1 /* 2 * Copyright (c) 2018, 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. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 */ 23 import java.io.BufferedReader; 24 import java.io.File; 25 import java.io.IOException; 26 import java.nio.file.Files; 27 import java.nio.file.Paths; 28 import java.io.FileReader; 29 import java.util.ArrayList; 30 import java.util.Optional; 31 import java.util.List; 32 import java.util.stream.Collectors; 33 import java.util.stream.Stream; 34 import com.oracle.java.testlibrary.Asserts; 35 36 37 // A simple CPU sets reader and parser 38 public class CPUSetsReader { 39 public static String PROC_SELF_STATUS_PATH="/proc/self/status"; 40 41 // Test the parser 42 public static void test() { 43 assertParse("0-7", "0,1,2,3,4,5,6,7"); 44 assertParse("1,3,6", "1,3,6"); 45 assertParse("0,2-4,6,10-11", "0,2,3,4,6,10,11"); 46 assertParse("0", "0"); 47 } 48 49 50 private static void assertParse(String cpuSet, String expectedResult) { 51 Asserts.assertEquals(listToString(parseCpuSet(cpuSet)), expectedResult); 52 } 53 54 55 public static String readFromProcStatus(String setType) { 56 String path = PROC_SELF_STATUS_PATH; 57 Optional<String> o = Optional.empty(); 58 59 System.out.println("readFromProcStatus() entering for: " + setType); 60 61 try (Stream<String> stream = Files.lines(Paths.get(path))) { 62 o = stream 63 .filter(line -> line.contains(setType)) 64 .findFirst(); 65 } catch (IOException e) { 66 return null; 67 } 68 69 if (!o.isPresent()) { 70 return null; // entry not found 71 } 72 73 String[] parts = o.get().replaceAll("\\s","").split(":"); 74 75 // Should be 2 parts, before and after ":" 76 Asserts.assertEquals(parts.length, 2); 77 78 String result = parts[1]; 79 System.out.println("readFromProcStatus() returning: " + result); 80 return result; 81 } 82 83 84 public static List<Integer> parseCpuSet(String value) { 85 ArrayList<Integer> result = new ArrayList<Integer>(); 86 87 try { 88 String[] commaSeparated = value.split(","); 89 90 for (String item : commaSeparated) { 91 if (item.contains("-")) { 92 addRange(result, item); 93 } else { 94 result.add(Integer.parseInt(item)); 95 } 96 } 97 } catch (Exception e) { 98 System.err.println("Exception in getMaxCpuSets(): " + e); 99 return null; 100 } 101 102 return result; 103 } 104 105 106 private static void addRange(ArrayList<Integer> list, String s) { 107 String[] range = s.split("-"); 108 if ( range.length != 2 ) { 109 throw new RuntimeException("Range should only contain two items, but contains " 110 + range.length + " items"); 111 } 112 113 int min = Integer.parseInt(range[0]); 114 int max = Integer.parseInt(range[1]); 115 116 if (min >= max) { 117 String msg = String.format("min is greater or equals to max, min = %d, max = %d", 118 min, max); 119 throw new RuntimeException(msg); 120 } 121 122 for (int i = min; i <= max; i++) { 123 list.add(i); 124 } 125 } 126 127 128 // Convert list of integers to string with comma-separated values 129 public static String listToString(List<Integer> list) { 130 return listToString(list, Integer.MAX_VALUE); 131 } 132 133 // Convert list of integers to a string with comma-separated values; 134 // include up to maxCount. 135 public static String listToString(List<Integer> list, int maxCount) { 136 return list.stream() 137 .limit(maxCount) 138 .map(Object::toString) 139 .collect(Collectors.joining(",")); 140 } 141 }