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+#ifndef SQL_TRIGGER_INCLUDED
+#define SQL_TRIGGER_INCLUDED
+
+/*
+ Copyright (c) 2004, 2011, Oracle and/or its affiliates.
+ Copyright (c) 2017, MariaDB Corporation.
+
+ 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 */
+
+#include <mysqld_error.h>
+
+/* Forward declarations */
+
+class Item_trigger_field;
+class sp_head;
+class sp_name;
+class Query_tables_list;
+struct TABLE_LIST;
+class Query_tables_list;
+
+/** Event on which trigger is invoked. */
+enum trg_event_type
+{
+ TRG_EVENT_INSERT= 0,
+ TRG_EVENT_UPDATE= 1,
+ TRG_EVENT_DELETE= 2,
+ TRG_EVENT_MAX
+};
+
+static inline uint8 trg2bit(enum trg_event_type trg)
+{ return static_cast<uint8>(1 << static_cast<int>(trg)); }
+
+#include "table.h" /* GRANT_INFO */
+
+/*
+ We need this two enums here instead of sql_lex.h because
+ at least one of them is used by Item_trigger_field interface.
+
+ Time when trigger is invoked (i.e. before or after row actually
+ inserted/updated/deleted).
+*/
+enum trg_action_time_type
+{
+ TRG_ACTION_BEFORE= 0, TRG_ACTION_AFTER= 1, TRG_ACTION_MAX
+};
+
+enum trigger_order_type
+{
+ TRG_ORDER_NONE= 0,
+ TRG_ORDER_FOLLOWS= 1,
+ TRG_ORDER_PRECEDES= 2
+};
+
+
+struct st_trg_execution_order
+{
+ /**
+ FOLLOWS or PRECEDES as specified in the CREATE TRIGGER statement.
+ */
+ enum trigger_order_type ordering_clause;
+
+ /**
+ Trigger name referenced in the FOLLOWS/PRECEDES clause of the
+ CREATE TRIGGER statement.
+ */
+ LEX_CSTRING anchor_trigger_name;
+};
+
+
+class Table_triggers_list;
+
+/**
+ The trigger object
+*/
+
+class Trigger :public Sql_alloc
+{
+public:
+ Trigger(Table_triggers_list *base_arg, sp_head *code):
+ base(base_arg), body(code), next(0), trigger_fields(0), action_order(0)
+ {
+ bzero((char *)&subject_table_grants, sizeof(subject_table_grants));
+ }
+ ~Trigger();
+ Table_triggers_list *base;
+ sp_head *body;
+ Trigger *next; /* Next trigger of same type */
+
+ /**
+ Heads of the lists linking items for all fields used in triggers
+ grouped by event and action_time.
+ */
+ Item_trigger_field *trigger_fields;
+ LEX_CSTRING name;
+ LEX_CSTRING on_table_name; /* Raw table name */
+ LEX_CSTRING definition;
+ LEX_CSTRING definer;
+
+ /* Character sets used */
+ LEX_CSTRING client_cs_name;
+ LEX_CSTRING connection_cl_name;
+ LEX_CSTRING db_cl_name;
+
+ GRANT_INFO subject_table_grants;
+ sql_mode_t sql_mode;
+ /* Store create time. Can't be mysql_time_t as this holds also sub seconds */
+ ulonglong create_time;
+ trg_event_type event;
+ trg_action_time_type action_time;
+ uint action_order;
+
+ bool is_fields_updated_in_trigger(MY_BITMAP *used_fields);
+ void get_trigger_info(LEX_CSTRING *stmt, LEX_CSTRING *body,
+ LEX_STRING *definer);
+ /* Functions executed over each active trigger */
+ bool change_on_table_name(void* param_arg);
+ bool change_table_name(void* param_arg);
+ bool add_to_file_list(void* param_arg);
+};
+
+typedef bool (Trigger::*Triggers_processor)(void *arg);
+
+/**
+ This class holds all information about triggers of table.
+*/
+
+class Table_triggers_list: public Sql_alloc
+{
+ friend class Trigger;
+
+ /* Points to first trigger for a certain type */
+ Trigger *triggers[TRG_EVENT_MAX][TRG_ACTION_MAX];
+ /**
+ Copy of TABLE::Field array which all fields made nullable
+ (using extra_null_bitmap, if needed). Used for NEW values in
+ BEFORE INSERT/UPDATE triggers.
+ */
+ Field **record0_field;
+ uchar *extra_null_bitmap;
+ /**
+ 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;
+
+ /**
+ 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];
+ uint count; /* Number of triggers */
+
+public:
+ /**
+ Field responsible for storing triggers definitions in file.
+ It have to be public because we are using it directly from parser.
+ */
+ List<LEX_CSTRING> definitions_list;
+ /**
+ List of sql modes for triggers
+ */
+ List<ulonglong> definition_modes_list;
+ /** Create times for triggers */
+ List<ulonglong> create_times;
+
+ List<LEX_CSTRING> definers_list;
+
+ /* Character set context, used for parsing and executing triggers. */
+
+ List<LEX_CSTRING> client_cs_names;
+ List<LEX_CSTRING> connection_cl_names;
+ List<LEX_CSTRING> db_cl_names;
+
+ /* End of character ser context. */
+
+ Table_triggers_list(TABLE *table_arg)
+ :record0_field(0), extra_null_bitmap(0), record1_field(0),
+ trigger_table(table_arg),
+ m_has_unparseable_trigger(false), count(0)
+ {
+ bzero((char *) triggers, sizeof(triggers));
+ }
+ ~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);
+ void empty_lists();
+ bool create_lists_needed_for_files(MEM_ROOT *root);
+ bool save_trigger_file(THD *thd, const LEX_CSTRING *db, const LEX_CSTRING *table_name);
+
+ static bool check_n_load(THD *thd, const LEX_CSTRING *db, const LEX_CSTRING *table_name,
+ TABLE *table, bool names_only);
+ static bool drop_all_triggers(THD *thd, const LEX_CSTRING *db,
+ const LEX_CSTRING *table_name, myf MyFlags);
+ static bool change_table_name(THD *thd, const LEX_CSTRING *db,
+ const LEX_CSTRING *old_alias,
+ const LEX_CSTRING *old_table,
+ const LEX_CSTRING *new_db,
+ const LEX_CSTRING *new_table);
+ void add_trigger(trg_event_type event_type,
+ trg_action_time_type action_time,
+ trigger_order_type ordering_clause,
+ LEX_CSTRING *anchor_trigger_name,
+ Trigger *trigger);
+ Trigger *get_trigger(trg_event_type event_type,
+ trg_action_time_type action_time)
+ {
+ return triggers[event_type][action_time];
+ }
+ /* Simpler version of the above, to avoid casts in the code */
+ Trigger *get_trigger(uint event_type, uint action_time)
+ {
+ return get_trigger((trg_event_type) event_type,
+ (trg_action_time_type) action_time);
+ }
+
+ bool has_triggers(trg_event_type event_type,
+ trg_action_time_type action_time)
+ {
+ return get_trigger(event_type,action_time) != 0;
+ }
+ bool has_delete_triggers()
+ {
+ return (has_triggers(TRG_EVENT_DELETE,TRG_ACTION_BEFORE) ||
+ has_triggers(TRG_EVENT_DELETE,TRG_ACTION_AFTER));
+ }
+
+ void mark_fields_used(trg_event_type event);
+
+ void set_parse_error_message(char *error_message);
+
+ friend class Item_trigger_field;
+
+ bool add_tables_and_routines_for_triggers(THD *thd,
+ Query_tables_list *prelocking_ctx,
+ TABLE_LIST *table_list);
+
+ Field **nullable_fields() { return record0_field; }
+ void reset_extra_null_bitmap()
+ {
+ size_t null_bytes= (trigger_table->s->fields -
+ trigger_table->s->null_fields + 7)/8;
+ bzero(extra_null_bitmap, null_bytes);
+ }
+
+ Trigger *find_trigger(const LEX_CSTRING *name, bool remove_from_list);
+
+ Trigger* for_all_triggers(Triggers_processor func, void *arg);
+
+private:
+ bool prepare_record_accessors(TABLE *table);
+ Trigger *change_table_name_in_trignames(const LEX_CSTRING *old_db_name,
+ const LEX_CSTRING *new_db_name,
+ const LEX_CSTRING *new_table_name,
+ Trigger *trigger);
+ bool change_table_name_in_triggers(THD *thd,
+ const LEX_CSTRING *old_db_name,
+ const LEX_CSTRING *new_db_name,
+ const LEX_CSTRING *old_table_name,
+ const LEX_CSTRING *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;
+ }
+};
+
+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_CSTRING *trn_path);
+
+bool load_table_name_for_trigger(THD *thd,
+ const sp_name *trg_name,
+ const LEX_CSTRING *trn_path,
+ LEX_CSTRING *tbl_name);
+bool mysql_create_or_drop_trigger(THD *thd, TABLE_LIST *tables, bool create);
+
+extern const char * const TRG_EXT;
+extern const char * const TRN_EXT;
+
+#endif /* SQL_TRIGGER_INCLUDED */