| Index: third_party/sqlite/src/ext/fts2/fts2_tokenizer.h
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| diff --git a/third_party/sqlite/src/ext/fts2/fts2_tokenizer.h b/third_party/sqlite/src/ext/fts2/fts2_tokenizer.h
|
| new file mode 100644
|
| index 0000000000000000000000000000000000000000..8c256b2bed3dae2c0f588fbd179bc6c4a1845407
|
| --- /dev/null
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| +++ b/third_party/sqlite/src/ext/fts2/fts2_tokenizer.h
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| @@ -0,0 +1,145 @@
|
| +/*
|
| +** 2006 July 10
|
| +**
|
| +** The author disclaims copyright to this source code.
|
| +**
|
| +*************************************************************************
|
| +** Defines the interface to tokenizers used by fulltext-search. There
|
| +** are three basic components:
|
| +**
|
| +** sqlite3_tokenizer_module is a singleton defining the tokenizer
|
| +** interface functions. This is essentially the class structure for
|
| +** tokenizers.
|
| +**
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| +** sqlite3_tokenizer is used to define a particular tokenizer, perhaps
|
| +** including customization information defined at creation time.
|
| +**
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| +** sqlite3_tokenizer_cursor is generated by a tokenizer to generate
|
| +** tokens from a particular input.
|
| +*/
|
| +#ifndef _FTS2_TOKENIZER_H_
|
| +#define _FTS2_TOKENIZER_H_
|
| +
|
| +/* TODO(shess) Only used for SQLITE_OK and SQLITE_DONE at this time.
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| +** If tokenizers are to be allowed to call sqlite3_*() functions, then
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| +** we will need a way to register the API consistently.
|
| +*/
|
| +#include "sqlite3.h"
|
| +
|
| +/*
|
| +** Structures used by the tokenizer interface. When a new tokenizer
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| +** implementation is registered, the caller provides a pointer to
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| +** an sqlite3_tokenizer_module containing pointers to the callback
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| +** functions that make up an implementation.
|
| +**
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| +** When an fts2 table is created, it passes any arguments passed to
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| +** the tokenizer clause of the CREATE VIRTUAL TABLE statement to the
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| +** sqlite3_tokenizer_module.xCreate() function of the requested tokenizer
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| +** implementation. The xCreate() function in turn returns an
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| +** sqlite3_tokenizer structure representing the specific tokenizer to
|
| +** be used for the fts2 table (customized by the tokenizer clause arguments).
|
| +**
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| +** To tokenize an input buffer, the sqlite3_tokenizer_module.xOpen()
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| +** method is called. It returns an sqlite3_tokenizer_cursor object
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| +** that may be used to tokenize a specific input buffer based on
|
| +** the tokenization rules supplied by a specific sqlite3_tokenizer
|
| +** object.
|
| +*/
|
| +typedef struct sqlite3_tokenizer_module sqlite3_tokenizer_module;
|
| +typedef struct sqlite3_tokenizer sqlite3_tokenizer;
|
| +typedef struct sqlite3_tokenizer_cursor sqlite3_tokenizer_cursor;
|
| +
|
| +struct sqlite3_tokenizer_module {
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| +
|
| + /*
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| + ** Structure version. Should always be set to 0.
|
| + */
|
| + int iVersion;
|
| +
|
| + /*
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| + ** Create a new tokenizer. The values in the argv[] array are the
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| + ** arguments passed to the "tokenizer" clause of the CREATE VIRTUAL
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| + ** TABLE statement that created the fts2 table. For example, if
|
| + ** the following SQL is executed:
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| + **
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| + ** CREATE .. USING fts2( ... , tokenizer <tokenizer-name> arg1 arg2)
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| + **
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| + ** then argc is set to 2, and the argv[] array contains pointers
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| + ** to the strings "arg1" and "arg2".
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| + **
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| + ** This method should return either SQLITE_OK (0), or an SQLite error
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| + ** code. If SQLITE_OK is returned, then *ppTokenizer should be set
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| + ** to point at the newly created tokenizer structure. The generic
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| + ** sqlite3_tokenizer.pModule variable should not be initialised by
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| + ** this callback. The caller will do so.
|
| + */
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| + int (*xCreate)(
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| + int argc, /* Size of argv array */
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| + const char *const*argv, /* Tokenizer argument strings */
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| + sqlite3_tokenizer **ppTokenizer /* OUT: Created tokenizer */
|
| + );
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| +
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| + /*
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| + ** Destroy an existing tokenizer. The fts2 module calls this method
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| + ** exactly once for each successful call to xCreate().
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| + */
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| + int (*xDestroy)(sqlite3_tokenizer *pTokenizer);
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| +
|
| + /*
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| + ** Create a tokenizer cursor to tokenize an input buffer. The caller
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| + ** is responsible for ensuring that the input buffer remains valid
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| + ** until the cursor is closed (using the xClose() method).
|
| + */
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| + int (*xOpen)(
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| + sqlite3_tokenizer *pTokenizer, /* Tokenizer object */
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| + const char *pInput, int nBytes, /* Input buffer */
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| + sqlite3_tokenizer_cursor **ppCursor /* OUT: Created tokenizer cursor */
|
| + );
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| +
|
| + /*
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| + ** Destroy an existing tokenizer cursor. The fts2 module calls this
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| + ** method exactly once for each successful call to xOpen().
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| + */
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| + int (*xClose)(sqlite3_tokenizer_cursor *pCursor);
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| +
|
| + /*
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| + ** Retrieve the next token from the tokenizer cursor pCursor. This
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| + ** method should either return SQLITE_OK and set the values of the
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| + ** "OUT" variables identified below, or SQLITE_DONE to indicate that
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| + ** the end of the buffer has been reached, or an SQLite error code.
|
| + **
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| + ** *ppToken should be set to point at a buffer containing the
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| + ** normalized version of the token (i.e. after any case-folding and/or
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| + ** stemming has been performed). *pnBytes should be set to the length
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| + ** of this buffer in bytes. The input text that generated the token is
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| + ** identified by the byte offsets returned in *piStartOffset and
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| + ** *piEndOffset.
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| + **
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| + ** The buffer *ppToken is set to point at is managed by the tokenizer
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| + ** implementation. It is only required to be valid until the next call
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| + ** to xNext() or xClose().
|
| + */
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| + /* TODO(shess) current implementation requires pInput to be
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| + ** nul-terminated. This should either be fixed, or pInput/nBytes
|
| + ** should be converted to zInput.
|
| + */
|
| + int (*xNext)(
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| + sqlite3_tokenizer_cursor *pCursor, /* Tokenizer cursor */
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| + const char **ppToken, int *pnBytes, /* OUT: Normalized text for token */
|
| + int *piStartOffset, /* OUT: Byte offset of token in input buffer */
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| + int *piEndOffset, /* OUT: Byte offset of end of token in input buffer */
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| + int *piPosition /* OUT: Number of tokens returned before this one */
|
| + );
|
| +};
|
| +
|
| +struct sqlite3_tokenizer {
|
| + const sqlite3_tokenizer_module *pModule; /* The module for this tokenizer */
|
| + /* Tokenizer implementations will typically add additional fields */
|
| +};
|
| +
|
| +struct sqlite3_tokenizer_cursor {
|
| + sqlite3_tokenizer *pTokenizer; /* Tokenizer for this cursor. */
|
| + /* Tokenizer implementations will typically add additional fields */
|
| +};
|
| +
|
| +#endif /* _FTS2_TOKENIZER_H_ */
|
|
|