add folly::init to libfolly for OSS build

Summary:
We use this in eden and this avoids needing to patch the homebrew recipe.

I've also made the use of the folly symbolizer specific to the facebook
internal build of folly, because it fails to compile in the Linux OSS build
too.

Reviewed By: yfeldblum

Differential Revision: D4292166

fbshipit-source-id: b69153be8ab9cc461bc7f456248e73972ba7f461

folly/Makefile.am

@@ -433,6 +433,7 @@ libfolly_la_SOURCES = \
 	IPAddressV4.cpp \
 	IPAddressV6.cpp \
 	LifoSem.cpp \
+	init/Init.cpp \
 	io/Compression.cpp \
 	io/Cursor.cpp \
 	io/IOBuf.cpp \

folly/init/Init.cpp

@@ -19,11 +19,8 @@
 #include <glog/logging.h>
 
 #include <folly/Singleton.h>
-#if !defined(__APPLE__) && !defined(_WIN32)
-#define USE_FOLLY_SYMBOLIZER 1
-#endif
 
-#ifdef USE_FOLLY_SYMBOLIZER
+#ifdef FOLLY_USE_SYMBOLIZER
 #include <folly/experimental/symbolizer/SignalHandler.h>
 #endif
 #include <folly/portability/GFlags.h>
@@ -31,7 +28,7 @@
 namespace folly {
 
 void init(int* argc, char*** argv, bool removeFlags) {
-#ifdef USE_FOLLY_SYMBOLIZER
+#ifdef FOLLY_USE_SYMBOLIZER
   // Install the handler now, to trap errors received during startup.
   // The callbacks, if any, can be installed later
   folly::symbolizer::installFatalSignalHandler();
@@ -44,7 +41,7 @@ void init(int* argc, char*** argv, bool removeFlags) {
   auto programName = argc && argv && *argc > 0 ? (*argv)[0] : "unknown";
   google::InitGoogleLogging(programName);
 
-#ifdef USE_FOLLY_SYMBOLIZER
+#ifdef FOLLY_USE_SYMBOLIZER
   // Don't use glog's DumpStackTraceAndExit; rely on our signal handler.
   google::InstallFailureFunction(abort);
 #endif
@@ -53,7 +50,7 @@ void init(int* argc, char*** argv, bool removeFlags) {
   // things now" phase.
   folly::SingletonVault::singleton()->registrationComplete();
 
-#ifdef USE_FOLLY_SYMBOLIZER
+#ifdef FOLLY_USE_SYMBOLIZER
   // Actually install the callbacks into the handler.
   folly::symbolizer::installFatalSignalCallbacks();
 #endif