From a6f561d66ed2e791df1084a982a50494c98e02b5 Mon Sep 17 00:00:00 2001
From: Yuichi Nishiwaki <yuichi.nishiwaki@gmail.com>
Date: Sun, 13 Oct 2013 17:25:36 +0900
Subject: [PATCH] change the type of argument pic_gc_protect accepts

---
 include/picrin.h       |  4 +++
 include/picrin/value.h |  1 +
 src/gc.c               | 57 ++++++++++++++++++++++++++----------------
 3 files changed, 40 insertions(+), 22 deletions(-)

diff --git a/include/picrin.h b/include/picrin.h
index 76241b67..626a52a4 100644
--- a/include/picrin.h
+++ b/include/picrin.h
@@ -29,6 +29,10 @@ void *pic_alloc(pic_state *, size_t);
 struct pic_object *pic_obj_alloc(pic_state *, size_t, enum pic_tt);
 void pic_free(pic_state *, void *);
 
+void pic_gc_protect(pic_state *, pic_value);
+int pic_gc_arena_preserve(pic_state *);
+void pic_gc_arena_restore(pic_state *, int);
+
 pic_state *pic_open();
 void pic_close(pic_state *);
 
diff --git a/include/picrin/value.h b/include/picrin/value.h
index b2acba8b..6334b5b7 100644
--- a/include/picrin/value.h
+++ b/include/picrin/value.h
@@ -52,6 +52,7 @@ struct pic_proc {
   } u;
 };
 
+#define pic_object_ptr(o) ((struct pic_object *)o.u.data)
 #define pic_pair_ptr(o) ((struct pic_pair *)o.u.data)
 #define pic_symbol_ptr(o) ((struct pic_symbol *)o.u.data)
 #define pic_proc_ptr(o) ((struct pic_proc *)o.u.data)
diff --git a/src/gc.c b/src/gc.c
index c51a2e8c..482b95f8 100644
--- a/src/gc.c
+++ b/src/gc.c
@@ -39,6 +39,40 @@ pic_free(pic_state *pic, void *ptr)
   free(ptr);
 }
 
+static void
+gc_protect(pic_state *pic, struct pic_object *obj)
+{
+  if (pic->arena_idx >= PIC_ARENA_SIZE) {
+    pic_raise(pic, "arena overflow");
+  }
+  pic->arena[pic->arena_idx++] = obj;
+}
+
+void
+pic_gc_protect(pic_state *pic, pic_value v)
+{
+  struct pic_object *obj;
+
+  if (v.type != PIC_VTYPE_HEAP) {
+    return;
+  }
+  obj = pic_object_ptr(v);
+
+  gc_protect(pic, obj);
+}
+
+int
+pic_gc_arena_preserve(pic_state *pic)
+{
+  return pic->arena_idx;
+}
+
+void
+pic_gc_arena_restore(pic_state *pic, int state)
+{
+  pic->arena_idx = state;
+}
+
 static void *
 pic_gc_alloc(pic_state *pic, size_t size)
 {
@@ -104,27 +138,6 @@ pic_obj_alloc(pic_state *pic, size_t size, enum pic_tt tt)
   obj = (struct pic_object *)malloc(size);
   obj->tt = tt;
 
-  pic_gc_protect(pic, obj);
+  gc_protect(pic, obj);
   return obj;
 }
-
-void
-pic_gc_protect(pic_state *pic, struct pic_object *obj)
-{
-  if (pic->arena_idx >= PIC_ARENA_SIZE) {
-    pic_raise(pic, "arena overflow");
-  }
-  pic->arena[pic->arena_idx++] = obj;
-}
-
-int
-pic_gc_arena_preserve(pic_state *pic)
-{
-  return pic->arena_idx;
-}
-
-void
-pic_gc_arena_restore(pic_state *pic, int state)
-{
-  pic->arena_idx = state;
-}