/* Copyright (c) 2004, 2011, Oracle and/or its affiliates. All rights reserved. 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 02110-1301 USA */ /** This class holds all information about triggers of table. QQ: Will it be merged into TABLE in the future ? */ class Table_triggers_list: public Sql_alloc { /** Triggers as SPs grouped by event, action_time */ sp_head *bodies[TRG_EVENT_MAX][TRG_ACTION_MAX]; /** Heads of the lists linking items for all fields used in triggers grouped by event and action_time. */ Item_trigger_field *trigger_fields[TRG_EVENT_MAX][TRG_ACTION_MAX]; /** Copy of TABLE::Field array with field pointers set to TABLE::record[1] buffer instead of TABLE::record[0] (used for OLD values in on UPDATE trigger and DELETE trigger when it is called for REPLACE). */ Field **record1_field; /** During execution of trigger new_field and old_field should point to the array of fields representing new or old version of row correspondingly (so it can point to TABLE::field or to Tale_triggers_list::record1_field) */ Field **new_field; Field **old_field; /* TABLE instance for which this triggers list object was created */ TABLE *trigger_table; /** Names of triggers. Should correspond to order of triggers on definitions_list, used in CREATE/DROP TRIGGER for looking up trigger by name. */ List names_list; /** List of "ON table_name" parts in trigger definitions, used for updating trigger definitions during RENAME TABLE. */ List on_table_names_list; /** Grant information for each trigger (pair: subject table, trigger definer). */ GRANT_INFO subject_table_grants[TRG_EVENT_MAX][TRG_ACTION_MAX]; /** This flag indicates that one of the triggers was not parsed successfully, and as a precaution the object has entered a state where all trigger access results in errors until all such triggers are dropped. It is not safe to add triggers since we don't know if the broken trigger has the same name or event type. Nor is it safe to invoke any trigger for the aforementioned reasons. The only safe operations are drop_trigger and drop_all_triggers. @see Table_triggers_list::set_parse_error */ bool m_has_unparseable_trigger; /** This error will be displayed when the user tries to manipulate or invoke triggers on a table that has broken triggers. It will get set only once per statement and thus will contain the first parse error encountered in the trigger file. */ char m_parse_error_message[MYSQL_ERRMSG_SIZE]; public: /** Field responsible for storing triggers definitions in file. It have to be public because we are using it directly from parser. */ List definitions_list; /** List of sql modes for triggers */ List definition_modes_list; List definers_list; /* Character set context, used for parsing and executing triggers. */ List client_cs_names; List connection_cl_names; List db_cl_names; /* End of character ser context. */ Table_triggers_list(TABLE *table_arg): record1_field(0), trigger_table(table_arg), m_has_unparseable_trigger(false) { bzero((char *)bodies, sizeof(bodies)); bzero((char *)trigger_fields, sizeof(trigger_fields)); bzero((char *)&subject_table_grants, sizeof(subject_table_grants)); } ~Table_triggers_list(); bool create_trigger(THD *thd, TABLE_LIST *table, String *stmt_query); bool drop_trigger(THD *thd, TABLE_LIST *table, String *stmt_query); bool process_triggers(THD *thd, trg_event_type event, trg_action_time_type time_type, bool old_row_is_record1); bool get_trigger_info(THD *thd, trg_event_type event, trg_action_time_type time_type, LEX_STRING *trigger_name, LEX_STRING *trigger_stmt, ulong *sql_mode, LEX_STRING *definer, LEX_STRING *client_cs_name, LEX_STRING *connection_cl_name, LEX_STRING *db_cl_name); void get_trigger_info(THD *thd, int trigger_idx, LEX_STRING *trigger_name, ulonglong *sql_mode, LEX_STRING *sql_original_stmt, LEX_STRING *client_cs_name, LEX_STRING *connection_cl_name, LEX_STRING *db_cl_name); int find_trigger_by_name(const LEX_STRING *trigger_name); static bool check_n_load(THD *thd, const char *db, const char *table_name, TABLE *table, bool names_only); static bool drop_all_triggers(THD *thd, char *db, char *table_name); static bool change_table_name(THD *thd, const char *db, const char *old_table, const char *new_db, const char *new_table); bool has_triggers(trg_event_type event_type, trg_action_time_type action_time) { return (bodies[event_type][action_time] != NULL); } bool has_delete_triggers() { return (bodies[TRG_EVENT_DELETE][TRG_ACTION_BEFORE] || bodies[TRG_EVENT_DELETE][TRG_ACTION_AFTER]); } void set_table(TABLE *new_table); void mark_fields_used(trg_event_type event); void set_parse_error_message(char *error_message); friend class Item_trigger_field; friend int sp_cache_routines_and_add_tables_for_triggers(THD *thd, LEX *lex, TABLE_LIST *table); private: bool prepare_record1_accessors(TABLE *table); LEX_STRING* change_table_name_in_trignames(const char *old_db_name, const char *new_db_name, LEX_STRING *new_table_name, LEX_STRING *stopper); bool change_table_name_in_triggers(THD *thd, const char *old_db_name, const char *new_db_name, LEX_STRING *old_table_name, LEX_STRING *new_table_name); bool check_for_broken_triggers() { if (m_has_unparseable_trigger) { my_message(ER_PARSE_ERROR, m_parse_error_message, MYF(0)); return true; } return false; } }; extern const LEX_STRING trg_action_time_type_names[]; extern const LEX_STRING trg_event_type_names[]; bool add_table_for_trigger(THD *thd, const sp_name *trg_name, bool continue_if_not_exist, TABLE_LIST **table); void build_trn_path(THD *thd, const sp_name *trg_name, LEX_STRING *trn_path); bool check_trn_exists(const LEX_STRING *trn_path); bool load_table_name_for_trigger(THD *thd, const sp_name *trg_name, const LEX_STRING *trn_path, LEX_STRING *tbl_name);