import java.nio.ByteBuffer;
import java.nio.ByteOrder;
+import org.lttng.ust.agent.session.EventRule;
+import org.lttng.ust.agent.session.LogLevelSelector;
+
/**
* Session daemon command indicating to the Java agent that some events were
* enabled in the tracing session.
*/
class SessiondEnableEventCommand implements ISessiondCommand {
- private static final int INT_SIZE = 4;
+ /** Fixed event name length. Value defined by the lttng agent protocol. */
+ private static final int EVENT_NAME_LENGTH = 256;
+
+ private final boolean commandIsValid;
- /** Event name to enable in the tracing session */
+ /* Parameters of the event rule being enabled */
private final String eventName;
+ private final LogLevelSelector logLevelFilter;
+ private final String filterString;
public SessiondEnableEventCommand(byte[] data) {
if (data == null) {
throw new IllegalArgumentException();
}
- int dataOffset = INT_SIZE * 2;
-
ByteBuffer buf = ByteBuffer.wrap(data);
buf.order(ByteOrder.LITTLE_ENDIAN);
- buf.getInt(); // logLevel, currently unused
- buf.getInt(); // logLevelType, currently unused
- eventName = new String(data, dataOffset, data.length - dataOffset).trim();
+ int logLevel = buf.getInt();
+ int logLevelType = buf.getInt();
+ logLevelFilter = new LogLevelSelector(logLevel, logLevelType);
+
+ /* Read the event name */
+ byte[] eventNameBytes = new byte[EVENT_NAME_LENGTH];
+ buf.get(eventNameBytes);
+ eventName = new String(eventNameBytes).trim();
+
+ /*
+ * Read the filter string. The buffer contains the length (number of
+ * bytes), then the bytes themselves.
+ *
+ * The length is represented as an unsigned int, but it should never
+ * be greater than Integer.MAX_VALUE.
+ */
+ int filterStringLength = buf.getInt();
+ if (filterStringLength < 0) {
+ /*
+ * The (unsigned) length is above what the sessiond should send. The
+ * command cannot be processed.
+ */
+ filterString = null;
+ commandIsValid = false;
+ return;
+ }
+ if (filterStringLength == 0) {
+ /* There is explicitly no filter string */
+ filterString = "";
+ commandIsValid = true;
+ return;
+ }
+
+ byte[] filterStringBytes = new byte[filterStringLength];
+ buf.get(filterStringBytes);
+ filterString = new String(filterStringBytes).trim();
+
+ commandIsValid = true;
}
@Override
public LttngAgentResponse execute(ILttngTcpClientListener agent) {
- boolean success = agent.eventEnabled(this.eventName);
+ if (!commandIsValid) {
+ return LttngAgentResponse.FAILURE_RESPONSE;
+ }
+
+ EventRule rule = new EventRule(eventName, logLevelFilter, filterString);
+ boolean success = agent.eventEnabled(rule);
return (success ? LttngAgentResponse.SUCESS_RESPONSE : LttngAgentResponse.FAILURE_RESPONSE);
}
}