1 /*
   2  * Copyright (c) 1997, 2003, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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   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.
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   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
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  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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  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
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  24 
  25 // Events and EventMark provide interfaces to log events taking place in the vm.
  26 // This facility is extremly useful for post-mortem debugging. The eventlog
  27 // often provides crucial information about events leading up to the crash.
  28 //
  29 // All arguments past the format string must be passed as an intptr_t.
  30 //
  31 // To log a single event use:
  32 //    Events::log("New nmethod has been created " INTPTR_FORMAT, nm);
  33 //
  34 // To log a block of events use:
  35 //    EventMark m("GarbageCollecting %d", (intptr_t)gc_number);
  36 //
  37 // The constructor to eventlog indents the eventlog until the
  38 // destructor has been executed.
  39 //
  40 // IMPLEMENTATION RESTRICTION:
  41 //   Max 3 arguments are saved for each logged event.
  42 //
  43 
  44 class Events : AllStatic {
  45  public:
  46   // Logs an event, format as printf
  47   static void log(const char* format, ...) PRODUCT_RETURN;
  48 
  49   // Prints all events in the buffer
  50   static void print_all(outputStream* st) PRODUCT_RETURN;
  51 
  52   // Prints last number events from the event buffer
  53   static void print_last(outputStream *st, int number) PRODUCT_RETURN;
  54 };
  55 
  56 class EventMark : public StackObj {
  57  public:
  58   // log a begin event, format as printf
  59   EventMark(const char* format, ...) PRODUCT_RETURN;
  60   // log an end event
  61   ~EventMark() PRODUCT_RETURN;
  62 };
  63 
  64 int print_all_events(outputStream *st);