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package main
/*
#include <stdio.h>
int fortytwo(void);
#include "main.h"
#include "test.h"
int mul(int, int);
#include <string.h>
#cgo CFLAGS: -DSOME_CONSTANT=17
#define someDefine -5 + 2 * 7
bool someBool;
*/
import "C"
// int headerfunc(int a) { return a + 1; }
// static int headerfunc_static(int a) { return a - 1; }
import "C"
import "unsafe"
func main() {
println("fortytwo:", C.fortytwo())
println("add:", C.add(C.int(3), 5))
var x C.myint = 3
println("myint:", x, C.myint(5))
println("myint size:", int(unsafe.Sizeof(x)))
var y C.longlong = -(1 << 40)
println("longlong:", y)
println("global:", C.global)
println("defined ints:", C.CONST_INT, C.CONST_INT2)
println("defined floats:", C.CONST_FLOAT, C.CONST_FLOAT2)
println("defined string:", C.CONST_STRING)
println("defined char:", C.CONST_CHAR)
println("defined expr:", C.someDefine)
var ptr C.intPointer
var n C.int = 15
ptr = C.intPointer(&n)
println("15:", *ptr)
C.store(25, &n)
println("25:", *ptr)
cb := C.binop_t(C.add)
println("callback 1:", C.doCallback(20, 30, cb))
cb = C.binop_t(C.mul)
println("callback 2:", C.doCallback(20, 30, cb))
genericCallbackCall[int]()
// variadic functions
println("variadic0:", C.variadic0())
println("variadic2:", C.variadic2(3, 5))
// functions in the header C snippet
println("headerfunc:", C.headerfunc(5))
println("static headerfunc:", C.headerfunc_static(5))
headerfunc_2()
// equivalent types
var goInt8 int8 = 5
var _ C.int8_t = goInt8
var _ bool = C.someBool
var _ C._Bool = C.someBool
// more globals
println("bool:", C.globalBool, C.globalBool2 == true)
println("float:", C.globalFloat)
println("double:", C.globalDouble)
println("complex float:", C.globalComplexFloat)
println("complex double:", C.globalComplexDouble)
println("complex long double:", C.globalComplexLongDouble)
println("char match:", C.globalChar == 100)
var voidPtr unsafe.Pointer = C.globalVoidPtrNull
println("void* match:", voidPtr == nil, C.globalVoidPtrNull == nil, (*C.int)(C.globalVoidPtrSet) == &C.global)
println("int64_t match:", C.globalInt64 == C.int64_t(-(2<<40)))
// complex types
println("struct:", C.int(unsafe.Sizeof(C.globalStruct)) == C.globalStructSize, C.globalStruct.s, C.globalStruct.l, C.globalStruct.f)
var _ [3]C.short = C.globalArray
println("array:", C.globalArray[0], C.globalArray[1], C.globalArray[2])
println("union:", C.int(unsafe.Sizeof(C.globalUnion)) == C.globalUnionSize)
C.unionSetShort(22)
println("union s:", *C.globalUnion.unionfield_s())
C.unionSetFloat(C.float(6.28))
println("union f (C.float):", *C.globalUnion.unionfield_f())
C.unionSetFloat(float32(3.14))
println("union f (float32):", *C.globalUnion.unionfield_f())
C.unionSetData(5, 8, 1)
data := C.globalUnion.unionfield_data()
println("union global data:", data[0], data[1], data[2])
returnedUnion := printUnion(C.globalUnion)
println("union field:", *returnedUnion.unionfield_f())
var _ C.union_joined = C.globalUnion
printBitfield(&C.globalBitfield)
C.globalBitfield.set_bitfield_a(7)
C.globalBitfield.set_bitfield_b(0)
C.globalBitfield.set_bitfield_c(0xff)
printBitfield(&C.globalBitfield)
// elaborated type
p := C.struct_point2d{x: 3, y: 5}
println("struct:", p.x, p.y)
// multiple anonymous structs (inside a typedef)
var _ C.point2d_t = C.point2d_t{x: 3, y: 5}
var _ C.point3d_t = C.point3d_t{x: 3, y: 5, z: 7}
// nested structs/unions
var _ C.tagged_union_t
var _ C.nested_struct_t
var _ C.nested_union_t
// recursive types, test using a linked list
list := &C.list_t{n: 3, next: &C.struct_list_t{n: 6, next: &C.list_t{n: 7, next: nil}}}
for list != nil {
println("n in chain:", list.n)
list = (*C.list_t)(list.next)
}
// named enum
var _ C.enum_option = C.optionA
var _ C.option_t = C.optionA
println("option:", C.globalOption)
println("option A:", C.optionA)
println("option B:", C.optionB)
println("option C:", C.optionC)
println("option D:", C.optionD)
println("option E:", C.optionE)
println("option F:", C.optionF)
println("option G:", C.optionG)
// anonymous enum
var _ C.option2_t = C.option2A
var _ C.option3_t = C.option3A
println("option 2A:", C.option2A)
println("option 3A:", C.option3A)
// anonymous structs and enums in multiple Go files
var _ C.teststruct
var _ C.testenum
// Check that enums are considered the same width in C and CGo.
println("enum width matches:", unsafe.Sizeof(C.option2_t(0)) == uintptr(C.smallEnumWidth))
// Check whether CFLAGS are correctly passed on to compiled C files.
println("CFLAGS value:", C.cflagsConstant)
// Check array-to-pointer decaying. This signature:
// void arraydecay(int buf1[5], int buf2[3][8], int buf3[4][7][2]);
// decays to:
// void arraydecay(int *buf1, int *buf2[8], int *buf3[7][2]);
C.arraydecay((*C.int)(nil), (*[8]C.int)(nil), (*[7][2]C.int)(nil))
// Test CGo builtins like C.CString.
cstr := C.CString("string passed to C")
println("cstr length:", C.strlen(cstr))
gostr := C.GoString(cstr)
println("C.CString:", gostr)
charBuf := C.GoBytes(unsafe.Pointer(&C.globalChars[0]), 4)
println("C.charBuf:", charBuf[0], charBuf[1], charBuf[2], charBuf[3])
binaryString := C.GoStringN(&C.globalChars[0], 4)
println("C.CStringN:", len(binaryString), binaryString[0], binaryString[1], binaryString[2], binaryString[3])
// Test whether those builtins also work with zero length data.
println("C.GoString(nil):", C.GoString(nil))
println("len(C.GoStringN(nil, 0)):", len(C.GoStringN(nil, 0)))
println("len(C.GoBytes(nil, 0)):", len(C.GoBytes(nil, 0)))
// libc: test whether C functions work at all.
buf1 := []byte("foobar\x00")
buf2 := make([]byte, len(buf1))
C.strcpy((*C.char)(unsafe.Pointer(&buf2[0])), (*C.char)(unsafe.Pointer(&buf1[0])))
println("copied string:", string(buf2[:C.strlen((*C.char)(unsafe.Pointer(&buf2[0])))]))
// libc: test basic stdio functionality
putsBuf := []byte("line written using C puts\x00")
C.puts((*C.char)(unsafe.Pointer(&putsBuf[0])))
}
func printUnion(union C.joined_t) C.joined_t {
data := union.unionfield_data()
println("union local data: ", data[0], data[1], data[2])
*union.unionfield_s() = -33
println("union s:", data[0] == -33)
*union.unionfield_f() = 6.28
println("union f:", *union.unionfield_f())
return union
}
//export mul
func mul(a, b C.int) C.int {
return a * b
}
func printBitfield(bitfield *C.bitfield_t) {
println("bitfield a:", bitfield.bitfield_a())
println("bitfield b:", bitfield.bitfield_b())
println("bitfield c:", bitfield.bitfield_c())
println("bitfield d:", bitfield.d)
println("bitfield e:", bitfield.e)
}
type Int interface {
int | uint
}
func genericCallbackCall[T Int]() {
println("callback inside generic function:", C.doCallback(20, 30, C.binop_t(C.add)))
}
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