text: /*
   * Copyright (C) 2012-2013, 2016 Apple Inc. All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   *
   * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
   * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
   * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
   * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
   * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
   * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
   * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
   * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
   * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
   */
  
  #include "config.h"
  #include "ProfilerDatabase.h"
  
  #include "CatchScope.h"
  #include "CodeBlock.h"
  #include "JSONObject.h"
  #include "ObjectConstructor.h"
  #include "JSCInlines.h"
  #include <wtf/CurrentTime.h>
  #include <wtf/FilePrintStream.h>
  
  namespace JSC { namespace Profiler {
  
  static std::atomic<int> databaseCounter;
  
  static StaticLock registrationLock;
  static std::atomic<int> didRegisterAtExit;
  static Database* firstDatabase;
  
  Database::Database(VM& vm)
      : m_databaseID(++databaseCounter)
      , m_vm(vm)
      , m_shouldSaveAtExit(false)
      , m_nextRegisteredDatabase(0)
  {
  }
  
  Database::~Database()
  {
      if (m_shouldSaveAtExit) {
          removeDatabaseFromAtExit();
          performAtExitSave();
      }
  }
  
  Bytecodes* Database::ensureBytecodesFor(CodeBlock* codeBlock)
  {
      LockHolder locker(m_lock);
      return ensureBytecodesFor(locker, codeBlock);
  }
  
  Bytecodes* Database::ensureBytecodesFor(const AbstractLocker&, CodeBlock* codeBlock)
  {
      codeBlock = codeBlock->baselineAlternative();
      
      HashMap<CodeBlock*, Bytecodes*>::iterator iter = m_bytecodesMap.find(codeBlock);
      if (iter != m_bytecodesMap.end())
          return iter->value;
      
      m_bytecodes.append(Bytecodes(m_bytecodes.size(), codeBlock));
      Bytecodes* result = &m_bytecodes.last();
      
      m_bytecodesMap.add(codeBlock, result);
      
      return result;
  }
  
  void Database::notifyDestruction(CodeBlock* codeBlock)
  {
      LockHolder locker(m_lock);
      
      m_bytecodesMap.remove(codeBlock);
      m_compilationMap.remove(codeBlock);
  }
  
  void Database::addCompilation(CodeBlock* codeBlock, Ref<Compilation>&& compilation)
  {
      LockHolder locker(m_lock);
      ASSERT(!isCompilationThread());
  
      m_compilations.append(compilation.copyRef());
      m_compilationMap.set(codeBlock, WTFMove(compilation));
  }
  
  JSValue Database::toJS(ExecState* exec) const
  {
      VM& vm = exec->vm();
      auto scope = DECLARE_THROW_SCOPE(vm);
      JSObject* result = constructEmptyObject(exec);
      
      JSArray* bytecodes = constructEmptyArray(exec, 0);
      RETURN_IF_EXCEPTION(scope, { });
      for (unsigned i = 0; i < m_bytecodes.size(); ++i) {
          auto value = m_bytecodes[i].toJS(exec);
          RETURN_IF_EXCEPTION(scope, { });
          bytecodes->putDirectIndex(exec, i, value);
          RETURN_IF_EXCEPTION(scope, { });
      }
      result->putDirect(vm, vm.propertyNames->bytecodes, bytecodes);
      
      JSArray* compilations = constructEmptyArray(exec, 0);
      RETURN_IF_EXCEPTION(scope, { });
      for (unsigned i = 0; i < m_compilations.size(); ++i) {
          auto value = m_compilations[i]->toJS(exec);
          RETURN_IF_EXCEPTION(scope, { });
          compilations->putDirectIndex(exec, i, value);
          RETURN_IF_EXCEPTION(scope, { });
      }
      result->putDirect(vm, vm.propertyNames->compilations, compilations);
      
      JSArray* events = constructEmptyArray(exec, 0);
      RETURN_IF_EXCEPTION(scope, { });
      for (unsigned i = 0; i < m_events.size(); ++i) {
          auto value = m_events[i].toJS(exec);
          RETURN_IF_EXCEPTION(scope, { });
          events->putDirectIndex(exec, i, value);
          RETURN_IF_EXCEPTION(scope, { });
      }
      result->putDirect(vm, vm.propertyNames->events, events);
      
      return result;
  }
  
  String Database::toJSON() const
  {
      auto scope = DECLARE_THROW_SCOPE(m_vm);
      JSGlobalObject* globalObject = JSGlobalObject::create(
          m_vm, JSGlobalObject::createStructure(m_vm, jsNull()));
  
      auto value = toJS(globalObject->globalExec());
      RETURN_IF_EXCEPTION(scope, String());
      scope.release();
      return JSONStringify(globalObject->globalExec(), value, 0);
  }
  
  bool Database::save(const char* filename) const
  {
      auto scope = DECLARE_CATCH_SCOPE(m_vm);
      auto out = FilePrintStream::open(filename, "w");
      if (!out)
          return false;
      
      String data = toJSON();
      if (UNLIKELY(scope.exception())) {
          scope.clearException();
          return false;
      }
      out->print(data);
      return true;
  }
  
  void Database::registerToSaveAtExit(const char* filename)
  {
      m_atExitSaveFilename = filename;
      
      if (m_shouldSaveAtExit)
          return;
      
      addDatabaseToAtExit();
      m_shouldSaveAtExit = true;
  }
  
  void Database::logEvent(CodeBlock* codeBlock, const char* summary, const CString& detail)
  {
      LockHolder locker(m_lock);
      
      Bytecodes* bytecodes = ensureBytecodesFor(locker, codeBlock);
      Compilation* compilation = m_compilationMap.get(codeBlock);
      m_events.append(Event(WallTime::now(), bytecodes, compilation, summary, detail));
  }
  
  void Database::addDatabaseToAtExit()
  {
      if (++didRegisterAtExit == 1)
          atexit(atExitCallback);
      
      LockHolder holder(registrationLock);
      m_nextRegisteredDatabase = firstDatabase;
      firstDatabase = this;
  }
  
  void Database::removeDatabaseFromAtExit()
  {
      LockHolder holder(registrationLock);
      for (Database** current = &firstDatabase; *current; current = &(*current)->m_nextRegisteredDatabase) {
          if (*current != this)
              continue;
          *current = m_nextRegisteredDatabase;
          m_nextRegisteredDatabase = 0;
          m_shouldSaveAtExit = false;
          break;
      }
  }
  
  void Database::performAtExitSave() const
  {
      JSLockHolder lock(m_vm);
      save(m_atExitSaveFilename.data());
  }
  
  Database* Database::removeFirstAtExitDatabase()
  {
      LockHolder holder(registrationLock);
      Database* result = firstDatabase;
      if (result) {
          firstDatabase = result->m_nextRegisteredDatabase;
          result->m_nextRegisteredDatabase = 0;
          result->m_shouldSaveAtExit = false;
      }
      return result;
  }
  
  void Database::atExitCallback()
  {
      while (Database* database = removeFirstAtExitDatabase())
          database->performAtExitSave();
  }
  
  } } // namespace JSC::Profiler
  
  