michael@0: 
michael@0: #include <stdio.h>
michael@0: 
michael@0: typedef unsigned nsresult;
michael@0: typedef unsigned uint32_t;
michael@0: typedef unsigned nsXPCVariant;
michael@0: 
michael@0: 
michael@0: #if defined(WIN32)
michael@0: #define NS_IMETHOD virtual nsresult __stdcall
michael@0: #define NS_IMETHODIMP nsresult __stdcall
michael@0: #else
michael@0: #define NS_IMETHOD virtual nsresult
michael@0: #define NS_IMETHODIMP nsresult
michael@0: #endif
michael@0: 
michael@0: 
michael@0: class base{
michael@0: public:
michael@0:   NS_IMETHOD ignored() = 0;
michael@0: };
michael@0: 
michael@0: class foo : public base {
michael@0: public:
michael@0:   NS_IMETHOD callme1(int i, int j) = 0;
michael@0:   NS_IMETHOD callme2(int i, int j) = 0;
michael@0:   NS_IMETHOD callme3(int i, int j) = 0;
michael@0: };
michael@0: 
michael@0: class bar : public foo{
michael@0: public:
michael@0:   NS_IMETHOD ignored();
michael@0:   NS_IMETHOD callme1(int i, int j);
michael@0:   NS_IMETHOD callme2(int i, int j);
michael@0:   NS_IMETHOD callme3(int i, int j);
michael@0: };
michael@0: 
michael@0: class baz : public base {
michael@0: public:
michael@0:   NS_IMETHOD ignored();
michael@0:   NS_IMETHOD callme1();
michael@0:   NS_IMETHOD callme2();
michael@0:   NS_IMETHOD callme3();
michael@0:   void setfoo(foo* f) {other = f;}
michael@0: 
michael@0:   foo* other;
michael@0: };
michael@0: NS_IMETHODIMP baz::ignored(){return 0;}
michael@0: 
michael@0: NS_IMETHODIMP bar::ignored(){return 0;}
michael@0: 
michael@0: NS_IMETHODIMP bar::callme1(int i, int j)
michael@0: {
michael@0:   printf("called bar::callme1 with: %d %d\n", i, j);
michael@0:   return 15;
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP bar::callme2(int i, int j)
michael@0: {
michael@0:   printf("called bar::callme2 with: %d %d\n", i, j);
michael@0:   return 25;
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP bar::callme3(int i, int j)
michael@0: {
michael@0:   printf("called bar::callme3 with: %d %d\n", i, j);
michael@0:   return 35;
michael@0: }
michael@0: 
michael@0: void docall(foo* f, int i, int j){
michael@0:   f->callme1(i, j); 
michael@0: }
michael@0: 
michael@0: /***************************************************************************/
michael@0: #if defined(WIN32)
michael@0: 
michael@0: static int __stdcall
michael@0: PrepareAndDispatch(baz* self, uint32_t methodIndex,
michael@0:                    uint32_t* args, uint32_t* stackBytesToPop)
michael@0: {
michael@0:     fprintf(stdout, "PrepareAndDispatch (%p, %d, %p)\n",
michael@0:         (void*)self, methodIndex, (void*)args);
michael@0:     foo* a = self->other;
michael@0:     int p1 = (int) *args;
michael@0:     int p2 = (int) *(args+1);
michael@0:     int out = 0;
michael@0:     switch(methodIndex)
michael@0:     {
michael@0:     case 1: out = a->callme1(p1, p2); break;
michael@0:     case 2: out = a->callme2(p1, p2); break;
michael@0:     case 3: out = a->callme3(p1, p2); break;
michael@0:     }
michael@0:     *stackBytesToPop = 2*4;
michael@0:     return out;
michael@0: }
michael@0: 
michael@0: #ifndef __GNUC__
michael@0: static __declspec(naked) void SharedStub(void)
michael@0: {
michael@0:     __asm {
michael@0:         push ebp            // set up simple stack frame
michael@0:         mov  ebp, esp       // stack has: ebp/vtbl_index/retaddr/this/args
michael@0:         push ecx            // make room for a ptr
michael@0:         lea  eax, [ebp-4]   // pointer to stackBytesToPop
michael@0:         push eax
michael@0:         lea  ecx, [ebp+16]  // pointer to args
michael@0:         push ecx
michael@0:         mov  edx, [ebp+4]   // vtbl_index
michael@0:         push edx
michael@0:         mov  eax, [ebp+12]  // this
michael@0:         push eax
michael@0:         call PrepareAndDispatch
michael@0:         mov  edx, [ebp+8]   // return address
michael@0:         mov  ecx, [ebp-4]   // stackBytesToPop
michael@0:         add  ecx, 12        // for this, the index, and ret address
michael@0:         mov  esp, ebp
michael@0:         pop  ebp
michael@0:         add  esp, ecx       // fix up stack pointer
michael@0:         jmp  edx            // simulate __stdcall return
michael@0:     }
michael@0: }
michael@0: 
michael@0: // these macros get expanded (many times) in the file #included below
michael@0: #define STUB_ENTRY(n) \
michael@0: __declspec(naked) nsresult __stdcall baz::callme##n() \
michael@0: { __asm push n __asm jmp SharedStub }
michael@0: 
michael@0: #else /* __GNUC__ */
michael@0: 
michael@0: #define STUB_ENTRY(n) \
michael@0: nsresult __stdcall baz::callme##n() \
michael@0: { \
michael@0:   uint32_t *args, stackBytesToPop; \
michael@0:   int result = 0; \
michael@0:   baz *obj; \
michael@0:   __asm__ __volatile__ ( \
michael@0:     "leal   0x0c(%%ebp), %0\n\t"    /* args */ \
michael@0:     "movl   0x08(%%ebp), %1\n\t"    /* this */ \
michael@0:     : "=r" (args), \
michael@0:       "=r" (obj)); \
michael@0:   result = PrepareAndDispatch(obj, n, args,&stackBytesToPop); \
michael@0:     fprintf(stdout, "stub returning: %d\n", result); \
michael@0:     fprintf(stdout, "bytes to pop:  %d\n", stackBytesToPop); \
michael@0:     return result; \
michael@0: }
michael@0: 
michael@0: #endif /* ! __GNUC__ */
michael@0: 
michael@0: #else
michael@0: /***************************************************************************/
michael@0: // just Linux_x86 now. Add other later...
michael@0: 
michael@0: static int
michael@0: PrepareAndDispatch(baz* self, uint32_t methodIndex, uint32_t* args)
michael@0: {
michael@0:     foo* a = self->other;
michael@0:     int p1 = (int) *args;
michael@0:     int p2 = (int) *(args+1);
michael@0:     switch(methodIndex)
michael@0:     {
michael@0:     case 1: a->callme1(p1, p2); break;
michael@0:     case 2: a->callme2(p1, p2); break;
michael@0:     case 3: a->callme3(p1, p2); break;
michael@0:     }
michael@0:     return 1;
michael@0: }
michael@0: 
michael@0: #define STUB_ENTRY(n) \
michael@0: nsresult baz::callme##n() \
michael@0: { \
michael@0:   void* method = PrepareAndDispatch; \
michael@0:   nsresult result; \
michael@0:   __asm__ __volatile__( \
michael@0:     "leal   0x0c(%%ebp), %%ecx\n\t"    /* args */ \
michael@0:     "pushl  %%ecx\n\t" \
michael@0:     "pushl  $"#n"\n\t"                 /* method index */ \
michael@0:     "movl   0x08(%%ebp), %%ecx\n\t"    /* this */ \
michael@0:     "pushl  %%ecx\n\t" \
michael@0:     "call   *%%edx"                    /* PrepareAndDispatch */ \
michael@0:     : "=a" (result)     /* %0 */ \
michael@0:     : "d" (method)      /* %1 */ \
michael@0:     : "memory" ); \
michael@0:     return result; \
michael@0: }
michael@0: 
michael@0: #endif
michael@0: /***************************************************************************/
michael@0: 
michael@0: STUB_ENTRY(1)
michael@0: STUB_ENTRY(2)
michael@0: STUB_ENTRY(3)
michael@0: 
michael@0: int main()
michael@0: {
michael@0:   foo* a = new bar();
michael@0:   baz* b = new baz();
michael@0: 
michael@0:   /* here we make the global 'check for alloc failure' checker happy */
michael@0:   if(!a || !b)
michael@0:     return 1;
michael@0:   
michael@0:   foo* c = (foo*)b;
michael@0: 
michael@0:   b->setfoo(a);
michael@0:   c->callme1(1,2);
michael@0:   c->callme2(2,4);
michael@0:   c->callme3(3,6);
michael@0: 
michael@0:   return 0;
michael@0: }