[tcmalloc]: Remove calls to __system_property_get in tcmalloc.

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

 // Copyright (c) 2005, Google Inc.
 // All rights reserved.
 // 
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 // 
 //     * Redistributions of source code must retain the above copyright
 // notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
@@ skipping 36 matching lines @@
 // elsewhere.
 #ifndef BASE_COMMANDLINEFLAGS_H_
 #define BASE_COMMANDLINEFLAGS_H_
 
 #include <config.h>
 #include <string>
 #include <string.h>               // for memchr
 #include <stdlib.h>               // for getenv
 #include "base/basictypes.h"
 
-#if defined(__ANDROID__) || defined(ANDROID)
-#include <sys/system_properties.h>
-#endif
-
 #define DECLARE_VARIABLE(type, name)                                          \
   namespace FLAG__namespace_do_not_use_directly_use_DECLARE_##type##_instead {\
   extern PERFTOOLS_DLL_DECL type FLAGS_##name;                                \
   }                                                                           \
   using FLAG__namespace_do_not_use_directly_use_DECLARE_##type##_instead::FLAGS_##name
 
 #define DEFINE_VARIABLE(type, name, value, meaning) \
   namespace FLAG__namespace_do_not_use_directly_use_DECLARE_##type##_instead {\
   PERFTOOLS_DLL_DECL type FLAGS_##name(value);                                \
   char FLAGS_no##name;                                                        \
@@ skipping 37 matching lines @@
   using FLAG__namespace_do_not_use_directly_use_DECLARE_string_instead::FLAGS_##name
 #define DEFINE_string(name, value, meaning) \
   namespace FLAG__namespace_do_not_use_directly_use_DECLARE_string_instead {  \
   const char* FLAGS_##name = value;                                           \
   char FLAGS_no##name;                                                        \
   }                                                                           \
   using FLAG__namespace_do_not_use_directly_use_DECLARE_string_instead::FLAGS_##name
 
 // These macros (could be functions, but I don't want to bother with a .cc
 // file), make it easier to initialize flags from the environment.
-// They are functions in Android because __system_property_get() doesn't
-// return a string.
 
 #if defined(ENABLE_PROFILING)
 
 #if defined(__ANDROID__) || defined(ANDROID)
-
-// Returns a pointer to a static variable.  The string pointed by the returned
-// pointer must not be modified.
-inline const char* const EnvToString(const char* envname, const char* dflt) {
-  static char system_property_value[PROP_VALUE_MAX];
-  if (__system_property_get(envname, system_property_value) > 0)
-    return system_property_value;
-  return dflt;
-}
-
-inline bool EnvToBool(const char* envname, bool dflt) {
-  static const char kTrueValues[] = "tTyY1";
-  char system_property_value[PROP_VALUE_MAX];
-  if (__system_property_get(envname, system_property_value) > 0)
-    return memchr(kTrueValues, system_property_value[0], sizeof(kTrueValues));
-  return dflt;
-}
-
-inline int EnvToInt(const char* envname, int dflt) {
-  char system_property_value[PROP_VALUE_MAX];
-  if (__system_property_get(envname, system_property_value) > 0)
-    return strtol(system_property_value, NULL, 10);
-  return dflt;
-}
-
-inline int64 EnvToInt64(const char* envname, int64 dflt) {
-  char system_property_value[PROP_VALUE_MAX];
-  if (__system_property_get(envname, system_property_value) > 0)
-    return strtoll(system_property_value, NULL, 10);
-  return dflt;
-}
-
-inline double EnvToDouble(const char* envname, double dflt) {
-  char system_property_value[PROP_VALUE_MAX];
-  if (__system_property_get(envname, system_property_value) > 0)
-    return strtod(system_property_value, NULL);
-  return dflt;
-}
-
-#else  // defined(__ANDROID__) || defined(ANDROID)
+#error TCMalloc does not support profiling on Android

[jar (doing other things), 2015/01/07 19:39:57]

I'm missing the connection to TCMalloc.

You are removing calls to __system_property_get(), presumably because it may not
be available at some point.

You have changed the code to not compile this file for Android (in fact, you
can't compile it on Android).

Can you clarify the connection to TCMalloc, and explain why blocking compilation
of this file on Android is a good thing?

[jar (doing other things), 2015/01/07 20:28:20]

<DOH!>  I misread the file name (I stopped looking up the path after base...
src... chromium (which is about where I have the root of my tree!?!).  I now see
it was under third_party/tcmalloc.

One obvious question: If Android is not using TCMalloc, why is this even trying
to get compiled?  If it is not, why are you conditioning to preclude compilation
at this point??  Why not pull all mentions of Android?   .... and if you want it
to "sort of compile" (?) then why are you putting in a #error?

 
 #define EnvToString(envname, dflt)   \
   (!getenv(envname) ? (dflt) : getenv(envname))
 
 #define EnvToBool(envname, dflt)   \
   (!getenv(envname) ? (dflt) : memchr("tTyY1\0", getenv(envname)[0], 6) != NULL)
 
 #define EnvToInt(envname, dflt)  \
   (!getenv(envname) ? (dflt) : strtol(getenv(envname), NULL, 10))
 
 #define EnvToInt64(envname, dflt)  \
   (!getenv(envname) ? (dflt) : strtoll(getenv(envname), NULL, 10))
 
 #define EnvToDouble(envname, dflt)  \
   (!getenv(envname) ? (dflt) : strtod(getenv(envname), NULL))
 
 #endif  // defined(__ANDROID__) || defined(ANDROID)
 
 #else  // defined(ENABLE_PROFILING)
 
 #define EnvToString(envname, dflt) (dflt)
 #define EnvToBool(envname, dflt) (dflt)
 #define EnvToInt(envname, dflt) (dflt)
 #define EnvToInt64(envname, dflt) (dflt)
 #define EnvToDouble(envname, dflt) (dflt)
 
 #endif  // defined(ENABLE_PROFILING)
 
 #endif  // BASE_COMMANDLINEFLAGS_H_