Add manual methods for some ::Function signatures

Add manual methods for some ::Function signatures where the library wants function
pointers. Instead of creating function pointers to the Julia wrappers we can just look
up the pointer in the library and pass that.

Project.toml

@@ -5,4 +5,5 @@ version = "1.0.0"
 [deps]
 CEnum = "fa961155-64e5-5f13-b03f-caf6b980ea82"
 HYPRE_jll = "0a602bbd-b08b-5d75-8d32-0de6eef44785"
+Libdl = "8f399da3-3557-5675-b5ff-fb832c97cbdb"
 MPI = "da04e1cc-30fd-572f-bb4f-1f8673147195"

src/HYPRE.jl

@@ -3,6 +3,56 @@ module HYPRE
 module LibHYPRE
     include("../lib/LibHYPRE.jl")
 
+    # Add manual methods for some ::Function signatures where the library wants function
+    # pointers. Instead of creating function pointers to the Julia wrappers we can just look
+    # up the pointer in the library and pass that.
+    # TODO: Maybe this can be done automatically as post-process pass in Clang.jl
+
+    import Libdl: dlsym
+
+    function HYPRE_PCGSetPrecond(solver, precond::Function, precond_setup::Function, precond_solver)
+        precond_ptr = dlsym(HYPRE_jll.libHYPRE_handle, Symbol(precond))
+        precond_setup_ptr = dlsym(HYPRE_jll.libHYPRE_handle, Symbol(precond_setup))
+        return HYPRE_PCGSetPrecond(solver, precond_ptr, precond_setup_ptr, precond_solver)
+    end
+    function HYPRE_GMRESSetPrecond(solver, precond::Function, precond_setup::Function, precond_solver)
+        precond_ptr = dlsym(HYPRE_jll.libHYPRE_handle, Symbol(precond))
+        precond_setup_ptr = dlsym(HYPRE_jll.libHYPRE_handle, Symbol(precond_setup))
+        return HYPRE_GMRESSetPrecond(solver, precond_ptr, precond_setup_ptr, precond_solver)
+    end
+    function HYPRE_FlexGMRESSetPrecond(solver, precond::Function, precond_setup::Function, precond_solver)
+        precond_ptr = dlsym(HYPRE_jll.libHYPRE_handle, Symbol(precond))
+        precond_setup_ptr = dlsym(HYPRE_jll.libHYPRE_handle, Symbol(precond_setup))
+        return HYPRE_FlexGMRESSetPrecond(solver, precond_ptr, precond_setup_ptr, precond_solver)
+    end
+    function HYPRE_LGMRESSetPrecond(solver, precond::Function, precond_setup::Function, precond_solver)
+        precond_ptr = dlsym(HYPRE_jll.libHYPRE_handle, Symbol(precond))
+        precond_setup_ptr = dlsym(HYPRE_jll.libHYPRE_handle, Symbol(precond_setup))
+        return HYPRE_LGMRESSetPrecond(solver, precond_ptr, precond_setup_ptr, precond_solver)
+    end
+    function HYPRE_COGMRESSetPrecond(solver, precond::Function, precond_setup::Function, precond_solver)
+        precond_ptr = dlsym(HYPRE_jll.libHYPRE_handle, Symbol(precond))
+        precond_setup_ptr = dlsym(HYPRE_jll.libHYPRE_handle, Symbol(precond_setup))
+        return HYPRE_COGMRESSetPrecond(solver, precond_ptr, precond_setup_ptr, precond_solver)
+    end
+    function HYPRE_BiCGSTABSetPrecond(solver, precond::Function, precond_setup::Function, precond_solver)
+        precond_ptr = dlsym(HYPRE_jll.libHYPRE_handle, Symbol(precond))
+        precond_setup_ptr = dlsym(HYPRE_jll.libHYPRE_handle, Symbol(precond_setup))
+        return HYPRE_BiCGSTABSetPrecond(solver, precond_ptr, precond_setup_ptr, precond_solver)
+    end
+    function HYPRE_CGNRSetPrecond(solver, precond::Function, precondT::Function, precond_setup::Function, precond_solver)
+        precond_ptr = dlsym(HYPRE_jll.libHYPRE_handle, Symbol(precond))
+        precondT_ptr = dlsym(HYPRE_jll.libHYPRE_handle, Symbol(precondT))
+        precond_setup_ptr = dlsym(HYPRE_jll.libHYPRE_handle, Symbol(precond_setup))
+        return HYPRE_CGNRSetPrecond(solver, precond_ptr, precondT_ptr, precond_setup_ptr, precond_solver)
+    end
+    function HYPRE_LOBPCGSetPrecond(solver, precond::Function, precond_setup::Function, precond_solver)
+        precond_ptr = dlsym(HYPRE_jll.libHYPRE_handle, Symbol(precond))
+        precond_setup_ptr = dlsym(HYPRE_jll.libHYPRE_handle, Symbol(precond_setup))
+        return HYPRE_LOBPCGSetPrecond(solver, precond_ptr, precond_setup_ptr, precond_solver)
+    end
+
+
     # Export everything with HYPRE_ prefix
     for name in names(@__MODULE__; all=true)
         if startswith(string(name), "HYPRE_")