From 4277e9fd3a90db389010274ab9bd200dee1e85ea Mon Sep 17 00:00:00 2001
From: Michael Schlottke-Lakemper <michael@sloede.com>
Date: Thu, 6 Jul 2023 11:32:48 +0200
Subject: [PATCH 1/2] Provide convenience methods for Fortran interface

---
 examples/simple_trixi_controller.f90 |  9 +++++---
 src/trixi.f90                        | 34 ++++++++++++++++++++++++----
 2 files changed, 35 insertions(+), 8 deletions(-)

diff --git a/examples/simple_trixi_controller.f90 b/examples/simple_trixi_controller.f90
index 604fcdf6..85b312fc 100644
--- a/examples/simple_trixi_controller.f90
+++ b/examples/simple_trixi_controller.f90
@@ -25,18 +25,21 @@ program simple_trixi_controller_f
 
   ! Initialize Trixi
   call get_command_argument(1, argument)
-  call trixi_initialize(trim(argument) // c_null_char)
+  call trixi_initialize(argument)
 
   ! Set up the Trixi simulation
   ! We get a handle to use subsequently
   call get_command_argument(2, argument)
-  handle = trixi_initialize_simulation(trim(argument) // c_null_char)
+  handle = trixi_initialize_simulation(argument)
 
   ! Get time step length
   write(*, '(a, e14.8)') "Current time step length: ", trixi_calculate_dt(handle)
 
   ! Main loop
-  do while ( trixi_is_finished(handle) == 0 )
+  do
+    ! Exit loop once simulation is completed
+    if ( trixi_is_finished(handle) ) exit
+
     call trixi_step(handle)
   end do
 
diff --git a/src/trixi.f90 b/src/trixi.f90
index 60030c91..909a36d3 100644
--- a/src/trixi.f90
+++ b/src/trixi.f90
@@ -2,14 +2,14 @@ module LibTrixi
   implicit none
 
   interface
-    subroutine trixi_initialize(project_directory) bind(c)
+    subroutine trixi_initialize_c(project_directory) bind(c, name='trixi_initialize')
       use, intrinsic :: iso_c_binding, only: c_char
-      character(kind=c_char), intent(in) :: project_directory(*)
+      character(kind=c_char), dimension(*), intent(in) :: project_directory
     end subroutine
 
-    integer(c_int) function trixi_initialize_simulation(libelixir) bind(c)
+    integer(c_int) function trixi_initialize_simulation_c(libelixir) bind(c, name='trixi_initialize_simulation')
       use, intrinsic :: iso_c_binding, only: c_char, c_int
-      character(kind=c_char), intent(in) :: libelixir(*)
+      character(kind=c_char), dimension(*), intent(in) :: libelixir
     end function
 
     real(c_double) function trixi_calculate_dt(handle) bind(c)
@@ -17,7 +17,7 @@ real(c_double) function trixi_calculate_dt(handle) bind(c)
       integer(c_int), value, intent(in) :: handle
     end function
 
-    integer(c_int) function trixi_is_finished(handle) bind(c)
+    integer(c_int) function trixi_is_finished_c(handle) bind(c, name='trixi_is_finished')
       use, intrinsic :: iso_c_binding, only: c_int
       integer(c_int), value, intent(in) :: handle
     end function
@@ -40,4 +40,28 @@ subroutine julia_eval_string(code) bind(c)
       character(kind=c_char), intent(in) :: code(*)
     end subroutine
   end interface
+
+  contains
+
+  logical function trixi_is_finished(handle)
+    use, intrinsic :: iso_c_binding, only: c_int
+    integer(c_int), intent(in) :: handle
+
+    trixi_is_finished = trixi_is_finished_c(handle) == 1
+  end function
+
+  subroutine trixi_initialize(project_directory)
+    use, intrinsic :: iso_c_binding, only: c_null_char
+    character(len=*), intent(in) :: project_directory
+
+    call trixi_initialize_c(trim(adjustl(project_directory)) // c_null_char)
+  end subroutine
+
+  integer(c_int) function trixi_initialize_simulation(libelixir)
+    use, intrinsic :: iso_c_binding, only: c_int, c_null_char
+    character(len=*), intent(in) :: libelixir
+
+    trixi_initialize_simulation = trixi_initialize_simulation_c(trim(adjustl(libelixir)) // c_null_char)
+  end function
+
 end module

From f4dcda41307edbb79a7d41c310f2be888068b4ea Mon Sep 17 00:00:00 2001
From: Michael Schlottke-Lakemper <michael@sloede.com>
Date: Thu, 6 Jul 2023 11:43:22 +0200
Subject: [PATCH 2/2] Make `julia_eval_string` more convenient as well

---
 src/trixi.f90 | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/src/trixi.f90 b/src/trixi.f90
index 909a36d3..a9506ce6 100644
--- a/src/trixi.f90
+++ b/src/trixi.f90
@@ -35,9 +35,9 @@ subroutine trixi_finalize_simulation(handle) bind(c)
     subroutine trixi_finalize() bind(c)
     end subroutine
 
-    subroutine julia_eval_string(code) bind(c)
+    subroutine julia_eval_string_c(code) bind(c, name='julia_eval_string')
       use, intrinsic :: iso_c_binding, only: c_char
-      character(kind=c_char), intent(in) :: code(*)
+      character(kind=c_char), dimension(*), intent(in) :: code
     end subroutine
   end interface
 
@@ -64,4 +64,10 @@ integer(c_int) function trixi_initialize_simulation(libelixir)
     trixi_initialize_simulation = trixi_initialize_simulation_c(trim(adjustl(libelixir)) // c_null_char)
   end function
 
+  subroutine julia_eval_string(code)
+    use, intrinsic :: iso_c_binding, only: c_null_char
+    character(len=*), intent(in) :: code
+
+    call julia_eval_string_c(trim(adjustl(code)) // c_null_char)
+  end subroutine
 end module