Felipe Leme | f4006d9 | 2016-10-07 17:57:13 -0700 | [diff] [blame] | 1 | /** |
| 2 | * Copyright (c) 2016, The Android Open Source Project |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
| 17 | package com.android.server.utils; |
| 18 | |
| 19 | import java.io.FileDescriptor; |
| 20 | import java.io.PrintWriter; |
| 21 | |
| 22 | /** |
| 23 | * Helper for {@link android.os.Binder#dump(java.io.FileDescriptor, String[])} that supports the |
| 24 | * {@link #PRIORITY_ARG} argument. |
| 25 | * <p> |
| 26 | * Typical usage: |
| 27 | * |
| 28 | * <pre><code> |
| 29 | public class SpringfieldNuclearPowerPlant extends Binder { |
| 30 | |
| 31 | private final PriorityDump.PriorityDumper mPriorityDumper = new PriorityDump.PriorityDumper() { |
| 32 | |
| 33 | @Override |
| 34 | public void dumpCritical(FileDescriptor fd, PrintWriter pw, String[] args) { |
| 35 | pw.println("Donuts in the box: 1"); |
| 36 | } |
| 37 | |
| 38 | @Override |
| 39 | public void dumpNormal(FileDescriptor fd, PrintWriter pw, String[] args) { |
| 40 | pw.println("Nuclear reactor status: DANGER - MELTDOWN IMMINENT"); |
| 41 | } |
| 42 | }; |
| 43 | |
| 44 | @Override |
| 45 | protected void dump(FileDescriptor fd, PrintWriter pw, String[] args) { |
| 46 | PriorityDump.dump(mPriorityDumper, fd, pw, args); |
| 47 | } |
| 48 | } |
| 49 | |
| 50 | * </code></pre> |
| 51 | * |
| 52 | * <strong>Disclaimer</strong>: a real-life service should prioritize core status over donuts :-) |
| 53 | * |
| 54 | * <p>Then to invoke it: |
| 55 | * |
| 56 | * <pre><code> |
| 57 | * |
| 58 | $ adb shell dumpsys snpp |
| 59 | Donuts in the box: 1 |
| 60 | Nuclear reactor status: DANGER - MELTDOWN IMMINENT |
| 61 | |
| 62 | $ adb shell dumpsys snpp --dump_priority CRITICAL |
| 63 | Donuts in the box: 1 |
| 64 | |
| 65 | $ adb shell dumpsys snpp --dump_priority NORMAL |
| 66 | Nuclear reactor status: DANGER - MELTDOWN IMMINENT |
| 67 | |
| 68 | * </code></pre> |
| 69 | * |
| 70 | * |
| 71 | * |
| 72 | * <p>To run the unit tests: |
| 73 | * <pre><code> |
| 74 | * |
| 75 | mmm -j32 frameworks/base/services/tests/servicestests/ && \ |
| 76 | adb install -r -g ${ANDROID_PRODUCT_OUT}/data/app/FrameworksServicesTests/FrameworksServicesTests.apk && \ |
| 77 | adb shell am instrument -e class "com.android.server.utils.PriorityDumpTest" \ |
| 78 | -w "com.android.frameworks.servicestests/android.support.test.runner.AndroidJUnitRunner" |
| 79 | |
| 80 | * </code></pre> |
| 81 | * |
| 82 | * |
| 83 | * @hide |
| 84 | */ |
| 85 | public final class PriorityDump { |
| 86 | |
| 87 | public static final String PRIORITY_ARG = "--dump_priority"; |
| 88 | |
| 89 | private PriorityDump() { |
| 90 | throw new UnsupportedOperationException(); |
| 91 | } |
| 92 | |
| 93 | /** |
| 94 | * Parses {@code} and call the proper {@link PriorityDumper} method when the first argument is |
| 95 | * {@code --dump_priority}, stripping the priority and its type. |
| 96 | * <p> |
| 97 | * For example, if called as {@code --dump_priority HIGH arg1 arg2 arg3}, it will call |
| 98 | * <code>dumper.dumpHigh(fd, pw, {"arg1", "arg2", "arg3"}) </code> |
| 99 | * <p> |
| 100 | * If the {@code --dump_priority} is not set, it calls |
| 101 | * {@link PriorityDumper#dump(FileDescriptor, PrintWriter, String[])} passing the whole |
| 102 | * {@code args} instead. |
| 103 | */ |
| 104 | public static void dump(PriorityDumper dumper, FileDescriptor fd, PrintWriter pw, |
| 105 | String[] args) { |
| 106 | if (args != null && args.length >= 2 && args[0].equals(PRIORITY_ARG)) { |
| 107 | final String priority = args[1]; |
| 108 | switch (priority) { |
| 109 | case "CRITICAL": { |
| 110 | dumper.dumpCritical(fd, pw, getStrippedArgs(args)); |
| 111 | return; |
| 112 | } |
| 113 | case "HIGH": { |
| 114 | dumper.dumpHigh(fd, pw, getStrippedArgs(args)); |
| 115 | return; |
| 116 | } |
| 117 | case "NORMAL": { |
| 118 | dumper.dumpNormal(fd, pw, getStrippedArgs(args)); |
| 119 | return; |
| 120 | } |
| 121 | } |
| 122 | } |
| 123 | dumper.dump(fd, pw, args); |
| 124 | } |
| 125 | |
| 126 | /** |
| 127 | * Gets an array without the {@code --dump_priority PRIORITY} prefix. |
| 128 | */ |
| 129 | private static String[] getStrippedArgs(String[] args) { |
| 130 | final String[] stripped = new String[args.length - 2]; |
| 131 | System.arraycopy(args, 2, stripped, 0, stripped.length); |
| 132 | return stripped; |
| 133 | } |
| 134 | |
| 135 | /** |
| 136 | * Helper for {@link android.os.Binder#dump(java.io.FileDescriptor, String[])} that supports the |
| 137 | * {@link #PRIORITY_ARG} argument. |
| 138 | * |
| 139 | * @hide |
| 140 | */ |
| 141 | public static interface PriorityDumper { |
| 142 | |
| 143 | /** |
| 144 | * Dumps only the critical section. |
| 145 | */ |
| 146 | @SuppressWarnings("unused") |
| 147 | default void dumpCritical(FileDescriptor fd, PrintWriter pw, String[] args) { |
| 148 | } |
| 149 | |
| 150 | /** |
| 151 | * Dumps only the high-priority section. |
| 152 | */ |
| 153 | @SuppressWarnings("unused") |
| 154 | default void dumpHigh(FileDescriptor fd, PrintWriter pw, String[] args) { |
| 155 | } |
| 156 | |
| 157 | /** |
| 158 | * Dumps only the normal section. |
| 159 | */ |
| 160 | @SuppressWarnings("unused") |
| 161 | default void dumpNormal(FileDescriptor fd, PrintWriter pw, String[] args) { |
| 162 | } |
| 163 | |
| 164 | /** |
| 165 | * Dumps all sections. |
| 166 | * <p> |
| 167 | * This method is called when |
| 168 | * {@link PriorityDump#dump(PriorityDumper, FileDescriptor, PrintWriter, String[])} is |
| 169 | * called without priority arguments. By default, it calls the 3 {@code dumpTYPE} methods, |
| 170 | * so sub-classes just need to implement the priority types they support. |
| 171 | */ |
| 172 | @SuppressWarnings("unused") |
| 173 | default void dump(FileDescriptor fd, PrintWriter pw, String[] args) { |
| 174 | dumpCritical(fd, pw, args); |
| 175 | dumpHigh(fd, pw, args); |
| 176 | dumpNormal(fd, pw, args); |
| 177 | } |
| 178 | } |
| 179 | } |