Report "N/A" for memory columns in Linux Task Manager.

base/process_util_linux.cc

 // Copyright (c) 2009 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 "base/process_util.h"
 
 #include <ctype.h>
 #include <dirent.h>
 #include <errno.h>
 #include <fcntl.h>
@@ skipping 244 matching lines @@
 
 // Private and Shared working set sizes are obtained from /proc/<pid>/smaps,
 // as in http://www.pixelbeat.org/scripts/ps_mem.py
 bool ProcessMetrics::GetWorkingSetKBytes(WorkingSetKBytes* ws_usage) const {
   FilePath stat_file =
     FilePath("/proc").Append(IntToString(process_)).Append("smaps");
   std::string smaps;
   int private_kb = 0;
   int pss_kb = 0;
   bool have_pss = false;
-  if (!file_util::ReadFileToString(stat_file, &smaps))
+  if (!file_util::ReadFileToString(stat_file, &smaps) || smaps.length() == 0)
     return false;
 
   StringTokenizer tokenizer(smaps, ":\n");
   ParsingState state = KEY_NAME;
   std::string last_key_name;
   while (tokenizer.GetNext()) {
     switch (state) {
       case KEY_NAME:
         last_key_name = tokenizer.token();
         state = KEY_VALUE;
@@ skipping 150 matching lines @@
   int percentage = 100 * (cpu - last_cpu_) /
       (kHertz * TimeDelta::FromMicroseconds(time_delta).InSecondsF());
 
   last_time_ = time;
   last_cpu_ = cpu;
 
   return percentage;
 }
 
 }  // namespace base