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src/frozen_malloc.c libmalloc-792.1.1 /dev/null
--- libmalloc/libmalloc-792.1.1/src/frozen_malloc.c
+++ /dev/null
@@ -1,178 +0,0 @@
-/*
- * Copyright (c) 2015 Apple Inc. All rights reserved.
- *
- * @APPLE_LICENSE_HEADER_START@
- *
- * This file contains Original Code and/or Modifications of Original Code
- * as defined in and that are subject to the Apple Public Source License
- * Version 2.0 (the 'License'). You may not use this file except in
- * compliance with the License. Please obtain a copy of the License at
- * http://www.opensource.apple.com/apsl/ and read it before using this
- * file.
- *
- * The Original Code and all software distributed under the License are
- * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
- * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
- * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
- * Please see the License for the specific language governing rights and
- * limitations under the License.
- *
- * @APPLE_LICENSE_HEADER_END@
- */
-
-#include "internal.h"
-
-/********* Support code for emacs unexec ************/
-
-/* History of freezedry version numbers:
- *
- * 1) Old malloc (before the scalable malloc implementation in this file
- *    existed).
- * 2) Original freezedrying code for scalable malloc.  This code was apparently
- *    based on the old freezedrying code and was fundamentally flawed in its
- *    assumption that tracking allocated memory regions was adequate to fake
- *    operations on freezedried memory.  This doesn't work, since scalable
- *    malloc does not store flags in front of large page-aligned allocations.
- * 3) Original szone-based freezedrying code.
- * 4) Fresher malloc with tiny zone
- * 5) 32/64bit compatible malloc
- * 6) Metadata within 1MB and 8MB region for tiny and small
- *
- * No version backward compatibility is provided, but the version number does
- * make it possible for malloc_jumpstart() to return an error if the application
- * was freezedried with an older version of malloc.
- */
-#define MALLOC_FREEZEDRY_VERSION 6
-
-typedef struct {
-	unsigned version;
-	unsigned nszones;
-	szone_t *szones;
-} malloc_frozen;
-
-static void *
-frozen_malloc(szone_t *zone, size_t new_size)
-{
-	return malloc(new_size);
-}
-
-static void *
-frozen_calloc(szone_t *zone, size_t num_items, size_t size)
-{
-	return calloc(num_items, size);
-}
-
-static void *
-frozen_valloc(szone_t *zone, size_t new_size)
-{
-	return valloc(new_size);
-}
-
-static void *
-frozen_realloc(szone_t *zone, void *ptr, size_t new_size)
-{
-	size_t old_size = szone_size(zone, ptr);
-	void *new_ptr;
-
-	if (new_size <= old_size) {
-		return ptr;
-	}
-	new_ptr = malloc(new_size);
-	if (old_size > 0) {
-		memcpy(new_ptr, ptr, old_size);
-	}
-	return new_ptr;
-}
-
-static void
-frozen_free(szone_t *zone, void *ptr)
-{
-}
-
-static void
-frozen_destroy(szone_t *zone)
-{
-}
-
-/********* Pseudo-private API for emacs unexec ************/
-
-/*
- * malloc_freezedry() records all of the szones in use, so that they can be
- * partially reconstituted by malloc_jumpstart().  Due to the differences
- * between reconstituted memory regions and those created by the szone code,
- * care is taken not to reallocate from the freezedried memory, except in the
- * case of a non-growing realloc().
- *
- * Due to the flexibility provided by the zone registration mechanism, it is
- * impossible to implement generic freezedrying for any zone type.  This code
- * only handles applications that use the szone allocator, so malloc_freezedry()
- * returns 0 (error) if any non-szone zones are encountered.
- */
-
-uintptr_t
-malloc_freezedry(void)
-{
-	extern unsigned malloc_num_zones;
-	extern malloc_zone_t **malloc_zones;
-	malloc_frozen *data;
-	unsigned i;
-
-	/* Allocate space in which to store the freezedry state. */
-	data = (malloc_frozen *)malloc(sizeof(malloc_frozen));
-
-	/* Set freezedry version number so that malloc_jumpstart() can check for compatibility. */
-	data->version = MALLOC_FREEZEDRY_VERSION;
-
-	/* Allocate the array of szone pointers. */
-	data->nszones = malloc_num_zones;
-	data->szones = (szone_t *)calloc(malloc_num_zones, sizeof(szone_t));
-
-	/*
-	 * Fill in the array of szone structures.  They are copied rather than
-	 * referenced, since the originals are likely to be clobbered during malloc
-	 * initialization.
-	 */
-	for (i = 0; i < malloc_num_zones; i++) {
-		if (strcmp(malloc_zones[i]->zone_name, "DefaultMallocZone")) {
-			/* Unknown zone type. */
-			_free(data->szones);
-			_free(data);
-			return 0;
-		}
-		memcpy(&data->szones[i], malloc_zones[i], sizeof(szone_t));
-	}
-
-	return ((uintptr_t)data);
-}
-
-int
-malloc_jumpstart(uintptr_t cookie)
-{
-	malloc_frozen *data = (malloc_frozen *)cookie;
-	unsigned i;
-
-	if (data->version != MALLOC_FREEZEDRY_VERSION) {
-		/* Unsupported freezedry version. */
-		return 1;
-	}
-
-	for (i = 0; i < data->nszones; i++) {
-		/* Set function pointers.  Even the functions that stay the same must be
-		 * set, since there are no guarantees that they will be mapped to the
-		 * same addresses. */
-		data->szones[i].basic_zone.size = (void *)szone_size;
-		data->szones[i].basic_zone.malloc = (void *)frozen_malloc;
-		data->szones[i].basic_zone.calloc = (void *)frozen_calloc;
-		data->szones[i].basic_zone.valloc = (void *)frozen_valloc;
-		data->szones[i].basic_zone.free = (void *)frozen_free;
-		data->szones[i].basic_zone.realloc = (void *)frozen_realloc;
-		data->szones[i].basic_zone.destroy = (void *)frozen_destroy;
-		data->szones[i].basic_zone.introspect = (struct malloc_introspection_t *)&szone_introspect;
-
-		/* Register the freezedried zone. */
-		malloc_zone_register(&data->szones[i].basic_zone);
-	}
-
-	return 0;
-}