General purpose memory allocator for linker.

Add basic general purpose memory allocator to
 linker in order to enable usage of other libraries
 like libziparchive.

Change-Id: I4a680ebb36ed5ba67c61249f81dba9f567808434

linker/linker_memory.cpp

@@ -0,0 +1,38 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * 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.
+ */
+
+#include "linker_allocator.h"
+
+#include <stdlib.h>
+
+static LinkerMemoryAllocator g_linker_allocator;
+
+void* malloc(size_t byte_count) {
+  return g_linker_allocator.alloc(byte_count);
+}
+
+void* calloc(size_t item_count, size_t item_size) {
+  return g_linker_allocator.alloc(item_count*item_size);
+}
+
+void* realloc(void* p, size_t byte_count) {
+  return g_linker_allocator.realloc(p, byte_count);
+}
+
+void free(void* ptr) {
+  g_linker_allocator.free(ptr);
+}
+