1 /*
   2  * Copyright (c) 2018, 2020, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package jdk.internal.platform.cgroupv1;
  27 
  28 import jdk.internal.platform.CgroupSubsystem;
  29 import jdk.internal.platform.CgroupSubsystemController;
  30 
  31 public class CgroupV1SubsystemController implements CgroupSubsystemController {
  32 
  33     private static final double DOUBLE_RETVAL_UNLIMITED = CgroupSubsystem.LONG_RETVAL_UNLIMITED;
  34     // Values returned larger than this number are unlimited.
  35     static long UNLIMITED_MIN = 0x7FFFFFFFFF000000L;
  36     String root;
  37     String mountPoint;
  38     String path;
  39 
  40     public CgroupV1SubsystemController(String root, String mountPoint) {
  41         this.root = root;
  42         this.mountPoint = mountPoint;
  43     }
  44 
  45     public void setPath(String cgroupPath) {
  46         if (root != null && cgroupPath != null) {
  47             if (root.equals("/")) {
  48                 if (!cgroupPath.equals("/")) {
  49                     path = mountPoint + cgroupPath;
  50                 }
  51                 else {
  52                     path = mountPoint;
  53                 }
  54             }
  55             else {
  56                 if (root.equals(cgroupPath)) {
  57                     path = mountPoint;
  58                 }
  59                 else {
  60                     if (cgroupPath.startsWith(root)) {
  61                         if (cgroupPath.length() > root.length()) {
  62                             String cgroupSubstr = cgroupPath.substring(root.length());
  63                             path = mountPoint + cgroupSubstr;
  64                         }
  65                     }
  66                 }
  67             }
  68         }
  69     }
  70 
  71     @Override
  72     public String path() {
  73         return path;
  74     }
  75 
  76     public static long getLongEntry(CgroupSubsystemController controller, String param, String entryname) {
  77         return CgroupSubsystemController.getLongEntry(controller,
  78                                                       param,
  79                                                       entryname,
  80                                                       CgroupSubsystem.LONG_RETVAL_UNLIMITED /* retval on error */);
  81     }
  82 
  83     public static double getDoubleValue(CgroupSubsystemController controller, String parm) {
  84         return CgroupSubsystemController.getDoubleValue(controller,
  85                                                         parm,
  86                                                         DOUBLE_RETVAL_UNLIMITED /* retval on error */);
  87     }
  88 
  89     public static long convertStringToLong(String strval) {
  90         return CgroupSubsystemController.convertStringToLong(strval,
  91                                                              Long.MAX_VALUE /* overflow value */,
  92                                                              CgroupSubsystem.LONG_RETVAL_UNLIMITED /* retval on error */);
  93     }
  94 
  95     public static long longValOrUnlimited(long value) {
  96         return value > UNLIMITED_MIN ? CgroupSubsystem.LONG_RETVAL_UNLIMITED : value;
  97     }
  98 
  99     public static long getLongValueMatchingLine(CgroupSubsystemController controller,
 100                                                 String param,
 101                                                 String match) {
 102         return CgroupSubsystemController.getLongValueMatchingLine(controller,
 103                                                                   param,
 104                                                                   match,
 105                                                                   CgroupV1SubsystemController::convertHierachicalLimitLine,
 106                                                                   CgroupSubsystem.LONG_RETVAL_UNLIMITED);
 107     }
 108 
 109     public static long convertHierachicalLimitLine(String line) {
 110         String[] tokens = line.split("\\s");
 111         if (tokens.length == 2) {
 112             String strVal = tokens[1];
 113             return CgroupV1SubsystemController.convertStringToLong(strVal);
 114         }
 115         return CgroupV1SubsystemController.UNLIMITED_MIN + 1; // unlimited
 116     }
 117 
 118 }