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Diffstat (limited to 'include/mysql/plugin_ftparser.h')
| -rw-r--r-- | include/mysql/plugin_ftparser.h | 222 |
1 files changed, 222 insertions, 0 deletions
diff --git a/include/mysql/plugin_ftparser.h b/include/mysql/plugin_ftparser.h new file mode 100644 index 00000000..511b34bb --- /dev/null +++ b/include/mysql/plugin_ftparser.h @@ -0,0 +1,222 @@ +/* Copyright (c) 2005 MySQL AB, 2009 Sun Microsystems, Inc. + Use is subject to license terms. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; version 2 of the License. + + This program 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 General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335 USA */ + +#ifndef _my_plugin_ftparser_h +#define _my_plugin_ftparser_h +#include "plugin.h" + +#ifdef __cplusplus +extern "C" { +#endif + +/************************************************************************* + API for Full-text parser plugin. (MYSQL_FTPARSER_PLUGIN) +*/ + +#define MYSQL_FTPARSER_INTERFACE_VERSION 0x0100 + +/* Parsing modes. Set in MYSQL_FTPARSER_PARAM::mode */ +enum enum_ftparser_mode +{ +/* + Fast and simple mode. This mode is used for indexing, and natural + language queries. + + The parser is expected to return only those words that go into the + index. Stopwords or too short/long words should not be returned. The + 'boolean_info' argument of mysql_add_word() does not have to be set. +*/ + MYSQL_FTPARSER_SIMPLE_MODE= 0, + +/* + Parse with stopwords mode. This mode is used in boolean searches for + "phrase matching." + + The parser is not allowed to ignore words in this mode. Every word + should be returned, including stopwords and words that are too short + or long. The 'boolean_info' argument of mysql_add_word() does not + have to be set. +*/ + MYSQL_FTPARSER_WITH_STOPWORDS= 1, + +/* + Parse in boolean mode. This mode is used to parse a boolean query string. + + The parser should provide a valid MYSQL_FTPARSER_BOOLEAN_INFO + structure in the 'boolean_info' argument to mysql_add_word(). + Usually that means that the parser should recognize boolean operators + in the parsing stream and set appropriate fields in + MYSQL_FTPARSER_BOOLEAN_INFO structure accordingly. As for + MYSQL_FTPARSER_WITH_STOPWORDS mode, no word should be ignored. + Instead, use FT_TOKEN_STOPWORD for the token type of such a word. +*/ + MYSQL_FTPARSER_FULL_BOOLEAN_INFO= 2 +}; + +/* + Token types for boolean mode searching (used for the type member of + MYSQL_FTPARSER_BOOLEAN_INFO struct) + + FT_TOKEN_EOF: End of data. + FT_TOKEN_WORD: Regular word. + FT_TOKEN_LEFT_PAREN: Left parenthesis (start of group/sub-expression). + FT_TOKEN_RIGHT_PAREN: Right parenthesis (end of group/sub-expression). + FT_TOKEN_STOPWORD: Stopword. +*/ + +enum enum_ft_token_type +{ + FT_TOKEN_EOF= 0, + FT_TOKEN_WORD= 1, + FT_TOKEN_LEFT_PAREN= 2, + FT_TOKEN_RIGHT_PAREN= 3, + FT_TOKEN_STOPWORD= 4 +}; + +/* + This structure is used in boolean search mode only. It conveys + boolean-mode metadata to the MySQL search engine for every word in + the search query. A valid instance of this structure must be filled + in by the plugin parser and passed as an argument in the call to + mysql_add_word (the callback function in the MYSQL_FTPARSER_PARAM + structure) when a query is parsed in boolean mode. + + type: The token type. Should be one of the enum_ft_token_type values. + + yesno: Whether the word must be present for a match to occur: + >0 Must be present + <0 Must not be present + 0 Neither; the word is optional but its presence increases the relevance + With the default settings of the ft_boolean_syntax system variable, + >0 corresponds to the '+' operator, <0 corresponds to the '-' operator, + and 0 means neither operator was used. + + weight_adjust: A weighting factor that determines how much a match + for the word counts. Positive values increase, negative - decrease the + relative word's importance in the query. + + wasign: The sign of the word's weight in the query. If it's non-negative + the match for the word will increase document relevance, if it's + negative - decrease (the word becomes a "noise word", the less of it the + better). + + trunc: Corresponds to the '*' operator in the default setting of the + ft_boolean_syntax system variable. +*/ + +typedef struct st_mysql_ftparser_boolean_info +{ + enum enum_ft_token_type type; + int yesno; + int weight_adjust; + char wasign; + char trunc; + /* These are parser state and must be removed. */ + char prev; + char *quot; +} MYSQL_FTPARSER_BOOLEAN_INFO; + +/* + The following flag means that buffer with a string (document, word) + may be overwritten by the caller before the end of the parsing (that is + before st_mysql_ftparser::deinit() call). If one needs the string + to survive between two successive calls of the parsing function, she + needs to save a copy of it. The flag may be set by MySQL before calling + st_mysql_ftparser::parse(), or it may be set by a plugin before calling + st_mysql_ftparser_param::mysql_parse() or + st_mysql_ftparser_param::mysql_add_word(). +*/ +#define MYSQL_FTFLAGS_NEED_COPY 1 + +/* + An argument of the full-text parser plugin. This structure is + filled in by MySQL server and passed to the parsing function of the + plugin as an in/out parameter. + + mysql_parse: A pointer to the built-in parser implementation of the + server. It's set by the server and can be used by the parser plugin + to invoke the MySQL default parser. If plugin's role is to extract + textual data from .doc, .pdf or .xml content, it might extract + plaintext from the content, and then pass the text to the default + MySQL parser to be parsed. + + mysql_add_word: A server callback to add a new word. When parsing + a document, the server sets this to point at a function that adds + the word to MySQL full-text index. When parsing a search query, + this function will add the new word to the list of words to search + for. The boolean_info argument can be NULL for all cases except + when mode is MYSQL_FTPARSER_FULL_BOOLEAN_INFO. A plugin can replace this + callback to post-process every parsed word before passing it to the original + mysql_add_word function. + + ftparser_state: A generic pointer. The plugin can set it to point + to information to be used internally for its own purposes. + + mysql_ftparam: This is set by the server. It is used by MySQL functions + called via mysql_parse() and mysql_add_word() callback. The plugin + should not modify it. + + cs: Information about the character set of the document or query string. + + doc: A pointer to the document or query string to be parsed. + + length: Length of the document or query string, in bytes. + + flags: See MYSQL_FTFLAGS_* constants above. + + mode: The parsing mode. With boolean operators, with stopwords, or + nothing. See enum_ftparser_mode above. +*/ + +typedef struct st_mysql_ftparser_param +{ + int (*mysql_parse)(struct st_mysql_ftparser_param *, + const char *doc, int doc_len); + int (*mysql_add_word)(struct st_mysql_ftparser_param *, + const char *word, int word_len, + MYSQL_FTPARSER_BOOLEAN_INFO *boolean_info); + void *ftparser_state; + void *mysql_ftparam; + const struct charset_info_st *cs; + const char *doc; + int length; + unsigned int flags; + enum enum_ftparser_mode mode; +} MYSQL_FTPARSER_PARAM; + +/* + Full-text parser descriptor. + + interface_version is, e.g., MYSQL_FTPARSER_INTERFACE_VERSION. + The parsing, initialization, and deinitialization functions are + invoked per SQL statement for which the parser is used. +*/ + +struct st_mysql_ftparser +{ + int interface_version; + int (*parse)(MYSQL_FTPARSER_PARAM *param); + int (*init)(MYSQL_FTPARSER_PARAM *param); + int (*deinit)(MYSQL_FTPARSER_PARAM *param); +}; + + +#ifdef __cplusplus +} +#endif + +#endif + |