snmp_threadsync.h

00001 /**
00002  * @file
00003  * SNMP server MIB API to implement thread synchronization
00004  */
00005 
00006 /*
00007  * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
00008  * All rights reserved.
00009  *
00010  * Redistribution and use in source and binary forms, with or without modification,
00011  * are permitted provided that the following conditions are met:
00012  *
00013  * 1. Redistributions of source code must retain the above copyright notice,
00014  *    this list of conditions and the following disclaimer.
00015  * 2. Redistributions in binary form must reproduce the above copyright notice,
00016  *    this list of conditions and the following disclaimer in the documentation
00017  *    and/or other materials provided with the distribution.
00018  * 3. The name of the author may not be used to endorse or promote products
00019  *    derived from this software without specific prior written permission.
00020  *
00021  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
00022  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
00023  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
00024  * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
00025  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
00026  * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
00027  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
00028  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
00029  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
00030  * OF SUCH DAMAGE.
00031  *
00032  * This file is part of the lwIP TCP/IP stack.
00033  *
00034  * Author: Dirk Ziegelmeier <dziegel@gmx.de>
00035  *
00036  */
00037 
00038 #ifndef LWIP_HDR_APPS_SNMP_THREADSYNC_H
00039 #define LWIP_HDR_APPS_SNMP_THREADSYNC_H
00040 
00041 #include "lwip/apps/snmp_opts.h"
00042 
00043 #ifdef __cplusplus
00044 extern "C" {
00045 #endif
00046 
00047 #if LWIP_SNMP /* don't build if not configured for use in lwipopts.h */
00048 
00049 #include "lwip/apps/snmp_core.h"
00050 #include "lwip/sys.h"
00051 
00052 typedef void (*snmp_threadsync_called_fn)(void* arg);
00053 typedef void (*snmp_threadsync_synchronizer_fn)(snmp_threadsync_called_fn fn, void* arg);
00054 
00055 
00056 /** Thread sync runtime data. For internal usage only. */
00057 struct threadsync_data
00058 {
00059   union {
00060     snmp_err_t err;
00061     s16_t s16;
00062   } retval;
00063   union {
00064     const u32_t *root_oid;
00065     void *value;
00066   } arg1;
00067   union {
00068     u8_t root_oid_len;
00069     u16_t len;
00070   } arg2;
00071   const struct snmp_threadsync_node *threadsync_node;
00072   struct snmp_node_instance proxy_instance;
00073 };
00074 
00075 /** Thread sync instance. Needed EXCATLY once for every thread to be synced into. */
00076 struct snmp_threadsync_instance
00077 {
00078   sys_sem_t                       sem;
00079   sys_mutex_t                     sem_usage_mutex;
00080   snmp_threadsync_synchronizer_fn sync_fn;
00081   struct threadsync_data          data;
00082 };
00083 
00084 /** SNMP thread sync proxy leaf node */
00085 struct snmp_threadsync_node
00086 {
00087   /* inherited "base class" members */
00088   struct snmp_leaf_node           node;
00089 
00090   const struct snmp_leaf_node     *target;
00091   struct snmp_threadsync_instance *instance;
00092 };
00093 
00094 snmp_err_t snmp_threadsync_get_instance(const u32_t *root_oid, u8_t root_oid_len, struct snmp_node_instance* instance);
00095 snmp_err_t snmp_threadsync_get_next_instance(const u32_t *root_oid, u8_t root_oid_len, struct snmp_node_instance* instance);
00096 
00097 /** Create thread sync proxy node */
00098 #define SNMP_CREATE_THREAD_SYNC_NODE(oid, target_leaf_node, threadsync_instance) \
00099   {{{ SNMP_NODE_THREADSYNC, (oid) }, \
00100     snmp_threadsync_get_instance, \
00101     snmp_threadsync_get_next_instance }, \
00102     (target_leaf_node), \
00103     (threadsync_instance) }
00104 
00105 /** Create thread sync instance data */
00106 void snmp_threadsync_init(struct snmp_threadsync_instance *instance, snmp_threadsync_synchronizer_fn sync_fn);
00107 
00108 #endif /* LWIP_SNMP */
00109 
00110 #ifdef __cplusplus
00111 }
00112 #endif
00113 
00114 #endif /* LWIP_HDR_APPS_SNMP_THREADSYNC_H */