3 * MIB tree access/construction functions.
7 * Copyright (c) 2006 Axon Digital Design B.V., The Netherlands.
10 * Redistribution and use in source and binary forms, with or without modification,
11 * are permitted provided that the following conditions are met:
13 * 1. Redistributions of source code must retain the above copyright notice,
14 * this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright notice,
16 * this list of conditions and the following disclaimer in the documentation
17 * and/or other materials provided with the distribution.
18 * 3. The name of the author may not be used to endorse or promote products
19 * derived from this software without specific prior written permission.
21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
22 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
23 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
24 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
25 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
26 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
29 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
32 * Author: Christiaan Simons <christiaan.simons@axon.tv>
37 #if LWIP_SNMP /* don't build if not configured for use in lwipopts.h */
39 #include "lwip/snmp_structs.h"
42 /** .iso.org.dod.internet address prefix, @see snmp_iso_*() */
43 const s32_t prefix
[4] = {1, 3, 6, 1};
45 #define NODE_STACK_SIZE (LWIP_SNMP_OBJ_ID_LEN)
46 /** node stack entry (old news?) */
50 struct mib_node
* r_ptr
;
51 /** right child identifier */
53 /** right child next level */
56 static u8_t node_stack_cnt
;
57 static struct nse node_stack
[NODE_STACK_SIZE
];
60 * Pushes nse struct onto stack.
63 push_node(struct nse
* node
)
65 LWIP_ASSERT("node_stack_cnt < NODE_STACK_SIZE",node_stack_cnt
< NODE_STACK_SIZE
);
66 LWIP_DEBUGF(SNMP_MIB_DEBUG
,("push_node() node=%p id=%"S32_F
"\n",(void*)(node
->r_ptr
),node
->r_id
));
67 if (node_stack_cnt
< NODE_STACK_SIZE
)
69 node_stack
[node_stack_cnt
] = *node
;
75 * Pops nse struct from stack.
78 pop_node(struct nse
* node
)
80 if (node_stack_cnt
> 0)
83 *node
= node_stack
[node_stack_cnt
];
85 LWIP_DEBUGF(SNMP_MIB_DEBUG
,("pop_node() node=%p id=%"S32_F
"\n",(void *)(node
->r_ptr
),node
->r_id
));
89 * Conversion from ifIndex to lwIP netif
90 * @param ifindex is a s32_t object sub-identifier
91 * @param netif points to returned netif struct pointer
94 snmp_ifindextonetif(s32_t ifindex
, struct netif
**netif
)
96 struct netif
*nif
= netif_list
;
101 while ((nif
!= NULL
) && (i
< ifidx
))
110 * Conversion from lwIP netif to ifIndex
111 * @param netif points to a netif struct
112 * @param ifidx points to s32_t object sub-identifier
115 snmp_netiftoifindex(struct netif
*netif
, s32_t
*ifidx
)
117 struct netif
*nif
= netif_list
;
130 * Conversion from oid to lwIP ip_addr
131 * @param ident points to s32_t ident[4] input
132 * @param ip points to output struct
135 snmp_oidtoip(s32_t
*ident
, struct ip_addr
*ip
)
150 * Conversion from lwIP ip_addr to oid
151 * @param ip points to input struct
152 * @param ident points to s32_t ident[4] output
155 snmp_iptooid(struct ip_addr
*ip
, s32_t
*ident
)
160 ident
[0] = (ipa
>> 24) & 0xff;
161 ident
[1] = (ipa
>> 16) & 0xff;
162 ident
[2] = (ipa
>> 8) & 0xff;
163 ident
[3] = ipa
& 0xff;
166 struct mib_list_node
*
167 snmp_mib_ln_alloc(s32_t id
)
169 struct mib_list_node
*ln
;
171 ln
= (struct mib_list_node
*)mem_malloc(sizeof(struct mib_list_node
));
183 snmp_mib_ln_free(struct mib_list_node
*ln
)
188 struct mib_list_rootnode
*
189 snmp_mib_lrn_alloc(void)
191 struct mib_list_rootnode
*lrn
;
193 lrn
= (struct mib_list_rootnode
*)mem_malloc(sizeof(struct mib_list_rootnode
));
196 lrn
->get_object_def
= noleafs_get_object_def
;
197 lrn
->get_value
= noleafs_get_value
;
198 lrn
->set_test
= noleafs_set_test
;
199 lrn
->set_value
= noleafs_set_value
;
200 lrn
->node_type
= MIB_NODE_LR
;
210 snmp_mib_lrn_free(struct mib_list_rootnode
*lrn
)
216 * Inserts node in idx list in a sorted
217 * (ascending order) fashion and
218 * allocates the node if needed.
220 * @param rn points to the root node
221 * @param objid is the object sub identifier
222 * @param insn points to a pointer to the inserted node
223 * used for constructing the tree.
224 * @return -1 if failed, 1 if inserted, 2 if present.
227 snmp_mib_node_insert(struct mib_list_rootnode
*rn
, s32_t objid
, struct mib_list_node
**insn
)
229 struct mib_list_node
*nn
;
232 LWIP_ASSERT("rn != NULL",rn
!= NULL
);
234 /* -1 = malloc failure, 0 = not inserted, 1 = inserted, 2 = was present */
236 if (rn
->head
== NULL
)
238 /* empty list, add first node */
239 LWIP_DEBUGF(SNMP_MIB_DEBUG
,("alloc empty list objid==%"S32_F
"\n",objid
));
240 nn
= snmp_mib_ln_alloc(objid
);
255 struct mib_list_node
*n
;
256 /* at least one node is present */
258 while ((n
!= NULL
) && (insert
== 0))
260 if (n
->objid
== objid
)
262 /* node is already there */
263 LWIP_DEBUGF(SNMP_MIB_DEBUG
,("node already there objid==%"S32_F
"\n",objid
));
267 else if (n
->objid
< objid
)
271 /* alloc and insert at the tail */
272 LWIP_DEBUGF(SNMP_MIB_DEBUG
,("alloc ins tail objid==%"S32_F
"\n",objid
));
273 nn
= snmp_mib_ln_alloc(objid
);
285 /* insertion failure */
291 /* there's more to explore: traverse list */
292 LWIP_DEBUGF(SNMP_MIB_DEBUG
,("traverse list\n"));
298 /* n->objid > objid */
299 /* alloc and insert between n->prev and n */
300 LWIP_DEBUGF(SNMP_MIB_DEBUG
,("alloc ins n->prev, objid==%"S32_F
", n\n",objid
));
301 nn
= snmp_mib_ln_alloc(objid
);
306 /* insert at the head */
314 /* insert in the middle */
325 /* insertion failure */
335 LWIP_ASSERT("insert != 0",insert
!= 0);
340 * Finds node in idx list and returns deletion mark.
342 * @param rn points to the root node
343 * @param objid is the object sub identifier
344 * @param fn returns pointer to found node
345 * @return 0 if not found, 1 if deletable,
346 * 2 can't delete (2 or more children), 3 not a list_node
349 snmp_mib_node_find(struct mib_list_rootnode
*rn
, s32_t objid
, struct mib_list_node
**fn
)
352 struct mib_list_node
*n
;
354 LWIP_ASSERT("rn != NULL",rn
!= NULL
);
356 while ((n
!= NULL
) && (n
->objid
!= objid
))
364 else if (n
->nptr
== NULL
)
366 /* leaf, can delete node */
371 struct mib_list_rootnode
*r
;
373 if (n
->nptr
->node_type
== MIB_NODE_LR
)
375 r
= (struct mib_list_rootnode
*)n
->nptr
;
378 /* can't delete node */
383 /* count <= 1, can delete node */
389 /* other node type */
398 * Removes node from idx list
399 * if it has a single child left.
401 * @param rn points to the root node
402 * @param n points to the node to delete
403 * @return the nptr to be freed by caller
405 struct mib_list_rootnode
*
406 snmp_mib_node_delete(struct mib_list_rootnode
*rn
, struct mib_list_node
*n
)
408 struct mib_list_rootnode
*next
;
410 LWIP_ASSERT("rn != NULL",rn
!= NULL
);
411 LWIP_ASSERT("n != NULL",n
!= NULL
);
413 /* caller must remove this sub-tree */
414 next
= (struct mib_list_rootnode
*)(n
->nptr
);
422 /* not last node, new list begin */
423 n
->next
->prev
= NULL
;
426 else if (n
== rn
->tail
)
431 /* not last node, new list end */
432 n
->prev
->next
= NULL
;
437 /* node must be in the middle */
438 n
->prev
->next
= n
->next
;
439 n
->next
->prev
= n
->prev
;
441 LWIP_DEBUGF(SNMP_MIB_DEBUG
,("free list objid==%"S32_F
"\n",n
->objid
));
454 * Searches tree for the supplied (scalar?) object identifier.
456 * @param node points to the root of the tree ('.internet')
457 * @param ident_len the length of the supplied object identifier
458 * @param ident points to the array of sub identifiers
459 * @param np points to the found object instance (rerurn)
460 * @return pointer to the requested parent (!) node if success, NULL otherwise
463 snmp_search_tree(struct mib_node
*node
, u8_t ident_len
, s32_t
*ident
, struct snmp_name_ptr
*np
)
465 u8_t node_type
, ext_level
;
468 LWIP_DEBUGF(SNMP_MIB_DEBUG
,("node==%p *ident==%"S32_F
"\n",(void*)node
,*ident
));
471 node_type
= node
->node_type
;
472 if ((node_type
== MIB_NODE_AR
) || (node_type
== MIB_NODE_RA
))
474 struct mib_array_node
*an
;
479 /* array node (internal ROM or RAM, fixed length) */
480 an
= (struct mib_array_node
*)node
;
482 while ((i
< an
->maxlength
) && (an
->objid
[i
] != *ident
))
486 if (i
< an
->maxlength
)
488 /* found it, if available proceed to child, otherwise inspect leaf */
489 LWIP_DEBUGF(SNMP_MIB_DEBUG
,("an->objid[%"U16_F
"]==%"S32_F
" *ident==%"S32_F
"\n",i
,an
->objid
[i
],*ident
));
490 if (an
->nptr
[i
] == NULL
)
492 /* a scalar leaf OR table,
493 inspect remaining instance number / table index */
494 np
->ident_len
= ident_len
;
496 return (struct mib_node
*)an
;
500 /* follow next child pointer */
508 /* search failed, identifier mismatch (nosuchname) */
509 LWIP_DEBUGF(SNMP_MIB_DEBUG
,("an search failed *ident==%"S32_F
"\n",*ident
));
515 /* search failed, short object identifier (nosuchname) */
516 LWIP_DEBUGF(SNMP_MIB_DEBUG
,("an search failed, short object identifier\n"));
520 else if(node_type
== MIB_NODE_LR
)
522 struct mib_list_rootnode
*lrn
;
523 struct mib_list_node
*ln
;
527 /* list root node (internal 'RAM', variable length) */
528 lrn
= (struct mib_list_rootnode
*)node
;
530 /* iterate over list, head to tail */
531 while ((ln
!= NULL
) && (ln
->objid
!= *ident
))
537 /* found it, proceed to child */;
538 LWIP_DEBUGF(SNMP_MIB_DEBUG
,("ln->objid==%"S32_F
" *ident==%"S32_F
"\n",ln
->objid
,*ident
));
539 if (ln
->nptr
== NULL
)
541 np
->ident_len
= ident_len
;
543 return (struct mib_node
*)lrn
;
547 /* follow next child pointer */
556 LWIP_DEBUGF(SNMP_MIB_DEBUG
,("ln search failed *ident==%"S32_F
"\n",*ident
));
562 /* search failed, short object identifier (nosuchname) */
563 LWIP_DEBUGF(SNMP_MIB_DEBUG
,("ln search failed, short object identifier\n"));
567 else if(node_type
== MIB_NODE_EX
)
569 struct mib_external_node
*en
;
574 /* external node (addressing and access via functions) */
575 en
= (struct mib_external_node
*)node
;
578 len
= en
->level_length(en
->addr_inf
,ext_level
);
579 while ((i
< len
) && (en
->ident_cmp(en
->addr_inf
,ext_level
,i
,*ident
) != 0))
587 en
->get_objid(en
->addr_inf
,ext_level
,i
,&debug_id
);
588 LWIP_DEBUGF(SNMP_MIB_DEBUG
,("en->objid==%"S32_F
" *ident==%"S32_F
"\n",debug_id
,*ident
));
589 if ((ext_level
+ 1) == en
->tree_levels
)
591 np
->ident_len
= ident_len
;
593 return (struct mib_node
*)en
;
597 /* found it, proceed to child */
606 LWIP_DEBUGF(SNMP_MIB_DEBUG
,("en search failed *ident==%"S32_F
"\n",*ident
));
612 /* search failed, short object identifier (nosuchname) */
613 LWIP_DEBUGF(SNMP_MIB_DEBUG
,("en search failed, short object identifier\n"));
617 else if (node_type
== MIB_NODE_SC
)
621 sn
= (mib_scalar_node
*)node
;
622 if ((ident_len
== 1) && (*ident
== 0))
624 np
->ident_len
= ident_len
;
626 return (struct mib_node
*)sn
;
630 /* search failed, short object identifier (nosuchname) */
631 LWIP_DEBUGF(SNMP_MIB_DEBUG
,("search failed, invalid object identifier length\n"));
637 /* unknown node_type */
638 LWIP_DEBUGF(SNMP_MIB_DEBUG
,("search failed node_type %"U16_F
" unkown\n",(u16_t
)node_type
));
642 /* done, found nothing */
643 LWIP_DEBUGF(SNMP_MIB_DEBUG
,("search failed node==%p\n",(void*)node
));
648 * Test table for presence of at least one table entry.
651 empty_table(struct mib_node
*node
)
658 node_type
= node
->node_type
;
659 if (node_type
== MIB_NODE_LR
)
661 struct mib_list_rootnode
*lrn
;
662 lrn
= (struct mib_list_rootnode
*)node
;
663 if ((lrn
->count
== 0) || (lrn
->head
== NULL
))
668 else if ((node_type
== MIB_NODE_AR
) || (node_type
== MIB_NODE_RA
))
670 struct mib_array_node
*an
;
671 an
= (struct mib_array_node
*)node
;
672 if ((an
->maxlength
== 0) || (an
->nptr
== NULL
))
677 else if (node_type
== MIB_NODE_EX
)
679 struct mib_external_node
*en
;
680 en
= (struct mib_external_node
*)node
;
681 if (en
->tree_levels
== 0)
694 snmp_expand_tree(struct mib_node
*node
, u8_t ident_len
, s32_t
*ident
, struct snmp_obj_id
*oidret
)
696 u8_t node_type
, ext_level
, climb_tree
;
699 /* reset node stack */
704 node_type
= node
->node_type
;
705 if ((node_type
== MIB_NODE_AR
) || (node_type
== MIB_NODE_RA
))
707 struct mib_array_node
*an
;
710 /* array node (internal ROM or RAM, fixed length) */
711 an
= (struct mib_array_node
*)node
;
715 while ((i
< an
->maxlength
) && (an
->objid
[i
] < *ident
))
719 if (i
< an
->maxlength
)
721 LWIP_DEBUGF(SNMP_MIB_DEBUG
,("an->objid[%"U16_F
"]==%"S32_F
" *ident==%"S32_F
"\n",i
,an
->objid
[i
],*ident
));
722 /* add identifier to oidret */
723 oidret
->id
[oidret
->len
] = an
->objid
[i
];
726 if (an
->nptr
[i
] == NULL
)
728 LWIP_DEBUGF(SNMP_MIB_DEBUG
,("leaf node\n"));
729 /* leaf node (e.g. in a fixed size table) */
730 if (an
->objid
[i
] > *ident
)
732 return (struct mib_node
*)an
;
734 else if ((i
+ 1) < an
->maxlength
)
736 /* an->objid[i] == *ident */
738 oidret
->id
[oidret
->len
] = an
->objid
[i
+ 1];
740 return (struct mib_node
*)an
;
744 /* (i + 1) == an->maxlength */
754 LWIP_DEBUGF(SNMP_MIB_DEBUG
,("non-leaf node\n"));
755 /* non-leaf, store right child ptr and id */
757 while ((j
< an
->maxlength
) && (empty_table(an
->nptr
[j
])))
761 if (j
< an
->maxlength
)
763 cur_node
.r_ptr
= an
->nptr
[j
];
764 cur_node
.r_id
= an
->objid
[j
];
769 cur_node
.r_ptr
= NULL
;
771 push_node(&cur_node
);
772 if (an
->objid
[i
] == *ident
)
779 /* an->objid[i] < *ident */
782 /* follow next child pointer */
788 /* i == an->maxlength */
795 /* ident_len == 0, complete with leftmost '.thing' */
797 while ((j
< an
->maxlength
) && empty_table(an
->nptr
[j
]))
801 if (j
< an
->maxlength
)
803 LWIP_DEBUGF(SNMP_MIB_DEBUG
,("left an->objid[j]==%"S32_F
"\n",an
->objid
[j
]));
804 oidret
->id
[oidret
->len
] = an
->objid
[j
];
806 if (an
->nptr
[j
] == NULL
)
809 return (struct mib_node
*)an
;
813 /* no leaf, continue */
819 /* j == an->maxlength */
824 else if(node_type
== MIB_NODE_LR
)
826 struct mib_list_rootnode
*lrn
;
827 struct mib_list_node
*ln
;
829 /* list root node (internal 'RAM', variable length) */
830 lrn
= (struct mib_list_rootnode
*)node
;
834 /* iterate over list, head to tail */
835 while ((ln
!= NULL
) && (ln
->objid
< *ident
))
841 LWIP_DEBUGF(SNMP_MIB_DEBUG
,("ln->objid==%"S32_F
" *ident==%"S32_F
"\n",ln
->objid
,*ident
));
842 oidret
->id
[oidret
->len
] = ln
->objid
;
844 if (ln
->nptr
== NULL
)
847 if (ln
->objid
> *ident
)
849 return (struct mib_node
*)lrn
;
851 else if (ln
->next
!= NULL
)
853 /* ln->objid == *ident */
855 oidret
->id
[oidret
->len
] = ln
->next
->objid
;
857 return (struct mib_node
*)lrn
;
861 /* ln->next == NULL */
868 struct mib_list_node
*jn
;
871 /* non-leaf, store right child ptr and id */
873 while ((jn
!= NULL
) && empty_table(jn
->nptr
))
879 cur_node
.r_ptr
= jn
->nptr
;
880 cur_node
.r_id
= jn
->objid
;
885 cur_node
.r_ptr
= NULL
;
887 push_node(&cur_node
);
888 if (ln
->objid
== *ident
)
895 /* ln->objid < *ident */
898 /* follow next child pointer */
911 struct mib_list_node
*jn
;
912 /* ident_len == 0, complete with leftmost '.thing' */
914 while ((jn
!= NULL
) && empty_table(jn
->nptr
))
920 LWIP_DEBUGF(SNMP_MIB_DEBUG
,("left jn->objid==%"S32_F
"\n",jn
->objid
));
921 oidret
->id
[oidret
->len
] = jn
->objid
;
923 if (jn
->nptr
== NULL
)
926 LWIP_DEBUGF(SNMP_MIB_DEBUG
,("jn->nptr == NULL\n"));
927 return (struct mib_node
*)lrn
;
931 /* no leaf, continue */
942 else if(node_type
== MIB_NODE_EX
)
944 struct mib_external_node
*en
;
947 /* external node (addressing and access via functions) */
948 en
= (struct mib_external_node
*)node
;
954 len
= en
->level_length(en
->addr_inf
,ext_level
);
955 while ((i
< len
) && (en
->ident_cmp(en
->addr_inf
,ext_level
,i
,*ident
) < 0))
961 /* add identifier to oidret */
962 en
->get_objid(en
->addr_inf
,ext_level
,i
,&ex_id
);
963 LWIP_DEBUGF(SNMP_MIB_DEBUG
,("en->objid[%"U16_F
"]==%"S32_F
" *ident==%"S32_F
"\n",i
,ex_id
,*ident
));
964 oidret
->id
[oidret
->len
] = ex_id
;
967 if ((ext_level
+ 1) == en
->tree_levels
)
969 LWIP_DEBUGF(SNMP_MIB_DEBUG
,("leaf node\n"));
973 return (struct mib_node
*)en
;
975 else if ((i
+ 1) < len
)
977 /* ex_id == *ident */
978 en
->get_objid(en
->addr_inf
,ext_level
,i
+ 1,&ex_id
);
980 oidret
->id
[oidret
->len
] = ex_id
;
982 return (struct mib_node
*)en
;
996 LWIP_DEBUGF(SNMP_MIB_DEBUG
,("non-leaf node\n"));
997 /* non-leaf, store right child ptr and id */
1001 /* right node is the current external node */
1002 cur_node
.r_ptr
= node
;
1003 en
->get_objid(en
->addr_inf
,ext_level
,j
,&cur_node
.r_id
);
1004 cur_node
.r_nl
= ext_level
+ 1;
1008 cur_node
.r_ptr
= NULL
;
1010 push_node(&cur_node
);
1011 if (en
->ident_cmp(en
->addr_inf
,ext_level
,i
,*ident
) == 0)
1018 /* external id < *ident */
1021 /* proceed to child */
1027 /* i == len (en->level_len()) */
1033 /* ident_len == 0, complete with leftmost '.thing' */
1034 en
->get_objid(en
->addr_inf
,ext_level
,0,&ex_id
);
1035 LWIP_DEBUGF(SNMP_MIB_DEBUG
,("left en->objid==%"S32_F
"\n",ex_id
));
1036 oidret
->id
[oidret
->len
] = ex_id
;
1038 if ((ext_level
+ 1) == en
->tree_levels
)
1041 LWIP_DEBUGF(SNMP_MIB_DEBUG
,("(ext_level + 1) == en->tree_levels\n"));
1042 return (struct mib_node
*)en
;
1046 /* no leaf, proceed to child */
1051 else if(node_type
== MIB_NODE_SC
)
1053 mib_scalar_node
*sn
;
1056 sn
= (mib_scalar_node
*)node
;
1064 /* ident_len == 0, complete object identifier */
1065 oidret
->id
[oidret
->len
] = 0;
1068 LWIP_DEBUGF(SNMP_MIB_DEBUG
,("completed scalar leaf\n"));
1069 return (struct mib_node
*)sn
;
1074 /* unknown/unhandled node_type */
1075 LWIP_DEBUGF(SNMP_MIB_DEBUG
,("expand failed node_type %"U16_F
" unkown\n",(u16_t
)node_type
));
1083 /* find right child ptr */
1087 while ((node_stack_cnt
> 0) && (child
.r_ptr
== NULL
))
1090 /* trim returned oid */
1093 if (child
.r_ptr
!= NULL
)
1095 /* incoming ident is useless beyond this point */
1097 oidret
->id
[oidret
->len
] = child
.r_id
;
1100 ext_level
= child
.r_nl
;
1104 /* tree ends here ... */
1105 LWIP_DEBUGF(SNMP_MIB_DEBUG
,("expand failed, tree ends here\n"));
1110 /* done, found nothing */
1111 LWIP_DEBUGF(SNMP_MIB_DEBUG
,("expand failed node==%p\n",(void*)node
));
1116 * Test object identifier for the iso.org.dod.internet prefix.
1118 * @param ident_len the length of the supplied object identifier
1119 * @param ident points to the array of sub identifiers
1120 * @return 1 if it matches, 0 otherwise
1123 snmp_iso_prefix_tst(u8_t ident_len
, s32_t
*ident
)
1125 if ((ident_len
> 3) &&
1126 (ident
[0] == 1) && (ident
[1] == 3) &&
1127 (ident
[2] == 6) && (ident
[3] == 1))
1138 * Expands object identifier to the iso.org.dod.internet
1139 * prefix for use in getnext operation.
1141 * @param ident_len the length of the supplied object identifier
1142 * @param ident points to the array of sub identifiers
1143 * @param oidret points to returned expanded object identifier
1144 * @return 1 if it matches, 0 otherwise
1146 * @note ident_len 0 is allowed, expanding to the first known object id!!
1149 snmp_iso_prefix_expand(u8_t ident_len
, s32_t
*ident
, struct snmp_obj_id
*oidret
)
1151 const s32_t
*prefix_ptr
;
1156 prefix_ptr
= &prefix
[0];
1157 ret_ptr
= &oidret
->id
[0];
1158 ident_len
= ((ident_len
< 4)?ident_len
:4);
1159 while ((i
< ident_len
) && ((*ident
) <= (*prefix_ptr
)))
1161 *ret_ptr
++ = *prefix_ptr
++;
1167 /* match, complete missing bits */
1170 *ret_ptr
++ = *prefix_ptr
++;
1178 /* i != ident_len */
1183 #endif /* LWIP_SNMP */