctx context.Context, owner fs.FileOwner, mode linux.FileMode) *randomDevice {
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r := &randomDevice{
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InodeSimpleAttributes: fsutil.NewInodeSimpleAttributes(ctx, owner, fs.FilePermsFromMode(mode), linux.TMPFS_MAGIC),
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}
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return r
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}
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// GetFile implements fs.InodeOperations.GetFile.
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func (*randomDevice) GetFile(ctx context.Context, dirent *fs.Dirent, flags fs.FileFlags) (*fs.File, error) {
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return fs.NewFile(ctx, dirent, flags, &randomFileOperations{}), nil
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}
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// +stateify savable
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type randomFileOperations struct {
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fsutil.FileGenericSeek `state:"nosave"`
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fsutil.FileNoIoctl `state:"nosave"`
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fsutil.FileNoMMap `state:"nosave"`
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fsutil.FileNoSplice `state:"nosave"`
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fsutil.FileNoopFlush `state:"nosave"`
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fsutil.FileNoopFsync `state:"nosave"`
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fsutil.FileNoopRelease `state:"nosave"`
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fsutil.FileNoopWrite `state:"nosave"`
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fsutil.FileNotDirReaddir `state:"nosave"`
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fsutil.FileUseInodeUnstableAttr `state:"nosave"`
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waiter.AlwaysReady `state:"nosave"`
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}
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var _ fs.FileOperations = (*randomFileOperations)(nil)
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// Read implements fs.FileOperations.Read.
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func (*randomFileOperations) Read(ctx context.Context, _ *fs.File, dst usermem.IOSequence, _ int64) (int64, error) {
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return dst.CopyOutFrom(ctx, safemem.FromIOReader{rand.Reader})
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}
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