From 174aa2860dfbbfbfe606e563a17a2288436e4f52 Mon Sep 17 00:00:00 2001
From: Wolfgang Bangerth <bangerth@colostate.edu>
Date: Tue, 25 May 2021 10:43:52 -0600
Subject: [PATCH] Unify internal names of SUNDIALS IDA interfaces.

As previously done for the KINSOL interfaces, this patch avoids the t_dae_ prefix
and instead uses _callback as suffix. I don't quite know where the t_ prefix
comes from, but it sounds like jargon that may be present in the SUNDIALS
internal documentation but that a typical reader of our code would not
know about.

Since these are all internal functions of deal.II, we can rename them freely.
In particular, because they are in anonymous namespaces, we can re-use the same
names already in use in the KINSOL interfaces.
---
 source/sundials/ida.cc | 61 +++++++++++++++++++++---------------------
 1 file changed, 31 insertions(+), 30 deletions(-)

diff --git a/source/sundials/ida.cc b/source/sundials/ida.cc
index d03a402876..d78db1dfee 100644
--- a/source/sundials/ida.cc
+++ b/source/sundials/ida.cc
@@ -60,11 +60,11 @@ namespace SUNDIALS
   {
     template <typename VectorType>
     int
-    t_dae_residual(realtype tt,
-                   N_Vector yy,
-                   N_Vector yp,
-                   N_Vector rr,
-                   void *   user_data)
+    residual_callback(realtype tt,
+                      N_Vector yy,
+                      N_Vector yp,
+                      N_Vector rr,
+                      void *   user_data)
     {
       IDA<VectorType> &solver = *static_cast<IDA<VectorType> *>(user_data);
 
@@ -112,12 +112,12 @@ namespace SUNDIALS
 
     template <typename VectorType>
     int
-    t_dae_solve(IDAMem   IDA_mem,
-                N_Vector b,
-                N_Vector weight,
-                N_Vector yy,
-                N_Vector yp,
-                N_Vector resp)
+    solve_with_jacobian_callback(IDAMem   IDA_mem,
+                                 N_Vector b,
+                                 N_Vector weight,
+                                 N_Vector yy,
+                                 N_Vector yp,
+                                 N_Vector resp)
     {
       (void)weight;
       (void)yy;
@@ -143,16 +143,16 @@ namespace SUNDIALS
 #  else
     template <typename VectorType>
     int
-    t_dae_jacobian_setup(realtype tt,
-                         realtype cj,
-                         N_Vector yy,
-                         N_Vector yp,
-                         N_Vector /* residual */,
-                         SUNMatrix /* ignored */,
-                         void *user_data,
-                         N_Vector /* tmp1 */,
-                         N_Vector /* tmp2 */,
-                         N_Vector /* tmp3 */)
+    setup_jacobian_callback(realtype tt,
+                            realtype cj,
+                            N_Vector yy,
+                            N_Vector yp,
+                            N_Vector /* residual */,
+                            SUNMatrix /* ignored */,
+                            void *user_data,
+                            N_Vector /* tmp1 */,
+                            N_Vector /* tmp2 */,
+                            N_Vector /* tmp3 */)
     {
       Assert(user_data != nullptr, ExcInternalError());
       IDA<VectorType> &solver = *static_cast<IDA<VectorType> *>(user_data);
@@ -169,11 +169,11 @@ namespace SUNDIALS
 
     template <typename VectorType>
     int
-    t_dae_solve_jacobian_system(SUNLinearSolver LS,
-                                SUNMatrix /*ignored*/,
-                                N_Vector x,
-                                N_Vector b,
-                                realtype tol)
+    solve_with_jacobian_callback(SUNLinearSolver LS,
+                                 SUNMatrix /*ignored*/,
+                                 N_Vector x,
+                                 N_Vector b,
+                                 realtype tol)
     {
       IDA<VectorType> &solver = *static_cast<IDA<VectorType> *>(LS->content);
 
@@ -290,7 +290,8 @@ namespace SUNDIALS
     auto yy = internal::make_nvector_view(solution);
     auto yp = internal::make_nvector_view(solution_dot);
 
-    status = IDAInit(ida_mem, t_dae_residual<VectorType>, current_time, yy, yp);
+    status =
+      IDAInit(ida_mem, residual_callback<VectorType>, current_time, yy, yp);
     AssertIDA(status);
     if (get_local_tolerances)
       {
@@ -346,7 +347,7 @@ namespace SUNDIALS
     IDA_mem->ida_lsetup = t_dae_lsetup<VectorType>;
 
     if (solve_jacobian_system)
-      IDA_mem->ida_lsolve = t_dae_solve<VectorType>;
+      IDA_mem->ida_lsolve = solve_with_jacobian_callback<VectorType>;
     else
       AssertThrow(false, ExcFunctionNotProvided("solve_jacobian_system"));
 #    if DEAL_II_SUNDIALS_VERSION_LT(3, 0, 0)
@@ -385,7 +386,7 @@ namespace SUNDIALS
     AssertThrow(solve_jacobian_system || solve_with_jacobian,
                 ExcFunctionNotProvided(
                   "solve_jacobian_system or solve_with_jacobian"));
-    LS->ops->solve = t_dae_solve_jacobian_system<VectorType>;
+    LS->ops->solve = solve_with_jacobian_callback<VectorType>;
 
     // When we set an iterative solver IDA requires that resid is provided. From
     // SUNDIALS docs If an iterative method computes the preconditioned initial
@@ -436,7 +437,7 @@ namespace SUNDIALS
     // Finally tell IDA about
     // it as well. The manual says that this must happen *after*
     // calling IDASetLinearSolver
-    status = IDASetJacFn(ida_mem, &t_dae_jacobian_setup<VectorType>);
+    status = IDASetJacFn(ida_mem, &setup_jacobian_callback<VectorType>);
     AssertIDA(status);
 #  endif
     status = IDASetMaxOrd(ida_mem, data.maximum_order);
-- 
2.39.5