1 /*
2 * Copyright (C) 2011 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 #ifndef ART_LIBARTBASE_BASE_UTILS_H_
18 #define ART_LIBARTBASE_BASE_UTILS_H_
19
20 #include <pthread.h>
21 #include <stdlib.h>
22
23 #include <random>
24 #include <string>
25
26 #include <android-base/logging.h>
27 #include <android-base/parseint.h>
28
29 #include "casts.h"
30 #include "enums.h"
31 #include "globals.h"
32 #include "macros.h"
33
34 namespace art {
35
PointerToLowMemUInt32(const void * p)36 static inline uint32_t PointerToLowMemUInt32(const void* p) {
37 uintptr_t intp = reinterpret_cast<uintptr_t>(p);
38 DCHECK_LE(intp, 0xFFFFFFFFU);
39 return intp & 0xFFFFFFFFU;
40 }
41
42 // Returns a human-readable size string such as "1MB".
43 std::string PrettySize(int64_t size_in_bytes);
44
45 // Splits a string using the given separator character into a vector of
46 // strings. Empty strings will be omitted.
47 void Split(const std::string& s, char separator, std::vector<std::string>* result);
48
49 // Returns the calling thread's tid. (The C libraries don't expose this.)
50 pid_t GetTid();
51
52 // Returns the given thread's name.
53 std::string GetThreadName(pid_t tid);
54
55 // Sets the name of the current thread. The name may be truncated to an
56 // implementation-defined limit.
57 void SetThreadName(const char* thread_name);
58
59 // Reads data from "/proc/self/task/${tid}/stat".
60 void GetTaskStats(pid_t tid, char* state, int* utime, int* stime, int* task_cpu);
61
62 class VoidFunctor {
63 public:
64 template <typename A>
operator()65 inline void operator() (A a ATTRIBUTE_UNUSED) const {
66 }
67
68 template <typename A, typename B>
operator()69 inline void operator() (A a ATTRIBUTE_UNUSED, B b ATTRIBUTE_UNUSED) const {
70 }
71
72 template <typename A, typename B, typename C>
operator()73 inline void operator() (A a ATTRIBUTE_UNUSED, B b ATTRIBUTE_UNUSED, C c ATTRIBUTE_UNUSED) const {
74 }
75 };
76
TestBitmap(size_t idx,const uint8_t * bitmap)77 inline bool TestBitmap(size_t idx, const uint8_t* bitmap) {
78 return ((bitmap[idx / kBitsPerByte] >> (idx % kBitsPerByte)) & 0x01) != 0;
79 }
80
ValidPointerSize(size_t pointer_size)81 static inline constexpr bool ValidPointerSize(size_t pointer_size) {
82 return pointer_size == 4 || pointer_size == 8;
83 }
84
EntryPointToCodePointer(const void * entry_point)85 static inline const void* EntryPointToCodePointer(const void* entry_point) {
86 uintptr_t code = reinterpret_cast<uintptr_t>(entry_point);
87 // TODO: Make this Thumb2 specific. It is benign on other architectures as code is always at
88 // least 2 byte aligned.
89 code &= ~0x1;
90 return reinterpret_cast<const void*>(code);
91 }
92
93 #if defined(__BIONIC__)
94 struct Arc4RandomGenerator {
95 typedef uint32_t result_type;
minArc4RandomGenerator96 static constexpr uint32_t min() { return std::numeric_limits<uint32_t>::min(); }
maxArc4RandomGenerator97 static constexpr uint32_t max() { return std::numeric_limits<uint32_t>::max(); }
operatorArc4RandomGenerator98 uint32_t operator() () { return arc4random(); }
99 };
100 using RNG = Arc4RandomGenerator;
101 #else
102 using RNG = std::random_device;
103 #endif
104
105 template <typename T>
GetRandomNumber(T min,T max)106 static T GetRandomNumber(T min, T max) {
107 CHECK_LT(min, max);
108 std::uniform_int_distribution<T> dist(min, max);
109 RNG rng;
110 return dist(rng);
111 }
112
113 // Sleep forever and never come back.
114 NO_RETURN void SleepForever();
115
116 // Flush CPU caches. Returns true on success, false if flush failed.
117 WARN_UNUSED bool FlushCpuCaches(void* begin, void* end);
118
119 template <typename T>
ConvertToPointerSize(T any)120 constexpr PointerSize ConvertToPointerSize(T any) {
121 if (any == 4 || any == 8) {
122 return static_cast<PointerSize>(any);
123 } else {
124 LOG(FATAL);
125 UNREACHABLE();
126 }
127 }
128
129 // Return -1 if <, 0 if ==, 1 if >.
130 template <typename T>
Compare(T lhs,T rhs)131 inline static int32_t Compare(T lhs, T rhs) {
132 return (lhs < rhs) ? -1 : ((lhs == rhs) ? 0 : 1);
133 }
134
135 // Return -1 if < 0, 0 if == 0, 1 if > 0.
136 template <typename T>
Signum(T opnd)137 inline static int32_t Signum(T opnd) {
138 return (opnd < 0) ? -1 : ((opnd == 0) ? 0 : 1);
139 }
140
141 template <typename Func, typename... Args>
CheckedCall(const Func & function,const char * what,Args...args)142 static inline void CheckedCall(const Func& function, const char* what, Args... args) {
143 int rc = function(args...);
144 if (UNLIKELY(rc != 0)) {
145 PLOG(FATAL) << "Checked call failed for " << what;
146 }
147 }
148
149 // Lookup value for a given key in /proc/self/status. Keys and values are separated by a ':' in
150 // the status file. Returns value found on success and "<unknown>" if the key is not found or
151 // there is an I/O error.
152 std::string GetProcessStatus(const char* key);
153
154 } // namespace art
155
156 #endif // ART_LIBARTBASE_BASE_UTILS_H_
157