add struct fortran => C,Cxx

Author: scivision

src/CMakeLists.txt

@@ -5,16 +5,24 @@ add_subdirectory(cxx)
 add_subdirectory(fortran)
 
 # -- Fortran calling C++
-add_executable(fortran_call_cxx fortran/math_main.f90)
-target_link_libraries(fortran_call_cxx PRIVATE math_cxx)
+add_executable(fortran_cxx_math fortran/math_main.f90)
+target_link_libraries(fortran_cxx_math PRIVATE math_cxx)
 # LINKER_LANGUAGE option is necessary for ifort at least
-set_target_properties(fortran_call_cxx PROPERTIES LINKER_LANGUAGE Fortran)
-add_test(NAME Fortran_call_C++ COMMAND fortran_call_cxx)
+set_target_properties(fortran_cxx_math PROPERTIES LINKER_LANGUAGE Fortran)
+add_test(NAME Fortran_C++_math COMMAND fortran_cxx_math)
+
+add_executable(fortran_cxx_struct fortran/struct_main.f90)
+target_link_libraries(fortran_cxx_struct PRIVATE struct_cxx)
+add_test(NAME Fortran_C++_struct COMMAND fortran_cxx_struct)
 
 # -- Fortran calling C
-add_executable(fortran_call_c fortran/math_main.f90)
-target_link_libraries(fortran_call_c PRIVATE math_c)
-add_test(NAME Fortran_call_C COMMAND fortran_call_c)
+add_executable(fortran_c_math fortran/math_main.f90)
+target_link_libraries(fortran_c_math PRIVATE math_c)
+add_test(NAME Fortran_C_math COMMAND fortran_c_math)
+
+add_executable(fortran_c_struct fortran/struct_main.f90)
+target_link_libraries(fortran_c_struct PRIVATE struct_c)
+add_test(NAME Fortran_C_struct COMMAND fortran_c_struct)
 
 # -- C calling Fortran
 add_executable(c_fortran_error c/error_main.c)
@@ -49,6 +57,6 @@ set_target_properties(cxx_fortran_struct PROPERTIES LINKER_LANGUAGE CXX)
 add_test(NAME C++_Fortran_struct COMMAND $<TARGET_FILE:cxx_fortran_struct>)
 
 # -- test wrapup
-set_tests_properties(C++_Fortran_math C++_Fortran_error Fortran_call_C Fortran_call_C++ PROPERTIES
+set_tests_properties(C++_Fortran_math C++_Fortran_error Fortran_C_math Fortran_C++_math PROPERTIES
 TIMEOUT 5
 )

src/c/CMakeLists.txt

@@ -1 +1,3 @@
 add_library(math_c OBJECT math_lib.c)
+
+add_library(struct_c OBJECT struct_lib.c)

src/c/meson.build

@@ -1 +1,3 @@
 math_c = library('math_c', 'math_lib.c')
+
+struct_c = library('struct_c', 'struct_lib.c')

src/c/struct_lib.c

@@ -0,0 +1,33 @@
+#include <stdbool.h>
+#include <string.h>
+#include <stdlib.h>
+#include <stdio.h>
+
+struct params {
+  // order and lengths must match in Fortran and C
+  int my_int;
+  bool my_bool;
+  int Lmy_char;
+  char my_char[1000];
+};
+
+void struct_check(struct params);
+
+void struct_check(struct params s) {
+
+if (s.my_int != 123) {
+  fprintf(stderr, "Error: my_int = %d\n", s.my_int);
+  exit(EXIT_FAILURE);
+}
+
+if (! s.my_bool) {
+  fprintf(stderr, "Error: my_bool is false\n");
+  exit(EXIT_FAILURE);
+}
+
+if (s.Lmy_char != 5) {
+  fprintf(stderr, "Error: my_char wrong length %d\n", s.Lmy_char);
+  exit(EXIT_FAILURE);
+}
+
+}

src/cxx/CMakeLists.txt

@@ -1 +1,3 @@
 add_library(math_cxx OBJECT math_lib.cxx)
+
+add_library(struct_cxx OBJECT struct_lib.cxx)

src/cxx/math_main.cxx

@@ -15,7 +15,7 @@ int main()
 
   for (auto i=0u; i < x2.size(); i++){
     if (x2[i] != 2*x[i]){
-      fprintf(stderr, "value %d != %d", x2[i], x[i]);
+      std::cerr << "value " <<  x2[i] << "!=" << x[i] << std::endl;
       return EXIT_FAILURE;
     }
   }

src/cxx/meson.build

@@ -1 +1,3 @@
 math_cxx = library('math_cxx', 'math_lib.cxx')
+
+struct_cxx = library('struct_cxx', 'struct_lib.cxx')

src/cxx/struct_lib.cxx

@@ -0,0 +1,32 @@
+#include <iostream>
+#include <cstring>
+#include <cstdlib>
+
+struct params {
+  // order and lengths must match in Fortran and C
+  int my_int;
+  bool my_bool;
+  int Lmy_char;
+  char my_char[1000];
+};
+
+void struct_check(struct params);
+
+void struct_check(struct params s) {
+
+if (s.my_int != 123) {
+  std::cerr << "Error: my_int = " << s.my_int << std::endl;
+  exit(EXIT_FAILURE);
+}
+
+if (! s.my_bool) {
+  std::cerr << "Error: my_bool is false" << std::endl;
+  exit(EXIT_FAILURE);
+}
+
+if (s.Lmy_char != 5) {
+  std::cerr << "Error: my_char wrong length " << s.Lmy_char << std::endl;
+  exit(EXIT_FAILURE);
+}
+
+}

src/fortran/struct_main.f90

@@ -0,0 +1,46 @@
+program struct_tx
+
+use, intrinsic :: iso_c_binding, only : c_int, c_bool, c_char, c_null_char
+
+implicit none (type, external)
+
+
+type, bind(C) :: my_struct
+!! order and length must match in Fortran and C
+integer(c_int) :: my_int
+logical(c_bool) :: my_bool
+integer(c_int) :: Lmy_char
+character(kind=c_char) :: my_char(1000)
+!! character(kind=c_char) in bind(c) type cannot be allocatable. Just have to make it "long enough"
+!! or use iso_c_binding.h stuff
+
+end type my_struct
+
+
+interface
+subroutine struct_check(p) bind(C)
+import my_struct
+type(my_struct), intent(in) :: p
+end subroutine struct_check
+end interface
+
+
+type(my_struct) :: s
+integer :: i
+character(:), allocatable :: my_char
+
+my_char = "Hello"
+
+
+s%my_int = 123
+s%my_bool = .true.
+s%Lmy_char = len(my_char)
+
+do i = 1, s%Lmy_char
+  s%my_char(i) = my_char(i:i)
+end do
+s%my_char(i+1) = c_null_char
+
+
+print *, "OK: Fortran => C struct"
+end program

src/meson.build

@@ -5,20 +5,27 @@ subdir('cxx')
 subdir('fortran')
 
 # -- Fortran calling C++
-fortran_call_cxx = executable('fortran_call_cxx',
+fortran_cxx_math = executable('fortran_call_cxx',
   sources: files('fortran/math_main.f90'),
   link_with: math_cxx,
   link_language: 'fortran'
 )
-test('Fortran call C++', fortran_call_cxx, timeout: 5)
+test('Fortran C++ math', fortran_cxx_math, timeout: 5)
 
 # -- Fortran calling C
-fortran_call_c = executable('fortran_call_c',
+fortran_c_math = executable('fortran_c_math',
   sources: files('fortran/math_main.f90'),
   link_with: math_c,
   link_language: 'fortran'
 )
-test('Fortran call C', fortran_call_c,  timeout: 5)
+test('Fortran C math', fortran_c_math,  timeout: 5)
+
+fortran_c_struct = executable('fortran_call_c',
+  sources: files('fortran/struct_main.f90'),
+  link_with: struct_c,
+  link_language: 'fortran'
+)
+test('Fortran C struct', fortran_c_struct,  timeout: 5)
 
 # -- C calling Fortran
 c_fortran_error = executable('c_fortran_error',