change gc heap API and hide sturctures.

include/picrin/gc.h

@@ -12,27 +12,10 @@ extern "C" {
 #define PIC_GC_UNMARK 0
 #define PIC_GC_MARK 1
 
-union header {
-  struct {
-    union header *ptr;
-    size_t size;
-    unsigned int mark : 1;
-  } s;
-  long alignment[4];
-};
+struct pic_heap;
 
-struct heap_page {
-  union header *basep, *endp;
-  struct heap_page *next;
-};
-
-struct pic_heap {
-  union header base, *freep;
-  struct heap_page *pages;
-};
-
-void init_heap(struct pic_heap *);
-void finalize_heap(struct pic_heap *);
+struct pic_heap *heap_open();
+void heap_close(struct pic_heap *);
 
 #if defined(__cplusplus)
 }

src/gc.c

@@ -23,8 +23,27 @@
 # include <string.h>
 #endif
 
+union header {
+  struct {
+    union header *ptr;
+    size_t size;
+    unsigned int mark : 1;
+  } s;
+  long alignment[4];
+};
+
+struct heap_page {
+  union header *basep, *endp;
+  struct heap_page *next;
+};
+
+struct pic_heap {
+  union header base, *freep;
+  struct heap_page *pages;
+};
+
 void
-init_heap(struct pic_heap *heap)
+heap_init(struct pic_heap *heap)
 {
   heap->base.s.ptr = &heap->base;
   heap->base.s.size = 0; /* not 1, since it must never be used for allocation */
@@ -38,8 +57,18 @@ init_heap(struct pic_heap *heap)
 #endif
 }
 
+struct pic_heap *
+heap_open()
+{
+  struct pic_heap *heap;
+
+  heap = (struct pic_heap *)calloc(1, sizeof(struct pic_heap));
+  heap_init(heap);
+  return heap;
+}
+
 void
-finalize_heap(struct pic_heap *heap)
+heap_close(struct pic_heap *heap)
 {
   struct heap_page *page;
 

src/state.c

@@ -48,8 +48,7 @@ pic_open(int argc, char *argv[], char **envp)
   pic->rlen = PIC_RESCUE_SIZE;
 
   /* memory heap */
-  pic->heap = (struct pic_heap *)calloc(1, sizeof(struct pic_heap));
-  init_heap(pic->heap);
+  pic->heap = heap_open();
 
   /* symbol table */
   pic->syms = xh_new_str();
@@ -152,8 +151,7 @@ pic_close(pic_state *pic)
   xh_destroy(pic->macros);
 
   /* free heaps */
-  finalize_heap(pic->heap);
-  free(pic->heap);
+  heap_close(pic->heap);
 
   /* free symbol names */
   for (xh_begin(pic->sym_names, &it); ! xh_isend(&it); xh_next(&it)) {