third_party/tcmalloc/chromium/src/base/commandlineflags.h

   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 of the pointer type.
 104 #define DECLARE_string(name)                                          \
 105   namespace FLAG__namespace_do_not_use_directly_use_DECLARE_string_instead {  \
 106   extern const char* FLAGS_##name;                                            \
 107   }                                                                           \
 108   using FLAG__namespace_do_not_use_directly_use_DECLARE_string_instead::FLAGS_##name
 109 #define DEFINE_string(name, value, meaning) \
 110   namespace FLAG__namespace_do_not_use_directly_use_DECLARE_string_instead {  \
 111   const char* FLAGS_##name = value;                                           \
 112   char FLAGS_no##name;                                                        \
 113   }                                                                           \
 114   using FLAG__namespace_do_not_use_directly_use_DECLARE_string_instead::FLAGS_##name
 115
 116 // These macros (could be functions, but I don't want to bother with a .cc
 117 // file), make it easier to initialize flags from the environment.
 118 // They are functions in Android because __system_property_get() doesn't
 119 // return a string.
 120
 121 #if defined(ENABLE_PROFILING)
 122
 123 #if defined(__ANDROID__) || defined(ANDROID)
 124
 125 // Returns a pointer to a static variable.  The string pointed by the returned
 126 // pointer must not be modified.
 127 inline const char* const EnvToString(const char* envname, const char* dflt) {
 128   static char system_property_value[PROP_VALUE_MAX];
 129   if (__system_property_get(envname, system_property_value) > 0)
 130     return system_property_value;
 131   return dflt;
 132 }
 133
 134 inline bool EnvToBool(const char* envname, bool dflt) {
 135   static const char kTrueValues[] = "tTyY1";
 136   char system_property_value[PROP_VALUE_MAX];
 137   if (__system_property_get(envname, system_property_value) > 0)
 138     return memchr(kTrueValues, system_property_value[0], sizeof(kTrueValues));
 139   return dflt;
 140 }
 141
 142 inline int EnvToInt(const char* envname, int dflt) {
 143   char system_property_value[PROP_VALUE_MAX];
 144   if (__system_property_get(envname, system_property_value) > 0)
 145     return strtol(system_property_value, NULL, 10);
 146   return dflt;
 147 }
 148
 149 inline int64 EnvToInt64(const char* envname, int64 dflt) {
 150   char system_property_value[PROP_VALUE_MAX];
 151   if (__system_property_get(envname, system_property_value) > 0)
 152     return strtoll(system_property_value, NULL, 10);
 153   return dflt;
 154 }
 155
 156 inline double EnvToDouble(const char* envname, double dflt) {
 157   char system_property_value[PROP_VALUE_MAX];
 158   if (__system_property_get(envname, system_property_value) > 0)
 159     return strtod(system_property_value, NULL);
 160   return dflt;
 161 }
 162
 163 #else  // defined(__ANDROID__) || defined(ANDROID)
 164
 165 #define EnvToString(envname, dflt)   \
 166   (!getenv(envname) ? (dflt) : getenv(envname))
 167
 168 #define EnvToBool(envname, dflt)   \
 169   (!getenv(envname) ? (dflt) : memchr("tTyY1\0", getenv(envname)[0], 6) != NULL)
 170
 171 #define EnvToInt(envname, dflt)  \
 172   (!getenv(envname) ? (dflt) : strtol(getenv(envname), NULL, 10))
 173
 174 #define EnvToInt64(envname, dflt)  \
 175   (!getenv(envname) ? (dflt) : strtoll(getenv(envname), NULL, 10))
 176
 177 #define EnvToDouble(envname, dflt)  \
 178   (!getenv(envname) ? (dflt) : strtod(getenv(envname), NULL))
 179
 180 #endif  // defined(__ANDROID__) || defined(ANDROID)
 181
 182 #else  // defined(ENABLE_PROFILING)
 183
 184 #define EnvToString(envname, dflt) (dflt)
 185 #define EnvToBool(envname, dflt) (dflt)
 186 #define EnvToInt(envname, dflt) (dflt)
 187 #define EnvToInt64(envname, dflt) (dflt)
 188 #define EnvToDouble(envname, dflt) (dflt)
 189
 190 #endif  // defined(ENABLE_PROFILING)
 191
 192 #endif  // BASE_COMMANDLINEFLAGS_H_