chrome/common/extensions/value_counter.cc

   1 // Copyright (c) 2012 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 "chrome/common/extensions/value_counter.h"
   6
   7 #include "base/values.h"
   8
   9 #include <algorithm>
  10
  11 namespace extensions {
  12
  13 ValueCounter::ValueCounter() {
  14 }
  15
  16 ValueCounter::~ValueCounter() {
  17 }
  18
  19 ValueCounter::Entry::Entry(const base::Value& value)
  20     : value_(value.DeepCopy()),
  21       count_(1) {
  22 }
  23
  24 ValueCounter::Entry::~Entry() {
  25 }
  26
  27 int ValueCounter::Entry::Increment() {
  28   return ++count_;
  29 }
  30
  31 int ValueCounter::Entry::Decrement() {
  32   return --count_;
  33 }
  34
  35 int ValueCounter::Add(const base::Value& value) {
  36   return AddImpl(value, true);
  37 }
  38
  39 int ValueCounter::Remove(const base::Value& value) {
  40   for (EntryList::iterator it = entries_.begin(); it != entries_.end(); it++) {
  41     (*it)->value()->GetType();
  42     if ((*it)->value()->Equals(&value)) {
  43       int remaining = (*it)->Decrement();
  44       if (remaining == 0) {
  45         std::swap(*it, entries_.back());
  46         entries_.pop_back();
  47       }
  48       return remaining;
  49     }
  50   }
  51   return 0;
  52 }
  53
  54 int ValueCounter::AddIfMissing(const base::Value& value) {
  55   return AddImpl(value, false);
  56 }
  57
  58 int ValueCounter::AddImpl(const base::Value& value, bool increment) {
  59   for (EntryList::iterator it = entries_.begin(); it != entries_.end(); it++) {
  60     if ((*it)->value()->Equals(&value))
  61       return increment ? (*it)->Increment() : (*it)->count();
  62   }
  63   entries_.push_back(linked_ptr<Entry>(new Entry(value)));
  64   return 1;
  65 }
  66
  67 }  // namespace extensions