Add write_file () syscall, CE implement redirections, libarena arena_realloc ()

libarena/arena.c

@@ -76,3 +76,15 @@ void* arena_malloc (struct arena* arena, size_t size) {
   arena->end->size += size1;
   return result;
 }
+
+void* arena_realloc (struct arena* arena, void* memory, size_t prev_size, size_t new_size) {
+  if (new_size <= prev_size)
+    return memory;
+
+  void* new_memory = arena_malloc (arena, new_size);
+
+  for (size_t i = 0; i < prev_size; i++)
+    ((uint8_t*)new_memory)[i] = ((uint8_t*)memory)[i];
+
+  return new_memory;
+}

libarena/arena.h

@@ -23,4 +23,6 @@ void arena_destroy (struct arena* arena);
 
 void* arena_malloc (struct arena* arena, size_t size);
 
+void* arena_realloc (struct arena* arena, void* memory, size_t prev_size, size_t new_size);
+
 #endif // _LIBARENA_ARENA_H