github.com/SagerNet/gvisor@v0.0.0-20210707092255-7731c139d75c/pkg/syserr/host_linux.go (about)

     1  // Copyright 2018 The gVisor Authors.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  // +build linux
    16  
    17  package syserr
    18  
    19  import (
    20  	"fmt"
    21  
    22  	"golang.org/x/sys/unix"
    23  )
    24  
    25  const maxErrno = 134
    26  
    27  type linuxHostTranslation struct {
    28  	err *Error
    29  	ok  bool
    30  }
    31  
    32  var linuxHostTranslations [maxErrno]linuxHostTranslation
    33  
    34  // FromHost translates a unix.Errno to a corresponding Error value.
    35  func FromHost(err unix.Errno) *Error {
    36  	if int(err) >= len(linuxHostTranslations) || !linuxHostTranslations[err].ok {
    37  		panic(fmt.Sprintf("unknown host errno %q (%d)", err.Error(), err))
    38  	}
    39  	return linuxHostTranslations[err].err
    40  }
    41  
    42  func addLinuxHostTranslation(host unix.Errno, trans *Error) {
    43  	if linuxHostTranslations[host].ok {
    44  		panic(fmt.Sprintf("duplicate translation for host errno %q (%d)", host.Error(), host))
    45  	}
    46  	linuxHostTranslations[host] = linuxHostTranslation{err: trans, ok: true}
    47  }