1 files changed, 78 insertions, 11 deletions

diff --git a/ext/fiddle/memory_view.c b/ext/fiddle/memory_view.c
index 172b1f18fc..fa66fc2c7b 100644
--- a/ext/fiddle/memory_view.c
+++ b/ext/fiddle/memory_view.c
@@ -1,9 +1,11 @@
-#include <stdbool.h>
-#include <ruby/ruby.h>
+#include <fiddle.h>
 
 #ifdef HAVE_RUBY_MEMORY_VIEW_H
-# include <ruby/memory_view.h>
-#endif
+
+#include <stdbool.h>
+#include <ruby/ruby.h>
+#include <ruby/encoding.h>
+#include <ruby/memory_view.h>
 
 #if SIZEOF_INTPTR_T == SIZEOF_LONG_LONG
 #   define INTPTR2NUM LL2NUM
@@ -16,9 +18,6 @@
 #   define UINTPTR2NUM UINT2NUM
 #endif
 
-#include <fiddle.h>
-
-#ifdef FIDDLE_MEMORY_VIEW
 VALUE rb_cMemoryView = Qnil;
 
 struct memview_data {
@@ -35,12 +34,25 @@ fiddle_memview_mark(void *ptr)
 }
 
 static void
-fiddle_memview_free(void *ptr)
+fiddle_memview_release(struct memview_data *data)
 {
-    struct memview_data *data = ptr;
+    if (NIL_P(data->view.obj)) return;
+
     rb_memory_view_release(&data->view);
-    if (data->members)
+    data->view.obj = Qnil;
+    data->view.byte_size = 0;
+    if (data->members) {
         xfree(data->members);
+        data->members = NULL;
+        data->n_members = 0;
+    }
+}
+
+static void
+fiddle_memview_free(void *ptr)
+{
+    struct memview_data *data = ptr;
+    fiddle_memview_release(data);
     xfree(ptr);
 }
 
@@ -62,18 +74,40 @@ rb_fiddle_memview_s_allocate(VALUE klass)
     struct memview_data *data;
     VALUE obj = TypedData_Make_Struct(klass, struct memview_data, &fiddle_memview_data_type, data);
     data->view.obj = Qnil;
+    data->view.byte_size = 0;
     data->members = NULL;
     data->n_members = 0;
     return obj;
 }
 
 static VALUE
+rb_fiddle_memview_release(VALUE obj)
+{
+    struct memview_data *data;
+    TypedData_Get_Struct(obj, struct memview_data, &fiddle_memview_data_type, data);
+
+    if (NIL_P(data->view.obj)) return Qnil;
+    fiddle_memview_release(data);
+    return Qnil;
+}
+
+static VALUE
+rb_fiddle_memview_s_export(VALUE klass, VALUE target)
+{
+    ID id_new;
+    CONST_ID(id_new, "new");
+    VALUE memview = rb_funcall(klass, id_new, 1, target);
+    return rb_ensure(rb_yield, memview, rb_fiddle_memview_release, memview);
+}
+
+static VALUE
 rb_fiddle_memview_initialize(VALUE obj, VALUE target)
 {
     struct memview_data *data;
     TypedData_Get_Struct(obj, struct memview_data, &fiddle_memview_data_type, data);
 
     if (!rb_memory_view_get(target, &data->view, 0)) {
+        data->view.obj = Qnil;
         rb_raise(rb_eArgError, "Unable to get a memory view from %+"PRIsVALUE, target);
     }
 
@@ -233,12 +267,44 @@ rb_fiddle_memview_aref(int argc, VALUE *argv, VALUE obj)
     return rb_memory_view_extract_item_members(ptr, data->members, data->n_members);
 }
 
+static VALUE
+rb_fiddle_memview_to_s(VALUE self)
+{
+    struct memview_data *data;
+    const char *raw_data;
+    long byte_size;
+    VALUE string;
+
+    TypedData_Get_Struct(self,
+                         struct memview_data,
+                         &fiddle_memview_data_type,
+                         data);
+
+    if (NIL_P(data->view.obj)) {
+        raw_data = NULL;
+        byte_size = 0;
+    } else {
+        raw_data = data->view.data;
+        byte_size = data->view.byte_size;
+    }
+
+    string = rb_enc_str_new_static(raw_data, byte_size, rb_ascii8bit_encoding());
+    {
+        ID id_memory_view;
+        CONST_ID(id_memory_view, "memory_view");
+        rb_ivar_set(string, id_memory_view, self);
+    }
+    return rb_obj_freeze(string);
+}
+
 void
 Init_fiddle_memory_view(void)
 {
     rb_cMemoryView = rb_define_class_under(mFiddle, "MemoryView", rb_cObject);
     rb_define_alloc_func(rb_cMemoryView, rb_fiddle_memview_s_allocate);
+    rb_define_singleton_method(rb_cMemoryView, "export", rb_fiddle_memview_s_export, 1);
     rb_define_method(rb_cMemoryView, "initialize", rb_fiddle_memview_initialize, 1);
+    rb_define_method(rb_cMemoryView, "release", rb_fiddle_memview_release, 0);
     rb_define_method(rb_cMemoryView, "obj", rb_fiddle_memview_get_obj, 0);
     rb_define_method(rb_cMemoryView, "byte_size", rb_fiddle_memview_get_byte_size, 0);
     rb_define_method(rb_cMemoryView, "readonly?", rb_fiddle_memview_get_readonly, 0);
@@ -249,6 +315,7 @@ Init_fiddle_memory_view(void)
     rb_define_method(rb_cMemoryView, "strides", rb_fiddle_memview_get_strides, 0);
     rb_define_method(rb_cMemoryView, "sub_offsets", rb_fiddle_memview_get_sub_offsets, 0);
     rb_define_method(rb_cMemoryView, "[]", rb_fiddle_memview_aref, -1);
+    rb_define_method(rb_cMemoryView, "to_s", rb_fiddle_memview_to_s, 0);
 }
 
-#endif /* FIDDLE_MEMORY_VIEW */
+#endif /* HAVE_RUBY_MEMORY_VIEW_H */