Zabbix

/*

** Copyright (C) 2001-2025 Zabbix SIA

**

** This program is free software: you can redistribute it and/or modify it under the terms of

** the GNU Affero General Public License as published by the Free Software Foundation, version 3.

**

** 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 Affero General Public License for more details.

**

** You should have received a copy of the GNU Affero General Public License along with this program.

** If not, see <https://www.gnu.org/licenses/>.

**/

​

#ifndef ZABBIX_SHMEM_H

#define ZABBIX_SHMEM_H

​

#include "zbxnix.h"

​

#define SHMEM_MIN_ALLOC 24      /* should be a multiple of 8 and at least (2 * ZBX_PTR_SIZE) */

​

#define ZBX_SHMEM_MIN_BUCKET_SIZE   SHMEM_MIN_ALLOC

#define SHMEM_MAX_BUCKET_SIZE       256 /* starting from this size all free chunks are put into the same bucket */

#define ZBX_SHMEM_BUCKET_COUNT      ((SHMEM_MAX_BUCKET_SIZE - ZBX_SHMEM_MIN_BUCKET_SIZE) / 8 + 1)

​

typedef struct

{

    void        *base;

    void        **buckets;

    void        *lo_bound;

    void        *hi_bound;

    zbx_uint64_t    free_size;

    zbx_uint64_t    used_size;

    zbx_uint64_t    orig_size;

    zbx_uint64_t    total_size;

    int     shm_id;

​

    /* Continue execution in out of memory situation.                         */

    /* Normally allocator forces exit when it runs out of allocatable memory. */

    /* Set this flag to 1 to allow execution in out of memory situations.     */

    char        allow_oom;

​

    const char  *mem_descr;

    const char  *mem_param;

}

zbx_shmem_info_t;

​

typedef struct

{

    zbx_uint64_t    free_size;

    zbx_uint64_t    used_size;

    zbx_uint64_t    min_chunk_size;

    zbx_uint64_t    max_chunk_size;

    zbx_uint64_t    overhead;

    unsigned int    chunks_num[ZBX_SHMEM_BUCKET_COUNT];

    unsigned int    free_chunks;

    unsigned int    used_chunks;

}

zbx_shmem_stats_t;

​

int zbx_shmem_create(zbx_shmem_info_t **info, zbx_uint64_t size, const char *descr, const char *param,

        int allow_oom, char **error);

int zbx_shmem_create_min(zbx_shmem_info_t **info, zbx_uint64_t size, const char *descr, const char *param,