| 1 | /* |
| 2 | * Copyright (C) 2015, EfficiOS Inc., Alexandre Montplaisir <alexmonthy@efficios.com> |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or modify |
| 5 | * it under the terms of the GNU General Public License as published by |
| 6 | * the Free Software Foundation; either version 2 of the License, or |
| 7 | * (at your option) any later version. |
| 8 | * |
| 9 | * This program is distributed in the hope that it will be useful, |
| 10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 12 | * GNU General Public License for more details. |
| 13 | * |
| 14 | * You should have received a copy of the GNU General Public License along |
| 15 | * with this program; if not, write to the Free Software Foundation, Inc., |
| 16 | * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
| 17 | */ |
| 18 | |
| 19 | package org.lttng.ust.agent.utils; |
| 20 | |
| 21 | import java.io.IOException; |
| 22 | import java.lang.ProcessBuilder.Redirect; |
| 23 | import java.nio.file.FileVisitResult; |
| 24 | import java.nio.file.Files; |
| 25 | import java.nio.file.Path; |
| 26 | import java.nio.file.Paths; |
| 27 | import java.nio.file.SimpleFileVisitor; |
| 28 | import java.nio.file.attribute.BasicFileAttributes; |
| 29 | import java.util.Arrays; |
| 30 | import java.util.List; |
| 31 | import java.util.UUID; |
| 32 | import java.util.stream.Collectors; |
| 33 | |
| 34 | public class LttngSession implements AutoCloseable { |
| 35 | |
| 36 | public enum Domain { |
| 37 | JUL("-j"), |
| 38 | LOG4J("-l"); |
| 39 | |
| 40 | private final String flag; |
| 41 | |
| 42 | private Domain(String flag) { |
| 43 | this.flag = flag; |
| 44 | } |
| 45 | |
| 46 | public String flag() { |
| 47 | return flag; |
| 48 | } |
| 49 | } |
| 50 | |
| 51 | private final String sessionName; |
| 52 | private final Domain domain; |
| 53 | |
| 54 | private volatile boolean channelCreated = false; |
| 55 | |
| 56 | public LttngSession(String sessionName, Domain domain) { |
| 57 | if (sessionName != null) { |
| 58 | this.sessionName = sessionName; |
| 59 | } else { |
| 60 | this.sessionName = UUID.randomUUID().toString(); |
| 61 | } |
| 62 | this.domain = domain; |
| 63 | |
| 64 | /* Create the session in LTTng */ |
| 65 | executeCommand(Arrays.asList("lttng", "create", this.sessionName)); |
| 66 | } |
| 67 | |
| 68 | @Override |
| 69 | public void close() { |
| 70 | /* Destroy the session */ |
| 71 | executeCommand(Arrays.asList("lttng", "destroy", sessionName)); |
| 72 | // FIXME also delete the trace we generated ? |
| 73 | } |
| 74 | |
| 75 | // ------------------------------------------------------------------------ |
| 76 | // Public methods |
| 77 | // ------------------------------------------------------------------------ |
| 78 | |
| 79 | /** |
| 80 | * Enable all events in the given session (enable-event -a) |
| 81 | * |
| 82 | * @return If the command executed successfully (return code = 0). |
| 83 | */ |
| 84 | public boolean enableAllEvents() { |
| 85 | channelCreated = true; |
| 86 | return executeCommand(Arrays.asList( |
| 87 | "lttng", "enable-event", domain.flag(), "-a", "-s", sessionName)); |
| 88 | } |
| 89 | |
| 90 | /** |
| 91 | * Enable individual event(s). |
| 92 | * |
| 93 | * @param enabledEvents |
| 94 | * The list of events to enable. Should not be null or empty |
| 95 | * @return If the command executed successfully (return code = 0). |
| 96 | */ |
| 97 | public boolean enableEvents(String... enabledEvents) { |
| 98 | if (enabledEvents == null || enabledEvents.length == 0) { |
| 99 | throw new IllegalArgumentException(); |
| 100 | } |
| 101 | channelCreated = true; |
| 102 | return executeCommand(Arrays.asList( |
| 103 | "lttng", "enable-event", domain.flag(), |
| 104 | Arrays.stream(enabledEvents).collect(Collectors.joining(",")), |
| 105 | "-s", sessionName)); |
| 106 | } |
| 107 | |
| 108 | /** |
| 109 | * Send a disable-event command. Used to disable events that were previously |
| 110 | * enabled. |
| 111 | * |
| 112 | * @param disabledEvents |
| 113 | * The list of disabled events. Should not be null or empty |
| 114 | * @return If the command executed successfully (return code = 0). |
| 115 | */ |
| 116 | public boolean disableEvents(String... disabledEvents) { |
| 117 | if (disabledEvents == null || disabledEvents.length == 0) { |
| 118 | throw new IllegalArgumentException(); |
| 119 | } |
| 120 | return executeCommand(Arrays.asList( |
| 121 | "lttng", "disable-event", domain.flag(), |
| 122 | Arrays.stream(disabledEvents).collect(Collectors.joining(",")), |
| 123 | "-s", sessionName)); |
| 124 | } |
| 125 | |
| 126 | public boolean start() { |
| 127 | /* |
| 128 | * We have to enable a channel for 'lttng start' to work. However, we |
| 129 | * cannot enable a channel directly, see |
| 130 | * https://bugs.lttng.org/issues/894 . Instead we will enable an event |
| 131 | * we know does not exist |
| 132 | */ |
| 133 | if (!channelCreated) { |
| 134 | enableEvents("non-event"); |
| 135 | } |
| 136 | return executeCommand(Arrays.asList("lttng", "start", sessionName)); |
| 137 | } |
| 138 | |
| 139 | /** |
| 140 | * Stop the tracing session |
| 141 | * |
| 142 | * @return If the command executed successfully (return code = 0). |
| 143 | */ |
| 144 | public boolean stop() { |
| 145 | return executeCommand(Arrays.asList("lttng", "stop", sessionName)); |
| 146 | } |
| 147 | |
| 148 | /** |
| 149 | * Issue a "lttng view" command on the session, and returns its output. This |
| 150 | * effectively returns the current content of the trace in text form. |
| 151 | * |
| 152 | * @return The output of Babeltrace on the session's current trace |
| 153 | */ |
| 154 | public List<String> view() { |
| 155 | return MiscTestUtils.getOutputFromCommand(Arrays.asList("lttng", "view", sessionName)); |
| 156 | } |
| 157 | |
| 158 | /** |
| 159 | * Utility method to destroy all existing sessions. Useful when first |
| 160 | * setting up a test to make sure no existing session interferes. |
| 161 | */ |
| 162 | public static void destroyAllSessions() { |
| 163 | executeCommand(Arrays.asList("lttng", "destroy", "-a")); |
| 164 | } |
| 165 | |
| 166 | /** |
| 167 | * Outside of the scope of lttng-tools, but this utility method can be used |
| 168 | * to delete all traces currently under ~/lttng-traces/. This can be used by |
| 169 | * tests to cleanup a trace they have created. |
| 170 | * |
| 171 | * @return True if the command completes successfully, false if there was an |
| 172 | * error. |
| 173 | */ |
| 174 | public static boolean deleteAllTracee() { |
| 175 | String tracesDir = new String(System.getProperty("user.home") + "/lttng-traces/"); |
| 176 | return deleteDirectory(Paths.get(tracesDir)); |
| 177 | } |
| 178 | |
| 179 | // ------------------------------------------------------------------------ |
| 180 | // Private helper methods |
| 181 | // ------------------------------------------------------------------------ |
| 182 | |
| 183 | private static boolean deleteDirectory(Path directory) { |
| 184 | try { |
| 185 | Files.walkFileTree(directory, new SimpleFileVisitor<Path>() { |
| 186 | @Override |
| 187 | public FileVisitResult visitFile(Path file, BasicFileAttributes attrs) throws IOException { |
| 188 | Files.delete(file); |
| 189 | return FileVisitResult.CONTINUE; |
| 190 | } |
| 191 | |
| 192 | @Override |
| 193 | public FileVisitResult postVisitDirectory(Path dir, IOException exc) throws IOException { |
| 194 | Files.delete(dir); |
| 195 | return FileVisitResult.CONTINUE; |
| 196 | } |
| 197 | }); |
| 198 | } catch (IOException e) { |
| 199 | /* At least we tried... */ |
| 200 | return false; |
| 201 | } |
| 202 | return true; |
| 203 | } |
| 204 | |
| 205 | /** |
| 206 | * Just to test the environment / stdout are working correctly |
| 207 | */ |
| 208 | public static void main(String[] args) { |
| 209 | List<String> command = Arrays.asList("ls", "-l"); |
| 210 | executeCommand(command); |
| 211 | } |
| 212 | |
| 213 | private static boolean executeCommand(List<String> command) { |
| 214 | try { |
| 215 | ProcessBuilder builder = new ProcessBuilder(command); |
| 216 | builder.redirectErrorStream(true); |
| 217 | builder.redirectOutput(Redirect.INHERIT); |
| 218 | |
| 219 | Process p = builder.start(); |
| 220 | int ret = p.waitFor(); |
| 221 | return (ret == 0); |
| 222 | |
| 223 | } catch (IOException | InterruptedException e) { |
| 224 | return false; |
| 225 | } |
| 226 | } |
| 227 | } |