service_mysql_alloc.h

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/* Copyright (c) 2012, 2017, Oracle and/or its affiliates. All rights reserved.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License, version 2.0,
   as published by the Free Software Foundation.

   This program is also distributed with certain software (including
   but not limited to OpenSSL) that is licensed under separate terms,
   as designated in a particular file or component or in included license
   documentation.  The authors of MySQL hereby grant you an additional
   permission to link the program and your derivative works with the
   separately licensed software that they have included with MySQL.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License, version 2.0, for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA */

#ifndef MYSQL_SERVICE_MYSQL_ALLOC_INCLUDED
#define MYSQL_SERVICE_MYSQL_ALLOC_INCLUDED

/**
  @file include/mysql/service_mysql_alloc.h
*/

#ifndef MYSQL_ABI_CHECK
#include <stdlib.h>
#endif

/* PSI_memory_key */
#include "mysql/components/services/psi_memory_bits.h"

/* myf */
typedef int myf_t;

typedef void *(*mysql_malloc_t)(PSI_memory_key key, size_t size, myf_t flags);
typedef void *(*mysql_realloc_t)(PSI_memory_key key, void *ptr, size_t size,
                                 myf_t flags);
typedef void (*mysql_claim_t)(const void *ptr);
typedef void (*mysql_free_t)(void *ptr);
typedef void *(*my_memdup_t)(PSI_memory_key key, const void *from,
                             size_t length, myf_t flags);
typedef char *(*my_strdup_t)(PSI_memory_key key, const char *from, myf_t flags);
typedef char *(*my_strndup_t)(PSI_memory_key key, const char *from,
                              size_t length, myf_t flags);

/**
  @ingroup group_ext_plugin_services

  This service allows plugins to allocate and free memory through the server's
  memory handling routines.
  This allows uniform memory handling and instrumentation.
*/
struct mysql_malloc_service_st {
  /**
    Allocates a block of memory

    @sa my_malloc
  */
  mysql_malloc_t mysql_malloc;
  /**
    Reallocates a block of memory

    @sa my_realloc
  */
  mysql_realloc_t mysql_realloc;
  /**
    Re-instruments a block of memory

    @sa my_claim
  */
  mysql_claim_t mysql_claim;
  /**
    Frees a block of memory

    @sa my_free
  */
  mysql_free_t mysql_free;
  /**
    Copies a buffer into a new buffer

    @sa my_memdup
  */
  my_memdup_t my_memdup;
  /**
    Copies a string into a new buffer

    @sa my_strdup
  */
  my_strdup_t my_strdup;
  /**
    Copies no more than n characters of a string into a new buffer

    @sa my_strndup
  */
  my_strndup_t my_strndup;
};

extern "C" struct mysql_malloc_service_st *mysql_malloc_service;

#ifdef MYSQL_DYNAMIC_PLUGIN

#define my_malloc mysql_malloc_service->mysql_malloc
#define my_realloc mysql_malloc_service->mysql_realloc
#define my_claim mysql_malloc_service->mysql_claim
#define my_free mysql_malloc_service->mysql_free
#define my_memdup mysql_malloc_service->my_memdup
#define my_strdup mysql_malloc_service->my_strdup
#define my_strndup mysql_malloc_service->my_strndup

#else

extern void *my_malloc(PSI_memory_key key, size_t size, myf_t flags);
extern void *my_realloc(PSI_memory_key key, void *ptr, size_t size,
                        myf_t flags);
extern void my_claim(const void *ptr);
extern void my_free(void *ptr);
extern void *my_memdup(PSI_memory_key key, const void *from, size_t length,
                       myf_t flags);
extern char *my_strdup(PSI_memory_key key, const char *from, myf_t flags);
extern char *my_strndup(PSI_memory_key key, const char *from, size_t length,
                        myf_t flags);

#endif

#endif