Use _CFIsMainThread as a shim for pthread_main_np on Linux

Author: seabaylea

CoreFoundation/Base.subproj/CFBase.h

@@ -623,6 +623,11 @@ CFIndex CFAllocatorGetPreferredSizeForSize(CFAllocatorRef allocator, CFIndex siz
 CF_EXPORT
 void CFAllocatorGetContext(CFAllocatorRef allocator, CFAllocatorContext *context);
 
+#if DEPLOYMENT_TARGET_LINUX
+CF_EXPORT
+int _CFIsMainThread(void);
+#endif
+
 
 /* Polymorphic CF functions */
 

CoreFoundation/Base.subproj/CFInternal.h

@@ -806,7 +806,7 @@ CF_EXPORT void _NS_pthread_setname_np(const char *name);
 #endif
 
 #if DEPLOYMENT_TARGET_LINUX
-CF_EXPORT Boolean _CFIsMainThread(void);
+CF_EXPORT int _CFIsMainThread(void);
 #define pthread_main_np _CFIsMainThread
 #endif
 

CoreFoundation/Base.subproj/CFPlatform.c

@@ -159,7 +159,7 @@ const char *_CFProcessPath(void) {
 #include <unistd.h>
 #include <syscall.h>
 
-Boolean _CFIsMainThread(void) {
+int _CFIsMainThread(void) {
     return syscall(SYS_gettid) == getpid();
 }
 

Foundation/NSOperation.swift

@@ -9,6 +9,12 @@
 
 #if DEPLOYMENT_ENABLE_LIBDISPATCH
 import Dispatch
+#if os(Linux)
+import CoreFoundation
+private func pthread_main_np() -> Int32 {
+    return _CFIsMainThread()
+}
+#endif
 #endif
 
 public class NSOperation : NSObject {