Add recognition of the SQLITE_OS_WINRT compile-time option.

Use InitializeCriticalSectionEx() under winRT.

FossilOrigin-Name: 8b7ca8a09f7b69db1fe766616cba0307e681a6f3

src/mutex_w32.c

@@ -114,7 +114,11 @@ static int winMutexInit(void){
   if( InterlockedCompareExchange(&winMutex_lock, 1, 0)==0 ){
     int i;
     for(i=0; i<ArraySize(winMutex_staticMutexes); i++){
+#if SQLITE_OS_WINRT
+      InitializeCriticalSectionEx(&winMutex_staticMutexes[i].mutex, 0, 0);
+#else
       InitializeCriticalSection(&winMutex_staticMutexes[i].mutex);
+#endif
     }
     winMutex_isInit = 1;
   }else{

src/os.h

@@ -115,6 +115,14 @@
 # define SQLITE_OS_WINCE 0
 #endif
 
+/*
+** Determine if we are dealing with WindowsRT (Metro) as this has a different and
+** incompatible API from win32.
+*/
+#if !defined(SQLITE_OS_WINRT)
+# define SQLITE_OS_WINRT 0
+#endif
+
 /* If the SET_FULLSYNC macro is not defined above, then make it
 ** a no-op
 */