How do you golang use c or c++ code?
-
Please provide a simple example of the use of the function from \c+++ in the golang programme. For example, c/ c++ will sayHello return value -
"Hi, Roman, this is a function."
♪
That's what I want in the golang program. How do you do that?
Please provide examples. Thank you.
-
Explain the class.
// foo.hpp class cxxFoo { public: int a; cxxFoo(int _a):a(_a){}; ~cxxFoo(){}; void Bar(); };// foo.cpp
#include <iostream>
#include "foo.hpp"
void
cxxFoo::Bar(void){
std::cout<<this->a<<std::endl;
}
Interface C
// foo.h
#ifdef __cplusplus
extern "C" {
#endif
typedef void* Foo;
Foo FooInit(void);
void FooFree(Foo);
void FooBar(Foo);
#ifdef __cplusplus
}
#endif
Implementation
//cfoo.cpp
#include "foo.hpp"
#include "foo.h"
Foo FooInit()
{
cxxFoo * ret = new cxxFoo(1);
return (void*)ret;
}
void FooFree(Foo f)
{
cxxFoo * foo = (cxxFoo*)f;
delete foo;
}
void FooBar(Foo f)
{
cxxFoo * foo = (cxxFoo*)f;
foo->Bar();
}
Go file
package foo
// #include "foo.h"
import "C"
import "unsafe"
type GoFoo struct {
foo C.Foo;
}
func New()(GoFoo){
var ret GoFoo;
ret.foo = C.FooInit();
return ret;
}
func (f GoFoo)Free(){
C.FooFree(unsafe.Pointer(f.foo));
}
func (f GoFoo)Bar(){
C.FooBar(unsafe.Pointer(f.foo));
}
Makefile
// makefile
TARG=foo
CGOFILES=foo.go
include $(GOROOT)/src/Make.$(GOARCH)
include $(GOROOT)/src/Make.pkg
foo.o:foo.cpp
g++ $(CGO_CFLAGS$(GOARCH)) -fPIC -O2 -o $@ -c $(CGO_CFLAGS) $<
cfoo.o:cfoo.cpp
g++ $(CGO_CFLAGS$(GOARCH)) -fPIC -O2 -o $@ -c $(CGO_CFLAGS) $<
CGO_LDFLAGS+=-lstdc++
$(elem)_foo.so: foo.cgo4.o foo.o cfoo.o
gcc $(CGO_CFLAGS$(GOARCH)) $(CGO_LDFLAGS$(GOOS)) -o $@ $^ $(CGO_LDFLAGS)
Testing
// foo_test.go
package foo
import "testing"
func TestFoo(t *testing.T){
foo := New();
foo.Bar();
foo.Free();
}
Library installation
gotest
rm -f _test/foo.a gotest.6
6g -o gotest.6 foo.cgo1.go foo.cgo2.go foo_test.go
rm -f _test/foo.a
gopack grc _test/foo.a gotest.6 foo.cgo3.6
1
PASS
