1 /*
2 * Copyright (C) 2020 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 <stddef.h>
20 #include <sys/uio.h>
21 #include <chrono>
22 #include <cstdint>
23 #include <optional>
24
25 #include <binder/Common.h>
26 #include <log/log.h>
27 #include <utils/Errors.h>
28
29 #define PLOGE(fmt, ...) \
30 do { \
31 auto savedErrno = errno; \
32 ALOGE(fmt ": %s" __VA_OPT__(, ) __VA_ARGS__, strerror(savedErrno)); \
33 } while (0)
34 #define PLOGF(fmt, ...) \
35 do { \
36 auto savedErrno = errno; \
37 LOG_ALWAYS_FATAL(fmt ": %s" __VA_OPT__(, ) __VA_ARGS__, strerror(savedErrno)); \
38 } while (0)
39
40 /* TEMP_FAILURE_RETRY is not available on macOS and Trusty. */
41 #ifndef TEMP_FAILURE_RETRY
42 /* Used to retry syscalls that can return EINTR. */
43 #define TEMP_FAILURE_RETRY(exp) \
44 ({ \
45 __typeof__(exp) _rc; \
46 do { \
47 _rc = (exp); \
48 } while (_rc == -1 && errno == EINTR); \
49 _rc; \
50 })
51 #endif
52
53 #define TEST_AND_RETURN(value, expr) \
54 do { \
55 if (!(expr)) { \
56 ALOGE("Failed to call: %s", #expr); \
57 return value; \
58 } \
59 } while (0)
60
61 #define LIBBINDER_PRAGMA(arg) _Pragma(#arg)
62 #if defined(__clang__)
63 #define LIBBINDER_PRAGMA_FOR_COMPILER(arg) LIBBINDER_PRAGMA(clang arg)
64 #elif defined(__GNUC__)
65 #define LIBBINDER_PRAGMA_FOR_COMPILER(arg) LIBBINDER_PRAGMA(GCC arg)
66 #else
67 #define LIBBINDER_PRAGMA_FOR_COMPILER(arg)
68 #endif
69 #define LIBBINDER_IGNORE(warning_flag) \
70 LIBBINDER_PRAGMA_FOR_COMPILER(diagnostic push) \
71 LIBBINDER_PRAGMA_FOR_COMPILER(diagnostic ignored warning_flag)
72 #define LIBBINDER_IGNORE_END() LIBBINDER_PRAGMA_FOR_COMPILER(diagnostic pop)
73
74 namespace android {
75
76 /**
77 * Get the size of a statically initialized array.
78 *
79 * \param N the array to get the size of.
80 * \return the size of the array.
81 */
82 template <typename T, size_t N>
countof(T (&)[N])83 constexpr size_t countof(T (&)[N]) {
84 return N;
85 }
86
87 // avoid optimizations
88 void zeroMemory(uint8_t* data, size_t size);
89
90 // View of contiguous sequence. Similar to std::span.
91 template <typename T>
92 struct Span {
93 T* data = nullptr;
94 size_t size = 0;
95
byteSizeSpan96 size_t byteSize() { return size * sizeof(T); }
97
toIovecSpan98 iovec toIovec() { return {const_cast<std::remove_const_t<T>*>(data), byteSize()}; }
99
100 // Truncates `this` to a length of `offset` and returns a span with the
101 // remainder.
102 //
103 // `std::nullopt` iff offset > size.
splitOffSpan104 std::optional<Span<T>> splitOff(size_t offset) {
105 if (offset > size) {
106 return std::nullopt;
107 }
108 Span<T> rest = {data + offset, size - offset};
109 size = offset;
110 return rest;
111 }
112
113 // Returns nullopt if the byte size of `this` isn't evenly divisible by sizeof(U).
114 template <typename U>
reinterpretSpan115 std::optional<Span<U>> reinterpret() const {
116 // Only allow casting from bytes for simplicity.
117 static_assert(std::is_same_v<std::remove_const_t<T>, uint8_t>);
118 if (size % sizeof(U) != 0) {
119 return std::nullopt;
120 }
121 return Span<U>{reinterpret_cast<U*>(data), size / sizeof(U)};
122 }
123 };
124
125 // Converts binary data into a hexString.
126 //
127 // Hex values are printed in order, e.g. 0xDEAD will result in 'adde' because
128 // Android is little-endian.
129 LIBBINDER_INTERNAL_EXPORTED std::string HexString(const void* bytes, size_t len);
130
131 // Converts any std::chrono duration to the number of milliseconds
132 template <class Rep, class Period>
to_ms(std::chrono::duration<Rep,Period> duration)133 uint64_t to_ms(std::chrono::duration<Rep, Period> duration) {
134 return std::chrono::duration_cast<std::chrono::milliseconds>(duration).count();
135 }
136
137 } // namespace android
138