github.com/MerlinKodo/gvisor@v0.0.0-20231110090155-957f62ecf90e/pkg/shim/runsc/utils.go (about)

     1  // Copyright 2018 The containerd Authors.
     2  // Copyright 2018 The gVisor Authors.
     3  //
     4  // Licensed under the Apache License, Version 2.0 (the "License");
     5  // you may not use this file except in compliance with the License.
     6  // You may obtain a copy of the License at
     7  //
     8  //     https://www.apache.org/licenses/LICENSE-2.0
     9  //
    10  // Unless required by applicable law or agreed to in writing, software
    11  // distributed under the License is distributed on an "AS IS" BASIS,
    12  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13  // See the License for the specific language governing permissions and
    14  // limitations under the License.
    15  
    16  package runsc
    17  
    18  import (
    19  	"bytes"
    20  	"strings"
    21  	"sync"
    22  )
    23  
    24  var bytesBufferPool = sync.Pool{
    25  	New: func() any {
    26  		return bytes.NewBuffer(nil)
    27  	},
    28  }
    29  
    30  func getBuf() *bytes.Buffer {
    31  	return bytesBufferPool.Get().(*bytes.Buffer)
    32  }
    33  
    34  func putBuf(b *bytes.Buffer) {
    35  	b.Reset()
    36  	bytesBufferPool.Put(b)
    37  }
    38  
    39  // pathLikeFlags are runsc flags which refer to paths to files.
    40  var pathLikeFlags = []string{
    41  	"log",
    42  	"panic-log",
    43  	"debug-log",
    44  	"coverage-report",
    45  	"profile-block",
    46  	"profile-cpu",
    47  	"profile-heap",
    48  	"profile-mutex",
    49  	"trace",
    50  }
    51  
    52  // replaceID replaces %ID% in `path` with the given sandbox ID.
    53  func replaceID(id string, path string) string {
    54  	return strings.Replace(path, "%ID%", id, -1)
    55  }
    56  
    57  // EmittedPaths returns a list of file paths that the sandbox may need to
    58  // create using the given configuration. Useful to create parent directories.
    59  func EmittedPaths(id string, config map[string]string) []string {
    60  	var paths []string
    61  	for _, cfgFlag := range pathLikeFlags {
    62  		if path, ok := config[cfgFlag]; ok {
    63  			paths = append(paths, replaceID(id, path))
    64  		}
    65  	}
    66  	return paths
    67  }
    68  
    69  // FormatRunscPaths fills in %ID% in path-like flags.
    70  func FormatRunscPaths(id string, config map[string]string) {
    71  	for _, cfgFlag := range pathLikeFlags {
    72  		if path, ok := config[cfgFlag]; ok {
    73  			config[cfgFlag] = replaceID(id, path)
    74  		}
    75  	}
    76  }
    77  
    78  // FormatShimLogPath creates the file path to the log file. It replaces %ID%
    79  // in the path with the provided "id". It also uses a default log name if the
    80  // path ends with '/'.
    81  func FormatShimLogPath(path string, id string) string {
    82  	if strings.HasSuffix(path, "/") {
    83  		// Default format: <path>/runsc-shim-<ID>.log
    84  		path += "runsc-shim-%ID%.log"
    85  	}
    86  	return replaceID(id, path)
    87  }