Update from https://crrev.com/333737

base/trace_event/trace_config.h

Index: base/trace_event/trace_config.h
diff --git a/base/trace_event/trace_config.h b/base/trace_event/trace_config.h
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+// Copyright (c) 2015 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.
+
+#ifndef BASE_TRACE_EVENT_TRACE_CONFIG_H_
+#define BASE_TRACE_EVENT_TRACE_CONFIG_H_
+
+#include <string>
+#include <vector>
+
+#include "base/base_export.h"
+#include "base/gtest_prod_util.h"
+#include "base/values.h"
+
+namespace base {
+namespace trace_event {
+
+// Options determines how the trace buffer stores data.
+enum TraceRecordMode {
+  // Record until the trace buffer is full.
+  RECORD_UNTIL_FULL,
+
+  // Record until the user ends the trace. The trace buffer is a fixed size
+  // and we use it as a ring buffer during recording.
+  RECORD_CONTINUOUSLY,
+
+  // Record until the trace buffer is full, but with a huge buffer size.
+  RECORD_AS_MUCH_AS_POSSIBLE,
+
+  // Echo to console. Events are discarded.
+  ECHO_TO_CONSOLE,
+};
+
+class BASE_EXPORT TraceConfig {
+ public:
+  typedef std::vector<std::string> StringList;
+
+  TraceConfig();
+
+  // Create TraceConfig object from category filter and trace options strings.
+  //
+  // |category_filter_string| is a comma-delimited list of category wildcards.
+  // A category can have an optional '-' prefix to make it an excluded category.
+  // All the same rules apply above, so for example, having both included and
+  // excluded categories in the same list would not be supported.
+  //
+  // Category filters can also be used to configure synthetic delays.
+  //
+  // |trace_options_string| is a comma-delimited list of trace options.
+  // Possible options are: "record-until-full", "record-continuously",
+  // "record-as-much-as-possible", "trace-to-console", "enable-sampling",
+  // "enable-systrace" and "enable-argument-filter".
+  // The first 4 options are trace recoding modes and hence
+  // mutually exclusive. If more than one trace recording modes appear in the
+  // options_string, the last one takes precedence. If none of the trace
+  // recording mode is specified, recording mode is RECORD_UNTIL_FULL.
+  //
+  // The trace option will first be reset to the default option
+  // (record_mode set to RECORD_UNTIL_FULL, enable_sampling, enable_systrace,
+  // and enable_argument_filter set to false) before options parsed from
+  // |trace_options_string| are applied on it. If |trace_options_string| is
+  // invalid, the final state of trace options is undefined.
+  //
+  // Example: TraceConfig("test_MyTest*", "record-until-full");
+  // Example: TraceConfig("test_MyTest*,test_OtherStuff",
+  //                      "record-continuously, enable-sampling");
+  // Example: TraceConfig("-excluded_category1,-excluded_category2",
+  //                      "record-until-full, trace-to-console");
+  //          would set ECHO_TO_CONSOLE as the recording mode.
+  // Example: TraceConfig("-*,webkit", "");
+  //          would disable everything but webkit; and use default options.
+  // Example: TraceConfig("-webkit", "");
+  //          would enable everything but webkit; and use default options.
+  // Example: TraceConfig("DELAY(gpu.PresentingFrame;16)", "");
+  //          would make swap buffers always take at least 16 ms; and use
+  //          default options.
+  // Example: TraceConfig("DELAY(gpu.PresentingFrame;16;oneshot)", "");
+  //          would make swap buffers take at least 16 ms the first time it is
+  //          called; and use default options.
+  // Example: TraceConfig("DELAY(gpu.PresentingFrame;16;alternating)", "");
+  //          would make swap buffers take at least 16 ms every other time it
+  //          is called; and use default options.
+  TraceConfig(const std::string& category_filter_string,
+              const std::string& trace_options_string);
+
+  TraceConfig(const std::string& category_filter_string,
+              TraceRecordMode record_mode);
+
+  // Create TraceConfig object from the trace config string.
+  //
+  // |config_string| is a dictionary formatted as a JSON string, containing both
+  // category filters and trace options.
+  //
+  // Example:
+  //   {
+  //     "record_mode": "record-continuously",
+  //     "enable_sampling": true,
+  //     "enable_systrace": true,
+  //     "enable_argument_filter": true,
+  //     "included_categories": ["included",
+  //                             "inc_pattern*",
+  //                             "disabled-by-default-category1"],
+  //     "excluded_categories": ["excluded", "exc_pattern*"],
+  //     "synthetic_delays": ["test.Delay1;16", "test.Delay2;32"]
+  //   }
+  explicit TraceConfig(const std::string& config_string);
+
+  TraceConfig(const TraceConfig& tc);
+
+  ~TraceConfig();
+
+  TraceConfig& operator=(const TraceConfig& rhs);
+
+  // Return a list of the synthetic delays specified in this category filter.
+  const StringList& GetSyntheticDelayValues() const;
+
+  TraceRecordMode GetTraceRecordMode() const { return record_mode_; }
+  bool IsSamplingEnabled() const { return enable_sampling_; }
+  bool IsSystraceEnabled() const { return enable_systrace_; }
+  bool IsArgumentFilterEnabled() const { return enable_argument_filter_; }
+
+  void SetTraceRecordMode(TraceRecordMode mode) { record_mode_ = mode; }
+  void EnableSampling() { enable_sampling_ = true; }
+  void EnableSystrace() { enable_systrace_ = true; }
+  void EnableArgumentFilter() { enable_argument_filter_ = true; }
+
+  // Writes the string representation of the TraceConfig. The string is JSON
+  // formatted.
+  std::string ToString() const;
+
+  // Write the string representation of the CategoryFilter part.
+  std::string ToCategoryFilterString() const;
+
+  // Returns true if at least one category in the list is enabled by this
+  // trace config.
+  bool IsCategoryGroupEnabled(const char* category_group) const;
+
+  // Merges config with the current TraceConfig
+  void Merge(const TraceConfig& config);
+
+  void Clear();
+
+ private:
+  FRIEND_TEST_ALL_PREFIXES(TraceConfigTest, TraceConfigFromValidLegacyFormat);
+  FRIEND_TEST_ALL_PREFIXES(TraceConfigTest,
+                           TraceConfigFromInvalidLegacyStrings);
+  FRIEND_TEST_ALL_PREFIXES(TraceConfigTest, ConstructDefaultTraceConfig);
+  FRIEND_TEST_ALL_PREFIXES(TraceConfigTest, TraceConfigFromValidString);
+  FRIEND_TEST_ALL_PREFIXES(TraceConfigTest, TraceConfigFromInvalidString);
+  FRIEND_TEST_ALL_PREFIXES(TraceConfigTest,
+                           IsEmptyOrContainsLeadingOrTrailingWhitespace);
+
+  // The default trace config, used when none is provided.
+  // Allows all non-disabled-by-default categories through, except if they end
+  // in the suffix 'Debug' or 'Test'.
+  void InitializeDefault();
+
+  // Initialize from the config string
+  void InitializeFromConfigString(const std::string& config_string);
+
+  // Initialize from category filter and trace options strings
+  void InitializeFromStrings(const std::string& category_filter_string,
+                             const std::string& trace_options_string);
+
+  void SetCategoriesFromIncludedList(const base::ListValue& included_list);
+  void SetCategoriesFromExcludedList(const base::ListValue& excluded_list);
+  void SetSyntheticDelaysFromList(const base::ListValue& list);
+  void AddCategoryToDict(base::DictionaryValue& dict,
+                         const char* param,
+                         const StringList& categories) const;
+
+  // Convert TraceConfig to the dict representation of the TraceConfig.
+  void ToDict(base::DictionaryValue& dict) const;
+
+  std::string ToTraceOptionsString() const;
+
+  void WriteCategoryFilterString(const StringList& values,
+                                 std::string* out,
+                                 bool included) const;
+  void WriteCategoryFilterString(const StringList& delays,
+                                 std::string* out) const;
+
+  // Returns true if category is enable according to this trace config.
+  bool IsCategoryEnabled(const char* category_name) const;
+
+  static bool IsEmptyOrContainsLeadingOrTrailingWhitespace(
+      const std::string& str);
+
+  bool HasIncludedPatterns() const;
+
+  TraceRecordMode record_mode_;
+  bool enable_sampling_ : 1;
+  bool enable_systrace_ : 1;
+  bool enable_argument_filter_ : 1;
+
+  StringList included_categories_;
+  StringList disabled_categories_;
+  StringList excluded_categories_;
+  StringList synthetic_delays_;
+};
+
+}  // namespace trace_event
+}  // namespace base
+
+#endif  // BASE_TRACE_EVENT_TRACE_CONFIG_H_