| /* A few helpful macros for implementing COM objects. |
| * |
| * Copyright 2000 TransGaming Technologies Inc. |
| */ |
| |
| #include <stddef.h> |
| |
| /* Generates the name for a vtable pointer for a given interface. */ |
| /* The canonical name for a single interface is "lpVtbl". */ |
| #define ICOM_VFIELD_MULTI_NAME2(iface) ITF_##iface |
| #define ICOM_VFIELD_MULTI_NAME(iface) ICOM_VFIELD_MULTI_NAME2(iface) |
| |
| /* Declares a vtable pointer field in an implementation. */ |
| #define ICOM_VFIELD_MULTI(iface) \ |
| iface ICOM_VFIELD_MULTI_NAME(iface) |
| |
| /* Returns the offset of a vtable pointer within an implementation object. */ |
| #define ICOM_VFIELD_OFFSET(impltype, iface) \ |
| offsetof(impltype, ICOM_VFIELD_MULTI_NAME(iface)) |
| |
| /* Given an interface pointer, returns the implementation pointer. */ |
| #define ICOM_OBJECT(impltype, ifacename, ifaceptr) \ |
| (impltype*)((ifaceptr) == NULL ? NULL \ |
| : (char*)(ifaceptr) - ICOM_VFIELD_OFFSET(impltype,ifacename)) |
| |
| #define ICOM_THIS_FROM(impltype, ifacename, ifaceptr) \ |
| impltype* This = ICOM_OBJECT(impltype, ifacename, ifaceptr) |
| |
| /* Given an object and interface name, returns a pointer to that interface. */ |
| #define ICOM_INTERFACE(implobj, iface) \ |
| (&((implobj)->ICOM_VFIELD_MULTI_NAME(iface))) |
| |
| #define ICOM_INIT_INTERFACE(implobj, ifacename, vtblname) \ |
| do { \ |
| (implobj)->ICOM_VFIELD_MULTI_NAME(ifacename).lpVtbl = &(vtblname); \ |
| } while (0) |
| |
| #define COM_INTERFACE_CAST(impltype, ifnamefrom, ifnameto, ifaceptr) \ |
| ICOM_INTERFACE(ICOM_OBJECT(impltype, ifnamefrom, ifaceptr), ifnameto) |
