diff options
Diffstat (limited to 'vendor/github.com/prometheus/procfs/proc_fdinfo.go')
-rw-r--r-- | vendor/github.com/prometheus/procfs/proc_fdinfo.go | 132 |
1 files changed, 132 insertions, 0 deletions
diff --git a/vendor/github.com/prometheus/procfs/proc_fdinfo.go b/vendor/github.com/prometheus/procfs/proc_fdinfo.go new file mode 100644 index 000000000..83b67d1bd --- /dev/null +++ b/vendor/github.com/prometheus/procfs/proc_fdinfo.go @@ -0,0 +1,132 @@ +// Copyright 2019 The Prometheus 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. + +package procfs + +import ( + "bufio" + "fmt" + "io/ioutil" + "os" + "regexp" + "strings" +) + +// Regexp variables +var ( + rPos = regexp.MustCompile(`^pos:\s+(\d+)$`) + rFlags = regexp.MustCompile(`^flags:\s+(\d+)$`) + rMntID = regexp.MustCompile(`^mnt_id:\s+(\d+)$`) + rInotify = regexp.MustCompile(`^inotify`) +) + +// ProcFDInfo contains represents file descriptor information. +type ProcFDInfo struct { + // File descriptor + FD string + // File offset + Pos string + // File access mode and status flags + Flags string + // Mount point ID + MntID string + // List of inotify lines (structed) in the fdinfo file (kernel 3.8+ only) + InotifyInfos []InotifyInfo +} + +// FDInfo constructor. On kernels older than 3.8, InotifyInfos will always be empty. +func (p Proc) FDInfo(fd string) (*ProcFDInfo, error) { + f, err := os.Open(p.path("fdinfo", fd)) + if err != nil { + return nil, err + } + defer f.Close() + + fdinfo, err := ioutil.ReadAll(f) + if err != nil { + return nil, fmt.Errorf("could not read %s: %s", f.Name(), err) + } + + var text, pos, flags, mntid string + var inotify []InotifyInfo + + scanner := bufio.NewScanner(strings.NewReader(string(fdinfo))) + for scanner.Scan() { + text = scanner.Text() + if rPos.MatchString(text) { + pos = rPos.FindStringSubmatch(text)[1] + } else if rFlags.MatchString(text) { + flags = rFlags.FindStringSubmatch(text)[1] + } else if rMntID.MatchString(text) { + mntid = rMntID.FindStringSubmatch(text)[1] + } else if rInotify.MatchString(text) { + newInotify, err := parseInotifyInfo(text) + if err != nil { + return nil, err + } + inotify = append(inotify, *newInotify) + } + } + + i := &ProcFDInfo{ + FD: fd, + Pos: pos, + Flags: flags, + MntID: mntid, + InotifyInfos: inotify, + } + + return i, nil +} + +// InotifyInfo represents a single inotify line in the fdinfo file. +type InotifyInfo struct { + // Watch descriptor number + WD string + // Inode number + Ino string + // Device ID + Sdev string + // Mask of events being monitored + Mask string +} + +// InotifyInfo constructor. Only available on kernel 3.8+. +func parseInotifyInfo(line string) (*InotifyInfo, error) { + r := regexp.MustCompile(`^inotify\s+wd:([0-9a-f]+)\s+ino:([0-9a-f]+)\s+sdev:([0-9a-f]+)\s+mask:([0-9a-f]+)`) + m := r.FindStringSubmatch(line) + i := &InotifyInfo{ + WD: m[1], + Ino: m[2], + Sdev: m[3], + Mask: m[4], + } + return i, nil +} + +// ProcFDInfos represents a list of ProcFDInfo structs. +type ProcFDInfos []ProcFDInfo + +func (p ProcFDInfos) Len() int { return len(p) } +func (p ProcFDInfos) Swap(i, j int) { p[i], p[j] = p[j], p[i] } +func (p ProcFDInfos) Less(i, j int) bool { return p[i].FD < p[j].FD } + +// InotifyWatchLen returns the total number of inotify watches +func (p ProcFDInfos) InotifyWatchLen() (int, error) { + length := 0 + for _, f := range p { + length += len(f.InotifyInfos) + } + + return length, nil +} |