/* ** 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 */