Initial commit

example/MObject.c

@@ -0,0 +1,86 @@
+#include "MObject.h"
+
+#include <stdlib.h>
+#include <string.h>
+#include <stdint.h>
+
+static struct Object* alloc(struct Object* self);
+static struct Object* retain(struct Object* self);
+static struct Object* release(struct Object* self);
+
+struct Method MObject_meta_methods[] = {
+    { .sel = "alloc", .impl = alloc },
+};
+struct Class MObjectMetaClass = {
+    .class = &MObjectMetaClass,
+    .name = "MObject(meta)",
+    .super = nullptr,
+    .methods = MObject_meta_methods,
+    .methods_count = sizeof(MObject_meta_methods) / sizeof(struct Method),
+};
+
+struct Method MObject_methods[] = {
+    { .sel = "retain", .impl = retain },
+    { .sel = "release", .impl = release },
+};
+struct Class MObject = {
+    .class = &MObjectMetaClass,
+    .name = "MObject",
+    .super = nullptr,
+    .methods = MObject_methods,
+    .methods_count = sizeof(MObject_methods) / sizeof(struct Method),
+};
+
+struct Header
+{
+    size_t retain_count;
+};
+
+static struct Object* alloc(struct Object* self)
+{
+    if (!self) {
+        return nullptr;
+    }
+
+    struct Class* class = (struct Class*)self;
+
+    auto size = sizeof(struct Header) + sizeof(struct Object);
+    void* mem = malloc(size);
+    memset(mem, 0, size);
+
+    struct Header* header = (struct Header*)mem;
+    header->retain_count = 1;
+
+    struct Object* obj = (struct Object*)((uintptr_t)mem + sizeof(struct Header));
+    obj->class = class;
+
+    return obj;
+}
+
+static struct Object* retain(struct Object* self)
+{
+    if (!self) {
+        return nullptr;
+    }
+
+    struct Header* header = (struct Header*)((uintptr_t)self - sizeof(struct Header));
+    header->retain_count += 1;
+
+    return self;
+}
+
+static struct Object* release(struct Object* self)
+{
+    if (!self) {
+        return nullptr;
+    }
+
+    struct Header* header = (struct Header*)((uintptr_t)self - sizeof(struct Header));
+    header->retain_count -= 1;
+    if (header->retain_count <= 0) {
+        free(header);
+    }
+
+    return nullptr;
+}
+