/* Copyright (C) 2004-2005 MySQL AB 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; either version 2 of the License, or (at your option) any later version. 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ #define MYSQL_LEX 1 #include "mysql_priv.h" #include "sp_head.h" #include "sql_trigger.h" #include "parse_file.h" static const LEX_STRING triggers_file_type= { C_STRING_WITH_LEN("TRIGGERS") }; const char * const triggers_file_ext= ".TRG"; /* Table of .TRG file field descriptors. We have here only one field now because in nearest future .TRG files will be merged into .FRM files (so we don't need something like md5 or created fields). */ static File_option triggers_file_parameters[]= { { { C_STRING_WITH_LEN("triggers") }, offsetof(class Table_triggers_list, definitions_list), FILE_OPTIONS_STRLIST }, { { C_STRING_WITH_LEN("sql_modes") }, offsetof(class Table_triggers_list, definition_modes_list), FILE_OPTIONS_ULLLIST }, { { C_STRING_WITH_LEN("definers") }, offsetof(class Table_triggers_list, definers_list), FILE_OPTIONS_STRLIST }, { { 0, 0 }, 0, FILE_OPTIONS_STRING } }; File_option sql_modes_parameters= { { C_STRING_WITH_LEN("sql_modes") }, offsetof(class Table_triggers_list, definition_modes_list), FILE_OPTIONS_ULLLIST }; /* This must be kept up to date whenever a new option is added to the list above, as it specifies the number of required parameters of the trigger in .trg file. */ static const int TRG_NUM_REQUIRED_PARAMETERS= 4; /* Structure representing contents of .TRN file which are used to support database wide trigger namespace. */ struct st_trigname { LEX_STRING trigger_table; }; static const LEX_STRING trigname_file_type= { C_STRING_WITH_LEN("TRIGGERNAME") }; const char * const trigname_file_ext= ".TRN"; static File_option trigname_file_parameters[]= { { { C_STRING_WITH_LEN("trigger_table")}, offsetof(struct st_trigname, trigger_table), FILE_OPTIONS_ESTRING }, { { 0, 0 }, 0, FILE_OPTIONS_STRING } }; const LEX_STRING trg_action_time_type_names[]= { { C_STRING_WITH_LEN("BEFORE") }, { C_STRING_WITH_LEN("AFTER") } }; const LEX_STRING trg_event_type_names[]= { { C_STRING_WITH_LEN("INSERT") }, { C_STRING_WITH_LEN("UPDATE") }, { C_STRING_WITH_LEN("DELETE") } }; static TABLE_LIST *add_table_for_trigger(THD *thd, sp_name *trig); class Handle_old_incorrect_sql_modes_hook: public Unknown_key_hook { private: char *path; public: Handle_old_incorrect_sql_modes_hook(char *file_path) :path(file_path) {}; virtual bool process_unknown_string(char *&unknown_key, gptr base, MEM_ROOT *mem_root, char *end); }; class Handle_old_incorrect_trigger_table_hook: public Unknown_key_hook { public: Handle_old_incorrect_trigger_table_hook(char *file_path, LEX_STRING *trigger_table_arg) :path(file_path), trigger_table_value(trigger_table_arg) {}; virtual bool process_unknown_string(char *&unknown_key, gptr base, MEM_ROOT *mem_root, char *end); private: char *path; LEX_STRING *trigger_table_value; }; /* Create or drop trigger for table. SYNOPSIS mysql_create_or_drop_trigger() thd - current thread context (including trigger definition in LEX) tables - table list containing one table for which trigger is created. create - whenever we create (TRUE) or drop (FALSE) trigger NOTE This function is mainly responsible for opening and locking of table and invalidation of all its instances in table cache after trigger creation. Real work on trigger creation/dropping is done inside Table_triggers_list methods. RETURN VALUE FALSE Success TRUE error */ bool mysql_create_or_drop_trigger(THD *thd, TABLE_LIST *tables, bool create) { TABLE *table; bool result= TRUE; String stmt_query; DBUG_ENTER("mysql_create_or_drop_trigger"); /* Charset of the buffer for statement must be system one. */ stmt_query.set_charset(system_charset_info); /* QQ: This function could be merged in mysql_alter_table() function But do we want this ? */ /* Note that once we will have check for TRIGGER privilege in place we won't need second part of condition below, since check_access() function also checks that db is specified. */ if (!thd->lex->spname->m_db.length || create && !tables->db_length) { my_error(ER_NO_DB_ERROR, MYF(0)); DBUG_RETURN(TRUE); } if (!create && !(tables= add_table_for_trigger(thd, thd->lex->spname))) DBUG_RETURN(TRUE); /* We don't allow creating triggers on tables in the 'mysql' schema */ if (create && !my_strcasecmp(system_charset_info, "mysql", tables->db)) { my_error(ER_NO_TRIGGERS_ON_SYSTEM_SCHEMA, MYF(0)); DBUG_RETURN(TRUE); } /* We should have only one table in table list. */ DBUG_ASSERT(tables->next_global == 0); /* Check that the user has TRIGGER privilege on the subject table. */ { bool err_status; TABLE_LIST **save_query_tables_own_last= thd->lex->query_tables_own_last; thd->lex->query_tables_own_last= 0; err_status= check_table_access(thd, TRIGGER_ACL, tables, 0); thd->lex->query_tables_own_last= save_query_tables_own_last; if (err_status) DBUG_RETURN(TRUE); } /* There is no DETERMINISTIC clause for triggers, so can't check it. But a trigger can in theory be used to do nasty things (if it supported DROP for example) so we do the check for privileges. Triggers have the same nature as functions regarding binlogging: their body is implicitely binlogged, so they share the same danger, so trust_function_creators applies to them too. */ if (!trust_function_creators && mysql_bin_log.is_open() && !(thd->security_ctx->master_access & SUPER_ACL)) { my_error(ER_BINLOG_CREATE_ROUTINE_NEED_SUPER, MYF(0)); DBUG_RETURN(TRUE); } /* We do not allow creation of triggers on temporary tables. */ if (create && find_temporary_table(thd, tables)) { my_error(ER_TRG_ON_VIEW_OR_TEMP_TABLE, MYF(0), tables->alias); DBUG_RETURN(TRUE); } /* We don't want perform our operations while global read lock is held so we have to wait until its end and then prevent it from occuring again until we are done. (Acquiring LOCK_open is not enough because global read lock is held without helding LOCK_open). */ if (wait_if_global_read_lock(thd, 0, 1)) DBUG_RETURN(TRUE); VOID(pthread_mutex_lock(&LOCK_open)); if (lock_table_names(thd, tables)) goto end; /* We also don't allow creation of triggers on views. */ tables->required_type= FRMTYPE_TABLE; if (reopen_name_locked_table(thd, tables)) { unlock_table_name(thd, tables); goto end; } table= tables->table; if (!table->triggers) { if (!create) { my_error(ER_TRG_DOES_NOT_EXIST, MYF(0)); goto end; } if (!(table->triggers= new (&table->mem_root) Table_triggers_list(table))) goto end; } result= (create ? table->triggers->create_trigger(thd, tables, &stmt_query): table->triggers->drop_trigger(thd, tables, &stmt_query)); end: if (!result) { if (mysql_bin_log.is_open()) { thd->clear_error(); /* Such a statement can always go directly to binlog, no trans cache. */ thd->binlog_query(THD::MYSQL_QUERY_TYPE, stmt_query.ptr(), stmt_query.length(), FALSE, FALSE); } } VOID(pthread_mutex_unlock(&LOCK_open)); start_waiting_global_read_lock(thd); if (!result) send_ok(thd); DBUG_RETURN(result); } /* Create trigger for table. SYNOPSIS create_trigger() thd - current thread context (including trigger definition in LEX) tables - table list containing one open table for which the trigger is created. stmt_query - [OUT] after successful return, this string contains well-formed statement for creation this trigger. NOTE - Assumes that trigger name is fully qualified. - NULL-string means the following LEX_STRING instance: { str = 0; length = 0 }. - In other words, definer_user and definer_host should contain simultaneously NULL-strings (non-SUID/old trigger) or valid strings (SUID/new trigger). RETURN VALUE False - success True - error */ bool Table_triggers_list::create_trigger(THD *thd, TABLE_LIST *tables, String *stmt_query) { LEX *lex= thd->lex; TABLE *table= tables->table; char file_buff[FN_REFLEN], trigname_buff[FN_REFLEN]; LEX_STRING file, trigname_file; LEX_STRING *trg_def, *name; LEX_STRING definer_user; LEX_STRING definer_host; ulonglong *trg_sql_mode; char trg_definer_holder[USER_HOST_BUFF_SIZE]; LEX_STRING *trg_definer; Item_trigger_field *trg_field; struct st_trigname trigname; /* Trigger must be in the same schema as target table. */ if (my_strcasecmp(table_alias_charset, table->s->db.str, lex->spname->m_db.str)) { my_error(ER_TRG_IN_WRONG_SCHEMA, MYF(0)); return 1; } /* We don't allow creation of several triggers of the same type yet */ if (bodies[lex->trg_chistics.event][lex->trg_chistics.action_time]) { my_error(ER_NOT_SUPPORTED_YET, MYF(0), "multiple triggers with the same action time" " and event for one table"); return 1; } if (!lex->definer) { /* DEFINER-clause is missing. If we are in slave thread, this means that we received CREATE TRIGGER from the master, that does not support definer in triggers. So, we should mark this trigger as non-SUID. Note that this does not happen when we parse triggers' definitions during opening .TRG file. LEX::definer is ignored in that case. Otherwise, we should use CURRENT_USER() as definer. NOTE: when CREATE TRIGGER statement is allowed to be executed in PS/SP, it will be required to create the definer below in persistent MEM_ROOT of PS/SP. */ if (!thd->slave_thread) { if (!(lex->definer= create_default_definer(thd))) return 1; } } /* If the specified definer differs from the current user, we should check that the current user has SUPER privilege (in order to create trigger under another user one must have SUPER privilege). */ if (lex->definer && (strcmp(lex->definer->user.str, thd->security_ctx->priv_user) || my_strcasecmp(system_charset_info, lex->definer->host.str, thd->security_ctx->priv_host))) { if (check_global_access(thd, SUPER_ACL)) { my_error(ER_SPECIFIC_ACCESS_DENIED_ERROR, MYF(0), "SUPER"); return TRUE; } } /* Let us check if all references to fields in old/new versions of row in this trigger are ok. NOTE: We do it here more from ease of use standpoint. We still have to do some checks on each execution. E.g. we can catch privilege changes only during execution. Also in near future, when we will allow access to other tables from trigger we won't be able to catch changes in other tables... Since we don't plan to access to contents of the fields it does not matter that we choose for both OLD and NEW values the same versions of Field objects here. */ old_field= new_field= table->field; for (trg_field= (Item_trigger_field *)(lex->trg_table_fields.first); trg_field; trg_field= trg_field->next_trg_field) { /* NOTE: now we do not check privileges at CREATE TRIGGER time. This will be changed in the future. */ trg_field->setup_field(thd, table, NULL); if (!trg_field->fixed && trg_field->fix_fields(thd, (Item **)0)) return 1; } /* Here we are creating file with triggers and save all triggers in it. sql_create_definition_file() files handles renaming and backup of older versions */ file.length= build_table_filename(file_buff, FN_REFLEN-1, tables->db, tables->table_name, triggers_file_ext, 0); file.str= file_buff; trigname_file.length= build_table_filename(trigname_buff, FN_REFLEN-1, tables->db, lex->spname->m_name.str, trigname_file_ext, 0); trigname_file.str= trigname_buff; /* Use the filesystem to enforce trigger namespace constraints. */ if (!access(trigname_buff, F_OK)) { my_error(ER_TRG_ALREADY_EXISTS, MYF(0)); return 1; } trigname.trigger_table.str= tables->table_name; trigname.trigger_table.length= tables->table_name_length; if (sql_create_definition_file(NULL, &trigname_file, &trigname_file_type, (gptr)&trigname, trigname_file_parameters, 0)) return 1; /* Soon we will invalidate table object and thus Table_triggers_list object so don't care about place to which trg_def->ptr points and other invariants (e.g. we don't bother to update names_list) QQ: Hmm... probably we should not care about setting up active thread mem_root too. */ if (!(trg_def= (LEX_STRING *)alloc_root(&table->mem_root, sizeof(LEX_STRING))) || definitions_list.push_back(trg_def, &table->mem_root) || !(trg_sql_mode= (ulonglong*)alloc_root(&table->mem_root, sizeof(ulonglong))) || definition_modes_list.push_back(trg_sql_mode, &table->mem_root) || !(trg_definer= (LEX_STRING*) alloc_root(&table->mem_root, sizeof(LEX_STRING))) || definers_list.push_back(trg_definer, &table->mem_root)) goto err_with_cleanup; *trg_sql_mode= thd->variables.sql_mode; #ifndef NO_EMBEDDED_ACCESS_CHECKS if (lex->definer && !is_acl_user(lex->definer->host.str, lex->definer->user.str)) { push_warning_printf(thd, MYSQL_ERROR::WARN_LEVEL_NOTE, ER_NO_SUCH_USER, ER(ER_NO_SUCH_USER), lex->definer->user.str, lex->definer->host.str); } #endif /* NO_EMBEDDED_ACCESS_CHECKS */ if (lex->definer) { /* SUID trigger. */ definer_user= lex->definer->user; definer_host= lex->definer->host; trg_definer->str= trg_definer_holder; trg_definer->length= strxmov(trg_definer->str, definer_user.str, "@", definer_host.str, NullS) - trg_definer->str; } else { /* non-SUID trigger. */ definer_user.str= 0; definer_user.length= 0; definer_host.str= 0; definer_host.length= 0; trg_definer->str= (char*) ""; trg_definer->length= 0; } /* Create well-formed trigger definition query. Original query is not appropriated, because definer-clause can be not truncated. */ stmt_query->append(STRING_WITH_LEN("CREATE ")); if (trg_definer) { /* Append definer-clause if the trigger is SUID (a usual trigger in new MySQL versions). */ append_definer(thd, stmt_query, &definer_user, &definer_host); } stmt_query->append(thd->lex->stmt_definition_begin, (char *) thd->lex->sphead->m_body_begin - thd->lex->stmt_definition_begin + thd->lex->sphead->m_body.length); trg_def->str= stmt_query->c_ptr(); trg_def->length= stmt_query->length(); /* Create trigger definition file. */ if (!sql_create_definition_file(NULL, &file, &triggers_file_type, (gptr)this, triggers_file_parameters, 0)) return 0; err_with_cleanup: my_delete(trigname_buff, MYF(MY_WME)); return 1; } /* Deletes the .TRG file for a table SYNOPSIS rm_trigger_file() path - char buffer of size FN_REFLEN to be used for constructing path to .TRG file. db - table's database name table_name - table's name RETURN VALUE False - success True - error */ 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, 0); return my_delete(path, MYF(MY_WME)); } /* Deletes the .TRN file for a trigger SYNOPSIS rm_trigname_file() path - char buffer of size FN_REFLEN to be used for constructing path to .TRN file. db - trigger's database name table_name - trigger's name RETURN VALUE False - success True - error */ 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, 0); return my_delete(path, MYF(MY_WME)); } /* 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, 0); 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 drop_trigger() thd - current thread context (including trigger definition in LEX) tables - table list containing one open table for which trigger is dropped. stmt_query - [OUT] after successful return, this string contains well-formed statement for creation this trigger. RETURN VALUE False - success True - error */ bool Table_triggers_list::drop_trigger(THD *thd, TABLE_LIST *tables, String *stmt_query) { LEX *lex= thd->lex; LEX_STRING *name; List_iterator_fast<LEX_STRING> it_name(names_list); List_iterator<LEX_STRING> it_def(definitions_list); List_iterator<ulonglong> it_mod(definition_modes_list); List_iterator<LEX_STRING> it_definer(definers_list); char path[FN_REFLEN]; stmt_query->append(thd->query, thd->query_length); while ((name= it_name++)) { it_def++; it_mod++; it_definer++; if (my_strcasecmp(table_alias_charset, lex->spname->m_name.str, name->str) == 0) { /* Again we don't care much about other things required for clean trigger removing since table will be reopened anyway. */ it_def.remove(); it_mod.remove(); it_definer.remove(); if (definitions_list.is_empty()) { /* TODO: Probably instead of removing .TRG file we should move to archive directory but this should be done as part of parse_file.cc functionality (because we will need it elsewhere). */ if (rm_trigger_file(path, tables->db, tables->table_name)) return 1; } else { if (save_trigger_file(this, tables->db, tables->table_name)) return 1; } if (rm_trigname_file(path, tables->db, lex->spname->m_name.str)) return 1; return 0; } } my_message(ER_TRG_DOES_NOT_EXIST, ER(ER_TRG_DOES_NOT_EXIST), MYF(0)); return 1; } Table_triggers_list::~Table_triggers_list() { for (int i= 0; i < (int)TRG_EVENT_MAX; i++) for (int j= 0; j < (int)TRG_ACTION_MAX; j++) delete bodies[i][j]; if (record1_field) for (Field **fld_ptr= record1_field; *fld_ptr; fld_ptr++) delete *fld_ptr; } /* Prepare array of Field objects referencing to TABLE::record[1] instead of record[0] (they will represent OLD.* row values in ON UPDATE trigger and in ON DELETE trigger which will be called during REPLACE execution). SYNOPSIS prepare_record1_accessors() table - pointer to TABLE object for which we are creating fields. RETURN VALUE False - success True - error */ bool Table_triggers_list::prepare_record1_accessors(TABLE *table) { Field **fld, **old_fld; if (!(record1_field= (Field **)alloc_root(&table->mem_root, (table->s->fields + 1) * sizeof(Field*)))) return 1; for (fld= table->field, old_fld= record1_field; *fld; fld++, old_fld++) { /* QQ: it is supposed that it is ok to use this function for field cloning... */ if (!(*old_fld= (*fld)->new_field(&table->mem_root, table, table == (*fld)->table))) return 1; (*old_fld)->move_field_offset((my_ptrdiff_t)(table->record[1] - table->record[0])); } *old_fld= 0; return 0; } /* Adjust Table_triggers_list with new TABLE pointer. SYNOPSIS set_table() new_table - new pointer to TABLE instance */ void Table_triggers_list::set_table(TABLE *new_table) { table= new_table; for (Field **field= table->triggers->record1_field ; *field ; field++) { (*field)->table= (*field)->orig_table= new_table; (*field)->table_name= &new_table->alias; } } /* Check whenever .TRG file for table exist and load all triggers it contains. SYNOPSIS check_n_load() thd - current thread context db - table's database name table_name - table's name table - pointer to table object names_only - stop after loading trigger names RETURN VALUE False - success True - error */ bool Table_triggers_list::check_n_load(THD *thd, const char *db, const char *table_name, TABLE *table, bool names_only) { char path_buff[FN_REFLEN]; LEX_STRING path; File_parser *parser; LEX_STRING save_db; DBUG_ENTER("Table_triggers_list::check_n_load"); path.length= build_table_filename(path_buff, FN_REFLEN-1, db, table_name, triggers_file_ext, 0); path.str= path_buff; // QQ: should we analyze errno somehow ? if (access(path_buff, F_OK)) DBUG_RETURN(0); /* File exists so we got to load triggers. FIXME: A lot of things to do here e.g. how about other funcs and being more paranoical ? */ if ((parser= sql_parse_prepare(&path, &table->mem_root, 1))) { if (is_equal(&triggers_file_type, parser->type())) { Table_triggers_list *triggers= new (&table->mem_root) Table_triggers_list(table); Handle_old_incorrect_sql_modes_hook sql_modes_hook(path.str); if (!triggers) DBUG_RETURN(1); /* We don't have the following attributes in old versions of .TRG file, so we should initialize the list for safety: - sql_modes; - definers; */ triggers->definition_modes_list.empty(); triggers->definers_list.empty(); if (parser->parse((gptr)triggers, &table->mem_root, triggers_file_parameters, TRG_NUM_REQUIRED_PARAMETERS, &sql_modes_hook)) DBUG_RETURN(1); List_iterator_fast<LEX_STRING> it(triggers->definitions_list); LEX_STRING *trg_create_str, *trg_name_str; ulonglong *trg_sql_mode; if (triggers->definition_modes_list.is_empty() && !triggers->definitions_list.is_empty()) { /* It is old file format => we should fill list of sql_modes. We use one mode (current) for all triggers, because we have not information about mode in old format. */ if (!(trg_sql_mode= (ulonglong*)alloc_root(&table->mem_root, sizeof(ulonglong)))) { DBUG_RETURN(1); // EOM } *trg_sql_mode= global_system_variables.sql_mode; while (it++) { if (triggers->definition_modes_list.push_back(trg_sql_mode, &table->mem_root)) { DBUG_RETURN(1); // EOM } } it.rewind(); } if (triggers->definers_list.is_empty() && !triggers->definitions_list.is_empty()) { /* It is old file format => we should fill list of definers. If there is no definer information, we should not switch context to definer when checking privileges. I.e. privileges for such triggers are checked for "invoker" rather than for "definer". */ LEX_STRING *trg_definer; if (! (trg_definer= (LEX_STRING*)alloc_root(&table->mem_root, sizeof(LEX_STRING)))) DBUG_RETURN(1); // EOM trg_definer->str= (char*) ""; trg_definer->length= 0; while (it++) { if (triggers->definers_list.push_back(trg_definer, &table->mem_root)) { DBUG_RETURN(1); // EOM } } it.rewind(); } DBUG_ASSERT(triggers->definition_modes_list.elements == triggers->definitions_list.elements); DBUG_ASSERT(triggers->definers_list.elements == triggers->definitions_list.elements); table->triggers= triggers; /* Construct key that will represent triggers for this table in the set of routines used by statement. */ triggers->sroutines_key.length= 1+strlen(db)+1+strlen(table_name)+1; if (!(triggers->sroutines_key.str= alloc_root(&table->mem_root, triggers->sroutines_key.length))) DBUG_RETURN(1); triggers->sroutines_key.str[0]= TYPE_ENUM_TRIGGER; strxmov(triggers->sroutines_key.str+1, db, ".", table_name, NullS); /* TODO: This could be avoided if there is no triggers for UPDATE and DELETE. */ if (!names_only && triggers->prepare_record1_accessors(table)) DBUG_RETURN(1); 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; save_db.str= thd->db; save_db.length= thd->db_length; thd->reset_db((char*) db, strlen(db)); while ((trg_create_str= it++)) { trg_sql_mode= itm++; LEX_STRING *trg_definer= it_definer++; thd->variables.sql_mode= (ulong)*trg_sql_mode; lex_start(thd, (uchar*)trg_create_str->str, trg_create_str->length); thd->spcont= 0; if (MYSQLparse((void *)thd) || thd->is_fatal_error) { /* Free lex associated resources. QQ: Do we really need all this stuff here ? */ delete lex.sphead; goto err_with_lex_cleanup; } lex.sphead->set_info(0, 0, &lex.sp_chistics, *trg_sql_mode); triggers->bodies[lex.trg_chistics.event] [lex.trg_chistics.action_time]= lex.sphead; if (!trg_definer->length) { /* This trigger was created/imported from the previous version of MySQL, which does not support triggers definers. We should emit warning here. */ push_warning_printf(thd, MYSQL_ERROR::WARN_LEVEL_WARN, ER_TRG_NO_DEFINER, ER(ER_TRG_NO_DEFINER), (const char*) db, (const char*) lex.sphead->m_name.str); /* Set definer to the '' to correct displaying in the information schema. */ lex.sphead->set_definer((char*) "", 0); /* Triggers without definer information are executed under the authorization of the invoker. */ lex.sphead->m_chistics->suid= SP_IS_NOT_SUID; } else lex.sphead->set_definer(trg_definer->str, trg_definer->length); if (triggers->names_list.push_back(&lex.sphead->m_name, &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); continue; } /* Gather all Item_trigger_field objects representing access to fields in old/new versions of row in trigger into lists containing all such objects for the triggers with same action and timing. */ triggers->trigger_fields[lex.trg_chistics.event] [lex.trg_chistics.action_time]= (Item_trigger_field *)(lex.trg_table_fields.first); /* Also let us bind these objects to Field objects in table being opened. We ignore errors here, because if even something is wrong we still will be willing to open table to perform some operations (e.g. SELECT)... Anyway some things can be checked only during trigger execution. */ for (Item_trigger_field *trg_field= (Item_trigger_field *)(lex.trg_table_fields.first); trg_field; trg_field= trg_field->next_trg_field) { trg_field->setup_field(thd, table, &triggers->subject_table_grants[lex.trg_chistics.event] [lex.trg_chistics.action_time]); } lex_end(&lex); } thd->reset_db(save_db.str, save_db.length); thd->lex= old_lex; thd->spcont= save_spcont; thd->variables.sql_mode= save_sql_mode; DBUG_RETURN(0); err_with_lex_cleanup: // QQ: anything else ? lex_end(&lex); thd->lex= old_lex; thd->spcont= save_spcont; thd->variables.sql_mode= save_sql_mode; thd->reset_db(save_db.str, save_db.length); DBUG_RETURN(1); } /* We don't care about this error message much because .TRG files will be merged into .FRM anyway. */ my_error(ER_WRONG_OBJECT, MYF(0), table_name, triggers_file_ext+1, "TRIGGER"); DBUG_RETURN(1); } DBUG_RETURN(1); } /* Obtains and returns trigger metadata SYNOPSIS get_trigger_info() thd - current thread context event - trigger event type time_type - trigger action time name - returns name of trigger stmt - returns statement of trigger sql_mode - returns sql_mode of trigger definer_user - returns definer/creator of trigger. The caller is responsible to allocate enough space for storing definer information. RETURN VALUE False - success True - error */ bool Table_triggers_list::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) { sp_head *body; DBUG_ENTER("get_trigger_info"); if ((body= bodies[event][time_type])) { *trigger_name= body->m_name; *trigger_stmt= body->m_body; *sql_mode= body->m_sql_mode; if (body->m_chistics->suid == SP_IS_NOT_SUID) { definer->str[0]= 0; definer->length= 0; } else { definer->length= strxmov(definer->str, body->m_definer_user.str, "@", body->m_definer_host.str, NullS) - definer->str; } DBUG_RETURN(0); } DBUG_RETURN(1); } /* Find trigger's table from trigger identifier and add it to the statement table list. SYNOPSIS mysql_table_for_trigger() thd - current thread context trig - identifier for trigger RETURN VALUE 0 - error # - pointer to TABLE_LIST object for the table */ static TABLE_LIST *add_table_for_trigger(THD *thd, sp_name *trig) { LEX *lex= thd->lex; char path_buff[FN_REFLEN]; LEX_STRING path; File_parser *parser; struct st_trigname trigname; Handle_old_incorrect_trigger_table_hook trigger_table_hook( path_buff, &trigname.trigger_table); DBUG_ENTER("add_table_for_trigger"); path.length= build_table_filename(path_buff, FN_REFLEN-1, trig->m_db.str, trig->m_name.str, trigname_file_ext, 0); path.str= path_buff; if (access(path_buff, F_OK)) { my_error(ER_TRG_DOES_NOT_EXIST, MYF(0)); DBUG_RETURN(0); } if (!(parser= sql_parse_prepare(&path, thd->mem_root, 1))) DBUG_RETURN(0); if (!is_equal(&trigname_file_type, parser->type())) { my_error(ER_WRONG_OBJECT, MYF(0), trig->m_name.str, trigname_file_ext+1, "TRIGGERNAME"); DBUG_RETURN(0); } if (parser->parse((gptr)&trigname, thd->mem_root, trigname_file_parameters, 1, &trigger_table_hook)) DBUG_RETURN(0); /* We need to reset statement table list to be PS/SP friendly. */ 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_IGNORE)); } /* Drop all triggers for table. SYNOPSIS drop_all_triggers() thd - current thread context db - schema for table name - name for table NOTE The calling thread should hold the LOCK_open mutex; RETURN VALUE False - success True - error */ bool Table_triggers_list::drop_all_triggers(THD *thd, char *db, char *name) { TABLE table; char path[FN_REFLEN]; bool result= 0; DBUG_ENTER("drop_all_triggers"); 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, name, &table, 1)) { result= 1; goto end; } if (table.triggers) { LEX_STRING *trigger; List_iterator_fast<LEX_STRING> it_name(table.triggers->names_list); while ((trigger= it_name++)) { if (rm_trigname_file(path, db, trigger->str)) { /* Instead of immediately bailing out with error if we were unable to remove .TRN file we will try to drop other files. */ result= 1; continue; } } if (rm_trigger_file(path, db, name)) { result= 1; goto end; } } end: if (table.triggers) delete table.triggers; free_root(&table.mem_root, MYF(0)); DBUG_RETURN(result); } /* 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); buff.append(STRING_WITH_LEN(" ")); 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, 0); 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. Also this method assumes that subject table is not renamed to itself. 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); DBUG_ASSERT(my_strcasecmp(table_alias_charset, db, new_db) || my_strcasecmp(table_alias_charset, old_table, new_table)); if (Table_triggers_list::check_n_load(thd, db, old_table, &table, TRUE)) { result= 1; goto end; } if (table.triggers) { LEX_STRING old_table_name= { (char *) old_table, strlen(old_table) }; LEX_STRING new_table_name= { (char *) 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, bool old_row_is_record1) { bool err_status= FALSE; sp_head *sp_trigger= bodies[event][time_type]; if (sp_trigger) { Sub_statement_state statement_state; if (old_row_is_record1) { old_field= record1_field; new_field= table->field; } else { new_field= record1_field; old_field= table->field; } #ifndef NO_EMBEDDED_ACCESS_CHECKS Security_context *save_ctx; if (sp_change_security_context(thd, sp_trigger, &save_ctx)) return TRUE; /* Fetch information about table-level privileges to GRANT_INFO structure for subject table. Check of privileges that will use it and information about column-level privileges will happen in Item_trigger_field::fix_fields(). */ fill_effective_table_privileges(thd, &subject_table_grants[event][time_type], table->s->db.str, table->s->table_name.str); /* Check that the definer has TRIGGER privilege on the subject table. */ if (!(subject_table_grants[event][time_type].privilege & TRIGGER_ACL)) { char priv_desc[128]; get_privilege_desc(priv_desc, sizeof(priv_desc), TRIGGER_ACL); my_error(ER_TABLEACCESS_DENIED_ERROR, MYF(0), priv_desc, thd->security_ctx->priv_user, thd->security_ctx->host_or_ip, table->s->table_name.str); sp_restore_security_context(thd, save_ctx); return TRUE; } #endif // NO_EMBEDDED_ACCESS_CHECKS thd->reset_sub_statement_state(&statement_state, SUB_STMT_TRIGGER); err_status= sp_trigger->execute_trigger (thd, table->s->db.str, table->s->table_name.str, &subject_table_grants[event][time_type]); thd->restore_sub_statement_state(&statement_state); #ifndef NO_EMBEDDED_ACCESS_CHECKS sp_restore_security_context(thd, save_ctx); #endif // NO_EMBEDDED_ACCESS_CHECKS } return err_status; } /* Mark fields of subject table which we read/set in its triggers as such. SYNOPSIS mark_fields_used() thd Current thread context event Type of event triggers for which we are going to inspect DESCRIPTION This method marks fields of subject table which are read/set in its triggers as such (by properly updating TABLE::read_set/write_set) and thus informs handler that values for these fields should be retrieved/stored during execution of statement. */ void Table_triggers_list::mark_fields_used(trg_event_type event) { int action_time; Item_trigger_field *trg_field; for (action_time= 0; action_time < (int)TRG_ACTION_MAX; action_time++) { for (trg_field= trigger_fields[event][action_time]; trg_field; trg_field= trg_field->next_trg_field) { /* We cannot mark fields which does not present in table. */ if (trg_field->field_idx != (uint)-1) { bitmap_set_bit(table->read_set, trg_field->field_idx); if (trg_field->get_settable_routine_parameter()) bitmap_set_bit(table->write_set, trg_field->field_idx); } } } table->file->column_bitmaps_signal(); } /* Trigger BUG#14090 compatibility hook SYNOPSIS Handle_old_incorrect_sql_modes_hook::process_unknown_string() unknown_key [in/out] reference on the line with unknown parameter and the parsing point base [in] base address for parameter writing (structure like TABLE) mem_root [in] MEM_ROOT for parameters allocation end [in] the end of the configuration NOTE: this hook process back compatibility for incorrectly written sql_modes parameter (see BUG#14090). RETURN FALSE OK TRUE Error */ #define INVALID_SQL_MODES_LENGTH 13 bool Handle_old_incorrect_sql_modes_hook::process_unknown_string(char *&unknown_key, gptr base, MEM_ROOT *mem_root, char *end) { DBUG_ENTER("Handle_old_incorrect_sql_modes_hook::process_unknown_string"); DBUG_PRINT("info", ("unknown key:%60s", unknown_key)); if (unknown_key + INVALID_SQL_MODES_LENGTH + 1 < end && unknown_key[INVALID_SQL_MODES_LENGTH] == '=' && !memcmp(unknown_key, STRING_WITH_LEN("sql_modes"))) { char *ptr= unknown_key + INVALID_SQL_MODES_LENGTH + 1; DBUG_PRINT("info", ("sql_modes affected by BUG#14090 detected")); push_warning_printf(current_thd, MYSQL_ERROR::WARN_LEVEL_NOTE, ER_OLD_FILE_FORMAT, ER(ER_OLD_FILE_FORMAT), (char *)path, "TRIGGER"); if (get_file_options_ulllist(ptr, end, unknown_key, base, &sql_modes_parameters, mem_root)) { DBUG_RETURN(TRUE); } /* Set parsing pointer to the last symbol of string (\n) 1) to avoid problem with \0 in the junk after sql_modes 2) to speed up skipping this line by parser. */ unknown_key= ptr-1; } DBUG_RETURN(FALSE); } /* Trigger BUG#15921 compatibility hook. For details see Handle_old_incorrect_sql_modes_hook::process_unknown_string(). */ #define INVALID_TRIGGER_TABLE_LENGTH 15 bool Handle_old_incorrect_trigger_table_hook:: process_unknown_string(char *&unknown_key, gptr base, MEM_ROOT *mem_root, char *end) { DBUG_ENTER("Handle_old_incorrect_trigger_table_hook::process_unknown_string"); DBUG_PRINT("info", ("unknown key:%60s", unknown_key)); if (unknown_key + INVALID_TRIGGER_TABLE_LENGTH + 1 < end && unknown_key[INVALID_TRIGGER_TABLE_LENGTH] == '=' && !memcmp(unknown_key, STRING_WITH_LEN("trigger_table"))) { char *ptr= unknown_key + INVALID_TRIGGER_TABLE_LENGTH + 1; DBUG_PRINT("info", ("trigger_table affected by BUG#15921 detected")); push_warning_printf(current_thd, MYSQL_ERROR::WARN_LEVEL_NOTE, ER_OLD_FILE_FORMAT, ER(ER_OLD_FILE_FORMAT), (char *)path, "TRIGGER"); if (!(ptr= parse_escaped_string(ptr, end, mem_root, trigger_table_value))) { my_error(ER_FPARSER_ERROR_IN_PARAMETER, MYF(0), "trigger_table", unknown_key); DBUG_RETURN(TRUE); } /* Set parsing pointer to the last symbol of string (\n). */ unknown_key= ptr-1; } DBUG_RETURN(FALSE); }