1 /*

     2  * Copyright (c) 2015, 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  */

    24 

    25 #include "precompiled.hpp"

    26 #include "jfr/dcmd/jfrDcmds.hpp"

    27 #include "jfr/jfrEvents.hpp"

    28 #include "jfr/periodic/jfrThreadDumpEvent.hpp"

    29 #include "logging/log.hpp"

    30 #include "utilities/exceptions.hpp"

    31 #include "utilities/ostream.hpp"

    32 

    33 /**

    34 *  Worker impl for generating and writing dcmd commands

    35 *  as jfr events.

    36 *  dispatch to diagnosticcommands "parse_and_execute"

    37 *

    38 *  param: cmd = the DCMD to execute (including options)

    39 */

    40 static bool execute_dcmd(bufferedStream& st, const char* const cmd) {

    41   Thread* THREAD = Thread::current();

    42   assert(!HAS_PENDING_EXCEPTION, "dcmd does not expect pending exceptions on entry!");

    43   // delegate to DCmd execution

    44   DCmd::parse_and_execute(DCmd_Source_Internal, &st, cmd, ' ', THREAD);

    45   if (HAS_PENDING_EXCEPTION) {

    46     log_debug(jfr, system)("unable to create jfr event for DCMD %s", cmd);

    47     log_debug(jfr, system)("exception type: %s", PENDING_EXCEPTION->klass()->external_name());

    48     // don't unwind this exception

    49     CLEAR_PENDING_EXCEPTION;

    50     // if exception occurred,

    51     // reset stream.

    52     st.reset();

    53     return false;

    54   }

    55   return true;

    56 }

    57 

    58 // caller needs ResourceMark

    59 const char* JfrDcmdEvent::thread_dump() {

    60   assert(EventThreadDump::is_enabled(), "invariant");

    61   bufferedStream st;

    62   execute_dcmd(st, "Thread.print");

    63   return st.as_string();

    64 }