VM: added function and data declarations

vm.h

@@ -0,0 +1,53 @@
+#ifndef VM_H
+#define VM_H
+
+#define STACK_MAX 1024
+
+// Primitive types for garbage collection
+enum garbageData {
+  GARBAGE_INT,
+  GARBAGE_PAIR,
+};
+
+// Holds type and value data for the virtual machine
+struct garbageObject {
+  enum garbageData type;
+  struct garbageObject *next;
+
+  union {
+    int value;
+
+    struct {
+      struct garbageObject *head;
+      struct garbageObject *tail;
+    };
+  };
+};
+
+// Virtual machine hold the stack to trace references
+struct virtualMachine {
+  int stackSize;
+  struct garbageObject *head;
+  struct garbageObject *stack[STACK_MAX];
+};
+
+// Create a new garbageObject
+struct garbageObject *initGarbage(struct virtualMachine *vm,
+                                  enum garbageData type);
+
+// Create a new VM
+struct virtualMachine *initVM();
+
+// Generic function to push data onto the VM stack
+void push(struct virtualMachine *vm, struct garbageObject *value);
+
+// Pop data from the VM stack
+struct garbageObject *pop(struct virtualMachine *vm);
+
+// Push a GARBAGE_INT onto the VM stack
+void pushInt(struct virtualMachine *vm, int value);
+
+// Push a GARBAGE_PAIR onto the VM stack
+struct garbageObject *pushPair(struct virtualMachine *vm);
+
+#endif /* VM_H */