feat: 초기 프로젝트 설정 및 룰.md 파일 추가

api.hyungi.net/node_modules/pidusage/lib/procfile.js

@@ -0,0 +1,141 @@
+const fs = require('fs')
+const path = require('path')
+const updateCpu = require('./helpers/cpu')
+const parallel = require('./helpers/parallel')
+const history = require('./history')
+let cpuInfo = null
+const Buffer = require('safe-buffer').Buffer
+const 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) {
+  let 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
+    }
+
+    const 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) {
+  let hst = history.get(pid, options.maxage)
+  let 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 matching pid found'
+      }
+      return done(err, null)
+    }
+
+    if (err) {
+      return done(err)
+    }
+
+    readUntilEnd(fd, function (err, buffer) {
+      if (err) {
+        return done(err)
+      }
+
+      let infos = buffer.toString('utf8')
+      const date = Date.now()
+
+      // https://github.com/arunoda/node-usage/commit/a6ca74ecb8dd452c3c00ed2bde93294d7bb75aa8
+      // preventing process space in name by removing values before last ) (pid (name) ...)
+      const 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
+      const stat = {
+        ppid: parseInt(infos[1]),
+        utime: parseFloat(infos[11]) * 1000 / cpuInfo.clockTick,
+        stime: parseFloat(infos[12]) * 1000 / cpuInfo.clockTick,
+        cutime: parseFloat(infos[13]) * 1000 / cpuInfo.clockTick,
+        cstime: parseFloat(infos[14]) * 1000 / cpuInfo.clockTick,
+        start: parseFloat(infos[19]) * 1000 / cpuInfo.clockTick,
+        rss: parseFloat(infos[21]),
+        uptime: cpuInfo.uptime * 1000,
+        fd: fd
+      }
+
+      const memory = stat.rss * cpuInfo.pageSize
+
+      // https://stackoverflow.com/a/16736599/3921589
+      const childrens = options.childrens ? stat.cutime + stat.cstime : 0
+      // process usage since last call in seconds
+      const total = (stat.stime - (hst.stime || 0) + stat.utime - (hst.utime || 0) + childrens)
+      // time elapsed between calls in seconds
+      const seconds = Math.abs(hst.uptime !== undefined ? stat.uptime - hst.uptime : stat.start - stat.uptime)
+      const 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,
+        elapsed: stat.uptime - stat.start,
+        timestamp: date,
+        pid: pid,
+        ppid: stat.ppid
+      })
+    })
+  })
+}
+
+function procfile (pids, options, done) {
+  updateCpu(cpuInfo, function (err, result) {
+    if (err) return done(err)
+
+    cpuInfo = result
+    const fns = {}
+
+    pids.forEach(function (pid, i) {
+      fns[pid] = function (cb) {
+        readProcFile(pid, options, cb)
+      }
+    })
+
+    parallel(fns, { graceful: true }, done)
+  })
+}
+
+module.exports = procfile