Get LIBC_MEM and LIBC_STDIO building with aarch64

libc/mem/hook_realloc_in_place.c

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+/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
+│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8                                :vi│
+╞══════════════════════════════════════════════════════════════════════════════╡
+│ Copyright 2023 Justine Alexandra Roberts Tunney                              │
+│                                                                              │
+│ Permission to use, copy, modify, and/or distribute this software for         │
+│ any purpose with or without fee is hereby granted, provided that the         │
+│ above copyright notice and this permission notice appear in all copies.      │
+│                                                                              │
+│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL                │
+│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED                │
+│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE             │
+│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL         │
+│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR        │
+│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER               │
+│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
+│ PERFORMANCE OF THIS SOFTWARE.                                                │
+╚─────────────────────────────────────────────────────────────────────────────*/
+#include "libc/mem/hook.internal.h"
+#include "libc/mem/mem.h"
+#include "third_party/dlmalloc/dlmalloc.h"
+
+void *(*hook_realloc_in_place)(void *, size_t) = dlrealloc_in_place;
+
+/**
+ * Resizes the space allocated for p to size n, only if this can be
+ * done without moving p (i.e., only if there is adjacent space
+ * available if n is greater than p's current allocated size, or n
+ * is less than or equal to p's size). This may be used instead of
+ * plain realloc if an alternative allocation strategy is needed
+ * upon failure to expand space, for example, reallocation of a
+ * buffer that must be memory-aligned or cleared. You can use
+ * realloc_in_place to trigger these alternatives only when needed.
+ *
+ * @param p is address of current allocation
+ * @param n is number of bytes needed
+ * @return rax is result, or NULL w/ errno
+ * @see dlrealloc_in_place()
+ * @threadsafe
+ */
+void *realloc_in_place(void *p, size_t n) {
+  return hook_realloc_in_place(p, n);
+}