Add source column to chrome://policy showing the origins of policies.

components/policy/core/common/policy_map.h

 // Copyright 2013 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 COMPONENTS_POLICY_CORE_COMMON_POLICY_MAP_H_
 #define COMPONENTS_POLICY_CORE_COMMON_POLICY_MAP_H_
 
 #include <map>
 #include <set>
 #include <string>
 
 #include "base/memory/scoped_ptr.h"
 #include "base/values.h"
 #include "components/policy/core/common/external_data_fetcher.h"
 #include "components/policy/core/common/policy_types.h"
 #include "components/policy/policy_export.h"
 
 namespace policy {
 
 // A mapping of policy names to policy values for a given policy namespace.
 class POLICY_EXPORT PolicyMap {
  public:
   // Each policy maps to an Entry which keeps the policy value as well as other
   // relevant data about the policy.
   struct POLICY_EXPORT Entry {
     PolicyLevel level;
     PolicyScope scope;
+    PolicySource source;

[Thiemo Nagel, 2015/09/01 17:40:37]

Please annotate that this is for debugging/display only.

[fhorschig, 2015/09/04 06:53:54]

Done.

     base::Value* value;
     ExternalDataFetcher* external_data_fetcher;
 
     Entry();
 
     // Deletes all members owned by |this|.
     void DeleteOwnedMembers();
 
     // Returns a copy of |this|.
     scoped_ptr<Entry> DeepCopy() const;
@@ skipping 13 matching lines @@
 
   // Returns a weak reference to the entry currently stored for key |policy|,
   // or NULL if not found. Ownership is retained by the PolicyMap.
   const Entry* Get(const std::string& policy) const;
 
   // Returns a weak reference to the value currently stored for key |policy|,
   // or NULL if not found. Ownership is retained by the PolicyMap.
   // This is equivalent to Get(policy)->value, when it doesn't return NULL.
   const base::Value* GetValue(const std::string& policy) const;
 
+  // Sets the source of every Entry in the Map to the passed |source|.
+  void SetSources(PolicySource source);

[Thiemo Nagel, 2015/09/01 17:40:37]

SetSource would seem easier understandable to me.

[fhorschig, 2015/09/04 06:53:54]

Obviously misleading name. It sets the sources of all Entries, not the map, so
SetEntrySources is more appropriate.

+
+  // Calls |Set| with default source.
+  void Set(const std::string& policy,
+           PolicyLevel level,
+           PolicyScope scope,
+           base::Value* value,
+           ExternalDataFetcher* external_data_fetcher);
+
   // Takes ownership of |value| and |external_data_fetcher|. Overwrites any
   // existing information stored in the map for the key |policy|.
   void Set(const std::string& policy,

[Thiemo Nagel, 2015/09/01 17:40:37]

Function overloading is frowned upon, cf.
http://google-styleguide.googlecode.com/svn/trunk/cppguide.html#Function_Over....

The combination of the old Set() and the new SetSource() should be sufficient
for all uses, shouldn't it?

[fhorschig, 2015/09/04 06:53:54]

SetSources manipulates ALL entries. We don't want to do this every time we add a
policy. The function gets a new name.

            PolicyLevel level,
            PolicyScope scope,
            base::Value* value,
-           ExternalDataFetcher* external_data_fetcher);
+           ExternalDataFetcher* external_data_fetcher,
+           PolicySource source);
 
   // Erase the given |policy|, if it exists in this map.
   void Erase(const std::string& policy);
 
   // Swaps the internal representation of |this| with |other|.
   void Swap(PolicyMap* other);
 
   // |this| becomes a copy of |other|. Any existing policies are dropped.
   void CopyFrom(const PolicyMap& other);
 
   // Returns a copy of |this|.
   scoped_ptr<PolicyMap> DeepCopy() const;
 
   // Merges policies from |other| into |this|. Existing policies are only
   // overridden by those in |other| if they have a higher priority, as defined
   // by Entry::has_higher_priority_than(). If a policy is contained in both
   // maps with the same priority, the current value in |this| is preserved.
   void MergeFrom(const PolicyMap& other);
 
-  // Loads the values in |policies| into this PolicyMap. All policies loaded
-  // will have |level| and |scope| in their entries. Existing entries are
-  // replaced.
+  // Calls |LoadFrom| with default source.
   void LoadFrom(const base::DictionaryValue* policies,
                 PolicyLevel level,
                 PolicyScope scope);
+  // Loads the values in |policies| into this PolicyMap. All policies loaded

[Thiemo Nagel, 2015/09/01 17:40:37]

Again, please don't overload.

[fhorschig, 2015/09/04 06:53:54]

Done.

+  // will have |level| and |scope| in their entries and originate from |source|.
+  // Existing entries are replaced.
+  void LoadFrom(const base::DictionaryValue* policies,
+                PolicyLevel level,
+                PolicyScope scope,
+                PolicySource source);
 
   // Compares this value map against |other| and stores all key names that have
   // different values or reference different external data in |differing_keys|.
   // This includes keys that are present only in one of the maps.
   // |differing_keys| is not cleared before the keys are added.
   void GetDifferingKeys(const PolicyMap& other,
                         std::set<std::string>* differing_keys) const;
 
   // Removes all policies that don't have the specified |level|. This is a
   // temporary helper method, until mandatory and recommended levels are served
@@ skipping 15 matching lines @@
                              const PolicyMapType::value_type& b);
 
   PolicyMapType map_;
 
   DISALLOW_COPY_AND_ASSIGN(PolicyMap);
 };
 
 }  // namespace policy
 
 #endif  // COMPONENTS_POLICY_CORE_COMMON_POLICY_MAP_H_