1 /* 2 * Copyright 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 <limits.h> 20 #include <string.h> 21 #include <charconv> 22 #include <iomanip> 23 #include <iterator> 24 #include <limits> 25 #include <optional> 26 #include <sstream> 27 #include <string> 28 #include <type_traits> 29 #include <vector> 30 31 #include "common/type_helper.h" 32 #include "os/log.h" 33 34 namespace bluetooth { 35 namespace common { 36 37 // Convert number into a hex string prefixed with 0x 38 template <typename T> 39 std::string ToHexString(T x) { 40 if (x < 0) { 41 if (x == INT_MIN) return "INT_MIN"; 42 return "-" + ToHexString(-x); 43 } 44 std::stringstream tmp; 45 tmp << "0x" << std::internal << std::hex << std::setfill('0') << std::setw(sizeof(T) * 2) << (unsigned long)x; 46 return tmp.str(); 47 } 48 49 template <> 50 inline std::string ToHexString<signed long>(signed long x) { 51 if (x < 0) { 52 if (x == LONG_MIN) return "LONG_MIN"; 53 return "-" + ToHexString<signed long>(-x); 54 } 55 std::stringstream tmp; 56 tmp << "0x" << std::internal << std::hex << std::setfill('0') << std::setw(sizeof(signed long) * 2) 57 << (unsigned long)x; 58 return tmp.str(); 59 } 60 61 // Convert value into a hex decimal formatted string in lower case, prefixed with 0s 62 template <class InputIt> 63 std::string ToHexString(InputIt first, InputIt last) { 64 static_assert( 65 std::is_same_v<typename std::iterator_traits<InputIt>::value_type, uint8_t>, "Must use uint8_t iterator"); 66 std::stringstream ss; 67 for (InputIt it = first; it != last; ++it) { 68 // +(byte) to prevent an uint8_t to be interpreted as a char 69 ss << std::hex << std::setw(2) << std::setfill('0') << +(*it); 70 } 71 return ss.str(); 72 } 73 // Convenience method for normal cases and initializer list, e.g. ToHexString({0x12, 0x34, 0x56, 0xab}) 74 std::string ToHexString(const std::vector<uint8_t>& value); 75 76 // Return true if |str| is a valid hex demical strings contains only hex decimal chars [0-9a-fA-F] 77 bool IsValidHexString(const std::string& str); 78 79 // Parse |str| into a vector of uint8_t, |str| must contains only hex decimal 80 std::optional<std::vector<uint8_t>> FromHexString(const std::string& str); 81 82 // Remove whitespace from both ends of the |str|, returning a copy 83 std::string StringTrim(std::string str); 84 85 // Split |str| into at most |max_token| tokens delimited by |delim|, unlimited tokens when |max_token| is 0 86 std::vector<std::string> StringSplit(const std::string& str, const std::string& delim, size_t max_token = 0); 87 88 // Join |strings| into a single string using |delim| 89 std::string StringJoin(const std::vector<std::string>& strings, const std::string& delim); 90 91 // Various number comparison functions, only base 10 is supported 92 std::optional<int64_t> Int64FromString(const std::string& str); 93 std::string ToString(int64_t value); 94 std::optional<uint64_t> Uint64FromString(const std::string& str); 95 std::string ToString(uint64_t value); 96 std::optional<bool> BoolFromString(const std::string& str); 97 std::string ToString(bool value); 98 99 // printf like formatting to std::string 100 // format must contains format information, to print a string use StringFormat("%s", str) 101 template <typename... Args> 102 std::string StringFormat(const std::string& format, Args... args) { 103 auto size = std::snprintf(nullptr, 0, format.c_str(), args...); 104 ASSERT_LOG(size >= 0, "return value %d, error %d, text '%s'", size, errno, strerror(errno)); 105 // Add 1 for terminating null byte 106 char buffer[size + 1]; 107 auto actual_size = std::snprintf(buffer, sizeof(buffer), format.c_str(), args...); 108 ASSERT_LOG( 109 size == actual_size, 110 "asked size %d, actual size %d, error %d, text '%s'", 111 size, 112 actual_size, 113 errno, 114 strerror(errno)); 115 // Exclude the terminating null byte 116 return std::string(buffer, size); 117 } 118 119 inline std::string StringFormatTime(const std::string& format, const struct std::tm& tm) { 120 std::ostringstream os; 121 os << std::put_time(&tm, format.c_str()); 122 return os.str(); 123 } 124 125 inline std::string StringFormatTimeWithMilliseconds( 126 const std::string& format, 127 std::chrono::time_point<std::chrono::system_clock> time_point, 128 struct tm* (*calendar_to_tm)(const time_t* timep) = localtime) { 129 std::time_t epoch_time = std::chrono::system_clock::to_time_t(time_point); 130 auto millis = time_point.time_since_epoch() / std::chrono::milliseconds(1) % 1000; 131 std::tm tm = *calendar_to_tm(&epoch_time); 132 std::ostringstream os; 133 os << std::put_time(&tm, format.c_str()) << StringFormat(".%03u", millis); 134 return os.str(); 135 } 136 137 } // namespace common 138 } // namespace bluetooth 139