| Alexandre Julliard | d6c0f9f | 2001-01-04 22:44:55 +0000 | [diff] [blame^] | 1 | /* A few helpful macros for implementing COM objects. |
| 2 | * |
| 3 | * Copyright 2000 TransGaming Technologies Inc. |
| 4 | */ |
| 5 | |
| 6 | #include <stddef.h> |
| 7 | |
| 8 | /* Generates the name for a vtable pointer for a given interface. */ |
| 9 | /* The canonical name for a single interface is "lpVtbl". */ |
| 10 | #define ICOM_VFIELD_MULTI_NAME2(iface) ITF_##iface |
| 11 | #define ICOM_VFIELD_MULTI_NAME(iface) ICOM_VFIELD_MULTI_NAME2(iface) |
| 12 | |
| 13 | /* Declares a vtable pointer field in an implementation. */ |
| 14 | #define ICOM_VFIELD_MULTI(iface) \ |
| 15 | iface ICOM_VFIELD_MULTI_NAME(iface) |
| 16 | |
| 17 | /* Returns the offset of a vtable pointer within an implementation object. */ |
| 18 | #define ICOM_VFIELD_OFFSET(impltype, iface) \ |
| 19 | offsetof(impltype, ICOM_VFIELD_MULTI_NAME(iface)) |
| 20 | |
| 21 | /* Given an interface pointer, returns the implementation pointer. */ |
| 22 | #define ICOM_OBJECT(impltype, ifacename, ifaceptr) \ |
| 23 | (impltype*)((ifaceptr) == NULL ? NULL \ |
| 24 | : (char*)(ifaceptr) - ICOM_VFIELD_OFFSET(impltype,ifacename)) |
| 25 | |
| 26 | #define ICOM_THIS_FROM(impltype, ifacename, ifaceptr) \ |
| 27 | impltype* This = ICOM_OBJECT(impltype, ifacename, ifaceptr) |
| 28 | |
| 29 | /* Given an object and interface name, returns a pointer to that interface. */ |
| 30 | #define ICOM_INTERFACE(implobj, iface) \ |
| 31 | (&((implobj)->ICOM_VFIELD_MULTI_NAME(iface))) |
| 32 | |
| 33 | #define ICOM_INIT_INTERFACE(implobj, ifacename, vtblname) \ |
| 34 | do { \ |
| 35 | (implobj)->ICOM_VFIELD_MULTI_NAME(ifacename).lpVtbl = &(vtblname); \ |
| 36 | } while (0) |
| 37 | |
| 38 | #define COM_INTERFACE_CAST(impltype, ifnamefrom, ifnameto, ifaceptr) \ |
| 39 | ICOM_INTERFACE(ICOM_OBJECT(impltype, ifnamefrom, ifaceptr), ifnameto) |
