xref: /aosp_15_r20/external/drm_hwcomposer/utils/properties.h (revision 0a9764fe0a15e71ebbeb85e87e10990c23aab47f)
1 /*
2  * Copyright (C) 2022 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 #ifdef ANDROID
20 
21 #include <cutils/properties.h>
22 
23 #else
24 
25 #include <cstdio>
26 #include <cstdlib>
27 #include <cstring>
28 
29 // NOLINTNEXTLINE(readability-identifier-naming)
30 constexpr int PROPERTY_VALUE_MAX = 92;
31 
32 // NOLINTNEXTLINE(readability-identifier-naming)
33 auto inline property_get(const char *name, char *value,
34                          const char *default_value) -> int {
35   // NOLINTNEXTLINE (concurrency-mt-unsafe)
36   char *prop = std::getenv(name);
37   snprintf(value, PROPERTY_VALUE_MAX, "%s",
38            (prop == nullptr) ? default_value : prop);
39   return static_cast<int>(strlen(value));
40 }
41 
42 /**
43  * Bluntly copied from system/core/libcutils/properties.cpp,
44  * which is part of the Android Project and licensed under Apache 2.
45  * Source:
46  * https://cs.android.com/android/platform/superproject/main/+/main:system/core/libcutils/properties.cpp;l=27
47  */
48 auto inline property_get_bool(const char *key, int8_t default_value) -> int8_t {
49   if (!key)
50     return default_value;
51 
52   int8_t result = default_value;
53   char buf[PROPERTY_VALUE_MAX] = {};
54 
55   int len = property_get(key, buf, "");
56   if (len == 1) {
57     char ch = buf[0];
58     if (ch == '0' || ch == 'n') {
59       result = false;
60     } else if (ch == '1' || ch == 'y') {
61       result = true;
62     }
63   } else if (len > 1) {
64     if (!strcmp(buf, "no") || !strcmp(buf, "false") || !strcmp(buf, "off")) {
65       result = false;
66     } else if (!strcmp(buf, "yes") || !strcmp(buf, "true") ||
67                !strcmp(buf, "on")) {
68       result = true;
69     }
70   }
71 
72   return result;
73 }
74 
75 #endif
76 
77 class Properties {
78  public:
79   static auto IsPresentFenceNotReliable() -> bool;
80   static auto UseConfigGroups() -> bool;
81 };
82