CSE2410 Fall 2014 Bounce

// Copyright Joyent, Inc. and other Node contributors.

//

// Permission is hereby granted, free of charge, to any person obtaining a

// copy of this software and associated documentation files (the

// "Software"), to deal in the Software without restriction, including

// without limitation the rights to use, copy, modify, merge, publish,

// distribute, sublicense, and/or sell copies of the Software, and to permit

// persons to whom the Software is furnished to do so, subject to the

// following conditions:

//

// The above copyright notice and this permission notice shall be included

// in all copies or substantial portions of the Software.

//

// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS

// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF

// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN

// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,

// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR

// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE

// USE OR OTHER DEALINGS IN THE SOFTWARE.

#include "node_dtrace.h"

#include "node_win32_etw_provider.h"

#include "node_etw_provider.h"

namespace node {

using namespace v8;

HMODULE advapi;

REGHANDLE node_provider;

EventRegisterFunc event_register;

EventUnregisterFunc event_unregister;

EventWriteFunc event_write;

int events_enabled;

// This callback is called by ETW when consumers of our provider

// are enabled or disabled.

// The callback is dispatched on ETW thread.

void NTAPI etw_events_enable_callback(

  LPCGUID SourceId,

  ULONG IsEnabled,

  UCHAR Level,

  ULONGLONG MatchAnyKeyword,

  ULONGLONG MatchAllKeywords,

  PEVENT_FILTER_DESCRIPTOR FilterData,

  PVOID CallbackContext) {

  if (IsEnabled) {

    events_enabled++;

  } else {

    events_enabled--;

  }

}

void init_etw() {

  events_enabled = 0;

  advapi = LoadLibrary("advapi32.dll");

  if (advapi) {

    event_register = (EventRegisterFunc)

      GetProcAddress(advapi, "EventRegister");

    event_unregister = (EventUnregisterFunc)

      GetProcAddress(advapi, "EventUnregister");

    event_write = (EventWriteFunc)GetProcAddress(advapi, "EventWrite");

    if (event_register) {    

      DWORD status = event_register(&NODE_ETW_PROVIDER,

                                    etw_events_enable_callback,

                                    NULL,

                                    &node_provider);

      assert(status == ERROR_SUCCESS);

    }

  }

}

void shutdown_etw() {

  if (advapi && event_unregister && node_provider) {

    event_unregister(node_provider);

    node_provider = 0;

  }

  events_enabled = 0;

  if (advapi) {

    FreeLibrary(advapi);

    advapi = NULL;

  }

}

}