Allow the port to allocate/deallocate the heap

This is a first step towards pushing the Jerryscript state into objects
the port can allocate and clear as opposed to static memory.

JerryScript-DCO-1.0-Signed-off-by: François Baldassari [email protected]

Author: François Baldassari

jerry-core/jerry-port.h

@@ -24,6 +24,12 @@ extern "C"
 {
 #endif /* !__cplusplus */
 
+/**
+ * Forward definition of heap data structure
+ */
+struct mem_heap;
+typedef struct mem_heap mem_heap_t;
+
 /** \addtogroup jerry_port Jerry engine port
  * @{
  */
@@ -37,6 +43,16 @@ int jerry_port_putchar (int c);
 
 void jerry_port_abort (void);
 
+
+/**
+ * Target port functions for memory management
+ */
+mem_heap_t *jerry_port_init_heap (void);
+
+void jerry_port_finalize_heap (mem_heap_t *mem_heap);
+
+mem_heap_t *jerry_port_get_heap (void);
+
 /**
  * @}
  */

jerry-core/jerry.c

@@ -2444,15 +2444,3 @@ jerry_api_get_string_size (const jerry_api_string_t *str_p) /**< input string */
   return ecma_string_get_size ((ecma_string_t *) str_p);
 } /* jerry_api_get_string_size */
 
-/**
- * Get length of Jerry string
- *
- * @return number of characters in the string
- */
-jerry_api_length_t
-jerry_api_get_string_length (const jerry_api_string_t *str_p) /**< input string */
-{
-  jerry_assert_api_available ();
-
-  return ecma_string_get_length ((ecma_string_t *) str_p);
-} /* jerry_api_get_string_length */

jerry-core/mem/mem-heap-internal.h

@@ -0,0 +1,81 @@
+/* Copyright 2014 Samsung Electronics Co., Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef MEM_HEAP_INTERNAL_H
+#define MEM_HEAP_INTERNAL_H
+
+#ifndef MEM_HEAP_INTERNAL
+# error "The header is for internal routines of memory heap component. Please, don't use the routines directly."
+#endif /* !MEM_HEAP_INTERNAL */
+
+#include "mem-allocator.h"
+#include "mem-config.h"
+
+/** \addtogroup mem Memory allocation
+ * @{
+ */
+
+/* Calculate heap area size, leaving space for a pointer to the free list */
+#define MEM_HEAP_AREA_SIZE (MEM_HEAP_SIZE - MEM_ALIGNMENT)
+#define MEM_HEAP_END_OF_LIST ((mem_heap_free_t *const) ~((uint32_t) 0x0))
+
+/**
+ *  Free region node
+ */
+typedef struct
+{
+  uint32_t next_offset; /* Offset of next region in list */
+  uint32_t size; /* Size of region */
+} mem_heap_free_t;
+
+#ifdef MEM_HEAP_PTR_64
+#define MEM_HEAP_GET_OFFSET_FROM_ADDR(h, p) ((uint32_t) ((uint8_t *) (p) - (uint8_t *) (h)->area))
+#define MEM_HEAP_GET_ADDR_FROM_OFFSET(h, u) ((mem_heap_free_t *) &(h)->area[u])
+#else
+/* In this case we simply store the pointer, since it fits anyway. */
+#define MEM_HEAP_GET_OFFSET_FROM_ADDR(h, p) ((uint32_t) (p))
+#define MEM_HEAP_GET_ADDR_FROM_OFFSET(h, u) ((mem_heap_free_t *)(u))
+#endif
+
+/**
+ * Heap structure
+ */
+struct mem_heap
+{
+  mem_heap_free_t first;
+  /* This is used to speed up deallocation. */
+  mem_heap_free_t *list_skip_p;
+  /**
+   * Size of allocated regions
+   */
+  size_t allocated_size;
+
+  /**
+   * Current limit of heap usage, that is upon being reached, causes call of "try give memory back" callbacks
+   */
+  size_t limit;
+
+  /**
+   * Heap area
+   */
+  uint8_t area[MEM_HEAP_AREA_SIZE] __attribute__ ((aligned (MEM_ALIGNMENT)));
+};
+
+
+/**
+ * @}
+ */
+
+#endif /* MEM_HEAP_INTERNAL_H */