From de7387604bb695ab9f688f6cdaeb3efd3a221006 Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Sun, 30 Oct 2016 15:24:40 -0400 Subject: [PATCH] Fix bogus tree-flattening logic in QTNTernary(). QTNTernary() contains logic to flatten, eg, '(a & b) & c' into 'a & b & c', which is all well and good, but it tries to do that to NOT nodes as well, so that '!!a' gets changed to '!a'. Explicitly restrict the conversion to be done only on AND and OR nodes, and add a test case illustrating the bug. In passing, provide some comments for the sadly naked functions in tsquery_util.c, and simplify some baroque logic in QTNFree(), which I think may have been leaking some items it intended to free. Noted while investigating a complaint from Andreas Seltenreich. Back-patch to all supported versions. --- src/backend/utils/adt/tsquery_util.c | 79 ++++++++++++++++++++------- src/test/regress/expected/tsearch.out | 7 +++ src/test/regress/sql/tsearch.sql | 2 + 3 files changed, 68 insertions(+), 20 deletions(-) diff --git a/src/backend/utils/adt/tsquery_util.c b/src/backend/utils/adt/tsquery_util.c index b83a755153..b0033184e7 100644 --- a/src/backend/utils/adt/tsquery_util.c +++ b/src/backend/utils/adt/tsquery_util.c @@ -17,6 +17,9 @@ #include "tsearch/ts_utils.h" #include "miscadmin.h" +/* + * Build QTNode tree for a tsquery given in QueryItem array format. + */ QTNode * QT2QTN(QueryItem *in, char *operand) { @@ -50,6 +53,12 @@ QT2QTN(QueryItem *in, char *operand) return node; } +/* + * Free a QTNode tree. + * + * Referenced "word" and "valnode" items are freed if marked as transient + * by flags. + */ void QTNFree(QTNode *in) { @@ -62,26 +71,27 @@ QTNFree(QTNode *in) if (in->valnode->type == QI_VAL && in->word && (in->flags & QTN_WORDFREE) != 0) pfree(in->word); - if (in->child) + if (in->valnode->type == QI_OPR) { - if (in->valnode) - { - if (in->valnode->type == QI_OPR && in->nchild > 0) - { - int i; + int i; - for (i = 0; i < in->nchild; i++) - QTNFree(in->child[i]); - } - if (in->flags & QTN_NEEDFREE) - pfree(in->valnode); - } - pfree(in->child); + for (i = 0; i < in->nchild; i++) + QTNFree(in->child[i]); } + if (in->child) + pfree(in->child); + + if (in->flags & QTN_NEEDFREE) + pfree(in->valnode); pfree(in); } +/* + * Sort comparator for QTNodes. + * + * The sort order is somewhat arbitrary. + */ int QTNodeCompare(QTNode *an, QTNode *bn) { @@ -131,12 +141,19 @@ QTNodeCompare(QTNode *an, QTNode *bn) } } +/* + * qsort comparator for QTNode pointers. + */ static int cmpQTN(const void *a, const void *b) { return QTNodeCompare(*(QTNode *const *) a, *(QTNode *const *) b); } +/* + * Canonicalize a QTNode tree by sorting the children of AND/OR nodes + * into an arbitrary but well-defined order. + */ void QTNSort(QTNode *in) { @@ -154,13 +171,16 @@ QTNSort(QTNode *in) qsort((void *) in->child, in->nchild, sizeof(QTNode *), cmpQTN); } +/* + * Are two QTNode trees equal according to QTNodeCompare? + */ bool QTNEq(QTNode *a, QTNode *b) { uint32 sign = a->sign & b->sign; if (!(sign == a->sign && sign == b->sign)) - return 0; + return false; return (QTNodeCompare(a, b) == 0) ? true : false; } @@ -186,11 +206,17 @@ QTNTernary(QTNode *in) for (i = 0; i < in->nchild; i++) QTNTernary(in->child[i]); + /* Only AND and OR are associative, so don't flatten other node types */ + if (in->valnode->qoperator.oper != OP_AND && + in->valnode->qoperator.oper != OP_OR) + return; + for (i = 0; i < in->nchild; i++) { QTNode *cc = in->child[i]; - if (cc->valnode->type == QI_OPR && in->valnode->qoperator.oper == cc->valnode->qoperator.oper) + if (cc->valnode->type == QI_OPR && + in->valnode->qoperator.oper == cc->valnode->qoperator.oper) { int oldnchild = in->nchild; @@ -229,9 +255,6 @@ QTNBinary(QTNode *in) for (i = 0; i < in->nchild; i++) QTNBinary(in->child[i]); - if (in->nchild <= 2) - return; - while (in->nchild > 2) { QTNode *nn = (QTNode *) palloc0(sizeof(QTNode)); @@ -256,8 +279,9 @@ QTNBinary(QTNode *in) } /* - * Count the total length of operand string in tree, including '\0'- - * terminators. + * Count the total length of operand strings in tree (including '\0'- + * terminators) and the total number of nodes. + * Caller must initialize *sumlen and *nnode to zeroes. */ static void cntsize(QTNode *in, int *sumlen, int *nnode) @@ -286,6 +310,10 @@ typedef struct char *curoperand; } QTN2QTState; +/* + * Recursively convert a QTNode tree into flat tsquery format. + * Caller must have allocated arrays of the correct size. + */ static void fillQT(QTN2QTState *state, QTNode *in) { @@ -323,6 +351,9 @@ fillQT(QTN2QTState *state, QTNode *in) } } +/* + * Build flat tsquery from a QTNode tree. + */ TSQuery QTN2QT(QTNode *in) { @@ -351,6 +382,11 @@ QTN2QT(QTNode *in) return out; } +/* + * Copy a QTNode tree. + * + * Modifiable copies of the words and valnodes are made, too. + */ QTNode * QTNCopy(QTNode *in) { @@ -386,6 +422,9 @@ QTNCopy(QTNode *in) return out; } +/* + * Clear the specified flag bit(s) in all nodes of a QTNode tree. + */ void QTNClearFlags(QTNode *in, uint32 flags) { diff --git a/src/test/regress/expected/tsearch.out b/src/test/regress/expected/tsearch.out index d22d345145..12af5a8897 100644 --- a/src/test/regress/expected/tsearch.out +++ b/src/test/regress/expected/tsearch.out @@ -865,6 +865,13 @@ SELECT ts_rewrite('foo & bar & qq & new & york', 'new & york'::tsquery, 'big & 'foo' & 'bar' & 'qq' & ( 'city' & 'new' & 'york' | ( 'nyc' | 'big' & 'apple' ) ) (1 row) +SELECT ts_rewrite(ts_rewrite('new & !york ', 'york', '!jersey'), + 'jersey', 'mexico'); + ts_rewrite +------------------------ + 'new' & !( !'mexico' ) +(1 row) + SELECT ts_rewrite('moscow', 'SELECT keyword, sample FROM test_tsquery'::text ); ts_rewrite --------------------- diff --git a/src/test/regress/sql/tsearch.sql b/src/test/regress/sql/tsearch.sql index fa460cd4b9..a40bc307ba 100644 --- a/src/test/regress/sql/tsearch.sql +++ b/src/test/regress/sql/tsearch.sql @@ -311,6 +311,8 @@ SELECT COUNT(*) FROM test_tsquery WHERE keyword > 'new & york'; RESET enable_seqscan; SELECT ts_rewrite('foo & bar & qq & new & york', 'new & york'::tsquery, 'big & apple | nyc | new & york & city'); +SELECT ts_rewrite(ts_rewrite('new & !york ', 'york', '!jersey'), + 'jersey', 'mexico'); SELECT ts_rewrite('moscow', 'SELECT keyword, sample FROM test_tsquery'::text ); SELECT ts_rewrite('moscow & hotel', 'SELECT keyword, sample FROM test_tsquery'::text );