1 // Copyright (c) 2005, Google Inc. 2 // All rights reserved. 3 // 4 // Redistribution and use in source and binary forms, with or without 5 // modification, are permitted provided that the following conditions are 6 // met: 7 // 8 // * Redistributions of source code must retain the above copyright 9 // notice, this list of conditions and the following disclaimer. 10 // * Redistributions in binary form must reproduce the above 11 // copyright notice, this list of conditions and the following disclaimer 12 // in the documentation and/or other materials provided with the 13 // distribution. 14 // * Neither the name of Google Inc. nor the names of its 15 // contributors may be used to endorse or promote products derived from 16 // this software without specific prior written permission. 17 // 18 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 19 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 20 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 21 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 22 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 23 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 24 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 28 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 30 // --- 31 // This file is a compatibility layer that defines Google's version of 32 // command line flags that are used for configuration. 33 // 34 // We put flags into their own namespace. It is purposefully 35 // named in an opaque way that people should have trouble typing 36 // directly. The idea is that DEFINE puts the flag in the weird 37 // namespace, and DECLARE imports the flag from there into the 38 // current namespace. The net result is to force people to use 39 // DECLARE to get access to a flag, rather than saying 40 // extern bool FLAGS_logtostderr; 41 // or some such instead. We want this so we can put extra 42 // functionality (like sanity-checking) in DECLARE if we want, 43 // and make sure it is picked up everywhere. 44 // 45 // We also put the type of the variable in the namespace, so that 46 // people can't DECLARE_int32 something that they DEFINE_bool'd 47 // elsewhere. 48 #ifndef BASE_COMMANDLINEFLAGS_H_ 49 #define BASE_COMMANDLINEFLAGS_H_ 50 51 #include <config.h> 52 #include <string> 53 #include <string.h> // for memchr 54 #include <stdlib.h> // for getenv 55 #include "base/basictypes.h" 56 57 #if defined(__ANDROID__) || defined(ANDROID) 58 #include <sys/system_properties.h> 59 #endif 60 61 #define DECLARE_VARIABLE(type, name) \ 62 namespace FLAG__namespace_do_not_use_directly_use_DECLARE_##type##_instead { \ 63 extern PERFTOOLS_DLL_DECL type FLAGS_##name; \ 64 } \ 65 using FLAG__namespace_do_not_use_directly_use_DECLARE_##type##_instead::FLAGS_##name 66 67 #define DEFINE_VARIABLE(type, name, value, meaning) \ 68 namespace FLAG__namespace_do_not_use_directly_use_DECLARE_##type##_instead { \ 69 PERFTOOLS_DLL_DECL type FLAGS_##name(value); \ 70 char FLAGS_no##name; \ 71 } \ 72 using FLAG__namespace_do_not_use_directly_use_DECLARE_##type##_instead::FLAGS_##name 73 74 // bool specialization 75 #define DECLARE_bool(name) \ 76 DECLARE_VARIABLE(bool, name) 77 #define DEFINE_bool(name, value, meaning) \ 78 DEFINE_VARIABLE(bool, name, value, meaning) 79 80 // int32 specialization 81 #define DECLARE_int32(name) \ 82 DECLARE_VARIABLE(int32, name) 83 #define DEFINE_int32(name, value, meaning) \ 84 DEFINE_VARIABLE(int32, name, value, meaning) 85 86 // int64 specialization 87 #define DECLARE_int64(name) \ 88 DECLARE_VARIABLE(int64, name) 89 #define DEFINE_int64(name, value, meaning) \ 90 DEFINE_VARIABLE(int64, name, value, meaning) 91 92 #define DECLARE_uint64(name) \ 93 DECLARE_VARIABLE(uint64, name) 94 #define DEFINE_uint64(name, value, meaning) \ 95 DEFINE_VARIABLE(uint64, name, value, meaning) 96 97 // double specialization 98 #define DECLARE_double(name) \ 99 DECLARE_VARIABLE(double, name) 100 #define DEFINE_double(name, value, meaning) \ 101 DEFINE_VARIABLE(double, name, value, meaning) 102 103 // Special case for string, because we have to specify the namespace 104 // std::string, which doesn't play nicely with our FLAG__namespace hackery. 105 #define DECLARE_string(name) \ 106 namespace FLAG__namespace_do_not_use_directly_use_DECLARE_string_instead { \ 107 extern std::string FLAGS_##name; \ 108 } \ 109 using FLAG__namespace_do_not_use_directly_use_DECLARE_string_instead::FLAGS_##name 110 #define DEFINE_string(name, value, meaning) \ 111 namespace FLAG__namespace_do_not_use_directly_use_DECLARE_string_instead { \ 112 std::string FLAGS_##name(value); \ 113 char FLAGS_no##name; \ 114 } \ 115 using FLAG__namespace_do_not_use_directly_use_DECLARE_string_instead::FLAGS_##name 116 117 // These macros (could be functions, but I don't want to bother with a .cc 118 // file), make it easier to initialize flags from the environment. 119 // They are functions in Android because __system_property_get() doesn't 120 // return a string. 121 122 #if defined(__ANDROID__) || defined(ANDROID) 123 124 // Returns a pointer to a static variable. The string pointed by the returned 125 // pointer must not be modified. 126 inline const char* const EnvToString(const char* envname, const char* dflt) { 127 static char system_property_value[PROP_VALUE_MAX]; 128 if (__system_property_get(envname, system_property_value) > 0) 129 return system_property_value; 130 return dflt; 131 } 132 133 inline bool EnvToBool(const char* envname, bool dflt) { 134 static const char kTrueValues[] = "tTyY1"; 135 char system_property_value[PROP_VALUE_MAX]; 136 if (__system_property_get(envname, system_property_value) > 0) 137 return memchr(kTrueValues, system_property_value[0], sizeof(kTrueValues)); 138 return dflt; 139 } 140 141 inline int EnvToInt(const char* envname, int dflt) { 142 char system_property_value[PROP_VALUE_MAX]; 143 if (__system_property_get(envname, system_property_value) > 0) 144 return strtol(system_property_value, NULL, 10); 145 return dflt; 146 } 147 148 inline int64 EnvToInt64(const char* envname, int64 dflt) { 149 char system_property_value[PROP_VALUE_MAX]; 150 if (__system_property_get(envname, system_property_value) > 0) 151 return strtoll(system_property_value, NULL, 10); 152 return dflt; 153 } 154 155 inline double EnvToDouble(const char* envname, double dflt) { 156 char system_property_value[PROP_VALUE_MAX]; 157 if (__system_property_get(envname, system_property_value) > 0) 158 return strtod(system_property_value, NULL); 159 return dflt; 160 } 161 162 #else // defined(__ANDROID__) || defined(ANDROID) 163 164 #define EnvToString(envname, dflt) \ 165 (!getenv(envname) ? (dflt) : getenv(envname)) 166 167 #define EnvToBool(envname, dflt) \ 168 (!getenv(envname) ? (dflt) : memchr("tTyY1\0", getenv(envname)[0], 6) != NULL) 169 170 #define EnvToInt(envname, dflt) \ 171 (!getenv(envname) ? (dflt) : strtol(getenv(envname), NULL, 10)) 172 173 #define EnvToInt64(envname, dflt) \ 174 (!getenv(envname) ? (dflt) : strtoll(getenv(envname), NULL, 10)) 175 176 #define EnvToDouble(envname, dflt) \ 177 (!getenv(envname) ? (dflt) : strtod(getenv(envname), NULL)) 178 179 #endif // defined(__ANDROID__) || defined(ANDROID) 180 181 #endif // BASE_COMMANDLINEFLAGS_H_ 182