4 // functions to convert tag positions to the corresponding tree node and viceversa.
\r
5 // These are implemented in order to be able to change the tree and Tags representations,
\r
6 // without affecting the code so much.
\r
7 // Current implementation corresponds to balanced-parentheses representation for
\r
8 // the tree, and storing 2 tags per tree node (opening and closing tags).
\r
10 // tag position -> tree node
\r
11 inline treeNode tagpos2node(int t) {
\r
15 // tree node -> tag position
\r
16 inline int node2tagpos(treeNode x) {
\r
20 // Save: saves XML tree data structure to file.
\r
21 void XMLTree::Save(unsigned char *filename)
\r
25 char filenameaux[1024];
\r
28 sprintf(filenameaux, "%s.srx", filename);
\r
29 fp = fopen(filenameaux, "w");
\r
31 printf("Error: cannot create file %s to store the tree structure of XML collection\n", filenameaux);
\r
35 // first stores the tree topology
\r
38 // stores the table with tag names
\r
39 fwrite(&ntagnames, sizeof(int), 1, fp);
\r
40 for (i=0; i<ntagnames;i++)
\r
41 fprintf(fp, "%s\n",TagName[i]);
\r
44 fwrite(&indexing_empty_texts, sizeof(bool), 1, fp);
\r
45 fwrite(&initialized, sizeof(bool), 1, fp);
\r
46 fwrite(&finished, sizeof(bool), 1, fp);
\r
48 if (!indexing_empty_texts) EBVector->save(fp);
\r
53 // stores the texts
\r
61 // Load: loads XML tree data structure from file. Returns
\r
62 // a pointer to the loaded data structure
\r
63 XMLTree *XMLTree::Load(unsigned char *filename, int sample_rate_text)
\r
67 char filenameaux[1024];
\r
71 // first load the tree topology
\r
72 sprintf(filenameaux, "%s.srx", filename);
\r
73 fp = fopen(filenameaux, "r");
\r
75 printf("Error: cannot open file %s to load the tree structure of XML collection\n", filenameaux);
\r
79 XML_Tree = new XMLTree();
\r
81 XML_Tree->Par = (bp *)malloc(sizeof(bp));
\r
83 loadTree(XML_Tree->Par, fp);
\r
85 // stores the table with tag names
\r
86 fread(&XML_Tree->ntagnames, sizeof(int), 1, fp);
\r
88 XML_Tree->TagName = (unsigned char **)malloc(XML_Tree->ntagnames*sizeof(unsigned char *));
\r
90 for (i=0; i<XML_Tree->ntagnames;i++) {
\r
92 fscanf(fp, "%s\n",filenameaux);
\r
93 XML_Tree->TagName[i] = (unsigned char *)malloc(sizeof(unsigned char)*(strlen((const char *)filenameaux)+1));
\r
94 strcpy((char *)XML_Tree->TagName[i], (const char *)filenameaux);
\r
98 fread(&(XML_Tree->indexing_empty_texts), sizeof(bool), 1, fp);
\r
99 fread(&(XML_Tree->initialized), sizeof(bool), 1, fp);
\r
100 fread(&(XML_Tree->finished), sizeof(bool), 1, fp);
\r
102 if (!(XML_Tree->indexing_empty_texts)) XML_Tree->EBVector = static_bitsequence_rrr02::load(fp);
\r
105 XML_Tree->Tags = static_sequence_wvtree::load(fp);
\r
107 // loads the texts
\r
108 //XML_Tree->Text->Load(fp,sample_rate_text);
\r
116 // ~XMLTree: frees memory of XML tree.
\r
117 XMLTree::~XMLTree()
\r
122 free(Par); // frees the memory of struct Par
\r
124 for (i=0; i<ntagnames;i++)
\r
129 if (!indexing_empty_texts) {
\r
130 EBVector->~static_bitsequence_rrr02();
\r
135 Tags->~static_sequence_wvtree();
\r
139 //Text->~TextCollection();
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143 initialized = false;
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147 // root(): returns the tree root.
\r
148 treeNode XMLTree::Root()
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150 return root_node(Par);
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153 // SubtreeSize(x): the number of nodes (and attributes) in the subtree of node x.
\r
154 int XMLTree::SubtreeSize(treeNode x)
\r
156 return subtree_size(Par, x);
\r
159 // SubtreeTags(x,tag): the number of occurrences of tag within the subtree of node x.
\r
160 int XMLTree::SubtreeTags(treeNode x, TagType tag)
\r
162 int s = x + 2*subtree_size(Par, x) - 1;
\r
164 return Tags->rank(tag, s) - Tags->rank(tag, node2tagpos(x)-1);
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167 // IsLeaf(x): returns whether node x is leaf or not. In the succinct representation
\r
168 // this is just a bit inspection.
\r
169 bool XMLTree::IsLeaf(treeNode x)
\r
171 return isleaf(Par, x);
\r
174 // IsAncestor(x,y): returns whether node x is ancestor of node y.
\r
175 bool XMLTree::IsAncestor(treeNode x, treeNode y)
\r
177 return is_ancestor(Par, x, y);
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180 // IsChild(x,y): returns whether node x is parent of node y.
\r
181 bool XMLTree::IsChild(treeNode x, treeNode y)
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183 if (!is_ancestor(Par, x, y)) return false;
\r
184 return depth(Par, x) == (depth(Par, y) + 1);
\r
187 // NumChildren(x): number of children of node x. Constant time with the data structure
\r
189 int XMLTree::NumChildren(treeNode x)
\r
191 return degree(Par, x);
\r
194 // ChildNumber(x): returns i if node x is the i-th children of its parent.
\r
195 int XMLTree::ChildNumber(treeNode x)
\r
197 return child_rank(Par, x);
\r
200 // Depth(x): depth of node x, a simple binary rank on the parentheses sequence.
\r
201 int XMLTree::Depth(treeNode x)
\r
203 return depth(Par, x);
\r
206 // Preorder(x): returns the preorder number of node x, just counting the tree
\r
207 // nodes (i.e., tags, it disregards the texts in the tree).
\r
208 int XMLTree::Preorder(treeNode x)
\r
210 return preorder_rank(Par, x);
\r
213 // Postorder(x): returns the postorder number of node x, just counting the tree
\r
214 // nodes (i.e., tags, it disregards the texts in the tree).
\r
215 int XMLTree::Postorder(treeNode x)
\r
217 return postorder_rank(Par, x);
\r
220 // Tag(x): returns the tag identifier of node x.
\r
221 TagType XMLTree::Tag(treeNode x)
\r
223 return Tags->access(node2tagpos(x));
\r
226 // DocIds(x): returns the range of text identifiers that descend from node x.
\r
227 // returns {NULLT, NULLT} when there are no texts descending from x.
\r
228 range XMLTree::DocIds(treeNode x)
\r
231 if (indexing_empty_texts) { // faster, no rank needed
\r
233 r.max = x+2*subtree_size(Par, x)-2;
\r
235 else { // we are not indexing empty texts, we need rank
\r
236 int min = EBVector->rank1(x-1);
\r
237 int max = EBVector->rank1(x+2*subtree_size(Par, x)-2);
\r
238 if (min==max) { // range is empty, no texts within the subtree of x
\r
242 else { // the range is non-empty, there are texts within the subtree of x
\r
250 // Parent(x): returns the parent node of node x.
\r
251 treeNode XMLTree::Parent(treeNode x)
\r
253 return parent(Par, x);
\r
256 // Child(x,i): returns the i-th child of node x, assuming it exists.
\r
257 treeNode XMLTree::Child(treeNode x, int i)
\r
259 if (i <= OPTD) return naive_child(Par, x, i);
\r
260 else return child(Par, x, i);
\r
263 // FirstChild(x): returns the first child of node x, assuming it exists. Very fast in BP.
\r
264 treeNode XMLTree::FirstChild(treeNode x)
\r
266 return first_child(Par, x);
\r
269 // NextSibling(x): returns the next sibling of node x, assuming it exists.
\r
270 treeNode XMLTree::NextSibling(treeNode x)
\r
272 return next_sibling(Par, x);
\r
275 // PrevSibling(x): returns the previous sibling of node x, assuming it exists.
\r
276 treeNode XMLTree::PrevSibling(treeNode x)
\r
278 return prev_sibling(Par, x);
\r
281 // TaggedChild(x,i,tag): returns the i-th child of node x tagged tag, or NULLT if there is none.
\r
282 // Because of the balanced-parentheses representation of the tree, this operation is not supported
\r
283 // efficiently, just iterating among the children of node x until finding the desired child.
\r
284 treeNode XMLTree::TaggedChild(treeNode x, int i, TagType tag)
\r
288 child = first_child(Par, x); // starts at first child of node x
\r
289 if (child==(treeNode)-1) return NULLT; // node x is a leaf, there is no such child
\r
290 while (child!=(treeNode)-1) {
\r
291 if (Tags->access(node2tagpos(child)) == tag) { // current child is labeled with tag of interest
\r
293 if (i==0) return child; // we have seen i children of x tagged tag, this is the one we are looking for
\r
295 child = next_sibling(Par, x); // OK, let's try with the next child
\r
297 return NULLT; // no such child was found
\r
300 // TaggedDesc(x,tag): returns the first node tagged tag with larger preorder than x and within
\r
301 // the subtree of x. Returns NULLT if there is none.
\r
302 treeNode XMLTree::TaggedDesc(treeNode x, TagType tag)
\r
306 r = (int) Tags->rank(tag, node2tagpos(x));
\r
307 s = (int) Tags->select(tag, r+1);
\r
308 if (s == -1) return NULLT; // there is no such node
\r
309 y = tagpos2node(s); // transforms the tag position into a node position
\r
310 if (!is_ancestor(Par, x, y)) return NULLT; // the next node tagged tag (in preorder) is not within the subtree of x.
\r
314 // TaggedPrec(x,tag): returns the first node tagged tag with smaller preorder than x and not an
\r
315 // ancestor of x. Returns NULLT if there is none.
\r
316 treeNode XMLTree::TaggedPrec(treeNode x, TagType tag)
\r
319 treeNode node_s, root;
\r
320 r = (int)Tags->rank(tag, node2tagpos(x)-1);
\r
321 if (r==0) return NULLT; // there is no such node.
\r
322 s = (int)Tags->select(tag, r);
\r
323 root = root_node(Par);
\r
324 node_s = tagpos2node(s);
\r
325 while (is_ancestor(Par, node_s, x) && (node_s!=root)) { // the one that we found is an ancestor of x
\r
327 if (r==0) return NULLT; // there is no such node
\r
328 s = (int)Tags->select(tag, r); // we should use select_prev instead when provided
\r
329 node_s = tagpos2node(s);
\r
331 return NULLT; // there is no such node
\r
334 // TaggedFoll(x,tag): returns the first node tagged tag with larger preorder than x and not in
\r
335 // the subtree of x. Returns NULLT if there is none.
\r
336 treeNode XMLTree::TaggedFoll(treeNode x, TagType tag)
\r
339 r = (int) Tags->rank(tag, node2tagpos(next_sibling(Par, x))-1);
\r
340 s = (int) Tags->select(tag, r+1); // select returns -1 in case that there is no r+1-th tag.
\r
341 if (s==-1) return NULLT;
\r
342 else return tagpos2node(s);
\r
345 // PrevText(x): returns the document identifier of the text to the left
\r
346 // of node x, or NULLT if x is the root node or the text is empty.
\r
347 // Assumes Doc ids start from 0.
\r
348 DocID XMLTree::PrevText(treeNode x)
\r
350 if (x == Root()) return NULLT;
\r
351 if (indexing_empty_texts) // faster, no rank needed
\r
353 else { // we are not indexing empty texts, rank is needed
\r
354 if (EBVector->access(x-1) == 0)
\r
355 return (DocID)NULLT; // there is no text to the left of node (text is empty)
\r
357 return (DocID)EBVector->rank1(x-1)-1; //-1 because document ids start from 0
\r
361 // NextText(x): returns the document identifier of the text to the right
\r
362 // of node x, or NULLT if x is the root node. Assumes Doc ids start from 0.
\r
363 DocID XMLTree::NextText(treeNode x)
\r
365 if (x == Root()) return NULLT;
\r
366 if (indexing_empty_texts) // faster, no rank needed
\r
367 return (DocID)x+2*subtree_size(Par, x)-1;
\r
368 else { // we are not indexing empty texts, rank is needed
\r
369 int p = x+2*subtree_size(Par, x)-1;
\r
370 if (EBVector->access(p) == 0) // there is no text to the right of node
\r
371 return (DocID)NULLT;
\r
373 return (DocID)EBVector->rank1(p)-1; //-1 because document ids start from 0
\r
377 // MyText(x): returns the document identifier of the text below node x,
\r
378 // or NULLT if x is not a leaf node or the text is empty. Assumes Doc
\r
379 // ids start from 0.
\r
380 DocID XMLTree::MyText(treeNode x)
\r
382 if (!IsLeaf(x)) return NULLT;
\r
383 if (indexing_empty_texts) // faster, no rank needed
\r
385 else { // we are not indexing empty texts, rank is needed
\r
386 if (EBVector->access(x) == 0) // there is no text below node x
\r
387 return (DocID)NULLT;
\r
389 return (DocID)EBVector->rank1(x)-1; //-1 because document ids start from 0
\r
393 // TextXMLId(d): returns the preorder of document with identifier d in the tree consisting of
\r
394 // all tree nodes and all text nodes. Assumes that the tree root has preorder 1.
\r
395 int XMLTree::TextXMLId(DocID d)
\r
397 if (indexing_empty_texts)
\r
398 return d + rank_open(Par, d)+1; // +1 because root has preorder 1
\r
399 else { // slower, needs rank and select
\r
400 int s = EBVector->select1(d+1);
\r
401 return rank_open(Par, s) + d + 1; // +1 because root has preorder 1
\r
405 // NodeXMLId(x): returns the preorder of node x in the tree consisting
\r
406 // of all tree nodes and all text nodes. Assumes that the tree root has
\r
408 int XMLTree::NodeXMLId(treeNode x)
\r
410 if (indexing_empty_texts)
\r
411 return x - 1 + rank_open(Par, x);
\r
413 if (x == Root()) return 1; // root node has preorder 1
\r
415 return rank_open(Par, x) + EBVector->rank1(x-1);
\r
419 // ParentNode(d): returns the parent node of document identifier d.
\r
420 treeNode XMLTree::ParentNode(DocID d)
\r
423 if (indexing_empty_texts) s = d;
\r
424 else s = EBVector->select1(d);
\r
426 if (inspect(Par,s) == CP) // is a closing parenthesis
\r
427 return parent(Par, find_open(Par, s));
\r
428 else // is an opening parenthesis
\r
429 return (treeNode)s;
\r
434 // OpenDocument(empty_texts): it starts the construction of the data structure for
\r
435 // the XML document. Parameter empty_texts indicates whether we index empty texts
\r
436 // in document or not. Returns a non-zero value upon success, NULLT in case of error.
\r
437 int XMLTree::OpenDocument(bool empty_texts, int sample_rate_text)
\r
439 initialized = true;
\r
444 indexing_empty_texts = empty_texts;
\r
446 par_aux = (pb *)malloc(sizeof(pb));
\r
448 fprintf(stderr, "Error: not enough memory\n");
\r
451 setbit(par_aux,npar,OP); // marks a new opening parenthesis for the tree root
\r
454 tags_aux = (TagType *)malloc(sizeof(TagType));
\r
456 fprintf(stderr, "Error: not enough memory\n");
\r
460 if (!indexing_empty_texts) {
\r
461 empty_texts_aux = (unsigned int *)malloc(sizeof(unsigned int));
\r
462 if (!empty_texts_aux) {
\r
463 fprintf(stderr, "Error: not enough memory\n");
\r
468 //Text = TextCollection::InitTextCollection(sample_rate_text);
\r
470 return 1; // indicates success in the initialization of the data structure
\r
473 // CloseDocument(): it finishes the construction of the data structure for the XML
\r
474 // document. Tree and tags are represented in the final form, dynamic data
\r
475 // structures are made static, and the flag "finished" is set to true. After that,
\r
476 // the data structure can be queried.
\r
477 int XMLTree::CloseDocument()
\r
479 if (!initialized) { // data structure has not been initialized properly
\r
480 fprintf(stderr, "Error: data structure has not been initialized properly (by calling method OpenDocument)\n");
\r
484 // closing parenthesis for the tree root
\r
485 par_aux = (pb *)realloc(par_aux, sizeof(pb)*(1+npar/(8*sizeof(pb))));
\r
487 fprintf(stderr, "Error: not enough memory\n");
\r
490 setbit(par_aux,npar,CP);
\r
493 // creates the data structure for the tree topology
\r
494 Par = (bp *)malloc(sizeof(bp));
\r
495 bp_construct(Par, npar, par_aux, OPT_DEGREE|0);
\r
496 // creates structure for tags
\r
497 alphabet_mapper * am = new alphabet_mapper_none();
\r
498 static_bitsequence_builder * bmb = new static_bitsequence_builder_rrr02(32);
\r
499 wt_coder * wtc = new wt_coder_huff((uint *)tags_aux,npar-1,am);
\r
500 Tags = new static_sequence_wvtree((uint *) tags_aux, (uint) npar-1, wtc, bmb, am);
\r
502 // makes the text collection static
\r
503 //Text->MakeStatic();
\r
505 // creates the data structure marking the non-empty texts (just in the case it is necessary)
\r
506 if (!indexing_empty_texts)
\r
507 EBVector = new static_bitsequence_rrr02((uint *)empty_texts_aux,(ulong)npar,(uint)32);
\r
511 return 1; // indicates success in the inicialization
\r
515 // NewOpenTag(tagname): indicates the event of finding a new opening tag in the document.
\r
516 // Tag name is given. Returns a non-zero value upon success, and returns NULLT
\r
517 // in case of failing when trying to insert the new tag.
\r
518 int XMLTree::NewOpenTag(unsigned char *tagname)
\r
522 if (!initialized) { // data structure has not been initialized properly
\r
523 fprintf(stderr, "Error: you cannot insert a new opening tag without first calling method OpenDocument first\n");
\r
527 // inserts a new opening parentheses in the bit sequence
\r
528 par_aux = (pb *)realloc(par_aux, sizeof(pb)*(1+npar/(8*sizeof(pb))));
\r
530 fprintf(stderr, "Error: not enough memory\n");
\r
533 setbit(par_aux,npar,OP); // marks a new opening parenthesis
\r
535 // transforms the tagname into a tag identifier. If the tag is new, we insert
\r
536 // it in the table.
\r
537 for (i=0; i<ntagnames; i++)
\r
538 if (strcmp((const char *)tagname,(const char *)TagName[i])==0) break;
\r
540 if (i==ntagnames) { // the tag is a new one, then we insert it
\r
541 TagName = (unsigned char **)realloc(TagName, sizeof(char *)*(ntagnames+1));
\r
544 fprintf(stderr, "Error: not enough memory\n");
\r
549 TagName[i] = (unsigned char *)malloc(sizeof(unsigned char)*(strlen((const char *)tagname)+1));
\r
550 strcpy((char *)TagName[i], (const char *)tagname);
\r
553 tags_aux = (TagType *)realloc(tags_aux, sizeof(TagType)*(npar + 1));
\r
556 fprintf(stderr, "Error: not enough memory\n");
\r
560 tags_aux[npar] = i; // inserts the new tag id within the preorder sequence of tags
\r
569 // NewClosingTag(tagname): indicates the event of finding a new closing tag in the document.
\r
570 // Tag name is given. Returns a non-zero value upon success, and returns NULLT
\r
571 // in case of failing when trying to insert the new tag.
\r
572 int XMLTree::NewClosingTag(unsigned char *tagname)
\r
576 if (!initialized) { // data structure has not been initialized properly
\r
577 fprintf(stderr, "Error: you cannot insert a new closing tag without first calling method OpenDocument first\n");
\r
581 // inserts a new closing parentheses in the bit sequence
\r
582 par_aux = (pb *)realloc(par_aux, sizeof(pb)*(1+npar/(8*sizeof(pb))));
\r
584 fprintf(stderr, "Error: not enough memory\n");
\r
587 setbit(par_aux,npar,CP); // marks a new closing opening parenthesis
\r
589 // transforms the tagname into a tag identifier. If the tag is new, we insert
\r
590 // it in the table.
\r
591 for (i=0; i<ntagnames; i++)
\r
592 if (strcmp((const char *)tagname,(const char *)TagName[i])==0) break;
\r
594 if (i==ntagnames) { // the tag is a new one, then we insert it
\r
595 TagName = (unsigned char **)realloc(TagName, sizeof(char *)*(ntagnames+1));
\r
598 fprintf(stderr, "Error: not enough memory\n");
\r
603 TagName[i] = (unsigned char *)malloc(sizeof(char)*(strlen((const char *)tagname)+1));
\r
604 strcpy((char *)TagName[i], (const char *)tagname);
\r
607 tags_aux = (TagType *)realloc(tags_aux, sizeof(TagType)*(npar + 1));
\r
610 fprintf(stderr, "Error: not enough memory\n");
\r
614 tags_aux[npar] = i; // inserts the new tag id within the preorder sequence of tags
\r
618 return 1; // success
\r
623 // NewText(s): indicates the event of finding a new (non-empty) text s in the document.
\r
624 // The new text is inserted within the text collection. Returns a non-zero value upon
\r
625 // success, NULLT in case of error.
\r
626 int XMLTree::NewText(unsigned char *s)
\r
628 if (!initialized) { // data structure has not been initialized properly
\r
629 fprintf(stderr, "Error: you cannot insert a new text without first calling method OpenDocument first\n");
\r
633 if (!indexing_empty_texts) {
\r
634 empty_texts_aux = (unsigned int *)realloc(empty_texts_aux, sizeof(pb)*(1+(npar-1)/(8*sizeof(pb))));
\r
635 if (!empty_texts_aux) {
\r
636 fprintf(stderr, "Error: not enough memory\n");
\r
640 bitset(empty_texts_aux, npar-1); // marks the non-empty text with a 1 in the bit vector
\r
643 //Text->InsertText(s);
\r
645 return 1; // success
\r
648 // NewEmptyText(): indicates the event of finding a new empty text in the document.
\r
649 // In case of indexing empty and non-empty texts, we insert the empty texts into the
\r
650 // text collection. In case of indexing only non-empty texts, it just indicates an
\r
651 // empty text in the bit vector of empty texts. Returns a non-zero value upon
\r
652 // success, NULLT in case of error.
\r
653 int XMLTree::NewEmptyText()
\r
655 unsigned char c = 0;
\r
656 if (!initialized) { // data structure has not been initialized properly
\r
657 fprintf(stderr, "Error: you cannot insert a new empty text without first calling method OpenDocument first\n");
\r
661 if (!indexing_empty_texts) {
\r
662 empty_texts_aux = (unsigned int *)realloc(empty_texts_aux, sizeof(pb)*(1+(npar-1)/(8*sizeof(pb))));
\r
663 if (!empty_texts_aux) {
\r
664 fprintf(stderr, "Error: not enough memory\n");
\r
668 bitclean(empty_texts_aux, npar-1); // marks the empty text with a 0 in the bit vector
\r
670 // else Text->InsertText(&c); // we insert the empty text just in case we index all the texts
\r
672 return 1; // success
\r
676 // GetTagId: returns the tag identifier corresponding to a given tag name.
\r
677 // Returns NULLT in case that the tag name does not exists.
\r
678 TagType XMLTree::GetTagId(unsigned char *tagname)
\r
681 // this should be changed for more efficient processing
\r
682 for (i=0; i<ntagnames; i++)
\r
683 if (strcmp((const char *)tagname,(const char *)TagName[i])==0) break;
\r
684 if (i==ntagnames) return (TagType)NULLT; // tagname does not exists in the table
\r
689 // GetTagName(tagid): returns the tag name of a given tag identifier.
\r
690 // Returns NULL in case that the tag identifier is not valid.
\r
691 unsigned char *XMLTree::GetTagName(TagType tagid)
\r
695 if (tagid >= ntagnames) return NULL; // invalid tag identifier
\r
696 s = (unsigned char *)malloc((strlen((const char *)TagName[tagid])+1)*sizeof(unsigned char));
\r
697 strcpy((char *)s, (const char *)TagName[tagid]);
\r