mirror of
https://github.com/berkeleydb/libdb.git
synced 2024-11-17 01:26:25 +00:00
388 lines
15 KiB
C
388 lines
15 KiB
C
/*
|
|
** 2009 Nov 12
|
|
**
|
|
** The author disclaims copyright to this source code. In place of
|
|
** a legal notice, here is a blessing:
|
|
**
|
|
** May you do good and not evil.
|
|
** May you find forgiveness for yourself and forgive others.
|
|
** May you share freely, never taking more than you give.
|
|
**
|
|
******************************************************************************
|
|
**
|
|
*/
|
|
|
|
#ifndef _FTSINT_H
|
|
#define _FTSINT_H
|
|
|
|
#if !defined(NDEBUG) && !defined(SQLITE_DEBUG)
|
|
# define NDEBUG 1
|
|
#endif
|
|
|
|
#include "sqlite3.h"
|
|
#include "fts3_tokenizer.h"
|
|
#include "fts3_hash.h"
|
|
|
|
/*
|
|
** This constant controls how often segments are merged. Once there are
|
|
** FTS3_MERGE_COUNT segments of level N, they are merged into a single
|
|
** segment of level N+1.
|
|
*/
|
|
#define FTS3_MERGE_COUNT 16
|
|
|
|
/*
|
|
** This is the maximum amount of data (in bytes) to store in the
|
|
** Fts3Table.pendingTerms hash table. Normally, the hash table is
|
|
** populated as documents are inserted/updated/deleted in a transaction
|
|
** and used to create a new segment when the transaction is committed.
|
|
** However if this limit is reached midway through a transaction, a new
|
|
** segment is created and the hash table cleared immediately.
|
|
*/
|
|
#define FTS3_MAX_PENDING_DATA (1*1024*1024)
|
|
|
|
/*
|
|
** Macro to return the number of elements in an array. SQLite has a
|
|
** similar macro called ArraySize(). Use a different name to avoid
|
|
** a collision when building an amalgamation with built-in FTS3.
|
|
*/
|
|
#define SizeofArray(X) ((int)(sizeof(X)/sizeof(X[0])))
|
|
|
|
/*
|
|
** Maximum length of a varint encoded integer. The varint format is different
|
|
** from that used by SQLite, so the maximum length is 10, not 9.
|
|
*/
|
|
#define FTS3_VARINT_MAX 10
|
|
|
|
/*
|
|
** The testcase() macro is only used by the amalgamation. If undefined,
|
|
** make it a no-op.
|
|
*/
|
|
#ifndef testcase
|
|
# define testcase(X)
|
|
#endif
|
|
|
|
/*
|
|
** Terminator values for position-lists and column-lists.
|
|
*/
|
|
#define POS_COLUMN (1) /* Column-list terminator */
|
|
#define POS_END (0) /* Position-list terminator */
|
|
|
|
/*
|
|
** This section provides definitions to allow the
|
|
** FTS3 extension to be compiled outside of the
|
|
** amalgamation.
|
|
*/
|
|
#ifndef SQLITE_AMALGAMATION
|
|
/*
|
|
** Macros indicating that conditional expressions are always true or
|
|
** false.
|
|
*/
|
|
#ifdef SQLITE_COVERAGE_TEST
|
|
# define ALWAYS(x) (1)
|
|
# define NEVER(X) (0)
|
|
#else
|
|
# define ALWAYS(x) (x)
|
|
# define NEVER(X) (x)
|
|
#endif
|
|
|
|
/*
|
|
** Internal types used by SQLite.
|
|
*/
|
|
typedef unsigned char u8; /* 1-byte (or larger) unsigned integer */
|
|
typedef short int i16; /* 2-byte (or larger) signed integer */
|
|
typedef unsigned int u32; /* 4-byte unsigned integer */
|
|
typedef sqlite3_uint64 u64; /* 8-byte unsigned integer */
|
|
/*
|
|
** Macro used to suppress compiler warnings for unused parameters.
|
|
*/
|
|
#define UNUSED_PARAMETER(x) (void)(x)
|
|
#endif
|
|
|
|
typedef struct Fts3Table Fts3Table;
|
|
typedef struct Fts3Cursor Fts3Cursor;
|
|
typedef struct Fts3Expr Fts3Expr;
|
|
typedef struct Fts3Phrase Fts3Phrase;
|
|
typedef struct Fts3PhraseToken Fts3PhraseToken;
|
|
|
|
typedef struct Fts3SegFilter Fts3SegFilter;
|
|
typedef struct Fts3DeferredToken Fts3DeferredToken;
|
|
typedef struct Fts3SegReader Fts3SegReader;
|
|
typedef struct Fts3SegReaderCursor Fts3SegReaderCursor;
|
|
|
|
/*
|
|
** A connection to a fulltext index is an instance of the following
|
|
** structure. The xCreate and xConnect methods create an instance
|
|
** of this structure and xDestroy and xDisconnect free that instance.
|
|
** All other methods receive a pointer to the structure as one of their
|
|
** arguments.
|
|
*/
|
|
struct Fts3Table {
|
|
sqlite3_vtab base; /* Base class used by SQLite core */
|
|
sqlite3 *db; /* The database connection */
|
|
const char *zDb; /* logical database name */
|
|
const char *zName; /* virtual table name */
|
|
int nColumn; /* number of named columns in virtual table */
|
|
char **azColumn; /* column names. malloced */
|
|
sqlite3_tokenizer *pTokenizer; /* tokenizer for inserts and queries */
|
|
|
|
/* Precompiled statements used by the implementation. Each of these
|
|
** statements is run and reset within a single virtual table API call.
|
|
*/
|
|
sqlite3_stmt *aStmt[24];
|
|
|
|
char *zReadExprlist;
|
|
char *zWriteExprlist;
|
|
|
|
int nNodeSize; /* Soft limit for node size */
|
|
u8 bHasStat; /* True if %_stat table exists */
|
|
u8 bHasDocsize; /* True if %_docsize table exists */
|
|
int nPgsz; /* Page size for host database */
|
|
char *zSegmentsTbl; /* Name of %_segments table */
|
|
sqlite3_blob *pSegments; /* Blob handle open on %_segments table */
|
|
|
|
/* The following hash table is used to buffer pending index updates during
|
|
** transactions. Variable nPendingData estimates the memory size of the
|
|
** pending data, including hash table overhead, but not malloc overhead.
|
|
** When nPendingData exceeds nMaxPendingData, the buffer is flushed
|
|
** automatically. Variable iPrevDocid is the docid of the most recently
|
|
** inserted record.
|
|
*/
|
|
int nMaxPendingData;
|
|
int nPendingData;
|
|
sqlite_int64 iPrevDocid;
|
|
Fts3Hash pendingTerms;
|
|
};
|
|
|
|
/*
|
|
** When the core wants to read from the virtual table, it creates a
|
|
** virtual table cursor (an instance of the following structure) using
|
|
** the xOpen method. Cursors are destroyed using the xClose method.
|
|
*/
|
|
struct Fts3Cursor {
|
|
sqlite3_vtab_cursor base; /* Base class used by SQLite core */
|
|
i16 eSearch; /* Search strategy (see below) */
|
|
u8 isEof; /* True if at End Of Results */
|
|
u8 isRequireSeek; /* True if must seek pStmt to %_content row */
|
|
sqlite3_stmt *pStmt; /* Prepared statement in use by the cursor */
|
|
Fts3Expr *pExpr; /* Parsed MATCH query string */
|
|
int nPhrase; /* Number of matchable phrases in query */
|
|
Fts3DeferredToken *pDeferred; /* Deferred search tokens, if any */
|
|
sqlite3_int64 iPrevId; /* Previous id read from aDoclist */
|
|
char *pNextId; /* Pointer into the body of aDoclist */
|
|
char *aDoclist; /* List of docids for full-text queries */
|
|
int nDoclist; /* Size of buffer at aDoclist */
|
|
int eEvalmode; /* An FTS3_EVAL_XX constant */
|
|
int nRowAvg; /* Average size of database rows, in pages */
|
|
|
|
int isMatchinfoNeeded; /* True when aMatchinfo[] needs filling in */
|
|
u32 *aMatchinfo; /* Information about most recent match */
|
|
int nMatchinfo; /* Number of elements in aMatchinfo[] */
|
|
char *zMatchinfo; /* Matchinfo specification */
|
|
};
|
|
|
|
#define FTS3_EVAL_FILTER 0
|
|
#define FTS3_EVAL_NEXT 1
|
|
#define FTS3_EVAL_MATCHINFO 2
|
|
|
|
/*
|
|
** The Fts3Cursor.eSearch member is always set to one of the following.
|
|
** Actualy, Fts3Cursor.eSearch can be greater than or equal to
|
|
** FTS3_FULLTEXT_SEARCH. If so, then Fts3Cursor.eSearch - 2 is the index
|
|
** of the column to be searched. For example, in
|
|
**
|
|
** CREATE VIRTUAL TABLE ex1 USING fts3(a,b,c,d);
|
|
** SELECT docid FROM ex1 WHERE b MATCH 'one two three';
|
|
**
|
|
** Because the LHS of the MATCH operator is 2nd column "b",
|
|
** Fts3Cursor.eSearch will be set to FTS3_FULLTEXT_SEARCH+1. (+0 for a,
|
|
** +1 for b, +2 for c, +3 for d.) If the LHS of MATCH were "ex1"
|
|
** indicating that all columns should be searched,
|
|
** then eSearch would be set to FTS3_FULLTEXT_SEARCH+4.
|
|
*/
|
|
#define FTS3_FULLSCAN_SEARCH 0 /* Linear scan of %_content table */
|
|
#define FTS3_DOCID_SEARCH 1 /* Lookup by rowid on %_content table */
|
|
#define FTS3_FULLTEXT_SEARCH 2 /* Full-text index search */
|
|
|
|
/*
|
|
** A "phrase" is a sequence of one or more tokens that must match in
|
|
** sequence. A single token is the base case and the most common case.
|
|
** For a sequence of tokens contained in double-quotes (i.e. "one two three")
|
|
** nToken will be the number of tokens in the string.
|
|
**
|
|
** The nDocMatch and nMatch variables contain data that may be used by the
|
|
** matchinfo() function. They are populated when the full-text index is
|
|
** queried for hits on the phrase. If one or more tokens in the phrase
|
|
** are deferred, the nDocMatch and nMatch variables are populated based
|
|
** on the assumption that the
|
|
*/
|
|
struct Fts3PhraseToken {
|
|
char *z; /* Text of the token */
|
|
int n; /* Number of bytes in buffer z */
|
|
int isPrefix; /* True if token ends with a "*" character */
|
|
int bFulltext; /* True if full-text index was used */
|
|
Fts3SegReaderCursor *pSegcsr; /* Segment-reader for this token */
|
|
Fts3DeferredToken *pDeferred; /* Deferred token object for this token */
|
|
};
|
|
|
|
struct Fts3Phrase {
|
|
/* Variables populated by fts3_expr.c when parsing a MATCH expression */
|
|
int nToken; /* Number of tokens in the phrase */
|
|
int iColumn; /* Index of column this phrase must match */
|
|
int isNot; /* Phrase prefixed by unary not (-) operator */
|
|
Fts3PhraseToken aToken[1]; /* One entry for each token in the phrase */
|
|
};
|
|
|
|
/*
|
|
** A tree of these objects forms the RHS of a MATCH operator.
|
|
**
|
|
** If Fts3Expr.eType is either FTSQUERY_NEAR or FTSQUERY_PHRASE and isLoaded
|
|
** is true, then aDoclist points to a malloced buffer, size nDoclist bytes,
|
|
** containing the results of the NEAR or phrase query in FTS3 doclist
|
|
** format. As usual, the initial "Length" field found in doclists stored
|
|
** on disk is omitted from this buffer.
|
|
**
|
|
** Variable pCurrent always points to the start of a docid field within
|
|
** aDoclist. Since the doclist is usually scanned in docid order, this can
|
|
** be used to accelerate seeking to the required docid within the doclist.
|
|
*/
|
|
struct Fts3Expr {
|
|
int eType; /* One of the FTSQUERY_XXX values defined below */
|
|
int nNear; /* Valid if eType==FTSQUERY_NEAR */
|
|
Fts3Expr *pParent; /* pParent->pLeft==this or pParent->pRight==this */
|
|
Fts3Expr *pLeft; /* Left operand */
|
|
Fts3Expr *pRight; /* Right operand */
|
|
Fts3Phrase *pPhrase; /* Valid if eType==FTSQUERY_PHRASE */
|
|
|
|
int isLoaded; /* True if aDoclist/nDoclist are initialized. */
|
|
char *aDoclist; /* Buffer containing doclist */
|
|
int nDoclist; /* Size of aDoclist in bytes */
|
|
|
|
sqlite3_int64 iCurrent;
|
|
char *pCurrent;
|
|
};
|
|
|
|
/*
|
|
** Candidate values for Fts3Query.eType. Note that the order of the first
|
|
** four values is in order of precedence when parsing expressions. For
|
|
** example, the following:
|
|
**
|
|
** "a OR b AND c NOT d NEAR e"
|
|
**
|
|
** is equivalent to:
|
|
**
|
|
** "a OR (b AND (c NOT (d NEAR e)))"
|
|
*/
|
|
#define FTSQUERY_NEAR 1
|
|
#define FTSQUERY_NOT 2
|
|
#define FTSQUERY_AND 3
|
|
#define FTSQUERY_OR 4
|
|
#define FTSQUERY_PHRASE 5
|
|
|
|
|
|
/* fts3_write.c */
|
|
int sqlite3Fts3UpdateMethod(sqlite3_vtab*,int,sqlite3_value**,sqlite3_int64*);
|
|
int sqlite3Fts3PendingTermsFlush(Fts3Table *);
|
|
void sqlite3Fts3PendingTermsClear(Fts3Table *);
|
|
int sqlite3Fts3Optimize(Fts3Table *);
|
|
int sqlite3Fts3SegReaderNew(int, sqlite3_int64,
|
|
sqlite3_int64, sqlite3_int64, const char *, int, Fts3SegReader**);
|
|
int sqlite3Fts3SegReaderPending(Fts3Table*,const char*,int,int,Fts3SegReader**);
|
|
void sqlite3Fts3SegReaderFree(Fts3SegReader *);
|
|
int sqlite3Fts3SegReaderCost(Fts3Cursor *, Fts3SegReader *, int *);
|
|
int sqlite3Fts3AllSegdirs(Fts3Table*, int, sqlite3_stmt **);
|
|
int sqlite3Fts3ReadLock(Fts3Table *);
|
|
int sqlite3Fts3ReadBlock(Fts3Table*, sqlite3_int64, char **, int*);
|
|
|
|
int sqlite3Fts3SelectDoctotal(Fts3Table *, sqlite3_stmt **);
|
|
int sqlite3Fts3SelectDocsize(Fts3Table *, sqlite3_int64, sqlite3_stmt **);
|
|
|
|
void sqlite3Fts3FreeDeferredTokens(Fts3Cursor *);
|
|
int sqlite3Fts3DeferToken(Fts3Cursor *, Fts3PhraseToken *, int);
|
|
int sqlite3Fts3CacheDeferredDoclists(Fts3Cursor *);
|
|
void sqlite3Fts3FreeDeferredDoclists(Fts3Cursor *);
|
|
char *sqlite3Fts3DeferredDoclist(Fts3DeferredToken *, int *);
|
|
void sqlite3Fts3SegmentsClose(Fts3Table *);
|
|
|
|
#define FTS3_SEGCURSOR_PENDING -1
|
|
#define FTS3_SEGCURSOR_ALL -2
|
|
|
|
int sqlite3Fts3SegReaderStart(Fts3Table*, Fts3SegReaderCursor*, Fts3SegFilter*);
|
|
int sqlite3Fts3SegReaderStep(Fts3Table *, Fts3SegReaderCursor *);
|
|
void sqlite3Fts3SegReaderFinish(Fts3SegReaderCursor *);
|
|
int sqlite3Fts3SegReaderCursor(
|
|
Fts3Table *, int, const char *, int, int, int, Fts3SegReaderCursor *);
|
|
|
|
/* Flags allowed as part of the 4th argument to SegmentReaderIterate() */
|
|
#define FTS3_SEGMENT_REQUIRE_POS 0x00000001
|
|
#define FTS3_SEGMENT_IGNORE_EMPTY 0x00000002
|
|
#define FTS3_SEGMENT_COLUMN_FILTER 0x00000004
|
|
#define FTS3_SEGMENT_PREFIX 0x00000008
|
|
#define FTS3_SEGMENT_SCAN 0x00000010
|
|
|
|
/* Type passed as 4th argument to SegmentReaderIterate() */
|
|
struct Fts3SegFilter {
|
|
const char *zTerm;
|
|
int nTerm;
|
|
int iCol;
|
|
int flags;
|
|
};
|
|
|
|
struct Fts3SegReaderCursor {
|
|
/* Used internally by sqlite3Fts3SegReaderXXX() calls */
|
|
Fts3SegReader **apSegment; /* Array of Fts3SegReader objects */
|
|
int nSegment; /* Size of apSegment array */
|
|
int nAdvance; /* How many seg-readers to advance */
|
|
Fts3SegFilter *pFilter; /* Pointer to filter object */
|
|
char *aBuffer; /* Buffer to merge doclists in */
|
|
int nBuffer; /* Allocated size of aBuffer[] in bytes */
|
|
|
|
/* Cost of running this iterator. Used by fts3.c only. */
|
|
int nCost;
|
|
|
|
/* Output values. Valid only after Fts3SegReaderStep() returns SQLITE_ROW. */
|
|
char *zTerm; /* Pointer to term buffer */
|
|
int nTerm; /* Size of zTerm in bytes */
|
|
char *aDoclist; /* Pointer to doclist buffer */
|
|
int nDoclist; /* Size of aDoclist[] in bytes */
|
|
};
|
|
|
|
/* fts3.c */
|
|
int sqlite3Fts3PutVarint(char *, sqlite3_int64);
|
|
int sqlite3Fts3GetVarint(const char *, sqlite_int64 *);
|
|
int sqlite3Fts3GetVarint32(const char *, int *);
|
|
int sqlite3Fts3VarintLen(sqlite3_uint64);
|
|
void sqlite3Fts3Dequote(char *);
|
|
|
|
char *sqlite3Fts3FindPositions(Fts3Expr *, sqlite3_int64, int);
|
|
int sqlite3Fts3ExprLoadDoclist(Fts3Cursor *, Fts3Expr *);
|
|
int sqlite3Fts3ExprLoadFtDoclist(Fts3Cursor *, Fts3Expr *, char **, int *);
|
|
int sqlite3Fts3ExprNearTrim(Fts3Expr *, Fts3Expr *, int);
|
|
|
|
/* fts3_tokenizer.c */
|
|
const char *sqlite3Fts3NextToken(const char *, int *);
|
|
int sqlite3Fts3InitHashTable(sqlite3 *, Fts3Hash *, const char *);
|
|
int sqlite3Fts3InitTokenizer(Fts3Hash *pHash, const char *,
|
|
sqlite3_tokenizer **, char **
|
|
);
|
|
int sqlite3Fts3IsIdChar(char);
|
|
|
|
/* fts3_snippet.c */
|
|
void sqlite3Fts3Offsets(sqlite3_context*, Fts3Cursor*);
|
|
void sqlite3Fts3Snippet(sqlite3_context *, Fts3Cursor *, const char *,
|
|
const char *, const char *, int, int
|
|
);
|
|
void sqlite3Fts3Matchinfo(sqlite3_context *, Fts3Cursor *, const char *);
|
|
|
|
/* fts3_expr.c */
|
|
int sqlite3Fts3ExprParse(sqlite3_tokenizer *,
|
|
char **, int, int, const char *, int, Fts3Expr **
|
|
);
|
|
void sqlite3Fts3ExprFree(Fts3Expr *);
|
|
#ifdef SQLITE_TEST
|
|
int sqlite3Fts3ExprInitTestInterface(sqlite3 *db);
|
|
#endif
|
|
|
|
/* fts3_aux.c */
|
|
int sqlite3Fts3InitAux(sqlite3 *db);
|
|
|
|
#endif /* _FTSINT_H */
|