added if's in uninstall/install

hook.hpp

@@ -24,7 +24,7 @@ namespace hook
 	{
 	public:
 		detour(void* addr_to_hook, void* jmp_to, bool enable = true)
-			: hook_addr(addr_to_hook), detour_addr(jmp_to)
+			: hook_addr(addr_to_hook), detour_addr(jmp_to), hook_installed(false)
 		{
 			//setup hook
 			memcpy(
@@ -44,11 +44,15 @@ namespace hook
 
 		void install()
 		{
+			if (hook_installed.load())
+				return;
 			write_to_readonly(hook_addr, jmp_code, sizeof(jmp_code));
 			hook_installed.exchange(true);
 		}
 		void uninstall()
 		{
+			if (!hook_installed.load())
+				return;
 			write_to_readonly(hook_addr, org_bytes, sizeof(org_bytes));
 			hook_installed.exchange(false);
 		}
@@ -58,7 +62,7 @@ namespace hook
 		void* hook_address() { return hook_addr; }
 		void* detour_address() { return detour_addr; }
 	private:
-		std::atomic<bool> hook_installed{ false };
+		std::atomic<bool> hook_installed;
 		void *hook_addr, *detour_addr;
 
 #if _M_IX86