/* Copyright (c) 2000, 2014, Oracle and/or its affiliates. Copyright (c) 2009, 2016, 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 Street, Fifth Floor, Boston, MA 02110-1301, USA */ /* create and drop of databases */ #include /* NO_EMBEDDED_ACCESS_CHECKS */ #include "sql_priv.h" #include "unireg.h" #include "sql_db.h" #include "sql_cache.h" // query_cache_* #include "lock.h" // lock_schema_name #include "sql_table.h" // build_table_filename, // filename_to_tablename #include "sql_rename.h" // mysql_rename_tables #include "sql_acl.h" // SELECT_ACL, DB_ACLS, // acl_get, check_grant_db #include "log_event.h" // Query_log_event #include "sql_base.h" // lock_table_names, tdc_remove_table #include "sql_handler.h" // mysql_ha_rm_tables #include "sql_class.h" #include #include "sp_head.h" #include "sp.h" #include "events.h" #include "sql_handler.h" #include "sql_statistics.h" #include #include #include "log.h" #ifdef __WIN__ #include #endif #include "debug_sync.h" #define MAX_DROP_TABLE_Q_LEN 1024 const char *del_exts[]= {".BAK", ".opt", NullS}; static TYPELIB deletable_extentions= {array_elements(del_exts)-1,"del_exts", del_exts, NULL}; static bool find_db_tables_and_rm_known_files(THD *, MY_DIR *, char *, const char *, TABLE_LIST **); long mysql_rm_arc_files(THD *thd, MY_DIR *dirp, const char *org_path); static my_bool rm_dir_w_symlink(const char *org_path, my_bool send_error); static void mysql_change_db_impl(THD *thd, LEX_STRING *new_db_name, ulong new_db_access, CHARSET_INFO *new_db_charset); static bool mysql_rm_db_internal(THD *thd, char *db, bool if_exists, bool silent); /* Database options hash */ static HASH dboptions; static my_bool dboptions_init= 0; static mysql_rwlock_t LOCK_dboptions; /* Structure for database options */ typedef struct my_dbopt_st { char *name; /* Database name */ uint name_length; /* Database length name */ CHARSET_INFO *charset; /* Database default character set */ } my_dbopt_t; /** Return TRUE if db1_name is equal to db2_name, FALSE otherwise. The function allows to compare database names according to the MariaDB rules. The database names db1 and db2 are equal if: - db1 is NULL and db2 is NULL; or - db1 is not-NULL, db2 is not-NULL, db1 is equal to db2 in table_alias_charset This is the same rules as we use for filenames. */ static inline bool cmp_db_names(const char *db1_name, const char *db2_name) { return ((!db1_name && !db2_name) || (db1_name && db2_name && my_strcasecmp(table_alias_charset, db1_name, db2_name) == 0)); } /* Function we use in the creation of our hash to get key. */ extern "C" uchar* dboptions_get_key(my_dbopt_t *opt, size_t *length, my_bool not_used); uchar* dboptions_get_key(my_dbopt_t *opt, size_t *length, my_bool not_used __attribute__((unused))) { *length= opt->name_length; return (uchar*) opt->name; } /* Helper function to write a query to binlog used by mysql_rm_db() */ static inline int write_to_binlog(THD *thd, char *query, uint q_len, char *db, uint db_len) { Query_log_event qinfo(thd, query, q_len, FALSE, TRUE, FALSE, 0); qinfo.db= db; qinfo.db_len= db_len; return mysql_bin_log.write(&qinfo); } /* Function to free dboptions hash element */ extern "C" void free_dbopt(void *dbopt); void free_dbopt(void *dbopt) { my_free(dbopt); } #ifdef HAVE_PSI_INTERFACE static PSI_rwlock_key key_rwlock_LOCK_dboptions; static PSI_rwlock_info all_database_names_rwlocks[]= { { &key_rwlock_LOCK_dboptions, "LOCK_dboptions", PSI_FLAG_GLOBAL} }; static void init_database_names_psi_keys(void) { const char* category= "sql"; int count; if (PSI_server == NULL) return; count= array_elements(all_database_names_rwlocks); PSI_server->register_rwlock(category, all_database_names_rwlocks, count); } #endif /** Initialize database option cache. @note Must be called before any other database function is called. @retval 0 ok @retval 1 Fatal error */ bool my_dboptions_cache_init(void) { #ifdef HAVE_PSI_INTERFACE init_database_names_psi_keys(); #endif bool error= 0; mysql_rwlock_init(key_rwlock_LOCK_dboptions, &LOCK_dboptions); if (!dboptions_init) { dboptions_init= 1; error= my_hash_init(&dboptions, table_alias_charset, 32, 0, 0, (my_hash_get_key) dboptions_get_key, free_dbopt,0); } return error; } /** Free database option hash and locked databases hash. */ void my_dboptions_cache_free(void) { if (dboptions_init) { dboptions_init= 0; my_hash_free(&dboptions); mysql_rwlock_destroy(&LOCK_dboptions); } } /** Cleanup cached options. */ void my_dbopt_cleanup(void) { mysql_rwlock_wrlock(&LOCK_dboptions); my_hash_free(&dboptions); my_hash_init(&dboptions, table_alias_charset, 32, 0, 0, (my_hash_get_key) dboptions_get_key, free_dbopt,0); mysql_rwlock_unlock(&LOCK_dboptions); } /* Find database options in the hash. DESCRIPTION Search a database options in the hash, usings its path. Fills "create" on success. RETURN VALUES 0 on success. 1 on error. */ static my_bool get_dbopt(const char *dbname, Schema_specification_st *create) { my_dbopt_t *opt; uint length; my_bool error= 1; length= (uint) strlen(dbname); mysql_rwlock_rdlock(&LOCK_dboptions); if ((opt= (my_dbopt_t*) my_hash_search(&dboptions, (uchar*) dbname, length))) { create->default_table_charset= opt->charset; error= 0; } mysql_rwlock_unlock(&LOCK_dboptions); return error; } /* Writes database options into the hash. DESCRIPTION Inserts database options into the hash, or updates options if they are already in the hash. RETURN VALUES 0 on success. 1 on error. */ static my_bool put_dbopt(const char *dbname, Schema_specification_st *create) { my_dbopt_t *opt; uint length; my_bool error= 0; DBUG_ENTER("put_dbopt"); length= (uint) strlen(dbname); mysql_rwlock_wrlock(&LOCK_dboptions); if (!(opt= (my_dbopt_t*) my_hash_search(&dboptions, (uchar*) dbname, length))) { /* Options are not in the hash, insert them */ char *tmp_name; if (!my_multi_malloc(MYF(MY_WME | MY_ZEROFILL), &opt, (uint) sizeof(*opt), &tmp_name, (uint) length+1, NullS)) { error= 1; goto end; } opt->name= tmp_name; strmov(opt->name, dbname); opt->name_length= length; if ((error= my_hash_insert(&dboptions, (uchar*) opt))) { my_free(opt); goto end; } } /* Update / write options in hash */ opt->charset= create->default_table_charset; end: mysql_rwlock_unlock(&LOCK_dboptions); DBUG_RETURN(error); } /* Deletes database options from the hash. */ static void del_dbopt(const char *path) { my_dbopt_t *opt; mysql_rwlock_wrlock(&LOCK_dboptions); if ((opt= (my_dbopt_t *)my_hash_search(&dboptions, (const uchar*) path, strlen(path)))) my_hash_delete(&dboptions, (uchar*) opt); mysql_rwlock_unlock(&LOCK_dboptions); } /* Create database options file: DESCRIPTION Currently database default charset is only stored there. RETURN VALUES 0 ok 1 Could not create file or write to it. Error sent through my_error() */ static bool write_db_opt(THD *thd, const char *path, Schema_specification_st *create) { register File file; char buf[256]; // Should be enough for one option bool error=1; if (!create->default_table_charset) create->default_table_charset= thd->variables.collation_server; if (put_dbopt(path, create)) return 1; if ((file= mysql_file_create(key_file_dbopt, path, CREATE_MODE, O_RDWR | O_TRUNC, MYF(MY_WME))) >= 0) { ulong length; length= (ulong) (strxnmov(buf, sizeof(buf)-1, "default-character-set=", create->default_table_charset->csname, "\ndefault-collation=", create->default_table_charset->name, "\n", NullS) - buf); /* Error is written by mysql_file_write */ if (!mysql_file_write(file, (uchar*) buf, length, MYF(MY_NABP+MY_WME))) error=0; mysql_file_close(file, MYF(0)); } return error; } /* Load database options file load_db_opt() path Path for option file create Where to store the read options DESCRIPTION RETURN VALUES 0 File found 1 No database file or could not open it */ bool load_db_opt(THD *thd, const char *path, Schema_specification_st *create) { File file; char buf[256]; DBUG_ENTER("load_db_opt"); bool error=1; uint nbytes; bzero((char*) create,sizeof(*create)); create->default_table_charset= thd->variables.collation_server; /* Check if options for this database are already in the hash */ if (!get_dbopt(path, create)) DBUG_RETURN(0); /* Otherwise, load options from the .opt file */ if ((file= mysql_file_open(key_file_dbopt, path, O_RDONLY | O_SHARE, MYF(0))) < 0) goto err1; IO_CACHE cache; if (init_io_cache(&cache, file, IO_SIZE, READ_CACHE, 0, 0, MYF(0))) goto err2; while ((int) (nbytes= my_b_gets(&cache, (char*) buf, sizeof(buf))) > 0) { char *pos= buf+nbytes-1; /* Remove end space and control characters */ while (pos > buf && !my_isgraph(&my_charset_latin1, pos[-1])) pos--; *pos=0; if ((pos= strchr(buf, '='))) { if (!strncmp(buf,"default-character-set", (pos-buf))) { /* Try character set name, and if it fails try collation name, probably it's an old 4.1.0 db.opt file, which didn't have separate default-character-set and default-collation commands. */ if (!(create->default_table_charset= get_charset_by_csname(pos+1, MY_CS_PRIMARY, MYF(0))) && !(create->default_table_charset= get_charset_by_name(pos+1, MYF(0)))) { sql_print_error("Error while loading database options: '%s':",path); sql_print_error(ER_THD(thd, ER_UNKNOWN_CHARACTER_SET),pos+1); create->default_table_charset= default_charset_info; } } else if (!strncmp(buf,"default-collation", (pos-buf))) { if (!(create->default_table_charset= get_charset_by_name(pos+1, MYF(0)))) { sql_print_error("Error while loading database options: '%s':",path); sql_print_error(ER_THD(thd, ER_UNKNOWN_COLLATION),pos+1); create->default_table_charset= default_charset_info; } } } } /* Put the loaded value into the hash. Note that another thread could've added the same entry to the hash after we called get_dbopt(), but it's not an error, as put_dbopt() takes this possibility into account. */ error= put_dbopt(path, create); end_io_cache(&cache); err2: mysql_file_close(file, MYF(0)); err1: DBUG_RETURN(error); } /* Retrieve database options by name. Load database options file or fetch from cache. SYNOPSIS load_db_opt_by_name() db_name Database name db_create_info Where to store the database options DESCRIPTION load_db_opt_by_name() is a shortcut for load_db_opt(). NOTE Although load_db_opt_by_name() (and load_db_opt()) returns status of the operation, it is useless usually and should be ignored. The problem is that there are 1) system databases ("mysql") and 2) virtual databases ("information_schema"), which do not contain options file. So, load_db_opt[_by_name]() returns FALSE for these databases, but this is not an error. load_db_opt[_by_name]() clears db_create_info structure in any case, so even on failure it contains valid data. So, common use case is just call load_db_opt[_by_name]() without checking return value and use db_create_info right after that. RETURN VALUES (read NOTE!) FALSE Success TRUE Failed to retrieve options */ bool load_db_opt_by_name(THD *thd, const char *db_name, Schema_specification_st *db_create_info) { char db_opt_path[FN_REFLEN + 1]; /* Pass an empty file name, and the database options file name as extension to avoid table name to file name encoding. */ (void) build_table_filename(db_opt_path, sizeof(db_opt_path) - 1, db_name, "", MY_DB_OPT_FILE, 0); return load_db_opt(thd, db_opt_path, db_create_info); } /** Return default database collation. @param thd Thread context. @param db_name Database name. @return CHARSET_INFO object. The operation always return valid character set, even if the database does not exist. */ CHARSET_INFO *get_default_db_collation(THD *thd, const char *db_name) { Schema_specification_st db_info; if (thd->db != NULL && strcmp(db_name, thd->db) == 0) return thd->db_charset; load_db_opt_by_name(thd, db_name, &db_info); /* NOTE: even if load_db_opt_by_name() fails, db_info.default_table_charset contains valid character set (collation_server). We should not fail if load_db_opt_by_name() fails, because it is valid case. If a database has been created just by "mkdir", it does not contain db.opt file, but it is valid database. */ return db_info.default_table_charset; } /* Create a database SYNOPSIS mysql_create_db_iternal() thd Thread handler db Name of database to create Function assumes that this is already validated. options DDL options, e.g. IF NOT EXISTS create_info Database create options (like character set) silent Used by replication when internally creating a database. In this case the entry should not be logged. SIDE-EFFECTS 1. Report back to client that command succeeded (my_ok) 2. Report errors to client 3. Log event to binary log (The 'silent' flags turns off 1 and 3.) RETURN VALUES FALSE ok TRUE Error */ static int mysql_create_db_internal(THD *thd, char *db, const DDL_options_st &options, Schema_specification_st *create_info, bool silent) { char path[FN_REFLEN+16]; MY_STAT stat_info; uint path_len; DBUG_ENTER("mysql_create_db"); /* do not create 'information_schema' db */ if (is_infoschema_db(db)) { my_error(ER_DB_CREATE_EXISTS, MYF(0), db); DBUG_RETURN(-1); } char db_tmp[SAFE_NAME_LEN], *dbnorm; if (lower_case_table_names) { strmake_buf(db_tmp, db); my_casedn_str(system_charset_info, db_tmp); dbnorm= db_tmp; } else dbnorm= db; if (lock_schema_name(thd, dbnorm)) DBUG_RETURN(-1); /* Check directory */ path_len= build_table_filename(path, sizeof(path) - 1, db, "", "", 0); path[path_len-1]= 0; // Remove last '/' from path long affected_rows= 1; if (!mysql_file_stat(key_file_misc, path, &stat_info, MYF(0))) { // The database directory does not exist, or my_file_stat() failed if (my_errno != ENOENT) { my_error(EE_STAT, MYF(0), path, my_errno); DBUG_RETURN(1); } } else if (options.or_replace()) { if (mysql_rm_db_internal(thd, db, 0, true)) // Removing the old database DBUG_RETURN(1); /* Reset the diagnostics m_status. It might be set ot DA_OK in mysql_rm_db. */ thd->get_stmt_da()->reset_diagnostics_area(); affected_rows= 2; } else if (options.if_not_exists()) { push_warning_printf(thd, Sql_condition::WARN_LEVEL_NOTE, ER_DB_CREATE_EXISTS, ER_THD(thd, ER_DB_CREATE_EXISTS), db); affected_rows= 0; goto not_silent; } else { my_error(ER_DB_CREATE_EXISTS, MYF(0), db); DBUG_RETURN(-1); } if (my_mkdir(path, 0777, MYF(0)) < 0) { my_error(ER_CANT_CREATE_DB, MYF(0), db, my_errno); DBUG_RETURN(-1); } path[path_len-1]= FN_LIBCHAR; strmake(path+path_len, MY_DB_OPT_FILE, sizeof(path)-path_len-1); if (write_db_opt(thd, path, create_info)) { /* Could not create options file. Restore things to beginning. */ path[path_len]= 0; if (rmdir(path) >= 0) DBUG_RETURN(-1); /* We come here when we managed to create the database, but not the option file. In this case it's best to just continue as if nothing has happened. (This is a very unlikely senario) */ thd->clear_error(); } not_silent: if (!silent) { char *query; uint query_length; query= thd->query(); query_length= thd->query_length(); DBUG_ASSERT(query); if (mysql_bin_log.is_open()) { int errcode= query_error_code(thd, TRUE); Query_log_event qinfo(thd, query, query_length, FALSE, TRUE, /* suppress_use */ TRUE, errcode); /* Write should use the database being created as the "current database" and not the threads current database, which is the default. If we do not change the "current database" to the database being created, the CREATE statement will not be replicated when using --binlog-do-db to select databases to be replicated. An example (--binlog-do-db=sisyfos): CREATE DATABASE bob; # Not replicated USE bob; # 'bob' is the current database CREATE DATABASE sisyfos; # Not replicated since 'bob' is # current database. USE sisyfos; # Will give error on slave since # database does not exist. */ qinfo.db = db; qinfo.db_len = strlen(db); /* These DDL methods and logging are protected with the exclusive metadata lock on the schema */ if (mysql_bin_log.write(&qinfo)) DBUG_RETURN(-1); } my_ok(thd, affected_rows); } DBUG_RETURN(0); } /* db-name is already validated when we come here */ static bool mysql_alter_db_internal(THD *thd, const char *db, Schema_specification_st *create_info) { char path[FN_REFLEN+16]; long result=1; int error= 0; DBUG_ENTER("mysql_alter_db"); if (lock_schema_name(thd, db)) DBUG_RETURN(TRUE); /* Recreate db options file: /dbpath/.db.opt We pass MY_DB_OPT_FILE as "extension" to avoid "table name to file name" encoding. */ build_table_filename(path, sizeof(path) - 1, db, "", MY_DB_OPT_FILE, 0); if ((error=write_db_opt(thd, path, create_info))) goto exit; /* Change options if current database is being altered. */ if (thd->db && !strcmp(thd->db,db)) { thd->db_charset= create_info->default_table_charset ? create_info->default_table_charset : thd->variables.collation_server; thd->variables.collation_database= thd->db_charset; } if (mysql_bin_log.is_open()) { int errcode= query_error_code(thd, TRUE); Query_log_event qinfo(thd, thd->query(), thd->query_length(), FALSE, TRUE, /* suppress_use */ TRUE, errcode); /* Write should use the database being created as the "current database" and not the threads current database, which is the default. */ qinfo.db = db; qinfo.db_len = strlen(db); /* These DDL methods and logging are protected with the exclusive metadata lock on the schema. */ if ((error= mysql_bin_log.write(&qinfo))) goto exit; } my_ok(thd, result); exit: DBUG_RETURN(error); } int mysql_create_db(THD *thd, char *db, const DDL_options_st &options, const Schema_specification_st *create_info) { /* As mysql_create_db_internal() may modify Db_create_info structure passed to it, we need to use a copy to make execution prepared statement- safe. */ Schema_specification_st tmp(*create_info); return mysql_create_db_internal(thd, db, options, &tmp, false); } bool mysql_alter_db(THD *thd, const char *db, const Schema_specification_st *create_info) { /* As mysql_alter_db_internal() may modify Db_create_info structure passed to it, we need to use a copy to make execution prepared statement- safe. */ Schema_specification_st tmp(*create_info); return mysql_alter_db_internal(thd, db, &tmp); } /** Drop all tables, routines and events in a database and the database itself. @param thd Thread handle @param db Database name in the case given by user It's already validated and set to lower case (if needed) when we come here @param if_exists Don't give error if database doesn't exists @param silent Don't write the statement to the binary log and don't send ok packet to the client @retval false OK (Database dropped) @retval true Error */ static bool mysql_rm_db_internal(THD *thd,char *db, bool if_exists, bool silent) { ulong deleted_tables= 0; bool error= true; char path[FN_REFLEN + 16]; MY_DIR *dirp; uint length; TABLE_LIST *tables= NULL; TABLE_LIST *table; Drop_table_error_handler err_handler; DBUG_ENTER("mysql_rm_db"); char db_tmp[SAFE_NAME_LEN], *dbnorm; if (lower_case_table_names) { strmake_buf(db_tmp, db); my_casedn_str(system_charset_info, db_tmp); dbnorm= db_tmp; } else dbnorm= db; if (lock_schema_name(thd, dbnorm)) DBUG_RETURN(true); length= build_table_filename(path, sizeof(path) - 1, db, "", "", 0); strmov(path+length, MY_DB_OPT_FILE); // Append db option file name del_dbopt(path); // Remove dboption hash entry path[length]= '\0'; // Remove file name /* See if the directory exists */ if (!(dirp= my_dir(path,MYF(MY_DONT_SORT)))) { if (!if_exists) { my_error(ER_DB_DROP_EXISTS, MYF(0), db); DBUG_RETURN(true); } else { push_warning_printf(thd, Sql_condition::WARN_LEVEL_NOTE, ER_DB_DROP_EXISTS, ER_THD(thd, ER_DB_DROP_EXISTS), db); error= false; goto update_binlog; } } if (find_db_tables_and_rm_known_files(thd, dirp, dbnorm, path, &tables)) goto exit; /* Disable drop of enabled log tables, must be done before name locking. This check is only needed if we are dropping the "mysql" database. */ if ((my_strcasecmp(system_charset_info, MYSQL_SCHEMA_NAME.str, db) == 0)) { for (table= tables; table; table= table->next_local) if (check_if_log_table(table, TRUE, "DROP")) goto exit; } /* Lock all tables and stored routines about to be dropped. */ if (lock_table_names(thd, tables, NULL, thd->variables.lock_wait_timeout, 0) || lock_db_routines(thd, dbnorm)) goto exit; if (!in_bootstrap) { for (table= tables; table; table= table->next_local) { LEX_STRING db_name= { table->db, table->db_length }; LEX_STRING table_name= { table->table_name, table->table_name_length }; if (table->open_type == OT_BASE_ONLY || !thd->find_temporary_table(table)) (void) delete_statistics_for_table(thd, &db_name, &table_name); } } /* mysql_ha_rm_tables() requires a non-null TABLE_LIST. */ if (tables) mysql_ha_rm_tables(thd, tables); for (table= tables; table; table= table->next_local) deleted_tables++; thd->push_internal_handler(&err_handler); if (!thd->killed && !(tables && mysql_rm_table_no_locks(thd, tables, true, false, true, true, false))) { /* We temporarily disable the binary log while dropping the objects in the database. Since the DROP DATABASE statement is always replicated as a statement, execution of it will drop all objects in the database on the slave as well, so there is no need to replicate the removal of the individual objects in the database as well. This is more of a safety precaution, since normally no objects should be dropped while the database is being cleaned, but in the event that a change in the code to remove other objects is made, these drops should still not be logged. */ ha_drop_database(path); tmp_disable_binlog(thd); query_cache_invalidate1(thd, dbnorm); (void) sp_drop_db_routines(thd, dbnorm); /* @todo Do not ignore errors */ #ifdef HAVE_EVENT_SCHEDULER Events::drop_schema_events(thd, dbnorm); #endif reenable_binlog(thd); /* If the directory is a symbolic link, remove the link first, then remove the directory the symbolic link pointed at */ error= rm_dir_w_symlink(path, true); } thd->pop_internal_handler(); update_binlog: if (!silent && !error) { const char *query; ulong query_length; query= thd->query(); query_length= thd->query_length(); DBUG_ASSERT(query); if (mysql_bin_log.is_open()) { int errcode= query_error_code(thd, TRUE); Query_log_event qinfo(thd, query, query_length, FALSE, TRUE, /* suppress_use */ TRUE, errcode); /* Write should use the database being created as the "current database" and not the threads current database, which is the default. */ qinfo.db = db; qinfo.db_len = strlen(db); /* These DDL methods and logging are protected with the exclusive metadata lock on the schema. */ if (mysql_bin_log.write(&qinfo)) { error= true; goto exit; } } thd->clear_error(); thd->server_status|= SERVER_STATUS_DB_DROPPED; my_ok(thd, deleted_tables); } else if (mysql_bin_log.is_open() && !silent) { char *query, *query_pos, *query_end, *query_data_start; TABLE_LIST *tbl; uint db_len; if (!(query= (char*) thd->alloc(MAX_DROP_TABLE_Q_LEN))) goto exit; /* not much else we can do */ query_pos= query_data_start= strmov(query,"DROP TABLE IF EXISTS "); query_end= query + MAX_DROP_TABLE_Q_LEN; db_len= strlen(db); for (tbl= tables; tbl; tbl= tbl->next_local) { uint tbl_name_len; char quoted_name[FN_REFLEN+3]; // Only write drop table to the binlog for tables that no longer exist. if (ha_table_exists(thd, tbl->db, tbl->table_name)) continue; my_snprintf(quoted_name, sizeof(quoted_name), "%`s", tbl->table_name); tbl_name_len= strlen(quoted_name) + 1; /* +1 for the comma */ if (query_pos + tbl_name_len + 1 >= query_end) { /* These DDL methods and logging are protected with the exclusive metadata lock on the schema. */ if (write_to_binlog(thd, query, query_pos -1 - query, db, db_len)) { error= true; goto exit; } query_pos= query_data_start; } query_pos= strmov(query_pos, quoted_name); *query_pos++ = ','; } if (query_pos != query_data_start) { /* These DDL methods and logging are protected with the exclusive metadata lock on the schema. */ if (write_to_binlog(thd, query, query_pos -1 - query, db, db_len)) { error= true; goto exit; } } } exit: /* If this database was the client's selected database, we silently change the client's selected database to nothing (to have an empty SELECT DATABASE() in the future). For this we free() thd->db and set it to 0. */ if (thd->db && cmp_db_names(thd->db, db) && !error) { mysql_change_db_impl(thd, NULL, 0, thd->variables.collation_server); SESSION_TRACKER_CHANGED(thd, CURRENT_SCHEMA_TRACKER, NULL); } my_dirend(dirp); DBUG_RETURN(error); } bool mysql_rm_db(THD *thd,char *db, bool if_exists) { return mysql_rm_db_internal(thd, db, if_exists, false); } static bool find_db_tables_and_rm_known_files(THD *thd, MY_DIR *dirp, char *dbname, const char *path, TABLE_LIST **tables) { char filePath[FN_REFLEN]; LEX_STRING db= { dbname, strlen(dbname) }; TABLE_LIST *tot_list=0, **tot_list_next_local, **tot_list_next_global; DBUG_ENTER("find_db_tables_and_rm_known_files"); DBUG_PRINT("enter",("path: %s", path)); /* first, get the list of tables */ Dynamic_array files(dirp->number_of_files); Discovered_table_list tl(thd, &files); if (ha_discover_table_names(thd, &db, dirp, &tl, true)) DBUG_RETURN(1); /* Now put the tables in the list */ tot_list_next_local= tot_list_next_global= &tot_list; for (size_t idx=0; idx < files.elements(); idx++) { LEX_STRING *table= files.at(idx); /* Drop the table nicely */ TABLE_LIST *table_list=(TABLE_LIST*)thd->calloc(sizeof(*table_list)); if (!table_list) DBUG_RETURN(true); table_list->db= db.str; table_list->db_length= db.length; table_list->table_name= table->str; table_list->table_name_length= table->length; table_list->open_type= OT_BASE_ONLY; /* To be able to correctly look up the table in the table cache. */ if (lower_case_table_names) table_list->table_name_length= my_casedn_str(files_charset_info, table_list->table_name); table_list->alias= table_list->table_name; // If lower_case_table_names=2 table_list->mdl_request.init(MDL_key::TABLE, table_list->db, table_list->table_name, MDL_EXCLUSIVE, MDL_TRANSACTION); /* Link into list */ (*tot_list_next_local)= table_list; (*tot_list_next_global)= table_list; tot_list_next_local= &table_list->next_local; tot_list_next_global= &table_list->next_global; } *tables= tot_list; /* and at last delete all non-table files */ for (uint idx=0 ; idx < (uint) dirp->number_of_files && !thd->killed ; idx++) { FILEINFO *file=dirp->dir_entry+idx; char *extension; DBUG_PRINT("info",("Examining: %s", file->name)); if (file->name[0] == 'a' && file->name[1] == 'r' && file->name[2] == 'c' && file->name[3] == '\0') { /* .frm archive: Those archives are obsolete, but following code should exist to remove existent "arc" directories. */ char newpath[FN_REFLEN]; MY_DIR *new_dirp; strxmov(newpath, path, "/", "arc", NullS); (void) unpack_filename(newpath, newpath); if ((new_dirp = my_dir(newpath, MYF(MY_DONT_SORT)))) { DBUG_PRINT("my",("Archive subdir found: %s", newpath)); if ((mysql_rm_arc_files(thd, new_dirp, newpath)) < 0) DBUG_RETURN(true); } continue; } if (!(extension= strrchr(file->name, '.'))) extension= strend(file->name); if (find_type(extension, &deletable_extentions, FIND_TYPE_NO_PREFIX) > 0) { strxmov(filePath, path, "/", file->name, NullS); /* We ignore ENOENT error in order to skip files that was deleted by concurrently running statement like REAPIR TABLE ... */ if (my_delete_with_symlink(filePath, MYF(0)) && my_errno != ENOENT) { my_error(EE_DELETE, MYF(0), filePath, my_errno); DBUG_RETURN(true); } } } DBUG_RETURN(false); } /* Remove directory with symlink SYNOPSIS rm_dir_w_symlink() org_path path of derictory send_error send errors RETURN 0 OK 1 ERROR */ static my_bool rm_dir_w_symlink(const char *org_path, my_bool send_error) { char tmp_path[FN_REFLEN], *pos; char *path= tmp_path; DBUG_ENTER("rm_dir_w_symlink"); unpack_filename(tmp_path, org_path); #ifdef HAVE_READLINK int error; char tmp2_path[FN_REFLEN]; /* Remove end FN_LIBCHAR as this causes problem on Linux in readlink */ pos= strend(path); if (pos > path && pos[-1] == FN_LIBCHAR) *--pos=0; if ((error= my_readlink(tmp2_path, path, MYF(MY_WME))) < 0) DBUG_RETURN(1); if (!error) { if (mysql_file_delete(key_file_misc, path, MYF(send_error ? MY_WME : 0))) { DBUG_RETURN(send_error); } /* Delete directory symbolic link pointed at */ path= tmp2_path; } #endif /* Remove last FN_LIBCHAR to not cause a problem on OS/2 */ pos= strend(path); if (pos > path && pos[-1] == FN_LIBCHAR) *--pos=0; if (rmdir(path) < 0 && send_error) { my_error(ER_DB_DROP_RMDIR, MYF(0), path, errno); DBUG_RETURN(1); } DBUG_RETURN(0); } /* Remove .frm archives from directory SYNOPSIS thd thread handler dirp list of files in archive directory db data base name org_path path of archive directory RETURN > 0 number of removed files -1 error NOTE A support of "arc" directories is obsolete, however this function should exist to remove existent "arc" directories. */ long mysql_rm_arc_files(THD *thd, MY_DIR *dirp, const char *org_path) { long deleted= 0; ulong found_other_files= 0; char filePath[FN_REFLEN]; DBUG_ENTER("mysql_rm_arc_files"); DBUG_PRINT("enter", ("path: %s", org_path)); for (uint idx=0 ; idx < (uint) dirp->number_of_files && !thd->killed ; idx++) { FILEINFO *file=dirp->dir_entry+idx; char *extension, *revision; DBUG_PRINT("info",("Examining: %s", file->name)); extension= fn_ext(file->name); if (extension[0] != '.' || extension[1] != 'f' || extension[2] != 'r' || extension[3] != 'm' || extension[4] != '-') { found_other_files++; continue; } revision= extension+5; while (*revision && my_isdigit(system_charset_info, *revision)) revision++; if (*revision) { found_other_files++; continue; } strxmov(filePath, org_path, "/", file->name, NullS); if (mysql_file_delete_with_symlink(key_file_misc, filePath, MYF(MY_WME))) { goto err; } deleted++; } if (thd->killed) goto err; my_dirend(dirp); /* If the directory is a symbolic link, remove the link first, then remove the directory the symbolic link pointed at */ if (!found_other_files && rm_dir_w_symlink(org_path, 0)) DBUG_RETURN(-1); DBUG_RETURN(deleted); err: my_dirend(dirp); DBUG_RETURN(-1); } /** @brief Internal implementation: switch current database to a valid one. @param thd Thread context. @param new_db_name Name of the database to switch to. The function will take ownership of the name (the caller must not free the allocated memory). If the name is NULL, we're going to switch to NULL db. @param new_db_access Privileges of the new database. @param new_db_charset Character set of the new database. */ static void mysql_change_db_impl(THD *thd, LEX_STRING *new_db_name, ulong new_db_access, CHARSET_INFO *new_db_charset) { /* 1. Change current database in THD. */ if (new_db_name == NULL) { /* THD::set_db() does all the job -- it frees previous database name and sets the new one. */ thd->set_db(NULL, 0); } else if (new_db_name == &INFORMATION_SCHEMA_NAME) { /* Here we must use THD::set_db(), because we want to copy INFORMATION_SCHEMA_NAME constant. */ thd->set_db(INFORMATION_SCHEMA_NAME.str, INFORMATION_SCHEMA_NAME.length); } else { /* Here we already have a copy of database name to be used in THD. So, we just call THD::reset_db(). Since THD::reset_db() does not releases the previous database name, we should do it explicitly. */ thd->set_db(NULL, 0); thd->reset_db(new_db_name->str, new_db_name->length); } /* 2. Update security context. */ #ifndef NO_EMBEDDED_ACCESS_CHECKS thd->security_ctx->db_access= new_db_access; #endif /* 3. Update db-charset environment variables. */ thd->db_charset= new_db_charset; thd->variables.collation_database= new_db_charset; } /** Backup the current database name before switch. @param[in] thd thread handle @param[in, out] saved_db_name IN: "str" points to a buffer where to store the old database name, "length" contains the buffer size OUT: if the current (default) database is not NULL, its name is copied to the buffer pointed at by "str" and "length" is updated accordingly. Otherwise "str" is set to NULL and "length" is set to 0. */ static void backup_current_db_name(THD *thd, LEX_STRING *saved_db_name) { if (!thd->db) { /* No current (default) database selected. */ saved_db_name->str= NULL; saved_db_name->length= 0; } else { strmake(saved_db_name->str, thd->db, saved_db_name->length - 1); saved_db_name->length= thd->db_length; } } /** @brief Change the current database and its attributes unconditionally. @param thd thread handle @param new_db_name database name @param force_switch if force_switch is FALSE, then the operation will fail if - new_db_name is NULL or empty; - OR new database name is invalid (check_db_name() failed); - OR user has no privilege on the new database; - OR new database does not exist; if force_switch is TRUE, then - if new_db_name is NULL or empty, the current database will be NULL, @@collation_database will be set to @@collation_server, the operation will succeed. - if new database name is invalid (check_db_name() failed), the current database will be NULL, @@collation_database will be set to @@collation_server, but the operation will fail; - user privileges will not be checked (THD::db_access however is updated); TODO: is this really the intention? (see sp-security.test). - if new database does not exist,the current database will be NULL, @@collation_database will be set to @@collation_server, a warning will be thrown, the operation will succeed. @details The function checks that the database name corresponds to a valid and existent database, checks access rights and changes the current database with database attributes (@@collation_database session variable, THD::db_access). This function is not the only way to switch the database that is currently employed. When the replication slave thread switches the database before executing a query, it calls thd->set_db directly. However, if the query, in turn, uses a stored routine, the stored routine will use this function, even if it's run on the slave. This function allocates the name of the database on the system heap: this is necessary to be able to uniformly change the database from any module of the server. Up to 5.0 different modules were using different memory to store the name of the database, and this led to memory corruption: a stack pointer set by Stored Procedures was used by replication after the stack address was long gone. @return Operation status @retval FALSE Success @retval TRUE Error */ bool mysql_change_db(THD *thd, const LEX_STRING *new_db_name, bool force_switch) { LEX_STRING new_db_file_name; Security_context *sctx= thd->security_ctx; ulong db_access= sctx->db_access; CHARSET_INFO *db_default_cl; DBUG_ENTER("mysql_change_db"); if (new_db_name->length == 0) { if (force_switch) { /* This can happen only if we're switching the current database back after loading stored program. The thing is that loading of stored program can happen when there is no current database. In case of stored program, new_db_name->str == "" and new_db_name->length == 0. */ mysql_change_db_impl(thd, NULL, 0, thd->variables.collation_server); goto done; } else { my_message(ER_NO_DB_ERROR, ER_THD(thd, ER_NO_DB_ERROR), MYF(0)); DBUG_RETURN(TRUE); } } DBUG_PRINT("enter",("name: '%s'", new_db_name->str)); if (is_infoschema_db(new_db_name->str, new_db_name->length)) { /* Switch the current database to INFORMATION_SCHEMA. */ mysql_change_db_impl(thd, &INFORMATION_SCHEMA_NAME, SELECT_ACL, system_charset_info); goto done; } /* Now we need to make a copy because check_db_name requires a non-constant argument. Actually, it takes database file name. TODO: fix check_db_name(). */ new_db_file_name.str= my_strndup(new_db_name->str, new_db_name->length, MYF(MY_WME)); new_db_file_name.length= new_db_name->length; if (new_db_file_name.str == NULL) DBUG_RETURN(TRUE); /* the error is set */ /* NOTE: if check_db_name() fails, we should throw an error in any case, even if we are called from sp_head::execute(). It's next to impossible however to get this error when we are called from sp_head::execute(). But let's switch the current database to NULL in this case to be sure. */ if (check_db_name(&new_db_file_name)) { my_error(ER_WRONG_DB_NAME, MYF(0), new_db_file_name.str); my_free(new_db_file_name.str); if (force_switch) mysql_change_db_impl(thd, NULL, 0, thd->variables.collation_server); DBUG_RETURN(TRUE); } DBUG_PRINT("info",("Use database: %s", new_db_file_name.str)); #ifndef NO_EMBEDDED_ACCESS_CHECKS if (test_all_bits(sctx->master_access, DB_ACLS)) db_access= DB_ACLS; else { db_access= acl_get(sctx->host, sctx->ip, sctx->priv_user, new_db_file_name.str, FALSE) | sctx->master_access; if (sctx->priv_role[0]) { /* include a possible currently set role for access */ db_access|= acl_get("", "", sctx->priv_role, new_db_file_name.str, FALSE); } } if (!force_switch && !(db_access & DB_ACLS) && check_grant_db(thd, new_db_file_name.str)) { my_error(ER_DBACCESS_DENIED_ERROR, MYF(0), sctx->priv_user, sctx->priv_host, new_db_file_name.str); general_log_print(thd, COM_INIT_DB, ER_THD(thd, ER_DBACCESS_DENIED_ERROR), sctx->priv_user, sctx->priv_host, new_db_file_name.str); my_free(new_db_file_name.str); DBUG_RETURN(TRUE); } #endif DEBUG_SYNC(thd, "before_db_dir_check"); if (check_db_dir_existence(new_db_file_name.str)) { if (force_switch) { /* Throw a warning and free new_db_file_name. */ push_warning_printf(thd, Sql_condition::WARN_LEVEL_NOTE, ER_BAD_DB_ERROR, ER_THD(thd, ER_BAD_DB_ERROR), new_db_file_name.str); my_free(new_db_file_name.str); /* Change db to NULL. */ mysql_change_db_impl(thd, NULL, 0, thd->variables.collation_server); /* The operation succeed. */ goto done; } else { /* Report an error and free new_db_file_name. */ my_error(ER_BAD_DB_ERROR, MYF(0), new_db_file_name.str); my_free(new_db_file_name.str); /* The operation failed. */ DBUG_RETURN(TRUE); } } /* NOTE: in mysql_change_db_impl() new_db_file_name is assigned to THD attributes and will be freed in THD::~THD(). */ db_default_cl= get_default_db_collation(thd, new_db_file_name.str); mysql_change_db_impl(thd, &new_db_file_name, db_access, db_default_cl); done: SESSION_TRACKER_CHANGED(thd, CURRENT_SCHEMA_TRACKER, NULL); SESSION_TRACKER_CHANGED(thd, SESSION_STATE_CHANGE_TRACKER, NULL); DBUG_RETURN(FALSE); } /** Change the current database and its attributes if needed. @param thd thread handle @param new_db_name database name @param[in, out] saved_db_name IN: "str" points to a buffer where to store the old database name, "length" contains the buffer size OUT: if the current (default) database is not NULL, its name is copied to the buffer pointed at by "str" and "length" is updated accordingly. Otherwise "str" is set to NULL and "length" is set to 0. @param force_switch @see mysql_change_db() @param[out] cur_db_changed out-flag to indicate whether the current database has been changed (valid only if the function suceeded) */ bool mysql_opt_change_db(THD *thd, const LEX_STRING *new_db_name, LEX_STRING *saved_db_name, bool force_switch, bool *cur_db_changed) { *cur_db_changed= !cmp_db_names(thd->db, new_db_name->str); if (!*cur_db_changed) return FALSE; backup_current_db_name(thd, saved_db_name); return mysql_change_db(thd, new_db_name, force_switch); } /** Upgrade a 5.0 database. This function is invoked whenever an ALTER DATABASE UPGRADE query is executed: ALTER DATABASE 'olddb' UPGRADE DATA DIRECTORY NAME. If we have managed to rename (move) tables to the new database but something failed on a later step, then we store the RENAME DATABASE event in the log. mysql_rename_db() is atomic in the sense that it will rename all or none of the tables. @param thd Current thread @param old_db 5.0 database name, in #mysql50#name format @return 0 on success, 1 on error */ bool mysql_upgrade_db(THD *thd, LEX_STRING *old_db) { int error= 0, change_to_newdb= 0; char path[FN_REFLEN+16]; uint length; Schema_specification_st create_info; MY_DIR *dirp; TABLE_LIST *table_list; SELECT_LEX *sl= thd->lex->current_select; LEX_STRING new_db; DBUG_ENTER("mysql_upgrade_db"); if ((old_db->length <= MYSQL50_TABLE_NAME_PREFIX_LENGTH) || (strncmp(old_db->str, MYSQL50_TABLE_NAME_PREFIX, MYSQL50_TABLE_NAME_PREFIX_LENGTH) != 0)) { my_error(ER_WRONG_USAGE, MYF(0), "ALTER DATABASE UPGRADE DATA DIRECTORY NAME", "name"); DBUG_RETURN(1); } /* `#mysql50#` converted to encoded `` */ new_db.str= old_db->str + MYSQL50_TABLE_NAME_PREFIX_LENGTH; new_db.length= old_db->length - MYSQL50_TABLE_NAME_PREFIX_LENGTH; /* Lock the old name, the new name will be locked by mysql_create_db().*/ if (lock_schema_name(thd, old_db->str)) DBUG_RETURN(1); /* Let's remember if we should do "USE newdb" afterwards. thd->db will be cleared in mysql_rename_db() */ if (thd->db && !strcmp(thd->db, old_db->str)) change_to_newdb= 1; build_table_filename(path, sizeof(path)-1, old_db->str, "", MY_DB_OPT_FILE, 0); if ((load_db_opt(thd, path, &create_info))) create_info.default_table_charset= thd->variables.collation_server; length= build_table_filename(path, sizeof(path)-1, old_db->str, "", "", 0); if (length && path[length-1] == FN_LIBCHAR) path[length-1]=0; // remove ending '\' if ((error= my_access(path,F_OK))) { my_error(ER_BAD_DB_ERROR, MYF(0), old_db->str); goto exit; } /* Step1: Create the new database */ if ((error= mysql_create_db_internal(thd, new_db.str, DDL_options(), &create_info, 1))) goto exit; /* Step2: Move tables to the new database */ if ((dirp = my_dir(path,MYF(MY_DONT_SORT)))) { uint nfiles= (uint) dirp->number_of_files; for (uint idx=0 ; idx < nfiles && !thd->killed ; idx++) { FILEINFO *file= dirp->dir_entry + idx; char *extension, tname[FN_REFLEN + 1]; LEX_STRING table_str; DBUG_PRINT("info",("Examining: %s", file->name)); /* skiping non-FRM files */ if (my_strcasecmp(files_charset_info, (extension= fn_rext(file->name)), reg_ext)) continue; /* A frm file found, add the table info rename list */ *extension= '\0'; table_str.length= filename_to_tablename(file->name, tname, sizeof(tname)-1); table_str.str= (char*) thd->memdup(tname, table_str.length + 1); Table_ident *old_ident= new Table_ident(thd, *old_db, table_str, 0); Table_ident *new_ident= new Table_ident(thd, new_db, table_str, 0); if (!old_ident || !new_ident || !sl->add_table_to_list(thd, old_ident, NULL, TL_OPTION_UPDATING, TL_IGNORE, MDL_EXCLUSIVE) || !sl->add_table_to_list(thd, new_ident, NULL, TL_OPTION_UPDATING, TL_IGNORE, MDL_EXCLUSIVE)) { error= 1; my_dirend(dirp); goto exit; } } my_dirend(dirp); } if ((table_list= thd->lex->query_tables) && (error= mysql_rename_tables(thd, table_list, 1))) { /* Failed to move all tables from the old database to the new one. In the best case mysql_rename_tables() moved all tables back to the old database. In the worst case mysql_rename_tables() moved some tables to the new database, then failed, then started to move the tables back, and then failed again. In this situation we have some tables in the old database and some tables in the new database. Let's delete the option file, and then the new database directory. If some tables were left in the new directory, rmdir() will fail. It garantees we never loose any tables. */ build_table_filename(path, sizeof(path)-1, new_db.str,"",MY_DB_OPT_FILE, 0); mysql_file_delete(key_file_dbopt, path, MYF(MY_WME)); length= build_table_filename(path, sizeof(path)-1, new_db.str, "", "", 0); if (length && path[length-1] == FN_LIBCHAR) path[length-1]=0; // remove ending '\' rmdir(path); goto exit; } /* Step3: move all remaining files to the new db's directory. Skip db opt file: it's been created by mysql_create_db() in the new directory, and will be dropped by mysql_rm_db() in the old one. Trigger TRN and TRG files are be moved as regular files at the moment, without any special treatment. Triggers without explicit database qualifiers in table names work fine: use d1; create trigger trg1 before insert on t2 for each row set @a:=1 rename database d1 to d2; TODO: Triggers, having the renamed database explicitly written in the table qualifiers. 1. when the same database is renamed: create trigger d1.trg1 before insert on d1.t1 for each row set @a:=1; rename database d1 to d2; Problem: After database renaming, the trigger's body still points to the old database d1. 2. when another database is renamed: create trigger d3.trg1 before insert on d3.t1 for each row insert into d1.t1 values (...); rename database d1 to d2; Problem: After renaming d1 to d2, the trigger's body in the database d3 still points to database d1. */ if ((dirp = my_dir(path,MYF(MY_DONT_SORT)))) { uint nfiles= (uint) dirp->number_of_files; for (uint idx=0 ; idx < nfiles ; idx++) { FILEINFO *file= dirp->dir_entry + idx; char oldname[FN_REFLEN + 1], newname[FN_REFLEN + 1]; DBUG_PRINT("info",("Examining: %s", file->name)); /* skiping MY_DB_OPT_FILE */ if (!my_strcasecmp(files_charset_info, file->name, MY_DB_OPT_FILE)) continue; /* pass empty file name, and file->name as extension to avoid encoding */ build_table_filename(oldname, sizeof(oldname)-1, old_db->str, "", file->name, 0); build_table_filename(newname, sizeof(newname)-1, new_db.str, "", file->name, 0); mysql_file_rename(key_file_misc, oldname, newname, MYF(MY_WME)); } my_dirend(dirp); } /* Step7: drop the old database. query_cache_invalidate(olddb) is done inside mysql_rm_db(), no need to execute them again. mysql_rm_db() also "unuses" if we drop the current database. */ error= mysql_rm_db_internal(thd, old_db->str, 0, true); /* Step8: logging */ if (mysql_bin_log.is_open()) { int errcode= query_error_code(thd, TRUE); Query_log_event qinfo(thd, thd->query(), thd->query_length(), FALSE, TRUE, TRUE, errcode); thd->clear_error(); error|= mysql_bin_log.write(&qinfo); } /* Step9: Let's do "use newdb" if we renamed the current database */ if (change_to_newdb) error|= mysql_change_db(thd, & new_db, FALSE); exit: DBUG_RETURN(error); } /* Check if there is directory for the database name. SYNOPSIS check_db_dir_existence() db_name database name RETURN VALUES FALSE There is directory for the specified database name. TRUE The directory does not exist. */ bool check_db_dir_existence(const char *db_name) { char db_dir_path[FN_REFLEN + 1]; uint db_dir_path_len; db_dir_path_len= build_table_filename(db_dir_path, sizeof(db_dir_path) - 1, db_name, "", "", 0); if (db_dir_path_len && db_dir_path[db_dir_path_len - 1] == FN_LIBCHAR) db_dir_path[db_dir_path_len - 1]= 0; /* Check access. */ return my_access(db_dir_path, F_OK); }