1 | /***************************************
2 | $Revision: 1.35 $
3 |
4 | Radix tree (rx). rx_search.c - functions to search nodes of the tree
5 |
6 | Status: NOT REVUED, TESTED, COMPLETE
7 |
8 | Design and implementation by: Marek Bukowy
9 |
10 | ******************/ /******************
11 | Copyright (c) 1999 RIPE NCC
12 |
13 | All Rights Reserved
14 |
15 | Permission to use, copy, modify, and distribute this software and its
16 | documentation for any purpose and without fee is hereby granted,
17 | provided that the above copyright notice appear in all copies and that
18 | both that copyright notice and this permission notice appear in
19 | supporting documentation, and that the name of the author not be
20 | used in advertising or publicity pertaining to distribution of the
21 | software without specific, written prior permission.
22 |
23 | THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING
24 | ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS; IN NO EVENT SHALL
25 | AUTHOR BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY
26 | DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
27 | AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
28 | OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
29 | ***************************************/
30 |
31 |
32 | #include <erroutines.h>
33 | #include <rxroutines.h>
34 | #include <stubs.h>
35 |
36 | #include "iproutines.h"
37 |
38 | /***************************************************************************/
39 |
40 | /*++++++++++++++
41 | Descends the given tree following the last prefix bit to get [past]
42 | the node with the given prefix.
43 | It fills up a stack of COPIES of nodes, including glue nodes.
44 |
45 | Then it also sets the number of elements on the stack:
46 | set maxdepth to the position where a next one would be written
47 | ( = last + 1, or number of nodes pushed)
48 |
49 | The dmodes:
50 |
51 | RX_STK_QUERY_NOGLUE = (search exact/less spec) stop when
52 | * the current prefix length >= newprefix length
53 | * the current prefix does not match anymore
54 | * do not add glue nodes
55 |
56 | RX_STK_QUERY_ALLNOD = as above, except that the glue and data nodes are
57 | treated equally (i.e. glue nodes are not skipped)
58 |
59 | RX_STK_CREAT = descend until the next non-glue node past the one found
60 | in exact mode (for creation)
61 |
62 | ++++++++++++++*/
63 |
64 | er_ret_t
65 | rx_build_stack(rx_nodcpy_t stack[],
66 | int *maxdepth,
67 | rx_tree_t *tree,
68 | ip_prefix_t *newpref,
69 | rx_stk_mt dmode
70 | )
71 | {
72 | register rx_node_t *curnode;
73 | register int link, quit_now=0;
74 | register int tracedet = ER_is_traced( FAC_RX, ASP_RX_STKBLD_DET);
75 | char bbf[IP_PREFSTR_MAX];
76 |
77 | if( ER_is_traced( FAC_RX, ASP_RX_STKBLD_GEN)) {
78 | IP_pref_b2a( newpref , bbf, IP_PREFSTR_MAX);
79 | ER_dbg_va(FAC_RX, ASP_RX_STKBLD_GEN,
80 | "rx_build_stack: searching for %s in mode %d", bbf, dmode);
81 | }
82 |
83 | *maxdepth = 0;
84 |
85 | if ( tree -> num_nodes == 0) {
86 | /* The tree was empty. */
87 | return RX_OK;
88 | }
89 |
90 | curnode = tree->top_ptr;
91 | /* this works for RAM, for SQL one would have to call a 'getsqlnode' here*/
92 |
93 | /* OK, there is at least one node. Descend the tree */
94 | /* as long as the correct bit length is not exceeded*/
95 | /* or a glue is being found (take the last non-glue node then) */
96 | /* or you run out of nodes in the direction of descending*/
97 |
98 | do {
99 | /* check at the current node, where the one we look for would fit*/
100 | /* (the second argument of IP_addr_bit_get starts with 0,*/
101 | /* so this effectively looks at the bit next to the last significant bit*/
102 | /* of the current node*/
103 |
104 | link = IP_addr_bit_get( & newpref->ip, curnode->prefix.bits );
105 |
106 | /* check conditions for leaving the loop */
107 | if(curnode->child_ptr[link] == NULL) {
108 | /* end of branch. quit after adding the current node to the stack*/
109 | /* (or before - subject to bit test in QUERY mode)*/
110 | quit_now = 1;
111 | }
112 | else {
113 | /* check the node.
114 | BIG DIFFERENCE between the modes:
115 | in CREAT we don't mind the stack to go too deep,
116 | in QUERY it can lead to false answers
117 | (e.g. a /24 is found for a /23 query).
118 |
119 | So this must be "peeled off the stack" later in the search routine,
120 | if both types of stack are to work properly with query searches.
121 | */
122 |
123 |
124 | if( curnode->prefix.bits > newpref->bits ) {
125 | /* deep enough.*/
126 | quit_now = 2;
127 | }
128 |
129 | if(dmode == RX_STK_CREAT && curnode->glue) {
130 | /* mode: creation. */
131 | /* Cancel quitting if glue -- in CREAT mode the stack building */
132 | /* should stop at the next real (non-glue) node.*/
133 | /* ("next" meaning following link #0)*/
134 | quit_now = 0;
135 | }
136 | }
137 |
138 | /* now that the conditions for leaving the loop after the node is
139 | added on the stack, see if we shouldn't leave the loop BEFOREHAND */
140 |
141 | /* In query mode, we should quit as soon as we see a mismatch */
142 |
143 | if(dmode != RX_STK_CREAT
144 | && 0 != IP_addr_cmp(&curnode->prefix.ip, &newpref->ip,
145 | curnode->prefix.bits) ) {
146 | /*QUIT NOW! (but add this node)*/
147 | quit_now = 4;
148 | }
149 |
150 | /* push the current node on the stack. RAM only.*/
151 | /* */
152 | /* (unless quit_now is 64 which means do NOT copy the current node.*/
153 | /**/
154 | /* In CREAT and QUERY_ALLNOD modes, push everything. */
155 | /* In QUERY_NOGLUE mode, only non-glues.*/
156 |
157 | if( /* quit_now < 64 && disabled as 64 is not in use right now */
158 | (dmode != RX_STK_QUERY_NOGLUE || curnode->glue == 0 )) {
159 | memcpy( & stack[*maxdepth].cpy, curnode, sizeof(rx_node_t));
160 | stack[*maxdepth].srcptr = curnode;
161 | stack[*maxdepth].srckey = SQ_NOKEY;
162 | stack[*maxdepth].tree = tree;
163 | (*maxdepth)++;
164 | }
165 |
166 | /* make debug info.*/
167 |
168 | if( tracedet ) {
169 | IP_pref_b2a( & curnode->prefix , bbf, IP_PREFSTR_MAX );
170 | ER_dbg_va(FAC_RX, ASP_RX_STKBLD_DET,
171 | "rx_build_stack: %s%d at %s%s (stk len: %d)",
172 | quit_now ? "stop/" : "link ",
173 | quit_now ? quit_now : link,
174 | bbf, ( curnode->glue ) ? " ++glue++" : "",
175 | *maxdepth );
176 | }
177 |
178 | curnode = curnode -> child_ptr[link];
179 |
180 | } while( !quit_now );
181 |
182 | return RX_OK;
183 | }
184 |
185 | /***************************************************************************/
186 | /*+++++++++
187 | helper for the nod_search routine:
188 |
189 | allocate a new node copy struct, copy the struct and add to nodlist
190 | ++++++++++*/
191 |
192 | static
193 | er_ret_t
194 | rx_nod_append( GList **nodlist, rx_nodcpy_t *element)
195 | {
196 | rx_nodcpy_t *newcpy;
197 | er_ret_t err;
198 |
199 | if( (err=wr_calloc( (void **) & newcpy, 1, sizeof(rx_nodcpy_t))) != UT_OK) {
200 | return err; /* die;*/
201 | }
202 | memcpy(newcpy, element, sizeof(rx_nodcpy_t));
203 | (*nodlist) = g_list_prepend( *nodlist, newcpy );
204 |
205 | return RX_OK;
206 | }
207 |
208 |
209 |
210 |
211 | /***************************************************************************/
212 |
213 | /*+++++++++++
214 | helper for MORE specific lookup in rx_nod_search
215 |
216 | adds a node to the list of answers.
217 | +++++++++++*/
218 |
219 | static
220 | er_ret_t
221 | rx_walk_hook_addnode(rx_node_t *node, int level, int nodecounter,
222 | void *userptr)
223 | {
224 | rx_nodcpy_t nodcpy;
225 | hook_addnode_userdat_t *userdat = userptr;
226 |
227 |
228 | /* do not append glue nodes*/
229 | if( node->glue == 1 ) return RX_OK;
230 |
231 | /* in RAM mode, do not copy the node.*/
232 | /* memcpy( &nodcpy.cpy, node, sizeof(rx_node_t));*/
233 |
234 | /* XXX reset to 0 to avoid warnings from workshop: but it
235 | slows things down! */
236 | memset( &nodcpy.cpy, 0, sizeof(rx_node_t));
237 |
238 | nodcpy.srcptr = node;
239 | nodcpy.srckey = SQ_NOKEY;
240 | nodcpy.tree = userdat->tree;
241 |
242 | return rx_nod_append( userdat->nodlist, &nodcpy);
243 | }
244 |
245 |
246 | /***************************************************************************/
247 |
248 | /*+++++++++++
249 | helper for DBLS lookup in rx_nod_search
250 |
251 | adds a node to the list of answers.
252 | +++++++++++*/
253 |
254 | static
255 | er_ret_t
256 | rx_walk_hook_adddoubles(rx_node_t *node, int level, int nodecounter,
257 | void *userptr)
258 | {
259 | rx_nodcpy_t nodcpy;
260 | hook_addnode_userdat_t *userdat = userptr;
261 | int leaves = g_list_length(node->leaves_ptr);
262 | char buf[1024];
263 |
264 | /* do not append glue nodes*/
265 | if( node->glue == 1 ) return RX_OK;
266 |
267 |
268 | /* add only nodes with more than 1 dataleaf*/
269 | if( leaves < 2 ) return RX_OK;
270 |
271 | if( ER_is_traced( FAC_RX, ASP_RX_SRCH_DET)) {
272 | rx_nod_print(node, buf, 1024);
273 | ER_dbg_va(FAC_RX, ASP_RX_SRCH_DET,
274 | "rx_walk_hook_adddoubles: %30s, %d leaves", buf, leaves);
275 | }
276 |
277 | /* memcpy( &nodcpy.cpy, node, sizeof(rx_node_t));*/
278 | nodcpy.srcptr = node;
279 | nodcpy.srckey = SQ_NOKEY;
280 | nodcpy.tree = userdat->tree;
281 |
282 | return rx_nod_append( userdat->nodlist, &nodcpy);
283 | }
284 |
285 |
286 | /***************************************************************************/
287 | er_ret_t
288 | rx_nod_search (
289 | rx_srch_mt search_mode,
290 | int par_a,
291 | int par_b,
292 | /* see rx_asc_search() for explanation */
293 | rx_tree_t *tree, /* tree ptr*/
294 | ip_prefix_t *prefix, /* binary prefix*/
295 |
296 | rx_nodcpy_t stack[], /* stack==array of node_copies*/
297 | int stackcount, /* number of element on the stack,*/
298 | /* can come from a creat stack!*/
299 |
300 | GList **nodlist, /* answers go here*/
301 | int max_count /* max # of answers*/
302 | )
303 | /*
304 | searches the stack for a given prefix, finds *nodes* in the stack
305 | and appends *copies of the nodes* to the nodlist;
306 |
307 | finds
308 | 0 or 1 nodes for exact search
309 | 0 or 1 nodes for exless (0 if no less specific node found)
310 | any number (incl. 0) for {more|less}^n-m specific
311 |
312 | returns errcode.
313 |
314 |
315 | */
316 | {
317 | char buf[1024];
318 | int sps = stackcount-1; /* stack position.*/
319 | int depthcounter=0;
320 | er_ret_t err=RX_OK;
321 | int i;
322 | hook_addnode_userdat_t datstr;
323 | er_ret_t (*hook_function)(); /* pointer to the walk_hook function*/
324 | /* (see MORE spec lookup)*/
325 |
326 | /* structure for carrying data to walk_tree hook functions, used only
327 | in MORE, DBLS and RANG search modes
328 | */
329 | datstr.nodlist = nodlist;
330 | datstr.tree = tree;
331 | datstr.prefix = prefix;
332 |
333 |
334 | if( ER_is_traced( FAC_RX, ASP_RX_SRCH_DET)) {
335 | IP_pref_b2a( prefix , buf, IP_PREFSTR_MAX);
336 | ER_dbg_va(FAC_RX, ASP_RX_SRCH_GEN,
337 | "rx_nod_search: searching for %s in mode %d (%s)",
338 | buf, search_mode, RX_text_srch_mode(search_mode) );
339 | }
340 |
341 | /* in non-CREAT modes, glue nodes are skipped anyway.
342 | (they should normally not be there if the stack was created in
343 | the STK_QUERY mode, but it's possible to use a CREAT stack too).
344 |
345 | It's also possible that the stack is too deep.
346 | So, truncate the stack to the last non-glue node
347 | of the length <= search term.
348 | otherwise a /24 would be returned for a /23 query.
349 |
350 | For LESS SPECIFIC searches one has to peel off entries
351 | whose prefixes do not contain the search term,
352 | */
353 |
354 | if( search_mode != RX_SRCH_CREAT ) {
355 |
356 | while( sps >= 0 ) {
357 | char *reason = NULL;
358 |
359 | if( stack[sps].cpy.prefix.bits > prefix->bits ) { /* too deep*/
360 | reason = "2deep";
361 | }
362 | else if( 0 != IP_addr_cmp(& stack[sps].cpy.prefix.ip, &prefix->ip,
363 | stack[sps].cpy.prefix.bits) ) { /* mismatch */
364 | reason = "mismatch";
365 | }
366 | else if ( search_mode != RX_SRCH_MORE && search_mode != RX_SRCH_DBLS
367 | && search_mode != RX_SRCH_RANG && stack[sps].cpy.glue == 1 ) { /* is glue*/
368 | reason = "glue";
369 | }
370 | #if 0
371 | /* mhm. it can't be limited here, must be done in RP */
372 | else if ( search_mode == RX_SRCH_LESS && par_a == 1
373 | && stack[sps].cpy.prefix.bits == prefix->bits ) { /* too deep*/
374 | reason = "2deep4less";
375 | }
376 | #endif
377 |
378 | else {
379 |
380 | break; /* stop peeling off */
381 | }
382 |
383 | if( ER_is_traced( FAC_RX, ASP_RX_SRCH_DET)) {
384 | rx_nod_print( & stack[sps].cpy , buf, IP_PREFSTR_MAX);
385 | ER_dbg_va(FAC_RX, ASP_RX_SRCH_DET,
386 | "rx_nod_search: peeling off %d: %s (%s)", sps, buf, reason);
387 | }
388 | sps--;
389 | }
390 | }
391 |
392 | /* nothing left on the stack. Sorry.*/
393 | /* we allow that for more spec search -- this means*/
394 | /* that the search term is a shorter prefix than the one*/
395 | /* in the top node. Possibly it's 0/0 which is valid for more spec search.*/
396 |
397 | if( search_mode != RX_SRCH_MORE && search_mode != RX_SRCH_DBLS
398 | && sps < 0 ) {
399 | return RX_OK;
400 | }
401 |
402 | switch(search_mode) {
403 | case RX_SRCH_EXACT:
404 | case RX_SRCH_CREAT:
405 | /* go up the tree (stack) and exit when the proper prefix is found.*/
406 | /* For RX_SRCH_EXACT skip glue nodes, for RX_SRCH_CREAT take all.*/
407 | /* They may contain a valid prefix, so watch out.*/
408 |
409 | while(sps >= 0) {
410 |
411 | if( ER_is_traced( FAC_RX, ASP_RX_SRCH_DET)) {
412 | rx_nod_print(& stack[sps].cpy, buf, 1024);
413 | ER_dbg_va(FAC_RX, ASP_RX_SRCH_DET,
414 | "rx_nod_search: position %d: %s", sps, buf);
415 | }
416 |
417 | if ( search_mode == RX_SRCH_EXACT
418 | && stack[sps].cpy.glue ) {
419 | die;
420 | }
421 |
422 | if ( memcmp( & stack[sps].cpy.prefix,
423 | prefix,
424 | sizeof(ip_prefix_t)) == 0 ) {
425 | /* FOUND!!*/
426 | /* add to the nodlist.*/
427 |
428 | if( (err=rx_nod_append( nodlist, & stack[sps])) != RX_OK ) {
429 | return err;
430 | }
431 |
432 | ER_dbg_va(FAC_RX, ASP_RX_SRCH_DET, "rx_nod_search: found!");
433 | break;
434 | }
435 | sps--;
436 | }
437 | break;
438 |
439 | case RX_SRCH_EXLESS:
440 | /* just fetch the last element off the stack (if any). */
441 | /* Must be non-glue for EXLESS.*/
442 |
443 | if( sps >= 0 ) {
444 | rx_nod_append( nodlist, & stack[sps]);
445 | }
446 |
447 | /* else : nothing found.*/
448 | /* For EXLESS: check if the stack contains only non-glue nodes.*/
449 | /* If it contains a glue, it means it was created in the CREAT mode,*/
450 | /* which renders the above algorithm absolutely useless. Then crash,*/
451 | /* this is a programmer's error.*/
452 |
453 | while( sps >= 0 ) {
454 | if( stack[sps].cpy.glue ) {
455 | die;
456 | }
457 | sps--;
458 | }
459 |
460 | break;
461 |
462 | case RX_SRCH_LESS:
463 | while( sps >= 0 && depthcounter < par_a ) {
464 | if( stack[sps].cpy.glue == 0 ) {
465 | rx_nod_append( nodlist, & stack[sps]);
466 | depthcounter++;
467 | }
468 | sps--;
469 | }
470 | break;
471 |
472 | case RX_SRCH_MORE:
473 | case RX_SRCH_DBLS: /* special (debug?) mode : find nodes with multiple*/
474 | /* data leaves. Much like more specific, except that*/
475 | /* most nodes will be skipped.*/
476 | /* The difference is in calling another hook function*/
477 | hook_function = ( search_mode == RX_SRCH_MORE )
478 | ? rx_walk_hook_addnode
479 | : rx_walk_hook_adddoubles;
480 |
481 | /* the result of a more spec search should NOT contain the object exactly*/
482 | /* matching the query, even if it exists in the database. So two walks are */
483 | /* performed, one for each child (if it exists). */
484 | /* MEMORY IMPLEMENTATION ONLY FOR THE MOMENT*/
485 |
486 | /* start from the top node if the searched prefix is between the
487 | top node and the first node on the stack (i.e. the first node is
488 | contained within the search term) */
489 |
490 | /* COVERS THE CASE 0.0.0.0/0 */
491 | /* or any other prefix that the tree might be set to represent,*/
492 | /* but there is no actual object for it (not even glue)*/
493 |
494 | if( sps < 0 ) {
495 | if( tree->num_nodes > 0 /* there is any node in the tree */
496 | && 0 == IP_addr_cmp( & prefix->ip,
497 | & stack[0].cpy.prefix.ip,
498 | prefix->bits) ) { /* addr match */
499 | rx_walk_tree( tree->top_ptr, hook_function,
500 | /* RX_WALK_REVERS | */ RX_WALK_SKPGLU, /* skip glue nodes while counting*/
501 | par_a, /* display this many levels */
502 | 0, 0, &datstr, &err);
503 | if( err != RX_OK ) {
504 | return err;
505 | }
506 | }
507 | } /* if nothing on stack */
508 | else {
509 |
510 | /* walk from this node if it matches the query prefix and is
511 | long enough (if it is shorter, then it will harvest too many
512 | results
513 | */
514 | if( prefix->bits <= stack[sps].srcptr->prefix.bits
515 | && 0 == IP_addr_cmp( & stack[sps].srcptr->prefix.ip,
516 | & prefix->ip,
517 | prefix->bits) ) {
518 | rx_walk_tree( stack[sps].srcptr, hook_function,
519 | /* RX_WALK_REVERS | */ RX_WALK_SKPGLU, /* skip glue nodes while counting*/
520 | par_a, /* display up to this max length*/
521 | 0, 0, &datstr, &err);
522 | if( err != RX_OK ) {
523 | return err;
524 | }
525 | }
526 | else {
527 | /* or walk the child nodes otherwise (still check the address) */
528 |
529 | for( i = 1; i >= 0; i--) {
530 | if( stack[sps].cpy.child_ptr[i] != NULL ) {
531 | if( ER_is_traced( FAC_RX, ASP_RX_SRCH_DET)) {
532 | IP_pref_b2a(& stack[sps].cpy.child_ptr[i]->prefix, buf, 1023);
533 | }
534 |
535 | if( 0 == IP_addr_cmp( & stack[sps].cpy.child_ptr[i]->prefix.ip,
536 | & prefix->ip,
537 | prefix->bits) ) {
538 |
539 | ER_dbg_va(FAC_RX, ASP_RX_SRCH_DET,
540 | "rx_nod_search: digging child %d: %s", i, buf);
541 |
542 | rx_walk_tree( stack[sps].cpy.child_ptr[i], hook_function,
543 | /* RX_WALK_REVERS | */ RX_WALK_SKPGLU, /* skip glue nodes while counting*/
544 | par_a, /* display this many levels */
545 | 0, 0, &datstr, &err);
546 | if( err != RX_OK ) {
547 | return err;
548 | }
549 | }
550 | else {
551 | ER_dbg_va(FAC_RX, ASP_RX_SRCH_DET,
552 | "rx_nod_search: prefix mismatch with child %d: %s",
553 | i, buf);
554 | }
555 | }
556 | }
557 | } /* if node does not match, dig child nodes */
558 |
559 | }
560 | break;
561 |
562 | case RX_SRCH_RANG:
563 | /* OK, start from the node at the end of the stack (exless match including
564 | glue nodes) then
565 |
566 |
567 | if its prefix length is
568 | OK -> found! descend from here as long as the prefixes are in range
569 | shorter -> apparently there is even no such glue node. come back down
570 | one step
571 |
572 | */
573 |
574 | i = sps; /* go up the tree (down the stack) */
575 | /* until too far (one node too much, after >= )*/
576 | while( i >= 0 && stack[i].cpy.prefix.bits >= prefix->bits ) {
577 | i--;
578 | }
579 |
580 | /* look where you are:*/
581 |
582 | if( i < 0 ) /* it was the top object, but its prefix was too long*/
583 | i=0; /* take the top object as the base*/
584 | else
585 | i++; /* went one too much, now come back one step*/
586 |
587 |
588 | rx_walk_tree( stack[i].srcptr, rx_walk_hook_addnode,
589 | RX_WALK_PRFLEN, /* skip glue nodes while counting*/
590 | par_a, /* display up to this max length*/
591 | 0, 0, &datstr, &err);
592 | if( err != RX_OK ) {
593 | return err;
594 | }
595 |
596 | break;
597 |
598 | /* return RX_NOYETI;*/
599 | /*not implemented*/
600 | /* die; */
601 | default:
602 | die; /* are you nuts??*/
603 | }
604 |
605 | return err;
606 |
607 | }
608 |
609 |
610 |
611 | /*****************************************************************************/
612 |
613 | /*+++++++++++++
614 | builds a stack for this prefix, finds *nodes* in the stack
615 | and appends *copies of the data leaves* to the LL of answers;
616 |
617 | sorts by SQL object keys and uniq's the data
618 |
619 | finds:
620 | 0 or 1 nodes for exact search
621 | 0 or 1 nodes for exless (0 if no less specific node found)
622 | any number (incl. 0) for {more|less}-n specific
623 |
624 | then copies the nodes/dataleaves to the answer structs and appends them
625 | to the given LL. So, effectively, the number of answers can be
626 | anything from 0 to infinity, because objects may be duplicate
627 | even at the same node.
628 |
629 | returns errcode.
630 |
631 | algorithm:
632 |
633 | builds stack[MAXBIT (==128)];
634 |
635 | if( more/less-depth && par_a == 0)
636 |
637 | run rx_nod_search, then
638 |
639 | if(more spec) rx_nod_walk(maxdepth=n, append_to_LL() );
640 | if(less spec) do { append(LL, stack[i]) } while(i-- && n--);
641 | otherwise just set LL
642 |
643 |
644 | The routine provides _at_least_ max_count answers.
645 | It will *try* to stop after max_count as soon as possible
646 | - but it's the higher level routine that should do the final cut.
647 | +++++++++++++++*/
648 |
649 | er_ret_t
650 | RX_bin_search (
651 | rx_srch_mt search_mode,
652 | int par_a,
653 | int par_b,
654 | rx_tree_t *tree, /* tree ptr*/
655 | ip_prefix_t *prefix, /* binary prefix*/
656 | GList **datleaves, /* data leaves go here*/
657 | int max_count
658 | )
659 |
660 | {
661 | rx_nodcpy_t stack[128];
662 | unsigned k;
663 | int stkcnt, resnum = 0, maxleaves;
664 | GList *nodlist = NULL, *nitem;
665 | rx_node_t *curnode;
666 | rx_nodcpy_t *curcpy;
667 | rx_datref_t *datref;
668 | rx_stk_mt dmode;
669 |
670 | /* more specific node search may start from a glue node, */
671 | /* for all others the stack should not contain glues.*/
672 |
673 | dmode = ( search_mode == RX_SRCH_MORE
674 | || search_mode == RX_SRCH_DBLS
675 | || search_mode == RX_SRCH_RANG )
676 | ? RX_STK_QUERY_ALLNOD
677 | : RX_STK_QUERY_NOGLUE;
678 |
679 | rx_build_stack(stack, &stkcnt, tree, prefix, dmode);
680 |
681 | rx_nod_search( search_mode, par_a, par_b, tree, prefix,
682 | stack, stkcnt, &nodlist, 1000);
683 |
684 | ER_dbg_va(FAC_RX, ASP_RX_SRCH_DET, "RX_bin_search: processing nodes");
685 |
686 | for( nitem = g_list_first(nodlist);
687 | nitem != NULL;
688 | nitem = g_list_next(nitem)) {
689 |
690 | resnum++;
691 | curcpy = nitem->data;
692 |
693 | /*
694 | if memory mode includes RAM:
695 | * do not expect copies of nodes in the list received from bin_search.
696 | * iterate through data leaves with g_list_nth_data.
697 | */
698 |
699 | curnode = curcpy->srcptr;
700 |
701 | /* rx_nod_print( curnode, buf, 1024 );*/
702 |
703 | maxleaves = g_list_length(curnode->leaves_ptr);
704 | /* fprintf(stderr,"###node %d, %d dataleaves attached:", i, maxleaves);*/
705 |
706 | /* iterate through dataleafs attached to this node*/
707 | for(k=0; k<maxleaves; k++) {
708 | rx_dataleaf_t *leafptr = g_list_nth_data(curnode->leaves_ptr, k);
709 |
710 | /*
711 | check the conditions to add the leaf:
712 |
713 | XXX never add composed inetnum for exact prefix search
714 | (but do for exact range search...) - must be solved in upper layer.
715 |
716 | */
717 |
718 |
719 | /* add*/
720 |
721 | dieif( wr_calloc( (void **) &datref,
722 | sizeof(rx_datref_t), 1) != UT_OK);
723 | datref->leafptr = leafptr;
724 | /* srckey and excluded fields are initialised to 0 by calloc */
725 |
726 | *datleaves = g_list_prepend(*datleaves, datref);
727 | }
728 | }
729 |
730 | wr_clear_list( &nodlist );
731 |
732 | ER_dbg_va(FAC_RX, ASP_RX_SRCH_GEN,
733 | "RX_bin_search: found %d nodes", resnum);
734 |
735 |
736 | /* the LL of answers (*datleaves) contains pointers to answer structs,
737 | that SHOULD BE NORMALIZED HERE (==with no redundant entries)
738 | */
739 |
740 | return RX_OK;
741 | }
742 |