/* -*- c-basic-offset: 2 -*- */
/*
Copyright(C) 2012 Brazil
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License version 2.1 as published by the Free Software Foundation.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef GRN_PLUGIN_TOKENIZER_H
#define GRN_PLUGIN_TOKENIZER_H
#include <stddef.h>
#include <groonga/plugin.h>
#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */
#define GRN_TOKENIZER_TOKENIZED_DELIMITER_UTF8 "\xEF\xBF\xBE"
#define GRN_TOKENIZER_TOKENIZED_DELIMITER_UTF8_LEN 3
/*
grn_tokenizer_charlen() returns the length (#bytes) of the first character
in the string specified by `str_ptr' and `str_length'. If the starting bytes
are invalid as a character, grn_tokenizer_charlen() returns 0. See
grn_encoding in "groonga.h" for more details of `encoding'
*/
int grn_tokenizer_charlen(grn_ctx *ctx, const char *str_ptr,
unsigned int str_length, grn_encoding encoding);
/*
grn_tokenizer_isspace() returns the length (#bytes) of the first character
in the string specified by `str_ptr' and `str_length' if it is a space
character. Otherwise, grn_tokenizer_isspace() returns 0.
*/
int grn_tokenizer_isspace(grn_ctx *ctx, const char *str_ptr,
unsigned int str_length, grn_encoding encoding);
/*
grn_tokenizer_is_tokenized_delimiter() returns whether is the first
character in the string specified by `str_ptr' and `str_length' the
special tokenized delimiter character or not.
*/
grn_bool grn_tokenizer_is_tokenized_delimiter(grn_ctx *ctx,
const char *str_ptr,
unsigned int str_length,
grn_encoding encoding);
/*
grn_tokenizer_have_tokenized_delimiter() returns whether is there
the special delimiter character in the string specified by `str_ptr'
and `str_length' the special tokenized delimiter character or not.
*/
GRN_PLUGIN_EXPORT grn_bool grn_tokenizer_have_tokenized_delimiter(grn_ctx *ctx,
const char *str_ptr,
unsigned int str_length,
grn_encoding encoding);
/*
grn_tokenizer_query is a structure for storing a query. See the following
functions.
*/
typedef struct _grn_tokenizer_query grn_tokenizer_query;
struct _grn_tokenizer_query {
grn_obj *normalized_query;
char *query_buf;
const char *ptr;
unsigned int length;
grn_encoding encoding;
};
/*
grn_tokenizer_query_open() parses `args' and returns a new object of
grn_tokenizer_query. The new object stores information of the query.
grn_tokenizer_query_create() normalizes the query if the target table
requires normalization. grn_tokenizer_query_create() returns NULL if
something goes wrong. Note that grn_tokenizer_query_create() must be called
just once in the function that initializes a tokenizer.
*/
GRN_PLUGIN_EXPORT grn_tokenizer_query *grn_tokenizer_query_open(grn_ctx *ctx,
int num_args, grn_obj **args);
/*
grn_tokenizer_query_create() is deprecated. Use grn_tokenizer_query_open()
instead.
*/
grn_tokenizer_query *grn_tokenizer_query_create(grn_ctx *ctx,
int num_args, grn_obj **args);
/*
grn_tokenizer_query_close() finalizes an object of grn_tokenizer_query
and then frees memory allocated for that object.
*/
GRN_PLUGIN_EXPORT void grn_tokenizer_query_close(grn_ctx *ctx, grn_tokenizer_query *query);
/*
grn_tokenizer_query_destroy() is deprecated. Use grn_tokenizer_query_close()
instead.
*/
void grn_tokenizer_query_destroy(grn_ctx *ctx, grn_tokenizer_query *query);
/*
grn_tokenizer_token is needed to return tokens. A grn_tokenizer_token object
stores a token to be returned and it must be maintained until a request for
next token or finalization comes.
*/
typedef struct _grn_tokenizer_token grn_tokenizer_token;
struct _grn_tokenizer_token {
grn_obj str;
grn_obj status;
};
/*
grn_tokenizer_token_init() initializes `token'. Note that an initialized
object must be finalized by grn_tokenizer_token_fin().
*/
GRN_PLUGIN_EXPORT void grn_tokenizer_token_init(grn_ctx *ctx, grn_tokenizer_token *token);
/*
grn_tokenizer_token_fin() finalizes `token' that has been initialized by
grn_tokenizer_token_init().
*/
GRN_PLUGIN_EXPORT void grn_tokenizer_token_fin(grn_ctx *ctx, grn_tokenizer_token *token);
/*
grn_tokenizer_status provides a list of tokenizer status codes.
GRN_TOKENIZER_CONTINUE means that the next token is not the last one and
GRN_TOKENIZER_LAST means that the next token is the last one. If a document
or query contains no tokens, please push an empty string with
GRN_TOKENIZER_LAST as a token.
*/
typedef enum {
GRN_TOKENIZER_CONTINUE = 0,
GRN_TOKENIZER_LAST = 1
} grn_tokenizer_status;
/*
grn_tokenizer_token_push() pushes the next token into `token'. Note that
grn_tokenizer_token_push() does not make a copy of the given string. This
means that you have to maintain a memory space allocated to the string.
Also note that the grn_tokenizer_token object must be maintained until the
request for the next token or finalization comes. See grn_tokenizer_status in
this header for more details of `status'.
*/
GRN_PLUGIN_EXPORT void grn_tokenizer_token_push(grn_ctx *ctx, grn_tokenizer_token *token,
const char *str_ptr, unsigned int str_length,
grn_tokenizer_status status);
/*
grn_tokenizer_tokenized_delimiter_next() extracts the next token
from the string specified by `str_ptr' and `str_length' and pushes
the next token into `token'. It returns the string after the next
token. The returned string may be `NULL' when all tokens are
extracted.
*/
GRN_PLUGIN_EXPORT const char *grn_tokenizer_tokenized_delimiter_next(grn_ctx *ctx,
grn_tokenizer_token *token,
const char *str_ptr,
unsigned int str_length,
grn_encoding encoding);
/*
grn_tokenizer_register() registers a plugin to the database which is
associated with `ctx'. `plugin_name_ptr' and `plugin_name_length' specify the
plugin name. Alphabetic letters ('A'-'Z' and 'a'-'z'), digits ('0'-'9') and
an underscore ('_') are capable characters. `init', `next' and `fin' specify
the plugin functions. `init' is called for initializing a tokenizer for a
document or query. `next' is called for extracting tokens one by one. `fin'
is called for finalizing a tokenizer. grn_tokenizer_register() returns
GRN_SUCCESS on success, an error code on failure. See "groonga.h" for more
details of grn_proc_func and grn_user_data, that is used as an argument of
grn_proc_func.
*/
GRN_PLUGIN_EXPORT grn_rc grn_tokenizer_register(grn_ctx *ctx, const char *plugin_name_ptr,
unsigned int plugin_name_length,
grn_proc_func *init, grn_proc_func *next,
grn_proc_func *fin);
#ifdef __cplusplus
} /* extern "C" */
#endif /* __cplusplus */
#endif /* GRN_PLUGIN_TOKENIZER_H */