Allow users to specify custom destroy function

doc/shared/sunstepper/SUNStepper_Description.rst

@@ -81,7 +81,9 @@ from an ARKODE integrator.
 
 .. c:function:: SUNErrCode SUNStepper_Destroy(SUNStepper *stepper)
 
-   This function destroys a :c:type:`SUNStepper` object.
+   This function frees memory allocated by the :c:type:`SUNStepper` base class
+   and uses the function pointer optionally specified with
+   :c:type:`SUNStepper_SetDestroyFn` to free the content.
 
    :param stepper: a pointer to a stepper object.
    :return: A :c:type:`SUNErrCode` indicating success or failure.
@@ -284,6 +286,17 @@ determined by the "consumer" of the :c:type:`SUNStepper`.
    :return: A :c:type:`SUNErrCode` indicating success or failure.
 
 
+.. c:function:: SUNErrCode SUNStepper_SetDestroyFn(SUNStepper stepper, SUNStepperDestroyFn fn)
+
+   This function attaches a :c:type:`SUNStepperDestroyFn` function to a
+   :c:type:`SUNStepper`. The provided function is responsible for freeing any
+   memory allocated for the :c:type:`SUNStepper` content.
+
+   :param stepper: a stepper object.
+   :param fn: the :c:type:`SUNStepperDestroyFn` function to attach.
+   :return: A :c:type:`SUNErrCode` indicating success or failure.
+
+
 .. _SUNStepper.Description.ImplMethods:
 
 Implementation Specific Methods
@@ -322,3 +335,9 @@ abstract base class.
    This type represents a function with the signature of
    :c:func:`SUNStepper_SetForcing`.
 
+
+.. c:type:: SUNErrCode (*SUNStepperDestroyFn)(SUNStepper stepper)
+
+   This type represents a function with the signature similar to
+   :c:func:`SUNStepper_Destroy` for freeing the content associated with a
+   :c:type:`SUNStepper`.

include/sundials/sundials_stepper.h

@@ -45,6 +45,8 @@ typedef SUNErrCode (*SUNStepperSetForcingFn)(SUNStepper stepper,
                                              sunrealtype tscale,
                                              N_Vector* forcing, int nforcing);
 
+typedef SUNErrCode (*SUNStepperDestroyFn)(SUNStepper stepper);
+
 SUNDIALS_EXPORT
 SUNErrCode SUNStepper_Create(SUNContext sunctx, SUNStepper* stepper);
 
@@ -98,6 +100,9 @@ SUNErrCode SUNStepper_SetStopTimeFn(SUNStepper stepper,
 SUNDIALS_EXPORT SUNErrCode SUNStepper_SetForcingFn(SUNStepper stepper,
                                                    SUNStepperSetForcingFn fn);
 
+SUNDIALS_EXPORT SUNErrCode SUNStepper_SetDestroyFn(SUNStepper stepper,
+                                                   SUNStepperDestroyFn fn);
+
 #ifdef __cplusplus
 }
 #endif

src/sundials/fmod_int32/fsundials_core_mod.c

@@ -2882,4 +2882,18 @@ SWIGEXPORT int _wrap_FSUNStepper_SetForcingFn(void *farg1, SUNStepperSetForcingF
 }
 
 
+SWIGEXPORT int _wrap_FSUNStepper_SetDestroyFn(void *farg1, SUNStepperDestroyFn farg2) {
+  int fresult ;
+  SUNStepper arg1 = (SUNStepper) 0 ;
+  SUNStepperDestroyFn arg2 = (SUNStepperDestroyFn) 0 ;
+  SUNErrCode result;
+
+  arg1 = (SUNStepper)(farg1);
+  arg2 = (SUNStepperDestroyFn)(farg2);
+  result = (SUNErrCode)SUNStepper_SetDestroyFn(arg1,arg2);
+  fresult = (SUNErrCode)(result);
+  return fresult;
+}
+
+
 

src/sundials/fmod_int32/fsundials_core_mod.f90

@@ -559,6 +559,7 @@ module fsundials_core_mod
  public :: FSUNStepper_SetResetFn
  public :: FSUNStepper_SetStopTimeFn
  public :: FSUNStepper_SetForcingFn
+ public :: FSUNStepper_SetDestroyFn
 
 ! WRAPPER DECLARATIONS
 interface
@@ -2208,6 +2209,15 @@ function swigc_FSUNStepper_SetForcingFn(farg1, farg2) &
 integer(C_INT) :: fresult
 end function
 
+function swigc_FSUNStepper_SetDestroyFn(farg1, farg2) &
+bind(C, name="_wrap_FSUNStepper_SetDestroyFn") &
+result(fresult)
+use, intrinsic :: ISO_C_BINDING
+type(C_PTR), value :: farg1
+type(C_FUNPTR), value :: farg2
+integer(C_INT) :: fresult
+end function
+
 end interface
 
 
@@ -5226,5 +5236,21 @@ function FSUNStepper_SetForcingFn(stepper, fn) &
 swig_result = fresult
 end function
 
+function FSUNStepper_SetDestroyFn(stepper, fn) &
+result(swig_result)
+use, intrinsic :: ISO_C_BINDING
+integer(C_INT) :: swig_result
+type(C_PTR) :: stepper
+type(C_FUNPTR), intent(in), value :: fn
+integer(C_INT) :: fresult 
+type(C_PTR) :: farg1 
+type(C_FUNPTR) :: farg2 
+
+farg1 = stepper
+farg2 = fn
+fresult = swigc_FSUNStepper_SetDestroyFn(farg1, farg2)
+swig_result = fresult
+end function
+
 
 end module

src/sundials/fmod_int64/fsundials_core_mod.c

@@ -2882,4 +2882,18 @@ SWIGEXPORT int _wrap_FSUNStepper_SetForcingFn(void *farg1, SUNStepperSetForcingF
 }
 
 
+SWIGEXPORT int _wrap_FSUNStepper_SetDestroyFn(void *farg1, SUNStepperDestroyFn farg2) {
+  int fresult ;
+  SUNStepper arg1 = (SUNStepper) 0 ;
+  SUNStepperDestroyFn arg2 = (SUNStepperDestroyFn) 0 ;
+  SUNErrCode result;
+
+  arg1 = (SUNStepper)(farg1);
+  arg2 = (SUNStepperDestroyFn)(farg2);
+  result = (SUNErrCode)SUNStepper_SetDestroyFn(arg1,arg2);
+  fresult = (SUNErrCode)(result);
+  return fresult;
+}
+
+
 

src/sundials/fmod_int64/fsundials_core_mod.f90

@@ -559,6 +559,7 @@ module fsundials_core_mod
  public :: FSUNStepper_SetResetFn
  public :: FSUNStepper_SetStopTimeFn
  public :: FSUNStepper_SetForcingFn
+ public :: FSUNStepper_SetDestroyFn
 
 ! WRAPPER DECLARATIONS
 interface
@@ -2208,6 +2209,15 @@ function swigc_FSUNStepper_SetForcingFn(farg1, farg2) &
 integer(C_INT) :: fresult
 end function
 
+function swigc_FSUNStepper_SetDestroyFn(farg1, farg2) &
+bind(C, name="_wrap_FSUNStepper_SetDestroyFn") &
+result(fresult)
+use, intrinsic :: ISO_C_BINDING
+type(C_PTR), value :: farg1
+type(C_FUNPTR), value :: farg2
+integer(C_INT) :: fresult
+end function
+
 end interface
 
 
@@ -5226,5 +5236,21 @@ function FSUNStepper_SetForcingFn(stepper, fn) &
 swig_result = fresult
 end function
 
+function FSUNStepper_SetDestroyFn(stepper, fn) &
+result(swig_result)
+use, intrinsic :: ISO_C_BINDING
+integer(C_INT) :: swig_result
+type(C_PTR) :: stepper
+type(C_FUNPTR), intent(in), value :: fn
+integer(C_INT) :: fresult 
+type(C_PTR) :: farg1 
+type(C_FUNPTR) :: farg2 
+
+farg1 = stepper
+farg2 = fn
+fresult = swigc_FSUNStepper_SetDestroyFn(farg1, farg2)
+swig_result = fresult
+end function
+
 
 end module

src/sundials/sundials_stepper.c

@@ -50,7 +50,9 @@ SUNErrCode SUNStepper_Destroy(SUNStepper* stepper_ptr)
 {
   if (stepper_ptr != NULL)
   {
-    free((*stepper_ptr)->ops);
+    const SUNStepper_Ops ops = (*stepper_ptr)->ops;
+    if (ops && ops->destroy) { ops->destroy(*stepper_ptr); }
+    free(ops);
     free(*stepper_ptr);
     *stepper_ptr = NULL;
   }

src/sundials/sundials_stepper_impl.h

@@ -20,16 +20,15 @@
 extern "C" {
 #endif
 
-typedef struct SUNStepper_Ops_* SUNStepper_Ops;
-
-struct SUNStepper_Ops_
+typedef struct
 {
   SUNStepperEvolveFn evolve;
   SUNStepperFullRhsFn fullrhs;
   SUNStepperResetFn reset;
   SUNStepperSetStopTimeFn setstoptime;
   SUNStepperSetForcingFn setforcing;
-};
+  SUNStepperDestroyFn destroy;
+}* SUNStepper_Ops;
 
 struct SUNStepper_
 {