| package procfs |
| |
| /* |
| Copyright 2015 The Kubernetes Authors. |
| |
| Licensed under the Apache License, Version 2.0 (the "License"); |
| you may not use this file except in compliance with the License. |
| You may obtain a copy of the License at |
| |
| http://www.apache.org/licenses/LICENSE-2.0 |
| |
| Unless required by applicable law or agreed to in writing, software |
| distributed under the License is distributed on an "AS IS" BASIS, |
| WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| See the License for the specific language governing permissions and |
| limitations under the License. |
| */ |
| |
| import ( |
| "bytes" |
| "fmt" |
| "io" |
| "io/ioutil" |
| "os" |
| "path/filepath" |
| "regexp" |
| "strconv" |
| "strings" |
| "unicode" |
| |
| "github.com/sirupsen/logrus" |
| ) |
| |
| // PidOf finds process(es) with a specified name (regexp match) |
| // and return their pid(s) |
| func PidOf(name string) ([]int, error) { |
| if len(name) == 0 { |
| return []int{}, fmt.Errorf("name should not be empty") |
| } |
| re, err := regexp.Compile("(^|/)" + name + "$") |
| if err != nil { |
| return []int{}, err |
| } |
| return getPids(re), nil |
| } |
| |
| func getPids(re *regexp.Regexp) []int { |
| pids := []int{} |
| |
| dirFD, err := os.Open("/proc") |
| if err != nil { |
| return nil |
| } |
| defer dirFD.Close() |
| |
| for { |
| // Read a small number at a time in case there are many entries, we don't want to |
| // allocate a lot here. |
| ls, err := dirFD.Readdir(10) |
| if err == io.EOF { |
| break |
| } |
| if err != nil { |
| return nil |
| } |
| |
| for _, entry := range ls { |
| if !entry.IsDir() { |
| continue |
| } |
| |
| // If the directory is not a number (i.e. not a PID), skip it |
| pid, err := strconv.Atoi(entry.Name()) |
| if err != nil { |
| continue |
| } |
| |
| cmdline, err := ioutil.ReadFile(filepath.Join("/proc", entry.Name(), "cmdline")) |
| if err != nil { |
| logrus.Infof("Error reading file %s: %+v", filepath.Join("/proc", entry.Name(), "cmdline"), err) |
| continue |
| } |
| |
| // The bytes we read have '\0' as a separator for the command line |
| parts := bytes.SplitN(cmdline, []byte{0}, 2) |
| if len(parts) == 0 { |
| continue |
| } |
| // Split the command line itself we are interested in just the first part |
| exe := strings.FieldsFunc(string(parts[0]), func(c rune) bool { |
| return unicode.IsSpace(c) || c == ':' |
| }) |
| if len(exe) == 0 { |
| continue |
| } |
| // Check if the name of the executable is what we are looking for |
| if re.MatchString(exe[0]) { |
| // Grab the PID from the directory path |
| pids = append(pids, pid) |
| } |
| } |
| } |
| |
| return pids |
| } |