ch2-05: 增加Go对象到C++对象例子

examples/ch2-05/class-go2cc/goobj.go

@@ -0,0 +1,53 @@
+package main
+
+import (
+	"sync"
+)
+
+type ObjectId int32
+
+var refs struct {
+	sync.Mutex
+	objs map[ObjectId]interface{}
+	next ObjectId
+}
+
+func init() {
+	refs.Lock()
+	defer refs.Unlock()
+
+	refs.objs = make(map[ObjectId]interface{})
+	refs.next = 1000
+}
+
+func NewObjectId(obj interface{}) ObjectId {
+	refs.Lock()
+	defer refs.Unlock()
+
+	id := refs.next
+	refs.next++
+
+	refs.objs[id] = obj
+	return id
+}
+
+func (id ObjectId) IsNil() bool {
+	return id == 0
+}
+
+func (id ObjectId) Get() interface{} {
+	refs.Lock()
+	defer refs.Unlock()
+
+	return refs.objs[id]
+}
+
+func (id ObjectId) Free() interface{} {
+	refs.Lock()
+	defer refs.Unlock()
+
+	obj := refs.objs[id]
+	delete(refs.objs, id)
+
+	return obj
+}

examples/ch2-05/class-go2cc/main.cc

@@ -0,0 +1,14 @@
+#include "person.h"
+
+#include <stdio.h>
+
+extern "C" void Main() {
+	auto p = Person::New("gopher", 10);
+
+	char buf[64];
+	char* name = p->GetName(buf, sizeof(buf)-1);
+	int age = p->GetAge();
+
+	printf("%s, %d years old.\n", name, age);
+	p->Delete();
+}

examples/ch2-05/class-go2cc/main.go

@@ -0,0 +1,9 @@
+package main
+
+// #cgo CXXFLAGS: -std=c++11
+// extern void Main();
+import "C"
+
+func main() {
+	C.Main()
+}

examples/ch2-05/class-go2cc/persion.go

@@ -0,0 +1,22 @@
+package main
+
+type Person struct {
+	name string
+	age  int
+}
+
+func NewPerson(name string, age int) *Person {
+	return &Person{
+		name: name,
+		age:  age,
+	}
+}
+
+func (p *Person) Set(name string, age int) {
+	p.name = name
+	p.age = age
+}
+
+func (p *Person) Get() (name string, age int) {
+	return p.name, p.age
+}

examples/ch2-05/class-go2cc/person.cc

@@ -0,0 +1 @@
+#include "person.h"

examples/ch2-05/class-go2cc/person.h

@@ -0,0 +1,23 @@
+
+extern "C" {
+	#include "./person_capi.h"
+}
+
+struct Person {
+	static Person* New(const char* name, int age) {
+		return (Person*)person_new((char*)name, age);
+	}
+	void Delete() {
+		person_delete(person_handle_t(this));
+	}
+
+	void Set(char* name, int age) {
+		person_set(person_handle_t(this), name, age);
+	}
+	char* GetName(char* buf, int size) {
+		return person_get_name(person_handle_t(this), buf, size);
+	}
+	int GetAge() {
+		return person_get_age(person_handle_t(this));
+	}
+};

examples/ch2-05/class-go2cc/person_capi.go

@@ -0,0 +1,42 @@
+package main
+
+//#include "./person_capi.h"
+import "C"
+import "unsafe"
+
+//export person_new
+func person_new(name *C.char, age C.int) C.person_handle_t {
+	id := NewObjectId(NewPerson(C.GoString(name), int(age)))
+	return C.person_handle_t(id)
+}
+
+//export person_delete
+func person_delete(h C.person_handle_t) {
+	ObjectId(h).Free()
+}
+
+//export person_set
+func person_set(h C.person_handle_t, name *C.char, age C.int) {
+	p := ObjectId(h).Get().(*Person)
+	p.Set(C.GoString(name), int(age))
+}
+
+//export person_get_name
+func person_get_name(h C.person_handle_t, buf *C.char, size C.int) *C.char {
+	p := ObjectId(h).Get().(*Person)
+	name, _ := p.Get()
+
+	n := int(size) - 1
+	bufSlice := ((*[1 << 31]byte)(unsafe.Pointer(buf)))[0:n:n]
+	n = copy(bufSlice, []byte(name))
+	bufSlice[n] = 0
+
+	return buf
+}
+
+//export person_get_age
+func person_get_age(h C.person_handle_t) C.int {
+	p := ObjectId(h).Get().(*Person)
+	_, age := p.Get()
+	return C.int(age)
+}

examples/ch2-05/class-go2cc/person_capi.h

@@ -0,0 +1,10 @@
+#include <stdint.h>
+
+typedef uintptr_t person_handle_t;
+
+person_handle_t person_new(char* name, int age);
+void person_delete(person_handle_t p);
+
+void person_set(person_handle_t p, char* name, int age);
+char* person_get_name(person_handle_t p, char* buf, int size);
+int person_get_age(person_handle_t p);