Move system.* family of APIs to extensions/

chrome/browser/extensions/api/system_cpu/cpu_info_provider_linux.cc

-// Copyright 2014 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "chrome/browser/extensions/api/system_cpu/cpu_info_provider.h"
-
-#include <cstdio>
-#include <sstream>
-
-#include "base/files/file_util.h"
-#include "base/format_macros.h"
-
-namespace extensions {
-
-namespace {
-
-const char kProcStat[] = "/proc/stat";
-
-}  // namespace
-
-bool CpuInfoProvider::QueryCpuTimePerProcessor(
-    std::vector<linked_ptr<api::system_cpu::ProcessorInfo> >* infos) {
-  DCHECK(infos);
-
-  // WARNING: this method may return incomplete data because some processors may
-  // be brought offline at runtime. /proc/stat does not report statistics of
-  // offline processors. CPU usages of offline processors will be filled with
-  // zeros.
-  //
-  // An example of output of /proc/stat when processor 0 and 3 are online, but
-  // processor 1 and 2 are offline:
-  //
-  //   cpu  145292 20018 83444 1485410 995 44 3578 0 0 0
-  //   cpu0 138060 19947 78350 1479514 570 44 3576 0 0 0
-  //   cpu3 2033 32 1075 1400 52 0 1 0 0 0
-  std::string contents;
-  if (!base::ReadFileToString(base::FilePath(kProcStat), &contents))
-     return false;
-
-  std::istringstream iss(contents);
-  std::string line;
-
-  // Skip the first line because it is just an aggregated number of
-  // all cpuN lines.
-  std::getline(iss, line);
-  while (std::getline(iss, line)) {
-    if (line.compare(0, 3, "cpu") != 0)
-      continue;
-
-    uint64 user = 0, nice = 0, sys = 0, idle = 0;
-    uint32 pindex = 0;
-    int vals = sscanf(line.c_str(),
-           "cpu%" PRIu32 " %" PRIu64 " %" PRIu64 " %" PRIu64 " %" PRIu64,
-           &pindex, &user, &nice, &sys, &idle);
-    if (vals != 5 || pindex >= infos->size()) {
-      NOTREACHED();
-      return false;
-    }
-
-    infos->at(pindex)->usage.kernel = static_cast<double>(sys);
-    infos->at(pindex)->usage.user = static_cast<double>(user + nice);
-    infos->at(pindex)->usage.idle = static_cast<double>(idle);
-    infos->at(pindex)->usage.total = static_cast<double>(sys + user +
-                                                         nice + idle);
-  }
-
-  return true;
-}
-
-}  // namespace extensions