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 <android-base/macros.h>
19 #include <android-base/parsedouble.h>
20 #include <android-base/properties.h>
21 #include <log/log.h>
22
23 #include <fstream>
24 #include <map>
25 #include <sstream>
26
27 namespace aidl {
28 namespace android {
29 namespace hardware {
30 namespace vibrator {
31 namespace utils {
32
33 template <typename T>
34 class Is_Iterable {
35 private:
36 template <typename U>
37 static std::true_type test(typename U::iterator *u);
38
39 template <typename U>
40 static std::false_type test(U *u);
41
42 public:
43 static const bool value = decltype(test<T>(0))::value;
44 };
45
46 template <typename T, bool B>
47 using Enable_If_Iterable = std::enable_if_t<Is_Iterable<T>::value == B>;
48
49 template <typename T, typename U = void>
50 using Enable_If_Signed = std::enable_if_t<std::is_signed_v<T>, U>;
51
52 template <typename T, typename U = void>
53 using Enable_If_Unsigned = std::enable_if_t<std::is_unsigned_v<T>, U>;
54
55 // override for default behavior of printing as a character
56 inline std::ostream &operator<<(std::ostream &stream, const int8_t value) {
57 return stream << +value;
58 }
59 // override for default behavior of printing as a character
60 inline std::ostream &operator<<(std::ostream &stream, const uint8_t value) {
61 return stream << +value;
62 }
63
64 template <typename T>
toUnderlying(const T value)65 inline auto toUnderlying(const T value) {
66 return static_cast<std::underlying_type_t<T>>(value);
67 }
68
69 template <typename T>
unpack(std::istream & stream,T * value)70 inline Enable_If_Iterable<T, true> unpack(std::istream &stream, T *value) {
71 for (auto &entry : *value) {
72 stream >> entry;
73 }
74 }
75
76 template <typename T>
unpack(std::istream & stream,T * value)77 inline Enable_If_Iterable<T, false> unpack(std::istream &stream, T *value) {
78 stream >> *value;
79 }
80
81 template <>
82 inline void unpack<std::string>(std::istream &stream, std::string *value) {
83 *value = std::string(std::istreambuf_iterator(stream), {});
84 stream.setstate(std::istream::eofbit);
85 }
86
87 template <typename T>
getProperty(const std::string & key,const T def)88 inline Enable_If_Signed<T, T> getProperty(const std::string &key, const T def) {
89 if (std::is_floating_point_v<T>) {
90 float result;
91 std::string value = ::android::base::GetProperty(key, "");
92 if (!value.empty() && ::android::base::ParseFloat(value, &result)) {
93 return result;
94 }
95 return def;
96 } else {
97 return ::android::base::GetIntProperty(key, def);
98 }
99 }
100
101 template <typename T>
getProperty(const std::string & key,const T def)102 inline Enable_If_Unsigned<T, T> getProperty(const std::string &key, const T def) {
103 return ::android::base::GetUintProperty(key, def);
104 }
105
106 template <typename T, size_t N>
getProperty(const std::string & key,const std::array<T,N> & def)107 inline std::array<T, N> getProperty(const std::string &key, const std::array<T, N> &def) {
108 std::string value = ::android::base::GetProperty(key, "");
109 if (!value.empty()) {
110 std::array<T, N> result{0};
111 std::stringstream stream{value};
112 utils::unpack(stream, &result);
113 if (stream && stream.eof())
114 return result;
115 }
116 return def;
117 }
118
119 template <>
120 inline bool getProperty<bool>(const std::string &key, const bool def) {
121 return ::android::base::GetBoolProperty(key, def);
122 }
123
124 template <typename T>
openNoCreate(const std::string & file,T * outStream)125 static void openNoCreate(const std::string &file, T *outStream) {
126 auto mode = std::is_base_of_v<std::ostream, T> ? std::ios_base::out : std::ios_base::in;
127
128 // Force 'in' mode to prevent file creation
129 outStream->open(file, mode | std::ios_base::in);
130 if (!*outStream) {
131 ALOGE("Failed to open %s (%d): %s", file.c_str(), errno, strerror(errno));
132 }
133 }
134
135 template <typename T>
136 static void fileFromEnv(const char *env, T *outStream, std::string *outName = nullptr) {
137 auto file = std::getenv(env);
138
139 if (file == nullptr) {
140 ALOGE("Failed get env %s", env);
141 return;
142 }
143
144 if (outName != nullptr) {
145 *outName = std::string(file);
146 }
147
148 openNoCreate(file, outStream);
149 }
150
151 static ATTRIBUTE_UNUSED auto pathsFromEnv(const char *env, const std::string &prefix = "") {
152 std::map<std::string, std::ifstream> ret;
153 auto value = std::getenv(env);
154
155 if (value == nullptr) {
156 return ret;
157 }
158
159 std::istringstream paths{value};
160 std::string path;
161
162 while (paths >> path) {
163 ret[path].open(prefix + path);
164 }
165
166 return ret;
167 }
168
169 static ATTRIBUTE_UNUSED std::string trim(const std::string &str,
170 const std::string &whitespace = " \t") {
171 const auto str_begin = str.find_first_not_of(whitespace);
172 if (str_begin == std::string::npos) {
173 return "";
174 }
175
176 const auto str_end = str.find_last_not_of(whitespace);
177 const auto str_range = str_end - str_begin + 1;
178
179 return str.substr(str_begin, str_range);
180 }
181
182 } // namespace utils
183 } // namespace vibrator
184 } // namespace hardware
185 } // namespace android
186 } // namespace aidl
187