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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-04 18:07:14 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-04 18:07:14 +0000 |
commit | a175314c3e5827eb193872241446f2f8f5c9d33c (patch) | |
tree | cd3d60ca99ae00829c52a6ca79150a5b6e62528b /sql/sql_db.cc | |
parent | Initial commit. (diff) | |
download | mariadb-10.5-upstream/1%10.5.12.tar.xz mariadb-10.5-upstream/1%10.5.12.zip |
Adding upstream version 1:10.5.12.upstream/1%10.5.12upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | sql/sql_db.cc | 1947 |
1 files changed, 1947 insertions, 0 deletions
diff --git a/sql/sql_db.cc b/sql/sql_db.cc new file mode 100644 index 00000000..3447032f --- /dev/null +++ b/sql/sql_db.cc @@ -0,0 +1,1947 @@ +/* + 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 02110-1335 USA */ + + +/* create and drop of databases */ + +#include "mariadb.h" /* 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 + // validate_comment_length +#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 +#include "sql_handler.h" // mysql_ha_rm_tables +#include "sql_class.h" +#include <mysys_err.h> +#include "sp_head.h" +#include "sp.h" +#include "events.h" +#include "sql_handler.h" +#include "sql_statistics.h" +#include <my_dir.h> +#include <m_ctype.h> +#include "log.h" +#ifdef __WIN__ +#include <direct.h> +#endif +#include "debug_sync.h" + +#define MAX_DROP_TABLE_Q_LEN 1024 + +const char *del_exts[]= {".BAK", ".opt", NullS}; +static TYPELIB deletable_extensions= +{array_elements(del_exts)-1,"del_exts", del_exts, NULL}; + +static bool find_db_tables_and_rm_known_files(THD *, MY_DIR *, const 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_CSTRING *new_db_name, + privilege_t new_db_access, + CHARSET_INFO *new_db_charset); +static bool mysql_rm_db_internal(THD *thd, const LEX_CSTRING *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 */ + LEX_STRING comment; /* Database comment */ +} 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(LEX_CSTRING *db1_name, const LEX_CSTRING *db2_name) +{ + return (db1_name->length == db2_name->length && + (db1_name->length == 0 || + my_strcasecmp(table_alias_charset, + db1_name->str, db2_name->str) == 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, const char *query, size_t q_len, + const char *db, size_t db_len) +{ + Query_log_event qinfo(thd, query, q_len, FALSE, TRUE, FALSE, 0); + qinfo.db= db; + qinfo.db_len= (uint32)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(key_memory_dboptions_hash, &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(key_memory_dboptions_hash, &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(THD *thd, 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; + if (opt->comment.length) + { + create->schema_comment= thd->make_clex_string(opt->comment.str, + opt->comment.length); + } + 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; + char *tmp_comment= NULL; + if (!my_multi_malloc(key_memory_dboptions_hash, MYF(MY_WME | MY_ZEROFILL), + &opt, (uint) sizeof(*opt), &tmp_name, (uint) length+1, + &tmp_comment, (uint) DATABASE_COMMENT_MAXLEN+1, + NullS)) + { + error= 1; + goto end; + } + + opt->name= tmp_name; + strmov(opt->name, dbname); + opt->name_length= length; + opt->comment.str= tmp_comment; + if (unlikely((error= my_hash_insert(&dboptions, (uchar*) opt)))) + { + my_free(opt); + goto end; + } + } + + /* Update / write options in hash */ + opt->charset= create->default_table_charset; + + if (create->schema_comment) + { + strmov(opt->comment.str, create->schema_comment->str); + opt->comment.length= create->schema_comment->length; + } + +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, default collation + and comment are 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) +{ + File file; + char buf[256+DATABASE_COMMENT_MAXLEN]; + bool error=1; + + if (create->schema_comment) + { + if (validate_comment_length(thd, create->schema_comment, + DATABASE_COMMENT_MAXLEN, + ER_TOO_LONG_DATABASE_COMMENT, + thd->lex->name.str)) + return error; + } + + if (thd->lex->sql_command == SQLCOM_ALTER_DB && + (!create->schema_comment || !create->default_table_charset)) + { + /* Use existing values of schema_comment and charset for + ALTER DATABASE queries */ + Schema_specification_st tmp; + tmp.init(); + load_db_opt(thd, path, &tmp); + + if (!create->schema_comment) + create->schema_comment= tmp.schema_comment; + + if (!create->default_table_charset) + create->default_table_charset= tmp.default_table_charset; + } + + 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); + + if (create->schema_comment) + length= (ulong) (strxnmov(buf+length, sizeof(buf)-1-length, + "comment=", create->schema_comment->str, + "\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+DATABASE_COMMENT_MAXLEN]; + DBUG_ENTER("load_db_opt"); + bool error=1; + size_t 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(thd, 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; + } + } + else if (!strncmp(buf, "comment", (pos-buf))) + create->schema_comment= thd->make_clex_string(pos+1, strlen(pos+1)); + } + } + /* + 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.str != NULL && strcmp(db_name, thd->db.str) == 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_internal() + 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, const LEX_CSTRING *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->str); + DBUG_RETURN(-1); + } + + char db_tmp[SAFE_NAME_LEN+1]; + const char *dbnorm= normalize_db_name(db->str, db_tmp, sizeof(db_tmp)); + + if (lock_schema_name(thd, dbnorm)) + DBUG_RETURN(-1); + + /* Check directory */ + path_len= build_table_filename(path, sizeof(path) - 1, db->str, "", "", 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->str); + affected_rows= 0; + goto not_silent; + } + else + { + my_error(ER_DB_CREATE_EXISTS, MYF(0), db->str); + DBUG_RETURN(-1); + } + + + if (my_mkdir(path, 0777, MYF(0)) < 0) + { + my_error(ER_CANT_CREATE_DB, MYF(0), db->str, 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->str; + qinfo.db_len = (uint32)db->length; + + /* + 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 LEX_CSTRING *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->str)) + 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->str, "", MY_DB_OPT_FILE, 0); + if (unlikely((error=write_db_opt(thd, path, create_info)))) + goto exit; + + /* Change options if current database is being altered. */ + + if (thd->db.str && !cmp(&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->str; + qinfo.db_len= (uint)db->length; + + /* + These DDL methods and logging are protected with the exclusive + metadata lock on the schema. + */ + if (unlikely((error= mysql_bin_log.write(&qinfo)))) + goto exit; + } + my_ok(thd, result); + +exit: + DBUG_RETURN(error); +} + + +int mysql_create_db(THD *thd, const LEX_CSTRING *db, 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); + if (thd->slave_thread && + slave_ddl_exec_mode_options == SLAVE_EXEC_MODE_IDEMPOTENT) + options.add(DDL_options::OPT_IF_NOT_EXISTS); + return mysql_create_db_internal(thd, db, options, &tmp, false); +} + + +bool mysql_alter_db(THD *thd, const LEX_CSTRING *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, const LEX_CSTRING *db, bool if_exists, bool silent) +{ + ulong deleted_tables= 0; + bool error= true, rm_mysql_schema; + 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+1]; + const char *dbnorm= normalize_db_name(db->str, db_tmp, sizeof(db_tmp)); + + if (lock_schema_name(thd, dbnorm)) + DBUG_RETURN(true); + + length= build_table_filename(path, sizeof(path) - 1, db->str, "", "", 0); + strmov(path+length, MY_DB_OPT_FILE); // Append db option file name + del_dbopt(path); // Remove dboption hash entry + /* + Now remove the db.opt file. + The 'find_db_tables_and_rm_known_files' doesn't remove this file + if there exists a table with the name 'db', so let's just do it + separately. We know this file exists and needs to be deleted anyway. + */ + if (mysql_file_delete_with_symlink(key_file_misc, path, "", MYF(0)) && + my_errno != ENOENT) + { + my_error(EE_DELETE, MYF(0), path, my_errno); + DBUG_RETURN(true); + } + + 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->str); + 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->str); + 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 ((rm_mysql_schema= + (my_strcasecmp(system_charset_info, MYSQL_SCHEMA_NAME.str, db->str) == 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 (!rm_mysql_schema) + { + for (table= tables; table; table= table->next_local) + { + if (table->open_type == OT_BASE_ONLY || + !thd->find_temporary_table(table)) + (void) delete_statistics_for_table(thd, &table->db, &table->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, false, 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); + if (!rm_mysql_schema) + { + (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 && likely(!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->str; + qinfo.db_len = (uint32)db->length; + + /* + 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; + + 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; + + for (tbl= tables; tbl; tbl= tbl->next_local) + { + size_t 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; + + tbl_name_len= my_snprintf(quoted_name, sizeof(quoted_name), "%`s", + tbl->table_name.str); + tbl_name_len++; /* +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, (uint)(query_pos -1 - query), db->str, db->length)) + { + 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, (uint)(query_pos -1 - query), db->str, db->length)) + { + 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 (unlikely(thd->db.str && cmp_db_names(&thd->db, db) && !error)) + { + mysql_change_db_impl(thd, NULL, NO_ACL, thd->variables.collation_server); + thd->session_tracker.current_schema.mark_as_changed(thd); + } + my_dirend(dirp); + DBUG_RETURN(error); +} + + +bool mysql_rm_db(THD *thd, const LEX_CSTRING *db, bool if_exists) +{ + if (thd->slave_thread && + slave_ddl_exec_mode_options == SLAVE_EXEC_MODE_IDEMPOTENT) + if_exists= true; + return mysql_rm_db_internal(thd, db, if_exists, false); +} + + +static bool find_db_tables_and_rm_known_files(THD *thd, MY_DIR *dirp, + const char *dbname, + const char *path, + TABLE_LIST **tables) +{ + char filePath[FN_REFLEN]; + LEX_CSTRING 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<LEX_CSTRING*> 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_CSTRING *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; + table_list->table_name= *table; + table_list->open_type= OT_BASE_ONLY; + + /* + On the case-insensitive file systems table is opened + with the lowercased file name. So we should lowercase + as well to look up the cache properly. + */ + if (lower_case_file_system) + table_list->table_name.length= my_casedn_str(files_charset_info, + (char*) table_list->table_name.str); + + table_list->alias= table_list->table_name; // If lower_case_table_names=2 + MDL_REQUEST_INIT(&table_list->mdl_request, MDL_key::TABLE, + table_list->db.str, table_list->table_name.str, + 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_extensions, 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 REPAIR TABLE ... + */ + if (mysql_file_delete_with_symlink(key_file_misc, 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 (unlikely((error= my_readlink(tmp2_path, path, MYF(MY_WME))) < 0)) + DBUG_RETURN(1); + if (likely(!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 (unlikely(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_CSTRING *new_db_name, + privilege_t 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_clex_str); + } + else if (new_db_name->str == INFORMATION_SCHEMA_NAME.str) + { + /* + Here we must use THD::set_db(), because we want to copy + INFORMATION_SCHEMA_NAME constant. + */ + + thd->set_db(&INFORMATION_SCHEMA_NAME); + } + 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_clex_str); + thd->reset_db(new_db_name); + } + + /* 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) +{ + DBUG_ASSERT(saved_db_name->length >= SAFE_NAME_LEN +1); + if (!thd->db.str) + { + /* No current (default) database selected. */ + saved_db_name->str= 0; + saved_db_name->length= 0; + } + else + { + memcpy(saved_db_name->str, thd->db.str, thd->db.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 error code (ER_XXX) + @retval 0 Success + @retval >0 Error +*/ + +uint mysql_change_db(THD *thd, const LEX_CSTRING *new_db_name, + bool force_switch) +{ + LEX_CSTRING new_db_file_name; + + Security_context *sctx= thd->security_ctx; + privilege_t 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, NO_ACL, thd->variables.collation_server); + + goto done; + } + else + { + my_message(ER_NO_DB_ERROR, ER_THD(thd, ER_NO_DB_ERROR), MYF(0)); + + DBUG_RETURN(ER_NO_DB_ERROR); + } + } + DBUG_PRINT("enter",("name: '%s'", new_db_name->str)); + + if (is_infoschema_db(new_db_name)) + { + /* 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(key_memory_THD_db, 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(ER_OUT_OF_RESOURCES); /* 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. + The cast below ok here as new_db_file_name was just allocated + */ + + if (check_db_name((LEX_STRING*) &new_db_file_name)) + { + my_error(ER_WRONG_DB_NAME, MYF(0), new_db_file_name.str); + my_free(const_cast<char*>(new_db_file_name.str)); + + if (force_switch) + mysql_change_db_impl(thd, NULL, NO_ACL, thd->variables.collation_server); + + DBUG_RETURN(ER_WRONG_DB_NAME); + } + + 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(const_cast<char*>(new_db_file_name.str)); + DBUG_RETURN(ER_DBACCESS_DENIED_ERROR); + } +#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(const_cast<char*>(new_db_file_name.str)); + + /* Change db to NULL. */ + + mysql_change_db_impl(thd, NULL, NO_ACL, 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(const_cast<char*>(new_db_file_name.str)); + + /* The operation failed. */ + + DBUG_RETURN(ER_BAD_DB_ERROR); + } + } + + /* + 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: + thd->session_tracker.current_schema.mark_as_changed(thd); + thd->session_tracker.state_change.mark_as_changed(thd); + DBUG_RETURN(0); +} + + +/** + 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_CSTRING *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); + + 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, const LEX_CSTRING *old_db) +{ + bool 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_CSTRING 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#<name>` converted to encoded `<name>` */ + 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.str && !cmp(&thd->db, old_db)) + 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 (unlikely((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 (unlikely((error= mysql_create_db_internal(thd, &new_db, + 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_CSTRING table_str; + DBUG_PRINT("info",("Examining: %s", file->name)); + + /* skiping non-FRM files */ + if (!(extension= (char*) fn_frm_ext(file->name))) + 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, 0))) + { + /* + 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, 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) != 0; + +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); +} + + +const char *normalize_db_name(const char *db, char *buffer, size_t buffer_size) +{ + DBUG_ASSERT(buffer_size > 1); + if (!lower_case_table_names) + return db; + strmake(buffer, db, buffer_size - 1); + my_casedn_str(system_charset_info, buffer); + return buffer; +} |