xref: /aosp_15_r20/frameworks/native/libs/ui/include/ui/LogicalDisplayId.h (revision 38e8c45f13ce32b0dcecb25141ffecaf386fa17f)
1 /*
2  * Copyright 2024 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #pragma once
18 
19 #include <ftl/mixins.h>
20 #include <sys/types.h>
21 #include <string>
22 
23 #include <ostream>
24 
25 namespace android::ui {
26 
27 // Type-safe wrapper for a logical display id.
28 struct LogicalDisplayId : ftl::Constructible<LogicalDisplayId, int32_t>,
29                           ftl::Equatable<LogicalDisplayId>,
30                           ftl::Orderable<LogicalDisplayId> {
31     using Constructible::Constructible;
32 
valLogicalDisplayId33     constexpr auto val() const { return ftl::to_underlying(*this); }
34 
isValidLogicalDisplayId35     constexpr bool isValid() const { return val() >= 0; }
36 
toStringLogicalDisplayId37     std::string toString() const { return std::to_string(val()); }
38 
39     static const LogicalDisplayId INVALID;
40     static const LogicalDisplayId DEFAULT;
41 };
42 
43 constexpr inline LogicalDisplayId LogicalDisplayId::INVALID{-1};
44 constexpr inline LogicalDisplayId LogicalDisplayId::DEFAULT{0};
45 
46 inline std::ostream& operator<<(std::ostream& stream, LogicalDisplayId displayId) {
47     return stream << displayId.val();
48 }
49 
50 } // namespace android::ui
51 
52 namespace std {
53 template <>
54 struct hash<android::ui::LogicalDisplayId> {
55     size_t operator()(const android::ui::LogicalDisplayId& displayId) const {
56         return hash<int32_t>()(displayId.val());
57     }
58 };
59 } // namespace std