1 /*
   2  * Copyright (c) 2003, 2010, 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 #ifndef SHARE_VM_PRIMS_JVMTIEVENTCONTROLLER_HPP
  26 #define SHARE_VM_PRIMS_JVMTIEVENTCONTROLLER_HPP
  27 
  28 #include "jvmtifiles/jvmti.h"
  29 #include "memory/allocation.hpp"
  30 #include "utilities/globalDefinitions.hpp"
  31 
  32 // forward declaration
  33 class JvmtiEventControllerPrivate;
  34 class JvmtiEventController;
  35 class JvmtiEnvThreadState;
  36 class JvmtiFramePop;
  37 class JvmtiEnvBase;
  38 
  39 
  40 // Extension event support
  41 //
  42 // jvmtiExtEvent is the extensions equivalent of jvmtiEvent
  43 // jvmtiExtCallbacks is the extensions equivalent of jvmtiEventCallbacks
  44 
  45 // Extension events start JVMTI_MIN_EVENT_TYPE_VAL-1 and work towards 0.
  46 typedef enum {
  47   EXT_EVENT_CLASS_UNLOAD = JVMTI_MIN_EVENT_TYPE_VAL-1,
  48   EXT_MIN_EVENT_TYPE_VAL = EXT_EVENT_CLASS_UNLOAD,
  49   EXT_MAX_EVENT_TYPE_VAL = EXT_EVENT_CLASS_UNLOAD
  50 } jvmtiExtEvent;
  51 
  52 typedef struct {
  53   jvmtiExtensionEvent ClassUnload;
  54 } jvmtiExtEventCallbacks;
  55 
  56 
  57 // The complete range of events is EXT_MIN_EVENT_TYPE_VAL to
  58 // JVMTI_MAX_EVENT_TYPE_VAL (inclusive and contiguous).
  59 const int TOTAL_MIN_EVENT_TYPE_VAL = EXT_MIN_EVENT_TYPE_VAL;
  60 const int TOTAL_MAX_EVENT_TYPE_VAL = JVMTI_MAX_EVENT_TYPE_VAL;
  61 
  62 
  63 ///////////////////////////////////////////////////////////////
  64 //
  65 // JvmtiEventEnabled
  66 //
  67 // Utility class
  68 //
  69 // A boolean array indexed by event_type, used as an internal
  70 // data structure to track what JVMTI event types are enabled.
  71 // Used for user set enabling and disabling (globally and on a
  72 // per thread basis), and for computed merges across environments,
  73 // threads and the VM as a whole.
  74 //
  75 // for inlines see jvmtiEventController_inline.hpp
  76 //
  77 
  78 class JvmtiEventEnabled VALUE_OBJ_CLASS_SPEC {
  79 private:
  80   friend class JvmtiEventControllerPrivate;
  81   jlong _enabled_bits;
  82 #ifndef PRODUCT
  83   enum {
  84     JEE_INIT_GUARD = 0xEAD0
  85   } _init_guard;
  86 #endif
  87   static jlong bit_for(jvmtiEvent event_type);
  88   jlong get_bits();
  89   void set_bits(jlong bits);
  90 public:
  91   JvmtiEventEnabled();
  92   void clear();
  93   bool is_enabled(jvmtiEvent event_type);
  94   void set_enabled(jvmtiEvent event_type, bool enabled);
  95 };
  96 
  97 
  98 ///////////////////////////////////////////////////////////////
  99 //
 100 // JvmtiEnvThreadEventEnable
 101 //
 102 // JvmtiEventController data specific to a particular environment and thread.
 103 //
 104 // for inlines see jvmtiEventController_inline.hpp
 105 //
 106 
 107 class JvmtiEnvThreadEventEnable VALUE_OBJ_CLASS_SPEC {
 108 private:
 109   friend class JvmtiEventControllerPrivate;
 110   JvmtiEventEnabled _event_user_enabled;
 111   JvmtiEventEnabled _event_enabled;
 112 
 113 public:
 114   JvmtiEnvThreadEventEnable();
 115   ~JvmtiEnvThreadEventEnable();
 116   bool is_enabled(jvmtiEvent event_type);
 117   void set_user_enabled(jvmtiEvent event_type, bool enabled);
 118 };
 119 
 120 
 121 ///////////////////////////////////////////////////////////////
 122 //
 123 // JvmtiThreadEventEnable
 124 //
 125 // JvmtiEventController data specific to a particular thread.
 126 //
 127 // for inlines see jvmtiEventController_inline.hpp
 128 //
 129 
 130 class JvmtiThreadEventEnable VALUE_OBJ_CLASS_SPEC {
 131 private:
 132   friend class JvmtiEventControllerPrivate;
 133   JvmtiEventEnabled _event_enabled;
 134 
 135 public:
 136   JvmtiThreadEventEnable();
 137   ~JvmtiThreadEventEnable();
 138   bool is_enabled(jvmtiEvent event_type);
 139 };
 140 
 141 
 142 ///////////////////////////////////////////////////////////////
 143 //
 144 // JvmtiEnvEventEnable
 145 //
 146 // JvmtiEventController data specific to a particular environment.
 147 //
 148 // for inlines see jvmtiEventController_inline.hpp
 149 //
 150 
 151 class JvmtiEnvEventEnable VALUE_OBJ_CLASS_SPEC {
 152 private:
 153   friend class JvmtiEventControllerPrivate;
 154 
 155   // user set global event enablement indexed by jvmtiEvent
 156   JvmtiEventEnabled _event_user_enabled;
 157 
 158   // this flag indicates the presence (true) or absence (false) of event callbacks
 159   // it is indexed by jvmtiEvent
 160   JvmtiEventEnabled _event_callback_enabled;
 161 
 162   // indexed by jvmtiEvent true if enabled globally or on any thread.
 163   // True only if there is a callback for it.
 164   JvmtiEventEnabled _event_enabled;
 165 
 166 public:
 167   JvmtiEnvEventEnable();
 168   ~JvmtiEnvEventEnable();
 169   bool is_enabled(jvmtiEvent event_type);
 170   void set_user_enabled(jvmtiEvent event_type, bool enabled);
 171 };
 172 
 173 
 174 ///////////////////////////////////////////////////////////////
 175 //
 176 // JvmtiEventController
 177 //
 178 // The class is the access point for all actions that change
 179 // which events are active, this include:
 180 //      enabling and disabling events
 181 //      changing the callbacks/eventhook (they may be null)
 182 //      setting and clearing field watchpoints
 183 //      setting frame pops
 184 //      encountering frame pops
 185 //
 186 // for inlines see jvmtiEventController_inline.hpp
 187 //
 188 
 189 class JvmtiEventController : AllStatic {
 190 private:
 191   friend class JvmtiEventControllerPrivate;
 192 
 193   // for all environments, global array indexed by jvmtiEvent
 194   static JvmtiEventEnabled _universal_global_event_enabled;
 195 
 196 public:
 197   static bool is_enabled(jvmtiEvent event_type);
 198 
 199   // events that can ONLY be enabled/disabled globally (can't toggle on individual threads).
 200   static bool is_global_event(jvmtiEvent event_type);
 201 
 202   // is the event_type valid?
 203   // to do: check against valid event array
 204   static bool is_valid_event_type(jvmtiEvent event_type) {
 205     return ((int)event_type >= TOTAL_MIN_EVENT_TYPE_VAL)
 206         && ((int)event_type <= TOTAL_MAX_EVENT_TYPE_VAL);
 207   }
 208 
 209   // Use (thread == NULL) to enable/disable an event globally.
 210   // Use (thread != NULL) to enable/disable an event for a particular thread.
 211   // thread is ignored for events that can only be specified globally
 212   static void set_user_enabled(JvmtiEnvBase *env, JavaThread *thread,
 213                                jvmtiEvent event_type, bool enabled);
 214 
 215   // Setting callbacks changes computed enablement and must be done
 216   // at a safepoint otherwise a NULL callback could be attempted
 217   static void set_event_callbacks(JvmtiEnvBase *env,
 218                                   const jvmtiEventCallbacks* callbacks,
 219                                   jint size_of_callbacks);
 220 
 221   // Sets the callback function for a single extension event and enables
 222   // (or disables it).
 223   static void set_extension_event_callback(JvmtiEnvBase* env,
 224                                            jint extension_event_index,
 225                                            jvmtiExtensionEvent callback);
 226 
 227   static void set_frame_pop(JvmtiEnvThreadState *env_thread, JvmtiFramePop fpop);
 228   static void clear_frame_pop(JvmtiEnvThreadState *env_thread, JvmtiFramePop fpop);
 229   static void clear_to_frame_pop(JvmtiEnvThreadState *env_thread, JvmtiFramePop fpop);
 230 
 231   static void change_field_watch(jvmtiEvent event_type, bool added);
 232 
 233   static void thread_started(JavaThread *thread);
 234   static void thread_ended(JavaThread *thread);
 235 
 236   static void env_initialize(JvmtiEnvBase *env);
 237   static void env_dispose(JvmtiEnvBase *env);
 238 
 239   static void vm_start();
 240   static void vm_init();
 241   static void vm_death();
 242 };
 243 
 244 #endif // SHARE_VM_PRIMS_JVMTIEVENTCONTROLLER_HPP