freebsd-skq/contrib/bsnmp/lib/snmpclient.h
Edward Tomasz Napierala f53120073b Revert "bsnmpclient(3): make it thread-safe"
This reverts commit 89e3d5671b.

As pointed out, there are several problems with that commit:

1. The new semantics, while useful for clients where multiple
   threads use separate contexts, breaks clients which correctly
   share a single one
2. Change in semantics would require a library version bump
3. It doesn't build with GCC
2020-12-29 19:55:05 +00:00

203 lines
6.2 KiB
C

/*
* Copyright (c) 2001-2003
* Fraunhofer Institute for Open Communication Systems (FhG Fokus).
* All rights reserved.
*
* Author: Harti Brandt <harti@freebsd.org>
* Kendy Kutzner
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $Begemot: bsnmp/lib/snmpclient.h,v 1.19 2005/05/23 11:10:14 brandt_h Exp $
*/
#ifndef _BSNMP_SNMPCLIENT_H
#define _BSNMP_SNMPCLIENT_H
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <netinet/in.h>
#include <stddef.h>
#define SNMP_STRERROR_LEN 200
#define SNMP_LOCAL_PATH "/tmp/snmpXXXXXXXXXXXXXX"
/*
* transport methods
*/
#define SNMP_TRANS_UDP 0
#define SNMP_TRANS_LOC_DGRAM 1
#define SNMP_TRANS_LOC_STREAM 2
#define SNMP_TRANS_UDP6 3
/* type of callback function for responses
* this callback function is responsible for free() any memory associated with
* any of the PDUs. Therefor it may call snmp_pdu_free() */
typedef void (*snmp_send_cb_f)(struct snmp_pdu *, struct snmp_pdu *, void *);
/* type of callback function for timeouts */
typedef void (*snmp_timeout_cb_f)(void * );
/* timeout start function */
typedef void *(*snmp_timeout_start_f)(struct timeval *timeout,
snmp_timeout_cb_f callback, void *);
/* timeout stop function */
typedef void (*snmp_timeout_stop_f)(void *timeout_id);
/*
* Client context.
*/
struct snmp_client {
enum snmp_version version;
int trans; /* which transport to use */
/* these two are read-only for the application */
char *cport; /* port number as string */
char *chost; /* host name or IP address as string */
char read_community[SNMP_COMMUNITY_MAXLEN + 1];
char write_community[SNMP_COMMUNITY_MAXLEN + 1];
/* SNMPv3 specific fields */
int32_t identifier;
int32_t security_model;
struct snmp_engine engine;
struct snmp_user user;
/* SNMPv3 Access control - VACM*/
uint32_t clen;
uint8_t cengine[SNMP_ENGINE_ID_SIZ];
char cname[SNMP_CONTEXT_NAME_SIZ];
struct timeval timeout;
u_int retries;
int dump_pdus;
size_t txbuflen;
size_t rxbuflen;
int fd;
int32_t next_reqid;
int32_t max_reqid;
int32_t min_reqid;
char error[SNMP_STRERROR_LEN];
snmp_timeout_start_f timeout_start;
snmp_timeout_stop_f timeout_stop;
char local_path[sizeof(SNMP_LOCAL_PATH)];
};
/* the global context */
extern struct snmp_client snmp_client;
/* initizialies a snmp_client structure */
void snmp_client_init(struct snmp_client *);
/* initialize fields */
int snmp_client_set_host(struct snmp_client *, const char *);
int snmp_client_set_port(struct snmp_client *, const char *);
/* open connection to snmp server (hostname or portname can be NULL) */
int snmp_open(const char *_hostname, const char *_portname,
const char *_read_community, const char *_write_community);
/* close connection */
void snmp_close(void);
/* initialize a snmp_pdu structure */
void snmp_pdu_create(struct snmp_pdu *, u_int _op);
/* add pairs of (struct asn_oid *, enum snmp_syntax) to an existing pdu */
int snmp_add_binding(struct snmp_pdu *, ...);
/* check wheater the answer is valid or not */
int snmp_pdu_check(const struct snmp_pdu *_req, const struct snmp_pdu *_resp);
int32_t snmp_pdu_send(struct snmp_pdu *_pdu, snmp_send_cb_f _func, void *_arg);
/* append an index to an oid */
int snmp_oid_append(struct asn_oid *_oid, const char *_fmt, ...);
/* receive a packet */
int snmp_receive(int _blocking);
/*
* This structure is used to describe an SNMP table that is to be fetched.
* The C-structure that is produced by the fetch function must start with
* a TAILQ_ENTRY and an u_int64_t.
*/
struct snmp_table {
/* base OID of the table */
struct asn_oid table;
/* type OID of the LastChange variable for the table if any */
struct asn_oid last_change;
/* maximum number of iterations if table has changed */
u_int max_iter;
/* size of the C-structure */
size_t entry_size;
/* number of index fields */
u_int index_size;
/* bit mask of required fields */
uint64_t req_mask;
/* indexes and columns to fetch. Ended by a NULL syntax entry */
struct snmp_table_entry {
/* the column sub-oid, ignored for index fields */
asn_subid_t subid;
/* the syntax of the column or index */
enum snmp_syntax syntax;
/* offset of the field into the C-structure. For octet strings
* this points to an u_char * followed by a size_t */
off_t offset;
#if defined(__GNUC__) && __GNUC__ < 3
} entries[0];
#else
} entries[];
#endif
};
/* callback type for table fetch */
typedef void (*snmp_table_cb_f)(void *_list, void *_arg, int _res);
/* fetch a table. The argument points to a TAILQ_HEAD */
int snmp_table_fetch(const struct snmp_table *descr, void *);
int snmp_table_fetch_async(const struct snmp_table *, void *,
snmp_table_cb_f, void *);
/* send a request and wait for the response */
int snmp_dialog(struct snmp_pdu *_req, struct snmp_pdu *_resp);
/* discover an authorative snmpEngineId */
int snmp_discover_engine(char *);
/* parse a server specification */
int snmp_parse_server(struct snmp_client *, const char *);
#endif /* _BSNMP_SNMPCLIENT_H */