components/policy/core/common/policy_bundle.cc

   1 // Copyright 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "components/policy/core/common/policy_bundle.h"
   6
   7 #include "base/logging.h"
   8 #include "base/stl_util.h"
   9
  10 namespace policy {
  11
  12 PolicyBundle::PolicyBundle() {}
  13
  14 PolicyBundle::~PolicyBundle() {
  15   Clear();
  16 }
  17
  18 PolicyMap& PolicyBundle::Get(const PolicyNamespace& ns) {
  19   DCHECK(ns.domain != POLICY_DOMAIN_CHROME || ns.component_id.empty());
  20   PolicyMap*& policy = policy_bundle_[ns];
  21   if (!policy)
  22     policy = new PolicyMap();
  23   return *policy;
  24 }
  25
  26 const PolicyMap& PolicyBundle::Get(const PolicyNamespace& ns) const {
  27   DCHECK(ns.domain != POLICY_DOMAIN_CHROME || ns.component_id.empty());
  28   const_iterator it = policy_bundle_.find(ns);
  29   return it == end() ? kEmpty_ : *it->second;
  30 }
  31
  32 void PolicyBundle::Swap(PolicyBundle* other) {
  33   policy_bundle_.swap(other->policy_bundle_);
  34 }
  35
  36 void PolicyBundle::CopyFrom(const PolicyBundle& other) {
  37   Clear();
  38   for (PolicyBundle::const_iterator it = other.begin();
  39        it != other.end(); ++it) {
  40     policy_bundle_[it->first] = it->second->DeepCopy().release();
  41   }
  42 }
  43
  44 void PolicyBundle::MergeFrom(const PolicyBundle& other) {
  45   // Iterate over both |this| and |other| in order; skip what's extra in |this|,
  46   // add what's missing, and merge the namespaces in common.
  47   MapType::iterator it_this = policy_bundle_.begin();
  48   MapType::iterator end_this = policy_bundle_.end();
  49   const_iterator it_other = other.begin();
  50   const_iterator end_other = other.end();
  51
  52   while (it_this != end_this && it_other != end_other) {
  53     if (it_this->first == it_other->first) {
  54       // Same namespace: merge existing PolicyMaps.
  55       it_this->second->MergeFrom(*it_other->second);
  56       ++it_this;
  57       ++it_other;
  58     } else if (it_this->first < it_other->first) {
  59       // |this| has a PolicyMap that |other| doesn't; skip it.
  60       ++it_this;
  61     } else if (it_other->first < it_this->first) {
  62       // |other| has a PolicyMap that |this| doesn't; copy it.
  63       PolicyMap*& policy = policy_bundle_[it_other->first];
  64       DCHECK(!policy);
  65       policy = it_other->second->DeepCopy().release();
  66       ++it_other;
  67     } else {
  68       NOTREACHED();
  69     }
  70   }
  71
  72   // Add extra PolicyMaps at the end.
  73   while (it_other != end_other) {
  74     PolicyMap*& policy = policy_bundle_[it_other->first];
  75     DCHECK(!policy);
  76     policy = it_other->second->DeepCopy().release();
  77     ++it_other;
  78   }
  79 }
  80
  81 bool PolicyBundle::Equals(const PolicyBundle& other) const {
  82   // Equals() has the peculiarity that an entry with an empty PolicyMap equals
  83   // an non-existant entry. This handles usage of non-const Get() that doesn't
  84   // insert any policies.
  85   const_iterator it_this = begin();
  86   const_iterator it_other = other.begin();
  87
  88   while (true) {
  89     // Skip empty PolicyMaps.
  90     while (it_this != end() && it_this->second->empty())
  91       ++it_this;
  92     while (it_other != other.end() && it_other->second->empty())
  93       ++it_other;
  94     if (it_this == end() || it_other == other.end())
  95       break;
  96     if (it_this->first != it_other->first ||
  97         !it_this->second->Equals(*it_other->second)) {
  98       return false;
  99     }
 100     ++it_this;
 101     ++it_other;
 102   }
 103   return it_this == end() && it_other == other.end();
 104 }
 105
 106 void PolicyBundle::Clear() {
 107   STLDeleteValues(&policy_bundle_);
 108 }
 109
 110 }  // namespace policy