Making structure for ContentSettings and its corresponding strings.

components/content_settings/core/browser/content_settings_utils.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 "components/content_settings/core/browser/content_settings_utils.h"
 
 #include <vector>
 
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/prefs/pref_registry.h"
 #include "base/strings/string_split.h"
 #include "base/values.h"
 #include "components/content_settings/core/browser/content_settings_provider.h"
 #include "components/content_settings/core/browser/content_settings_rule.h"
 #include "components/content_settings/core/browser/host_content_settings_map.h"
 #include "components/content_settings/core/browser/website_settings_info.h"
 #include "components/content_settings/core/browser/website_settings_registry.h"
 #include "components/content_settings/core/common/content_settings_pattern.h"
 #include "components/pref_registry/pref_registry_syncable.h"
 #include "url/gurl.h"
 
 namespace {
 
 const char kPatternSeparator[] = ",";
 
+struct ContentSettingsStringMapping {
+  ContentSetting content_setting;
+  const char* content_setting_str;
+};
+const ContentSettingsStringMapping kContentSettingsStringMapping[] = {
+    {CONTENT_SETTING_DEFAULT, "default"},
+    {CONTENT_SETTING_ALLOW, "allow"},
+    {CONTENT_SETTING_BLOCK, "block"},
+    {CONTENT_SETTING_ASK, "ask"},
+    {CONTENT_SETTING_SESSION_ONLY, "session"},
+    {CONTENT_SETTING_DETECT_IMPORTANT_CONTENT, "detect"},
+};
+static_assert(arraysize(kContentSettingsStringMapping) ==
+                  CONTENT_SETTING_NUM_SETTINGS,
+              "kContentSettingsToFromString should have "
+              "CONTENT_SETTING_NUM_SETTINGS elements");
 }  // namespace
 
 namespace content_settings {
 
 std::string ContentSettingToString(ContentSetting setting) {
-  switch (setting) {
-    case CONTENT_SETTING_ALLOW:
-      return "allow";
-    case CONTENT_SETTING_ASK:
-      return "ask";
-    case CONTENT_SETTING_BLOCK:
-      return "block";
-    case CONTENT_SETTING_SESSION_ONLY:
-      return "session";
-    case CONTENT_SETTING_DETECT_IMPORTANT_CONTENT:
-      return "detect";
-    case CONTENT_SETTING_DEFAULT:
-      return "default";
-    case CONTENT_SETTING_NUM_SETTINGS:
-      NOTREACHED();
-  }
-
-  return ResourceIdentifier();
+  DCHECK_GE(setting, CONTENT_SETTING_DEFAULT);
+  DCHECK_LT(setting, CONTENT_SETTING_NUM_SETTINGS);
+  DCHECK_EQ(kContentSettingsStringMapping[setting].content_setting, setting);
+  return kContentSettingsStringMapping[setting].content_setting_str;
 }
 
 ContentSetting ContentSettingFromString(const std::string& name) {
-  if (name == "allow")
-    return CONTENT_SETTING_ALLOW;
-  if (name == "ask")
-    return CONTENT_SETTING_ASK;
-  if (name == "block")
-    return CONTENT_SETTING_BLOCK;
-  if (name == "session")
-    return CONTENT_SETTING_SESSION_ONLY;
-  if (name == "detect")
-    return CONTENT_SETTING_DETECT_IMPORTANT_CONTENT;
-
+  for (size_t i = 1; i < arraysize(kContentSettingsStringMapping); ++i) {

[Bernhard Bauer, 2015/10/05 08:15:09]

Please add a comment explaining why we start with 1 here.

[Deepak, 2015/10/05 09:51:30]

Done.

+    if (name == kContentSettingsStringMapping[i].content_setting_str)
+      return kContentSettingsStringMapping[i].content_setting;
+  }
   NOTREACHED() << name << " is not a recognized content setting.";
   return CONTENT_SETTING_DEFAULT;
 }
 
 std::string CreatePatternString(
     const ContentSettingsPattern& item_pattern,
     const ContentSettingsPattern& top_level_frame_pattern) {
   return item_pattern.ToString()
          + std::string(kPatternSeparator)
          + top_level_frame_pattern.ToString();
@@ skipping 114 matching lines @@
       CONTENT_SETTINGS_TYPE_IMAGES,
       ResourceIdentifier(),
       &(rules->image_rules));
   map->GetSettingsForOneType(
       CONTENT_SETTINGS_TYPE_JAVASCRIPT,
       ResourceIdentifier(),
       &(rules->script_rules));
 }
 
 }  // namespace content_settings