blob: d8e7efb68620967af4639a38dfad75ec346d804b [file] [log] [blame]
// Copyright (c) 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.
#include "ui/gfx/sequential_id_generator.h"
#include "base/check_op.h"
namespace {
// Removes |key| from |first|, and |first[key]| from |second|.
template <typename T>
void Remove(uint32_t key, T* first, T* second) {
auto iter = first->find(key);
if (iter == first->end())
return;
uint32_t second_key = iter->second;
first->erase(iter);
iter = second->find(second_key);
DCHECK(iter != second->end());
second->erase(iter);
}
} // namespace
namespace ui {
SequentialIDGenerator::SequentialIDGenerator(uint32_t min_id)
: min_id_(min_id), min_available_id_(min_id) {}
SequentialIDGenerator::~SequentialIDGenerator() {
}
uint32_t SequentialIDGenerator::GetGeneratedID(uint32_t number) {
auto find = number_to_id_.find(number);
if (find != number_to_id_.end())
return find->second;
int id = GetNextAvailableID();
number_to_id_.emplace(number, id);
id_to_number_.emplace(id, number);
return id;
}
bool SequentialIDGenerator::HasGeneratedIDFor(uint32_t number) const {
return number_to_id_.find(number) != number_to_id_.end();
}
void SequentialIDGenerator::ReleaseNumber(uint32_t number) {
if (number_to_id_.count(number) > 0U) {
UpdateNextAvailableIDAfterRelease(number_to_id_[number]);
Remove(number, &number_to_id_, &id_to_number_);
}
}
void SequentialIDGenerator::ReleaseID(uint32_t id) {
if (id_to_number_.count(id) > 0U) {
UpdateNextAvailableIDAfterRelease(id);
Remove(id_to_number_[id], &number_to_id_, &id_to_number_);
}
}
void SequentialIDGenerator::ResetForTest() {
number_to_id_.clear();
id_to_number_.clear();
min_available_id_ = min_id_;
}
uint32_t SequentialIDGenerator::GetNextAvailableID() {
const uint32_t kMaxID = 128;
while (id_to_number_.count(min_available_id_) > 0 &&
min_available_id_ < kMaxID) {
++min_available_id_;
}
if (min_available_id_ >= kMaxID)
min_available_id_ = min_id_;
return min_available_id_;
}
void SequentialIDGenerator::UpdateNextAvailableIDAfterRelease(uint32_t id) {
if (id < min_available_id_) {
min_available_id_ = id;
DCHECK_GE(min_available_id_, min_id_);
}
}
} // namespace ui