ppb_trace_event_impl.cc

// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "ppapi/shared_impl/ppb_trace_event_impl.h"

#include "base/threading/platform_thread.h"
#include "base/trace_event/trace_event.h"
#include "ppapi/thunk/thunk.h"

namespace ppapi {

// PPB_Trace_Event_Dev is a shared implementation because Trace Events can be
// sent from either the plugin process or renderer process depending on whether
// the plugin is in- or out-of-process.  Also, for NaCl plugins these functions
// will be executed from untrusted code and handled appropriately by tracing
// functionality in the IRT.

// static
void* TraceEventImpl::GetCategoryEnabled(const char* category_name) {
  // This casting is here because all mem_t return types in Pepper are void* and
  // non-const.  All mem_t parameters are const void* so there is no way to
  // return a pointer type to the caller without some const_cast.  The pointer
  // type the tracing system works with is normally unsigned char*.
  return const_cast<void*>(static_cast<const void*>(
      base::trace_event::TraceLog::GetInstance()->GetCategoryGroupEnabled(
          category_name)));
}

// static
void TraceEventImpl::AddTraceEvent(int8_t phase,
                                   const void* category_enabled,
                                   const char* name,
                                   uint64_t id,
                                   uint32_t num_args,
                                   const char* arg_names[],
                                   const uint8_t arg_types[],
                                   const uint64_t arg_values[],
                                   uint8_t flags) {

  static_assert(sizeof(unsigned long long) == sizeof(uint64_t),
                "unexpected data type sizes");
  // NOTE: The |arg_values| cast is required to avoid a compiler warning,
  // since uint64_t and unsigned long long are not the same type, even
  // though they have the same size, on all platforms we care about.
  base::trace_event::TraceArguments args(
      num_args, arg_names, arg_types,
      reinterpret_cast<const unsigned long long*>(arg_values));
  base::trace_event::TraceLog::GetInstance()->AddTraceEvent(
      phase, static_cast<const unsigned char*>(category_enabled), name,
      trace_event_internal::kGlobalScope, id, &args, flags);
}

// static
void TraceEventImpl::AddTraceEventWithThreadIdAndTimestamp(
    int8_t phase,
    const void* category_enabled,
    const char* name,
    uint64_t id,
    int32_t thread_id,
    int64_t timestamp,
    uint32_t num_args,
    const char* arg_names[],
    const uint8_t arg_types[],
    const uint64_t arg_values[],
    uint8_t flags) {
  // See above comment about the cast to |const unsigned long long*|.
  base::trace_event::TraceArguments args(
      num_args, arg_names, arg_types,
      reinterpret_cast<const unsigned long long*>(arg_values));
  base::trace_event::TraceLog::GetInstance()
      ->AddTraceEventWithThreadIdAndTimestamp(
          phase, static_cast<const unsigned char*>(category_enabled), name,
          trace_event_internal::kGlobalScope, id, trace_event_internal::kNoId,
          thread_id, base::TimeTicks::FromInternalValue(timestamp), &args,
          flags);
}

// static
int64_t TraceEventImpl::Now() {
  return base::TimeTicks::Now().ToInternalValue();
}

// static
void TraceEventImpl::SetThreadName(const char* thread_name) {
  base::PlatformThread::SetName(thread_name);
}

namespace {

const PPB_Trace_Event_Dev_0_1 g_ppb_trace_event_thunk_0_1 = {
    &TraceEventImpl::GetCategoryEnabled, &TraceEventImpl::AddTraceEvent,
    &TraceEventImpl::SetThreadName, };

const PPB_Trace_Event_Dev_0_2 g_ppb_trace_event_thunk_0_2 = {
    &TraceEventImpl::GetCategoryEnabled,
    &TraceEventImpl::AddTraceEvent,
    &TraceEventImpl::AddTraceEventWithThreadIdAndTimestamp,
    &TraceEventImpl::Now,
    &TraceEventImpl::SetThreadName, };

}  // namespace ppapi

}  // namespace

namespace ppapi {
namespace thunk {

const PPB_Trace_Event_Dev_0_1* GetPPB_Trace_Event_Dev_0_1_Thunk() {
  return &g_ppb_trace_event_thunk_0_1;
}

const PPB_Trace_Event_Dev_0_2* GetPPB_Trace_Event_Dev_0_2_Thunk() {
  return &g_ppb_trace_event_thunk_0_2;
}

}  // namespace thunk
}  // namespace ppapi