Fix example for changes to function pointer interface

Author: sethrj

Examples/fortran/funcptr/example.c

@@ -1,19 +1,19 @@
 /* File : example.c */
 
-int do_op(int a, int b, int (*op)(int,int)) {
-  return (*op)(a,b);
+int do_op(int a, int b, int (*op)(int, int)) {
+  return (*op)(a, b);
 }
 
 int add(int a, int b) {
-  return a+b;
+  return a + b;
 }
 
 int sub(int a, int b) {
-  return a-b;
+  return a - b;
 }
 
 int mul(int a, int b) {
-  return a*b;
+  return a * b;
 }
 
-int (*funcvar)(int,int) = add;
+int (*funcvar)(int, int) = add;

Examples/fortran/funcptr/example.h

@@ -1,9 +1,11 @@
 /* file: example.h */
 
-extern int do_op(int,int, int (*op)(int,int));
-extern int add(int,int);
-extern int sub(int,int);
-extern int mul(int,int);
+typedef int (*binary_func)(int, int);
 
-extern int (*funcvar)(int,int);
+extern int do_op(int, int, binary_func);
+extern int add(int, int);
+extern int sub(int, int);
+extern int mul(int, int);
+
+extern int (*funcvar)(int, int);
 

Examples/fortran/funcptr/example.i

@@ -4,8 +4,14 @@
 #include "example.h"
 %}
 
+%fortrancallback("%s") binary_op;
+int binary_op(int a, int b);
+
+/* Function pointer: f(int, int) ->  int */
+typedef int (*binary_func)(int, int);
+
 /* Wrap a function taking a pointer to a function */
-extern int  do_op(int a, int b, int (*op)(int, int));
+extern int do_op(int a, int b, binary_func op);
 
 /* Now install a bunch of "ops" as constants */
 %constant int (*ADD)(int,int) = add;

Examples/fortran/funcptr/runme.f90

@@ -4,16 +4,6 @@ module fortran_ops
   implicit none
   public
 
-  abstract interface
-    ! Interface corresponding to the C typedef "BinaryOp"
-    function binary_op(aa, bb) bind(C)  result(cc)
-      use, intrinsic :: ISO_C_BINDING
-      integer(C_INT), intent(in), value :: aa
-      integer(C_INT), intent(in), value :: bb
-      integer(C_INT) :: cc
-    end function
-  end interface
-  
 contains
   ! Fortran function that we can export so that
   ! it's available to C code
@@ -39,19 +29,16 @@ program fortran_funptr_runme
   integer, parameter :: STDOUT = OUTPUT_UNIT
   integer(C_INT) :: a = 4
   integer(C_INT) :: b = 3
-  type(C_FUNPTR) :: temp_funptr
-  procedure(binary_op), pointer :: my_ffunc => null()
+  procedure(binary_op), pointer :: fptr => null()
 
-  write(STDOUT,*) "SWIG-wrapped C function pointer:", do_op(a,b,add)
-  write(STDOUT,*) "SWIG-wrapped C function pointer:", do_op(a,b,sub)
-  write(STDOUT,*) "SWIG-wrapped C function pointer:", do_op(a,b,mul)
+  call c_f_procpointer(add, fptr)
+  write(STDOUT,*) "SWIG-wrapped C function pointer:", do_op(a, b, fptr)
+  call c_f_procpointer(sub, fptr)                                 
+  write(STDOUT,*) "SWIG-wrapped C function pointer:", do_op(a, b, fptr)
+  call c_f_procpointer(mul, fptr)                                 
+  write(STDOUT,*) "SWIG-wrapped C function pointer:", do_op(a, b, fptr)
 
   ! Convert Fortran function to C function pointer
-  temp_funptr = c_funloc(fortran_mul)
-  write(STDOUT,*) "C call to Fortran function:", do_op(a,b,temp_funptr)
-
-  ! Convert C function pointer to a Fortran function pointer
-  call c_f_procpointer(add, my_ffunc)
-  write(STDOUT,*) "Fortran direct call to C function:", my_ffunc(a,b)
+  write(STDOUT,*) "C call to Fortran function:", do_op(a, b, fortran_mul)
 
 end program