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content / browser / tracing / tracing_ui.cc [blame]
// Copyright 2012 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "content/browser/tracing/tracing_ui.h"
#include <stddef.h>
#include <memory>
#include <optional>
#include <set>
#include <string>
#include <utility>
#include <vector>
#include "base/base64.h"
#include "base/command_line.h"
#include "base/format_macros.h"
#include "base/functional/bind.h"
#include "base/functional/callback_helpers.h"
#include "base/json/json_reader.h"
#include "base/json/json_writer.h"
#include "base/memory/ref_counted_memory.h"
#include "base/strings/string_number_conversions.h"
#include "base/strings/string_split.h"
#include "base/strings/string_util.h"
#include "base/trace_event/trace_event.h"
#include "base/values.h"
#include "content/browser/tracing/grit/tracing_resources.h"
#include "content/browser/tracing/tracing_controller_impl.h"
#include "content/public/browser/browser_context.h"
#include "content/public/browser/browser_thread.h"
#include "content/public/browser/content_browser_client.h"
#include "content/public/browser/storage_partition.h"
#include "content/public/browser/tracing_controller.h"
#include "content/public/browser/web_contents.h"
#include "content/public/browser/web_ui.h"
#include "content/public/browser/web_ui_data_source.h"
#include "content/public/common/content_client.h"
#include "content/public/common/url_constants.h"
#include "services/tracing/public/cpp/perfetto/perfetto_config.h"
#include "services/tracing/public/cpp/perfetto/perfetto_session.h"
#include "third_party/perfetto/include/perfetto/tracing/tracing.h"
#include "third_party/perfetto/protos/perfetto/common/trace_stats.gen.h"
namespace content {
namespace {
constexpr char kStreamFormat[] = "stream_format";
constexpr char kStreamFormatProtobuf[] = "protobuf";
constexpr char kStreamFormatJSON[] = "json";
perfetto::TracingSession* g_tracing_session = nullptr;
void OnGotCategories(WebUIDataSource::GotDataCallback callback,
const std::set<std::string>& category_set) {
base::Value::List category_list;
for (const std::string& category : category_set) {
category_list.Append(category);
}
auto res = base::MakeRefCounted<base::RefCountedString>();
base::JSONWriter::Write(category_list, &res->as_string());
std::move(callback).Run(res);
}
void OnRecordingEnabledAck(WebUIDataSource::GotDataCallback callback);
bool BeginRecording(const std::string& data64,
WebUIDataSource::GotDataCallback callback) {
base::trace_event::TraceConfig trace_config("", "");
std::string stream_format;
if (!TracingUI::GetTracingOptions(data64, trace_config, stream_format))
return false;
// TODO(skyostil): Migrate all use cases from TracingController to Perfetto.
if (stream_format == kStreamFormatProtobuf) {
delete g_tracing_session;
g_tracing_session =
perfetto::Tracing::NewTrace(perfetto::BackendType::kCustomBackend)
.release();
g_tracing_session->Setup(tracing::GetDefaultPerfettoConfig(trace_config));
auto shared_callback = base::MakeRefCounted<
base::RefCountedData<WebUIDataSource::GotDataCallback>>(
std::move(callback));
g_tracing_session->SetOnStartCallback([shared_callback] {
OnRecordingEnabledAck(std::move(shared_callback->data));
});
g_tracing_session->Start();
return true;
}
return TracingController::GetInstance()->StartTracing(
trace_config,
base::BindOnce(&OnRecordingEnabledAck, std::move(callback)));
}
void OnTraceBufferUsageResult(WebUIDataSource::GotDataCallback callback,
float percent_full,
size_t approximate_event_count) {
std::string str = base::NumberToString(percent_full);
std::move(callback).Run(
base::MakeRefCounted<base::RefCountedString>(std::move(str)));
}
bool GetTraceBufferUsage(WebUIDataSource::GotDataCallback callback) {
if (g_tracing_session) {
// |callback| is move-only, so in order to pass it through a copied lambda
// we need to temporarily move it on the heap.
auto shared_callback = base::MakeRefCounted<
base::RefCountedData<WebUIDataSource::GotDataCallback>>(
std::move(callback));
g_tracing_session->GetTraceStats(
[shared_callback](
perfetto::TracingSession::GetTraceStatsCallbackArgs args) {
std::string usage;
perfetto::protos::gen::TraceStats trace_stats;
if (args.success &&
trace_stats.ParseFromArray(args.trace_stats_data.data(),
args.trace_stats_data.size())) {
double percent_full = tracing::GetTraceBufferUsage(trace_stats);
usage = base::NumberToString(percent_full);
}
std::move(shared_callback->data)
.Run(base::MakeRefCounted<base::RefCountedString>(
std::move(usage)));
});
return true;
}
return TracingController::GetInstance()->GetTraceBufferUsage(
base::BindOnce(OnTraceBufferUsageResult, std::move(callback)));
}
void ReadProtobufTraceData(
scoped_refptr<TracingController::TraceDataEndpoint> endpoint,
perfetto::TracingSession::ReadTraceCallbackArgs args) {
if (args.size) {
auto data_string = std::make_unique<std::string>(args.data, args.size);
endpoint->ReceiveTraceChunk(std::move(data_string));
}
if (!args.has_more)
endpoint->ReceivedTraceFinalContents();
}
void TracingCallbackWrapperBase64(WebUIDataSource::GotDataCallback callback,
std::unique_ptr<std::string> data) {
base::RefCountedString* data_base64 = new base::RefCountedString();
data_base64->as_string() = base::Base64Encode(*data);
std::move(callback).Run(data_base64);
}
bool EndRecording(WebUIDataSource::GotDataCallback callback) {
if (!TracingController::GetInstance()->IsTracing() && !g_tracing_session)
return false;
scoped_refptr<TracingController::TraceDataEndpoint> data_endpoint =
TracingControllerImpl::CreateCompressedStringEndpoint(
TracingControllerImpl::CreateCallbackEndpoint(base::BindOnce(
TracingCallbackWrapperBase64, std::move(callback))),
false /* compress_with_background_priority */);
if (g_tracing_session) {
perfetto::TracingSession* session = g_tracing_session;
g_tracing_session = nullptr;
session->SetOnStopCallback([session, data_endpoint] {
session->ReadTrace(
[session, data_endpoint](
perfetto::TracingSession::ReadTraceCallbackArgs args) {
ReadProtobufTraceData(data_endpoint, args);
if (!args.has_more)
delete session;
});
});
session->Stop();
return true;
}
return TracingController::GetInstance()->StopTracing(data_endpoint);
}
void OnRecordingEnabledAck(WebUIDataSource::GotDataCallback callback) {
std::move(callback).Run(base::MakeRefCounted<base::RefCountedString>());
}
bool OnBeginJSONRequest(const std::string& path,
WebUIDataSource::GotDataCallback callback) {
if (path == "json/categories") {
return TracingController::GetInstance()->GetCategories(
base::BindOnce(OnGotCategories, std::move(callback)));
}
const char kBeginRecordingPath[] = "json/begin_recording?";
if (base::StartsWith(path, kBeginRecordingPath,
base::CompareCase::SENSITIVE)) {
std::string data = path.substr(strlen(kBeginRecordingPath));
return BeginRecording(data, std::move(callback));
}
if (path == "json/get_buffer_percent_full") {
return GetTraceBufferUsage(std::move(callback));
}
if (path == "json/end_recording_compressed") {
return EndRecording(std::move(callback));
}
LOG(ERROR) << "Unhandled request to " << path;
return false;
}
bool OnShouldHandleRequest(const std::string& path) {
return base::StartsWith(path, "json/", base::CompareCase::SENSITIVE);
}
void OnTracingRequest(const std::string& path,
WebUIDataSource::GotDataCallback callback) {
DCHECK(OnShouldHandleRequest(path));
// OnBeginJSONRequest() only runs |callback| if it returns true. But it needs
// to take ownership of |callback| even though it won't call |callback|
// sometimes, as it binds |callback| into other callbacks before it makes that
// decision. So we must give it one copy and keep one ourselves.
auto split_callback = base::SplitOnceCallback(std::move(callback));
if (!OnBeginJSONRequest(path, std::move(split_callback.first))) {
std::string error("##ERROR##");
std::move(split_callback.second)
.Run(base::MakeRefCounted<base::RefCountedString>(std::move(error)));
}
}
} // namespace
////////////////////////////////////////////////////////////////////////////////
//
// TracingUI
//
////////////////////////////////////////////////////////////////////////////////
TracingUI::TracingUI(WebUI* web_ui) : WebUIController(web_ui) {
// Set up the chrome://tracing/ source.
WebUIDataSource* source = WebUIDataSource::CreateAndAdd(
web_ui->GetWebContents()->GetBrowserContext(), kChromeUITracingHost);
source->DisableTrustedTypesCSP();
source->UseStringsJs();
source->SetDefaultResource(IDR_TRACING_ABOUT_TRACING_HTML);
source->AddResourcePath("tracing.js", IDR_TRACING_ABOUT_TRACING_JS);
source->SetRequestFilter(base::BindRepeating(OnShouldHandleRequest),
base::BindRepeating(OnTracingRequest));
}
TracingUI::~TracingUI() = default;
// static
bool TracingUI::GetTracingOptions(const std::string& data64,
base::trace_event::TraceConfig& trace_config,
std::string& out_stream_format) {
std::string data;
if (!base::Base64Decode(data64, &data)) {
LOG(ERROR) << "Options were not base64 encoded.";
return false;
}
std::optional<base::Value> options = base::JSONReader::Read(data);
if (!options) {
LOG(ERROR) << "Options were not valid JSON";
return false;
}
base::Value::Dict* options_dict = options->GetIfDict();
if (!options_dict) {
LOG(ERROR) << "Options must be dict";
return false;
}
if (const std::string* stream_format =
options_dict->FindString(kStreamFormat)) {
out_stream_format = *stream_format;
} else {
out_stream_format = kStreamFormatJSON;
}
// New-style options dictionary.
trace_config = base::trace_event::TraceConfig(*options_dict);
return true;
}
} // namespace content