eina: add accessors for c arrays

This adds a new API which can be used to get access to a carray via the eina_accessor API.

src/lib/eina/eina_accessor.c

@@ -189,3 +189,64 @@ eina_accessor_unlock(Eina_Accessor *accessor)
       return accessor->unlock(accessor);
    return EINA_TRUE;
 }
+
+typedef struct _Eina_Accessor_CArray_Length Eina_Accessor_CArray_Length;
+
+struct _Eina_Accessor_CArray_Length
+{
+   Eina_Accessor accessor;
+
+   void** array;
+   void** current;
+
+   void** end;
+   unsigned int step;
+};
+
+static Eina_Bool
+eina_carray_length_accessor_get_at(Eina_Accessor_CArray_Length *accessor, unsigned int idx, void **data)
+{
+   if (accessor->array + idx*accessor->step >= accessor->end)
+     return EINA_FALSE;
+
+   memcpy(data, (void*) accessor->array + idx*accessor->step, accessor->step);
+   accessor->current += accessor->step;
+
+   return EINA_TRUE;
+}
+
+static void**
+eina_carray_length_accessor_get_container(Eina_Accessor_CArray_Length *accessor)
+{
+   return accessor->array;
+}
+
+static void
+eina_carray_length_accessor_free(Eina_Accessor_CArray_Length *accessor)
+{
+   free(accessor);
+}
+
+EAPI Eina_Accessor *
+eina_carray_length_accessor_new(void** array, unsigned int step, unsigned int length)
+{
+   Eina_Accessor_CArray_Length *accessor;
+
+   accessor = calloc(1, sizeof (Eina_Accessor_CArray_Length));
+   if (!accessor) return NULL;
+
+   EINA_MAGIC_SET(&accessor->accessor, EINA_MAGIC_ACCESSOR);
+
+   accessor->array = array;
+   accessor->current = accessor->array;
+   accessor->end = accessor->current + length * step;
+   accessor->step = step;
+
+   accessor->accessor.version = EINA_ACCESSOR_VERSION;
+   accessor->accessor.get_at = FUNC_ACCESSOR_GET_AT(eina_carray_length_accessor_get_at);
+   accessor->accessor.get_container = FUNC_ACCESSOR_GET_CONTAINER(
+      eina_carray_length_accessor_get_container);
+   accessor->accessor.free = FUNC_ACCESSOR_FREE(eina_carray_length_accessor_free);
+
+   return &accessor->accessor;
+}

src/lib/eina/eina_accessor.h

@@ -348,6 +348,38 @@ EAPI Eina_Bool eina_accessor_unlock(Eina_Accessor *accessor) EINA_ARG_NONNULL(1)
        eina_accessor_data_get((accessor), (counter), (void **)(void *)&(data)); \
        (counter)++)
 
+/**
+ * @brief Creates an Eina_Accessor that wraps a plain fixed size C array
+ *
+ * @param[in] array The array
+ * @param[in] step  The size of one element in the array
+ * @param[in] length The number of elements in the array
+ * @return The accessor that will give access to the passed array
+ *
+ * You can create it like this:
+ * int array[] = {1, 2, 3, 4, 1337, 42};
+ *
+ * Eina_Accessor* accessor = eina_carray_length_accessor_new(array, sizeof(int), sizeof(array)/sizeof(int));
+ *
+ * @since 1.23
+ */
+EAPI Eina_Accessor* eina_carray_length_accessor_new(void** array, unsigned int step, unsigned int length);
+/**
+ * @def EINA_C_ARRAY_ACCESSOR_NEW
+ * @brief Creates an Eina_Accessor that wraps a plain fixed size C array
+ *
+ * @param[in] array The array
+ * @return The accessor that will give access to the passed array
+ *
+ * You can create it like this:
+ * int array[] = {1, 2, 3, 4, 1337, 42};
+ *
+ * Eina_Accessor* accessor = EINA_C_ARRAY_ACCESSOR_NEW(array)
+ *
+ * @since 1.23
+ */
+#define EINA_C_ARRAY_ACCESSOR_NEW(Array) eina_carray_length_accessor_new((void**) Array, sizeof (Array[0]), EINA_C_ARRAY_LENGTH(Array))
+
 /**
  * @}
  */

src/tests/eina/eina_test_accessor.c

@@ -230,10 +230,38 @@ EFL_START_TEST(eina_accessor_list_simple)
 }
 EFL_END_TEST
 
+EFL_START_TEST(eina_accessor_carray_simple)
+{
+   Eina_Accessor *it;
+   int data[] = { 6, 9, 42, 1, 7, 1337, 81, 1664 };
+   int j, c;
+
+   it = EINA_C_ARRAY_ACCESSOR_NEW(data);
+
+   EINA_ACCESSOR_FOREACH(it, c, j)
+     {
+        ck_assert_int_eq(data[c], j);
+     }
+
+   fail_if(eina_accessor_data_get(it, 5, (void **)&j) != EINA_TRUE);
+   fail_if(j != 1337);
+   fail_if(eina_accessor_data_get(it, 3, (void **)&j) != EINA_TRUE);
+   fail_if(j != 1);
+   fail_if(eina_accessor_data_get(it, 3, (void **)&j) != EINA_TRUE);
+   fail_if(j != 1);
+   fail_if(eina_accessor_data_get(it, 1, (void **)&j) != EINA_TRUE);
+   fail_if(j != 9);
+   fail_if(eina_accessor_data_get(it, 5, (void **)&j) != EINA_TRUE);
+   fail_if(j != 1337);
+
+   eina_accessor_free(it);
+}
+EFL_END_TEST
 void
 eina_test_accessor(TCase *tc)
 {
    tcase_add_test(tc, eina_accessor_array_simple);
    tcase_add_test(tc, eina_accessor_inlist_simple);
    tcase_add_test(tc, eina_accessor_list_simple);
+   tcase_add_test(tc, eina_accessor_carray_simple);
 }