add last backwards-compatible version

pfc/synchro_win.h

@@ -15,7 +15,6 @@ public:
 #endif
 	}
 	inline void destroy() throw() {DeleteCriticalSection(&sec);}
-	inline bool tryEnter() throw() { return !!TryEnterCriticalSection(&sec); }
 private:
 	_critical_section_base(const _critical_section_base&);
 	void operator=(const _critical_section_base&);
@@ -32,28 +31,24 @@ public:
 
 // Regular critical section, intended for any lifetime scopes
 class critical_section : public _critical_section_base {
+private:
+	CRITICAL_SECTION sec;
 public:
 	critical_section() {create();}
 	~critical_section() {destroy();}
 };
 
-template<typename lock_t>
-class c_insync_
+class c_insync
 {
 private:
-	lock_t& m_section;
+	_critical_section_base & m_section;
 public:
-	c_insync_(lock_t * p_section) throw() : m_section(*p_section) {m_section.enter();}
-	c_insync_(lock_t & p_section) throw() : m_section(p_section) {m_section.enter();}
-	~c_insync_() throw() {m_section.leave();}
+	c_insync(_critical_section_base * p_section) throw() : m_section(*p_section) {m_section.enter();}
+	c_insync(_critical_section_base & p_section) throw() : m_section(p_section) {m_section.enter();}
+	~c_insync() throw() {m_section.leave();}
 };
 
-typedef c_insync_<_critical_section_base> c_insync;
-
-// Old typedef for backwards compat
 #define insync(X) c_insync blah____sync(X)
-// New typedef
-#define PFC_INSYNC(X) c_insync_<decltype(X)> blah____sync(X)
 
 
 namespace pfc {
@@ -61,6 +56,32 @@ namespace pfc {
 
 // Read write lock - Vista-and-newer friendly lock that allows concurrent reads from a resource that permits such
 // Warning, non-recursion proof
+#if _WIN32_WINNT < 0x600
+
+// Inefficient fallback implementation for pre Vista OSes
+class readWriteLock {
+public:
+	readWriteLock() {}
+	void enterRead() {
+		m_obj.enter();
+	}
+	void enterWrite() {
+		m_obj.enter();
+	}
+	void leaveRead() {
+		m_obj.leave();
+	}
+	void leaveWrite() {
+		m_obj.leave();
+	}
+private:
+	critical_section m_obj;
+
+	readWriteLock( const readWriteLock & ) = delete;
+	void operator=( const readWriteLock & ) = delete;
+};
+
+#else
 class readWriteLock {
 public:
 	readWriteLock() : theLock() {
@@ -85,6 +106,7 @@ private:
 
 	SRWLOCK theLock;
 };
+#endif
 
 class _readWriteLock_scope_read {
 public: