diff options
Diffstat (limited to 'vendor/go.uber.org/automaxprocs/internal/cgroups/cgroup.go')
-rw-r--r-- | vendor/go.uber.org/automaxprocs/internal/cgroups/cgroup.go | 79 |
1 files changed, 79 insertions, 0 deletions
diff --git a/vendor/go.uber.org/automaxprocs/internal/cgroups/cgroup.go b/vendor/go.uber.org/automaxprocs/internal/cgroups/cgroup.go new file mode 100644 index 000000000..fe4ecf561 --- /dev/null +++ b/vendor/go.uber.org/automaxprocs/internal/cgroups/cgroup.go @@ -0,0 +1,79 @@ +// Copyright (c) 2017 Uber Technologies, Inc. +// +// Permission is hereby granted, free of charge, to any person obtaining a copy +// of this software and associated documentation files (the "Software"), to deal +// in the Software without restriction, including without limitation the rights +// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell +// copies of the Software, and to permit persons to whom the Software is +// furnished to do so, subject to the following conditions: +// +// The above copyright notice and this permission notice shall be included in +// all copies or substantial portions of the Software. +// +// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN +// THE SOFTWARE. + +//go:build linux +// +build linux + +package cgroups + +import ( + "bufio" + "io" + "os" + "path/filepath" + "strconv" +) + +// CGroup represents the data structure for a Linux control group. +type CGroup struct { + path string +} + +// NewCGroup returns a new *CGroup from a given path. +func NewCGroup(path string) *CGroup { + return &CGroup{path: path} +} + +// Path returns the path of the CGroup*. +func (cg *CGroup) Path() string { + return cg.path +} + +// ParamPath returns the path of the given cgroup param under itself. +func (cg *CGroup) ParamPath(param string) string { + return filepath.Join(cg.path, param) +} + +// readFirstLine reads the first line from a cgroup param file. +func (cg *CGroup) readFirstLine(param string) (string, error) { + paramFile, err := os.Open(cg.ParamPath(param)) + if err != nil { + return "", err + } + defer paramFile.Close() + + scanner := bufio.NewScanner(paramFile) + if scanner.Scan() { + return scanner.Text(), nil + } + if err := scanner.Err(); err != nil { + return "", err + } + return "", io.ErrUnexpectedEOF +} + +// readInt parses the first line from a cgroup param file as int. +func (cg *CGroup) readInt(param string) (int, error) { + text, err := cg.readFirstLine(param) + if err != nil { + return 0, err + } + return strconv.Atoi(text) +} |