67 lines
2.1 KiB
Go
67 lines
2.1 KiB
Go
// Copyright 2020 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 host
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import (
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"syscall"
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"golang.org/x/sys/unix"
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"gvisor.dev/gvisor/pkg/abi/linux"
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"gvisor.dev/gvisor/pkg/syserror"
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)
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func toTimespec(ts linux.StatxTimestamp, omit bool) unix.Timespec {
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if omit {
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return unix.Timespec{
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Sec: 0,
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Nsec: unix.UTIME_OMIT,
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}
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}
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return unix.Timespec{
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Sec: int64(ts.Sec),
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Nsec: int64(ts.Nsec),
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}
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}
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func unixToLinuxStatxTimestamp(ts unix.StatxTimestamp) linux.StatxTimestamp {
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return linux.StatxTimestamp{Sec: ts.Sec, Nsec: ts.Nsec}
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}
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func timespecToStatxTimestamp(ts unix.Timespec) linux.StatxTimestamp {
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return linux.StatxTimestamp{Sec: int64(ts.Sec), Nsec: uint32(ts.Nsec)}
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}
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// wouldBlock returns true for file types that can return EWOULDBLOCK
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// for blocking operations, e.g. pipes, character devices, and sockets.
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func wouldBlock(fileType uint32) bool {
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return fileType == syscall.S_IFIFO || fileType == syscall.S_IFCHR || fileType == syscall.S_IFSOCK
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}
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// canMap returns true if a file with fileType is allowed to be memory mapped.
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// This is ported over from VFS1, but it's probably not the best way for us
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// to check if a file can be memory mapped.
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func canMap(fileType uint32) bool {
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// TODO(gvisor.dev/issue/1672): Also allow "special files" to be mapped (see fs/host:canMap()).
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//
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// TODO(b/38213152): Some obscure character devices can be mapped.
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return fileType == syscall.S_IFREG
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}
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// isBlockError checks if an error is EAGAIN or EWOULDBLOCK.
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// If so, they can be transformed into syserror.ErrWouldBlock.
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func isBlockError(err error) bool {
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return err == syserror.EAGAIN || err == syserror.EWOULDBLOCK
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}
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