1 /*
2 * Copyright (C) 2019 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 #pragma once
17
18 #include <fstream>
19 #include <map>
20 #include <sstream>
21
22 #include <android-base/macros.h>
23 #include <android-base/properties.h>
24 #include <log/log.h>
25
26 namespace aidl {
27 namespace android {
28 namespace hardware {
29 namespace vibrator {
30 namespace utils {
31
32 template <typename T>
33 class Is_Iterable {
34 private:
35 template <typename U>
36 static std::true_type test(typename U::iterator *u);
37
38 template <typename U>
39 static std::false_type test(U *u);
40
41 public:
42 static const bool value = decltype(test<T>(0))::value;
43 };
44
45 template <typename T, bool B>
46 using Enable_If_Iterable = std::enable_if_t<Is_Iterable<T>::value == B>;
47
48 template <typename T, typename U = void>
49 using Enable_If_Signed = std::enable_if_t<std::is_signed_v<T>, U>;
50
51 template <typename T, typename U = void>
52 using Enable_If_Unsigned = std::enable_if_t<std::is_unsigned_v<T>, U>;
53
54 // override for default behavior of printing as a character
55 inline std::ostream &operator<<(std::ostream &stream, const int8_t value) {
56 return stream << +value;
57 }
58 // override for default behavior of printing as a character
59 inline std::ostream &operator<<(std::ostream &stream, const uint8_t value) {
60 return stream << +value;
61 }
62
63 template <typename T>
toUnderlying(const T value)64 inline auto toUnderlying(const T value) {
65 return static_cast<std::underlying_type_t<T>>(value);
66 }
67
68 template <typename T>
unpack(std::istream & stream,T * value)69 inline Enable_If_Iterable<T, true> unpack(std::istream &stream, T *value) {
70 for (auto &entry : *value) {
71 stream >> entry;
72 }
73 }
74
75 template <typename T>
unpack(std::istream & stream,T * value)76 inline Enable_If_Iterable<T, false> unpack(std::istream &stream, T *value) {
77 stream >> *value;
78 }
79
80 template <>
81 inline void unpack<std::string>(std::istream &stream, std::string *value) {
82 *value = std::string(std::istreambuf_iterator(stream), {});
83 stream.setstate(std::istream::eofbit);
84 }
85
86 template <typename T>
getProperty(const std::string & key,const T def)87 inline Enable_If_Signed<T, T> getProperty(const std::string &key, const T def) {
88 return ::android::base::GetIntProperty(key, def);
89 }
90
91 template <typename T>
getProperty(const std::string & key,const T def)92 inline Enable_If_Unsigned<T, T> getProperty(const std::string &key, const T def) {
93 return ::android::base::GetUintProperty(key, def);
94 }
95
96 template <>
97 inline bool getProperty<bool>(const std::string &key, const bool def) {
98 return ::android::base::GetBoolProperty(key, def);
99 }
100
101 template <typename T>
openNoCreate(const std::string & file,T * outStream)102 static void openNoCreate(const std::string &file, T *outStream) {
103 auto mode = std::is_base_of_v<std::ostream, T> ? std::ios_base::out : std::ios_base::in;
104
105 // Force 'in' mode to prevent file creation
106 outStream->open(file, mode | std::ios_base::in);
107 if (!*outStream) {
108 ALOGE("Failed to open %s (%d): %s", file.c_str(), errno, strerror(errno));
109 }
110 }
111
112 template <typename T>
113 static void fileFromEnv(const char *env, T *outStream, std::string *outName = nullptr) {
114 auto file = std::getenv(env);
115
116 if (file == nullptr) {
117 ALOGE("Failed get env %s", env);
118 return;
119 }
120
121 if (outName != nullptr) {
122 *outName = std::string(file);
123 }
124
125 openNoCreate(file, outStream);
126 }
127
128 static ATTRIBUTE_UNUSED auto pathsFromEnv(const char *env, const std::string &prefix = "") {
129 std::map<std::string, std::ifstream> ret;
130 auto value = std::getenv(env);
131
132 if (value == nullptr) {
133 return ret;
134 }
135
136 std::istringstream paths{value};
137 std::string path;
138
139 while (paths >> path) {
140 ret[path].open(prefix + path);
141 }
142
143 return ret;
144 }
145
146 static ATTRIBUTE_UNUSED std::string trim(const std::string &str,
147 const std::string &whitespace = " \t") {
148 const auto str_begin = str.find_first_not_of(whitespace);
149 if (str_begin == std::string::npos) {
150 return "";
151 }
152
153 const auto str_end = str.find_last_not_of(whitespace);
154 const auto str_range = str_end - str_begin + 1;
155
156 return str.substr(str_begin, str_range);
157 }
158
159 } // namespace utils
160 } // namespace vibrator
161 } // namespace hardware
162 } // namespace android
163 } // namespace aidl
164