Tumortisch-Dist/resources/app/node_modules/pidusage/lib/procfile.js
2021-06-15 16:00:08 +02:00

142 lines
3.7 KiB
JavaScript

var fs = require('fs')
var path = require('path')
var updateCpu = require('./helpers/cpu')
var parallel = require('./helpers/parallel')
var history = require('./history')
var cpuInfo = null
var Buffer = require('safe-buffer').Buffer
var SIZE = 1024 // if the stat file is bigger then this I'll buy you a drink
function noop () {}
function open (path, history, cb) {
if (history.fd) { return cb(null, history.fd) }
fs.open(path, 'r', cb)
}
function close (history) {
if (history.fd) {
fs.close(history.fd, noop)
}
}
function readUntilEnd (fd, buf, cb) {
var firstRead = false
if (typeof buf === 'function') {
cb = buf
buf = Buffer.alloc(SIZE)
firstRead = true
}
fs.read(fd, buf, 0, SIZE, 0, function (err, bytesRead, buffer) {
if (err) {
cb(err)
return
}
var data = Buffer.concat([buf, buffer], firstRead ? bytesRead : buf.length + bytesRead)
if (bytesRead === SIZE) {
readUntilEnd(fd, data, cb)
return
}
cb(null, buf)
})
}
function readProcFile (pid, options, done) {
var hst = history.get(pid, options.maxage)
var again = false
if (hst === undefined) {
again = true
hst = {}
}
// Arguments to path.join must be strings
open(path.join('/proc', '' + pid, 'stat'), hst, function (err, fd) {
if (err) {
if (err.code === 'ENOENT') {
err.message = 'No maching pid found'
}
return done(err, null)
}
if (err) {
return done(err)
}
readUntilEnd(fd, function (err, buffer) {
if (err) {
return done(err)
}
var infos = buffer.toString('utf8')
var date = Date.now()
// https://github.com/arunoda/node-usage/commit/a6ca74ecb8dd452c3c00ed2bde93294d7bb75aa8
// preventing process space in name by removing values before last ) (pid (name) ...)
var index = infos.lastIndexOf(')')
infos = infos.substr(index + 2).split(' ')
// according to http://man7.org/linux/man-pages/man5/proc.5.html (index 0 based - 2)
// In kernels before Linux 2.6, start was expressed in jiffies. Since Linux 2.6, the value is expressed in clock ticks
var stat = {
ppid: parseInt(infos[1]),
utime: parseFloat(infos[11]),
stime: parseFloat(infos[12]),
cutime: parseFloat(infos[13]),
cstime: parseFloat(infos[14]),
start: parseFloat(infos[19]) / cpuInfo.clockTick,
rss: parseFloat(infos[21]),
uptime: cpuInfo.uptime,
fd: fd
}
var memory = stat.rss * cpuInfo.pageSize
// https://stackoverflow.com/a/16736599/3921589
var childrens = options.childrens ? stat.cutime + stat.cstime : 0
// process usage since last call in seconds
var total = (stat.stime - (hst.stime || 0) + stat.utime - (hst.utime || 0) + childrens) / cpuInfo.clockTick
// time elapsed between calls in seconds
var seconds = Math.abs(hst.uptime !== undefined ? stat.uptime - hst.uptime : stat.start - stat.uptime)
var cpu = seconds > 0 ? (total / seconds) * 100 : 0
history.set(pid, stat, options.maxage, close)
if (again) {
return readProcFile(pid, options, done)
}
return done(null, {
cpu: cpu,
memory: memory,
ctime: (stat.utime + stat.stime) / cpuInfo.clockTick,
elapsed: date - (stat.start * 1000),
timestamp: stat.start * 1000, // start date
pid: pid,
ppid: stat.ppid
})
})
})
}
function procfile (pids, options, done) {
updateCpu(cpuInfo, function (err, result) {
if (err) return done(err)
cpuInfo = result
var fns = {}
pids.forEach(function (pid, i) {
fns[pid] = function (cb) {
readProcFile(pid, options, cb)
}
})
parallel(fns, {graceful: true}, done)
})
}
module.exports = procfile