github.com/SagerNet/gvisor@v0.0.0-20210707092255-7731c139d75c/pkg/sentry/fs/gofer/file_state.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  package gofer
    16  
    17  import (
    18  	"fmt"
    19  
    20  	"github.com/SagerNet/gvisor/pkg/context"
    21  	"github.com/SagerNet/gvisor/pkg/sentry/fs"
    22  )
    23  
    24  // afterLoad is invoked by stateify.
    25  func (f *fileOperations) afterLoad() {
    26  	load := func() error {
    27  		f.inodeOperations.fileState.waitForLoad()
    28  
    29  		// Manually load the open handles.
    30  		var err error
    31  
    32  		// The file may have been opened with Truncate, but we don't
    33  		// want to re-open it with Truncate or we will lose data.
    34  		flags := f.flags
    35  		flags.Truncate = false
    36  
    37  		f.handles, err = f.inodeOperations.fileState.getHandles(context.Background(), flags, f.inodeOperations.cachingInodeOps)
    38  		if err != nil {
    39  			return fmt.Errorf("failed to re-open handle: %v", err)
    40  		}
    41  		return nil
    42  	}
    43  	fs.Async(fs.CatchError(load))
    44  }