base/allocator/allocator_interception_mac.h

// Copyright 2017 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef BASE_ALLOCATOR_ALLOCATOR_INTERCEPTION_MAC_H_
#define BASE_ALLOCATOR_ALLOCATOR_INTERCEPTION_MAC_H_

#include <malloc/malloc.h>
#include <stddef.h>

#include "base/base_export.h"
#include "third_party/apple_apsl/malloc.h"

namespace base {
namespace allocator {

typedef void* (*malloc_type)(struct _malloc_zone_t* zone, size_t size);
typedef void* (*calloc_type)(struct _malloc_zone_t* zone,
                             size_t num_items,
                             size_t size);
typedef void* (*valloc_type)(struct _malloc_zone_t* zone, size_t size);
typedef void (*free_type)(struct _malloc_zone_t* zone, void* ptr);
typedef void* (*realloc_type)(struct _malloc_zone_t* zone,
                              void* ptr,
                              size_t size);
typedef void* (*memalign_type)(struct _malloc_zone_t* zone,
                               size_t alignment,
                               size_t size);
typedef unsigned (*batch_malloc_type)(struct _malloc_zone_t* zone,
                                      size_t size,
                                      void** results,
                                      unsigned num_requested);
typedef void (*batch_free_type)(struct _malloc_zone_t* zone,
                                void** to_be_freed,
                                unsigned num_to_be_freed);
typedef void (*free_definite_size_type)(struct _malloc_zone_t* zone,
                                        void* ptr,
                                        size_t size);
typedef size_t (*size_fn_type)(struct _malloc_zone_t* zone, const void* ptr);

struct MallocZoneFunctions {
  MallocZoneFunctions();
  malloc_type malloc = nullptr;
  calloc_type calloc = nullptr;
  valloc_type valloc = nullptr;
  free_type free = nullptr;
  realloc_type realloc = nullptr;
  memalign_type memalign = nullptr;
  batch_malloc_type batch_malloc = nullptr;
  batch_free_type batch_free = nullptr;
  free_definite_size_type free_definite_size = nullptr;
  size_fn_type size = nullptr;
};

// Saves the function pointers currently used by default zone into |functions|.
void StoreFunctionsForDefaultZone(MallocZoneFunctions* functions);

// Updates the default malloc zone to use the functions specified by
// |functions|.
void ReplaceFunctionsForDefaultZone(const MallocZoneFunctions* functions);

extern bool g_replaced_default_zone;

// Calls the original implementation of malloc/calloc prior to interception.
bool UncheckedMallocMac(size_t size, void** result);
bool UncheckedCallocMac(size_t num_items, size_t size, void** result);

// Intercepts calls to default and purgeable malloc zones. Intercepts Core
// Foundation and Objective-C allocations.
// Has no effect on the default malloc zone if the allocator shim already
// performs that interception.
BASE_EXPORT void InterceptAllocationsMac();
}  // namespace allocator
}  // namespace base

#endif  // BASE_ALLOCATOR_ALLOCATOR_INTERCEPTION_MAC_H_