56 lines
1.5 KiB
Go
56 lines
1.5 KiB
Go
// Copyright 2018 Google Inc.
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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 linux
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import (
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"gvisor.googlesource.com/gvisor/pkg/sentry/arch"
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"gvisor.googlesource.com/gvisor/pkg/sentry/fs"
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"gvisor.googlesource.com/gvisor/pkg/sentry/kernel"
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"gvisor.googlesource.com/gvisor/pkg/sentry/kernel/kdefs"
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"gvisor.googlesource.com/gvisor/pkg/syserror"
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)
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// Lseek implements linux syscall lseek(2).
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func Lseek(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
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fd := kdefs.FD(args[0].Int())
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offset := args[1].Int64()
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whence := args[2].Int()
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file := t.FDMap().GetFile(fd)
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if file == nil {
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return 0, nil, syserror.EBADF
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}
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defer file.DecRef()
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var sw fs.SeekWhence
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switch whence {
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case 0:
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sw = fs.SeekSet
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case 1:
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sw = fs.SeekCurrent
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case 2:
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sw = fs.SeekEnd
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default:
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return 0, nil, syserror.EINVAL
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}
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offset, serr := file.Seek(t, sw, offset)
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err := handleIOError(t, false /* partialResult */, serr, kernel.ERESTARTSYS, "lseek", file)
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if err != nil {
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return 0, nil, err
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}
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return uintptr(offset), nil, err
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}
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