Support read/write to structs originating in C

integration_tests/CMakeLists.txt

@@ -369,6 +369,8 @@ RUN(NAME structs_16          LABELS cpython llvm c)
 RUN(NAME structs_17          LABELS cpython llvm c)
 RUN(NAME structs_18          LABELS llvm c
     EXTRAFILES structs_18b.c)
+RUN(NAME structs_19          LABELS cpython llvm c
+    EXTRAFILES structs_19b.c)
 RUN(NAME sizeof_01           LABELS llvm c
         EXTRAFILES sizeof_01b.c)
 RUN(NAME enum_01             LABELS cpython llvm c)

integration_tests/structs_19.py

@@ -0,0 +1,70 @@
+from ltypes import (i8, dataclass, i32, f32, c32, f64, i16, i64, c64,
+    ccall, CPtr, c_p_pointer, Pointer)
+
+@dataclass
+class buffer_struct:
+    buffer8: i8
+    buffer1: i32
+    buffer2: f32
+    buffer3: c32
+    buffer4: f64
+    buffer5: i16
+    buffer6: i64
+    buffer7: c64
+
+@ccall
+def get_buffer() -> CPtr:
+    pass
+
+@ccall
+def fill_buffer(buffer_cptr: CPtr):
+    pass
+
+def f():
+    b: CPtr = get_buffer()
+    pb: Pointer[buffer_struct] = c_p_pointer(b, buffer_struct)
+    pb.buffer8 = i8(3)
+    pb.buffer1 = i32(4)
+    pb.buffer2 = f32(5)
+    pb.buffer3 = c32(9)
+    pb.buffer4 = f64(6)
+    pb.buffer5 = i16(7)
+    pb.buffer6 = i64(8)
+    pb.buffer7 = c64(10)
+    print(pb.buffer8)
+    print(pb.buffer1)
+    print(pb.buffer2)
+    print(pb.buffer3)
+    print(pb.buffer4)
+    print(pb.buffer5)
+    print(pb.buffer6)
+    print(pb.buffer7)
+    assert pb.buffer8 == i8(3)
+    assert pb.buffer1 == i32(4)
+    assert pb.buffer2 == f32(5)
+    assert pb.buffer3 == c32(9)
+    assert pb.buffer4 == f64(6)
+    assert pb.buffer5 == i16(7)
+    assert pb.buffer6 == i64(8)
+    assert pb.buffer7 == c64(10)
+
+    fill_buffer(b)
+    print(pb.buffer8)
+    print(pb.buffer1)
+    print(pb.buffer2)
+    print(pb.buffer3)
+    print(pb.buffer4)
+    print(pb.buffer5)
+    print(pb.buffer6)
+    print(pb.buffer7)
+    assert pb.buffer8 == i8(8)
+    assert pb.buffer1 == i32(9)
+    assert pb.buffer2 == f32(10)
+    assert pb.buffer3 == c32(14) + c32(15j)
+    assert pb.buffer4 == f64(11)
+    assert pb.buffer5 == i16(12)
+    assert pb.buffer6 == i64(13)
+    assert pb.buffer7 == c64(16) + c64(17j)
+
+
+f()

integration_tests/structs_19b.c

@@ -0,0 +1,31 @@
+#include <stdlib.h>
+#include <complex.h>
+#include "structs_19b.h"
+
+
+struct buffer_c {
+    int8_t buffer8;
+    int32_t buffer1;
+    float buffer2;
+    float complex buffer3;
+    double buffer4;
+    int16_t buffer5;
+    int64_t buffer6;
+    double complex buffer7;
+};
+
+void fill_buffer(void* buffer_cptr) {
+    struct buffer_c* buffer_clink_ = (struct buffer_c*) buffer_cptr;
+    buffer_clink_->buffer8 = 8;
+    buffer_clink_->buffer1 = 9;
+    buffer_clink_->buffer2 = 10.0;
+    buffer_clink_->buffer3 = CMPLXF(14.0, 15.0);
+    buffer_clink_->buffer4 = 11.0;
+    buffer_clink_->buffer5 = 12;
+    buffer_clink_->buffer6 = 13;
+    buffer_clink_->buffer7 = CMPLXL(16.0, 17.0);
+}
+
+void* get_buffer() {
+    return malloc(sizeof(struct buffer_c));
+}

integration_tests/structs_19b.h

@@ -0,0 +1,4 @@
+#include <inttypes.h>
+
+void fill_buffer(void* buffer_cptr);
+void* get_buffer();

src/runtime/ltypes/ltypes.py

@@ -155,6 +155,12 @@ def inner_func():
 
 # C interoperation support
 
+class c_float_complex(ctypes.Structure):
+    _fields_ = [("real", ctypes.c_float), ("imag", ctypes.c_float)]
+
+class c_double_complex(ctypes.Structure):
+    _fields_ = [("real", ctypes.c_double), ("imag", ctypes.c_double)]
+
 def convert_type_to_ctype(arg):
     if arg == f64:
         return ctypes.c_double
@@ -172,6 +178,10 @@ def convert_type_to_ctype(arg):
         return ctypes.c_void_p
     elif arg == str:
         return ctypes.c_char_p
+    elif arg == c32:
+        return c_float_complex
+    elif arg == c64:
+        return c_double_complex
     elif arg is None:
         raise NotImplementedError("Type cannot be None")
     elif isinstance(arg, Array):
@@ -328,9 +338,23 @@ def __init__(self, ctypes_ptr_):
     def __getattr__(self, name: str):
         if name == "ctypes_ptr":
             return self.__dict__[name]
-        return self.ctypes_ptr.contents.__getattribute__(name)
+        value = self.ctypes_ptr.contents.__getattribute__(name)
+        if isinstance(value, (c_float_complex, c_double_complex)):
+            value = complex(value.real, value.imag)
+        return value
 
     def __setattr__(self, name: str, value):
+        name_ = self.ctypes_ptr.contents.__getattribute__(name)
+        if isinstance(value, complex):
+            if isinstance(name_, c_float_complex):
+                value = c_float_complex(value.real, value.imag)
+            elif isinstance(name_, c_double_complex):
+                value = c_double_complex(value.real, value.imag)
+        else:
+            if isinstance(name_, c_float_complex):
+                value = c_float_complex(value.real, 0.0)
+            elif isinstance(name_, c_double_complex):
+                value = c_double_complex(value.real, 0.0)
         self.ctypes_ptr.contents.__setattr__(name, value)
 
 def c_p_pointer(cptr, targettype):