1 /*
2 ** Zabbix
3 ** Copyright (C) 2001-2021 Zabbix SIA
4 **
5 ** This program is free software; you can redistribute it and/or modify
6 ** it under the terms of the GNU General Public License as published by
7 ** the Free Software Foundation; either version 2 of the License, or
8 ** (at your option) any later version.
9 **
10 ** This program is distributed in the hope that it will be useful,
11 ** but WITHOUT ANY WARRANTY; without even the implied warranty of
12 ** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 ** GNU General Public License for more details.
14 **
15 ** You should have received a copy of the GNU General Public License
16 ** along with this program; if not, write to the Free Software
17 ** Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
18 **/
19 
20 #ifndef ZABBIX_IPC_H
21 #define ZABBIX_IPC_H
22 
23 #if defined(_WINDOWS)
24 #	error "This module allowed only for Unix OS"
25 #endif
26 
27 #include "mutexs.h"
28 
29 #define ZBX_NONEXISTENT_SHMID		(-1)
30 
31 #define ZBX_IPC_CONFIG_ID		'g'
32 #define ZBX_IPC_HISTORY_ID		'h'
33 #define ZBX_IPC_HISTORY_INDEX_ID	'H'
34 #define ZBX_IPC_TREND_ID		't'
35 #define ZBX_IPC_STRPOOL_ID		's'
36 #define ZBX_IPC_COLLECTOR_ID		'l'
37 #define ZBX_IPC_COLLECTOR_DISKSTAT	'm'
38 #define ZBX_IPC_SELFMON_ID		'S'
39 #define ZBX_IPC_VALUECACHE_ID		'v'
40 #define ZBX_IPC_VMWARE_ID		'w'
41 #define ZBX_IPC_COLLECTOR_PROC_ID	'p'
42 
43 key_t	zbx_ftok(char *path, int id);
44 int	zbx_shmget(key_t key, size_t size);
45 
46 /* data copying callback function prototype */
47 typedef void (*zbx_shm_copy_func_t)(void *dst, size_t size_dst, const void *src);
48 
49 /* dynamic shared memory data structure */
50 typedef struct
51 {
52 	/* shared memory segment identifier */
53 	int			shmid;
54 
55 	/* project id used to generate shared memory key */
56 	int			proj_id;
57 
58 	/* allocated size */
59 	size_t			size;
60 
61 	/* callback function to copy data after shared memory reallocation */
62 	zbx_shm_copy_func_t	copy_func;
63 
64 	ZBX_MUTEX		lock;
65 }
66 zbx_dshm_t;
67 
68 /* local process reference to dynamic shared memory data */
69 typedef struct
70 {
71 	/* shared memory segment identifier */
72 	int	shmid;
73 
74 	/* shared memory base address */
75 	void	*addr;
76 }
77 zbx_dshm_ref_t;
78 
79 int	zbx_dshm_create(zbx_dshm_t *shm, int proj_id, size_t shm_size, ZBX_MUTEX_NAME mutex,
80 		zbx_shm_copy_func_t copy_func, char **errmsg);
81 
82 int	zbx_dshm_destroy(zbx_dshm_t *shm, char **errmsg);
83 
84 int	zbx_dshm_realloc(zbx_dshm_t *shm, size_t size, char **errmsg);
85 
86 int	zbx_dshm_validate_ref(const zbx_dshm_t *shm, zbx_dshm_ref_t *shm_ref, char **errmsg);
87 
88 void	zbx_dshm_lock(zbx_dshm_t *shm);
89 void	zbx_dshm_unlock(zbx_dshm_t *shm);
90 
91 #endif
92