diff options
Diffstat (limited to 'sql/sql_trigger.cc')
| -rw-r--r-- | sql/sql_trigger.cc | 286 |
1 files changed, 266 insertions, 20 deletions
diff --git a/sql/sql_trigger.cc b/sql/sql_trigger.cc index 0198dba780d..e33dc52df8f 100644 --- a/sql/sql_trigger.cc +++ b/sql/sql_trigger.cc @@ -65,7 +65,6 @@ File_option sql_modes_parameters= */ static const int TRG_NUM_REQUIRED_PARAMETERS= 4; -static const int TRG_MAX_VERSIONS= 3; /* Structure representing contents of .TRN file which are used to support @@ -318,8 +317,7 @@ bool Table_triggers_list::create_trigger(THD *thd, TABLE_LIST *tables, { LEX *lex= thd->lex; TABLE *table= tables->table; - char file_buff[FN_REFLEN], trigname_buff[FN_REFLEN], - trigname_path[FN_REFLEN]; + char file_buff[FN_REFLEN], trigname_buff[FN_REFLEN]; LEX_STRING file, trigname_file; LEX_STRING *trg_def, *name; ulonglong *trg_sql_mode; @@ -472,12 +470,11 @@ bool Table_triggers_list::create_trigger(THD *thd, TABLE_LIST *tables, definer_host->str, NullS) - trg_definer->str; if (!sql_create_definition_file(NULL, &file, &triggers_file_type, - (gptr)this, triggers_file_parameters, - TRG_MAX_VERSIONS)) + (gptr)this, triggers_file_parameters, 0)) return 0; err_with_cleanup: - my_delete(trigname_path, MYF(MY_WME)); + my_delete(trigname_buff, MYF(MY_WME)); return 1; } @@ -497,7 +494,8 @@ err_with_cleanup: True - error */ -static bool rm_trigger_file(char *path, char *db, char *table_name) +static bool rm_trigger_file(char *path, const char *db, + const char *table_name) { build_table_filename(path, FN_REFLEN-1, db, table_name, triggers_file_ext); return my_delete(path, MYF(MY_WME)); @@ -519,7 +517,8 @@ static bool rm_trigger_file(char *path, char *db, char *table_name) True - error */ -static bool rm_trigname_file(char *path, char *db, char *trigger_name) +static bool rm_trigname_file(char *path, const char *db, + const char *trigger_name) { build_table_filename(path, FN_REFLEN-1, db, trigger_name, trigname_file_ext); return my_delete(path, MYF(MY_WME)); @@ -527,6 +526,35 @@ static bool rm_trigname_file(char *path, char *db, char *trigger_name) /* + Helper function that saves .TRG file for Table_triggers_list object. + + SYNOPSIS + save_trigger_file() + triggers Table_triggers_list object for which file should be saved + db Name of database for subject table + table_name Name of subject table + + RETURN VALUE + FALSE Success + TRUE Error +*/ + +static bool save_trigger_file(Table_triggers_list *triggers, const char *db, + const char *table_name) +{ + char file_buff[FN_REFLEN]; + LEX_STRING file; + + file.length= build_table_filename(file_buff, FN_REFLEN-1, db, table_name, + triggers_file_ext); + file.str= file_buff; + return sql_create_definition_file(NULL, &file, &triggers_file_type, + (gptr)triggers, triggers_file_parameters, + 0); +} + + +/* Drop trigger for table. SYNOPSIS @@ -579,16 +607,7 @@ bool Table_triggers_list::drop_trigger(THD *thd, TABLE_LIST *tables) } else { - char file_buff[FN_REFLEN]; - LEX_STRING file; - - file.length= build_table_filename(file_buff, FN_REFLEN-1, - tables->db, tables->table_name, - triggers_file_ext); - file.str= file_buff; - if (sql_create_definition_file(NULL, &file, &triggers_file_type, - (gptr)this, triggers_file_parameters, - TRG_MAX_VERSIONS)) + if (save_trigger_file(this, tables->db, tables->table_name)) return 1; } @@ -827,12 +846,12 @@ bool Table_triggers_list::check_n_load(THD *thd, const char *db, if (!names_only && triggers->prepare_record1_accessors(table)) DBUG_RETURN(1); - char *trg_name_buff; List_iterator_fast<ulonglong> itm(triggers->definition_modes_list); List_iterator_fast<LEX_STRING> it_definer(triggers->definers_list); LEX *old_lex= thd->lex, lex; sp_rcontext *save_spcont= thd->spcont; ulong save_sql_mode= thd->variables.sql_mode; + LEX_STRING *on_table_name; thd->lex= &lex; @@ -898,6 +917,21 @@ bool Table_triggers_list::check_n_load(THD *thd, const char *db, &table->mem_root)) goto err_with_lex_cleanup; + if (!(on_table_name= (LEX_STRING*) alloc_root(&table->mem_root, + sizeof(LEX_STRING)))) + goto err_with_lex_cleanup; + *on_table_name= lex.ident; + if (triggers->on_table_names_list.push_back(on_table_name, &table->mem_root)) + goto err_with_lex_cleanup; + + /* + Let us check that we correctly update trigger definitions when we + rename tables with triggers. + */ + DBUG_ASSERT(!my_strcasecmp(table_alias_charset, lex.query_tables->db, db) && + !my_strcasecmp(table_alias_charset, lex.query_tables->table_name, + table_name)); + if (names_only) { lex_end(&lex); @@ -1063,7 +1097,7 @@ static TABLE_LIST *add_table_for_trigger(THD *thd, sp_name *trig) lex->query_tables= 0; lex->query_tables_last= &lex->query_tables; DBUG_RETURN(sp_add_to_query_tables(thd, lex, trig->m_db.str, - trigname.trigger_table.str, TL_WRITE)); + trigname.trigger_table.str, TL_IGNORE)); } @@ -1133,6 +1167,218 @@ end: } +/* + Update .TRG file after renaming triggers' subject table + (change name of table in triggers' definitions). + + SYNOPSIS + change_table_name_in_triggers() + thd Thread context + db_name Database of subject table + old_table_name Old subject table's name + new_table_name New subject table's name + + RETURN VALUE + FALSE Success + TRUE Failure +*/ + +bool +Table_triggers_list::change_table_name_in_triggers(THD *thd, + const char *db_name, + LEX_STRING *old_table_name, + LEX_STRING *new_table_name) +{ + char path_buff[FN_REFLEN]; + LEX_STRING *def, *on_table_name, new_def; + ulonglong *sql_mode; + ulong save_sql_mode= thd->variables.sql_mode; + List_iterator_fast<LEX_STRING> it_def(definitions_list); + List_iterator_fast<LEX_STRING> it_on_table_name(on_table_names_list); + List_iterator_fast<ulonglong> it_mode(definition_modes_list); + uint on_q_table_name_len, before_on_len; + String buff; + + DBUG_ASSERT(definitions_list.elements == on_table_names_list.elements && + definitions_list.elements == definition_modes_list.elements); + + while ((def= it_def++)) + { + on_table_name= it_on_table_name++; + thd->variables.sql_mode= *(it_mode++); + + /* Construct CREATE TRIGGER statement with new table name. */ + buff.length(0); + before_on_len= on_table_name->str - def->str; + buff.append(def->str, before_on_len); + buff.append(STRING_WITH_LEN("ON ")); + append_identifier(thd, &buff, new_table_name->str, new_table_name->length); + on_q_table_name_len= buff.length() - before_on_len; + buff.append(on_table_name->str + on_table_name->length, + def->length - (before_on_len + on_table_name->length)); + /* + It is OK to allocate some memory on table's MEM_ROOT since this + table instance will be thrown out at the end of rename anyway. + */ + new_def.str= memdup_root(&table->mem_root, buff.ptr(), buff.length()); + new_def.length= buff.length(); + on_table_name->str= new_def.str + before_on_len; + on_table_name->length= on_q_table_name_len; + *def= new_def; + } + + thd->variables.sql_mode= save_sql_mode; + + if (thd->is_fatal_error) + return TRUE; /* OOM */ + + if (save_trigger_file(this, db_name, new_table_name->str)) + return TRUE; + if (rm_trigger_file(path_buff, db_name, old_table_name->str)) + { + (void) rm_trigger_file(path_buff, db_name, new_table_name->str); + return TRUE; + } + return FALSE; +} + + +/* + Iterate though Table_triggers_list::names_list list and update .TRN files + after renaming triggers' subject table. + + SYNOPSIS + change_table_name_in_trignames() + db_name Database of subject table + new_table_name New subject table's name + stopper Pointer to Table_triggers_list::names_list at + which we should stop updating. + + RETURN VALUE + 0 Success + non-0 Failure, pointer to Table_triggers_list::names_list element + for which update failed. +*/ + +LEX_STRING* +Table_triggers_list::change_table_name_in_trignames(const char *db_name, + LEX_STRING *new_table_name, + LEX_STRING *stopper) +{ + char trigname_buff[FN_REFLEN]; + struct st_trigname trigname; + LEX_STRING trigname_file; + LEX_STRING *trigger; + List_iterator_fast<LEX_STRING> it_name(names_list); + + while ((trigger= it_name++) != stopper) + { + trigname_file.length= build_table_filename(trigname_buff, FN_REFLEN-1, + db_name, trigger->str, + trigname_file_ext); + trigname_file.str= trigname_buff; + + trigname.trigger_table= *new_table_name; + + if (sql_create_definition_file(NULL, &trigname_file, &trigname_file_type, + (gptr)&trigname, trigname_file_parameters, + 0)) + return trigger; + } + + return 0; +} + + +/* + Update .TRG and .TRN files after renaming triggers' subject table. + + SYNOPSIS + change_table_name() + thd Thread context + db Old database of subject table + old_table Old name of subject table + new_db New database for subject table + new_table New name of subject table + + NOTE + This method tries to leave trigger related files in consistent state, + i.e. it either will complete successfully, or will fail leaving files + in their initial state. + + RETURN VALUE + FALSE Success + TRUE Error +*/ + +bool Table_triggers_list::change_table_name(THD *thd, const char *db, + const char *old_table, + const char *new_db, + const char *new_table) +{ + TABLE table; + bool result= 0; + LEX_STRING *err_trigname; + DBUG_ENTER("change_table_name"); + + bzero(&table, sizeof(table)); + init_alloc_root(&table.mem_root, 8192, 0); + + safe_mutex_assert_owner(&LOCK_open); + + if (Table_triggers_list::check_n_load(thd, db, old_table, &table, TRUE)) + { + result= 1; + goto end; + } + if (table.triggers) + { + LEX_STRING_WITH_INIT old_table_name(old_table, strlen(old_table)); + LEX_STRING_WITH_INIT new_table_name(new_table, strlen(new_table)); + /* + Since triggers should be in the same schema as their subject tables + moving table with them between two schemas raises too many questions. + (E.g. what should happen if in new schema we already have trigger + with same name ?). + */ + if (my_strcasecmp(table_alias_charset, db, new_db)) + { + my_error(ER_TRG_IN_WRONG_SCHEMA, MYF(0)); + result= 1; + goto end; + } + if (table.triggers->change_table_name_in_triggers(thd, db, + &old_table_name, + &new_table_name)) + { + result= 1; + goto end; + } + if ((err_trigname= table.triggers->change_table_name_in_trignames( + db, &new_table_name, 0))) + { + /* + If we were unable to update one of .TRN files properly we will + revert all changes that we have done and report about error. + We assume that we will be able to undo our changes without errors + (we can't do much if there will be an error anyway). + */ + (void) table.triggers->change_table_name_in_trignames(db, + &old_table_name, + err_trigname); + (void) table.triggers->change_table_name_in_triggers(thd, db, + &new_table_name, + &old_table_name); + result= 1; + goto end; + } + } +end: + delete table.triggers; + free_root(&table.mem_root, MYF(0)); + DBUG_RETURN(result); +} + bool Table_triggers_list::process_triggers(THD *thd, trg_event_type event, trg_action_time_type time_type, |