/* Copyright (C) 2000 MySQL AB & MySQL Finland AB & TCX DataKonsult AB This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ /* Classes in mysql */ #ifdef __GNUC__ #pragma interface /* gcc class implementation */ #endif // TODO: create log.h and move all the log header stuff there class Query_log_event; class Load_log_event; class Slave_log_event; class Format_description_log_event; class sp_rcontext; class sp_cache; enum enum_enable_or_disable { LEAVE_AS_IS, ENABLE, DISABLE }; enum enum_ha_read_modes { RFIRST, RNEXT, RPREV, RLAST, RKEY, RNEXT_SAME }; enum enum_duplicates { DUP_ERROR, DUP_REPLACE, DUP_IGNORE, DUP_UPDATE }; enum enum_log_type { LOG_CLOSED, LOG_TO_BE_OPENED, LOG_NORMAL, LOG_NEW, LOG_BIN}; enum enum_delay_key_write { DELAY_KEY_WRITE_NONE, DELAY_KEY_WRITE_ON, DELAY_KEY_WRITE_ALL }; enum enum_check_fields { CHECK_FIELD_IGNORE, CHECK_FIELD_WARN, CHECK_FIELD_ERROR_FOR_NULL }; extern char internal_table_name[2]; /* log info errors */ #define LOG_INFO_EOF -1 #define LOG_INFO_IO -2 #define LOG_INFO_INVALID -3 #define LOG_INFO_SEEK -4 #define LOG_INFO_MEM -6 #define LOG_INFO_FATAL -7 #define LOG_INFO_IN_USE -8 /* bitmap to SQL_LOG::close() */ #define LOG_CLOSE_INDEX 1 #define LOG_CLOSE_TO_BE_OPENED 2 #define LOG_CLOSE_STOP_EVENT 4 struct st_relay_log_info; typedef struct st_log_info { char log_file_name[FN_REFLEN]; my_off_t index_file_offset, index_file_start_offset; my_off_t pos; bool fatal; // if the purge happens to give us a negative offset pthread_mutex_t lock; st_log_info():fatal(0) { pthread_mutex_init(&lock, MY_MUTEX_INIT_FAST);} ~st_log_info() { pthread_mutex_destroy(&lock);} } LOG_INFO; typedef struct st_user_var_events { user_var_entry *user_var_event; char *value; ulong length; Item_result type; uint charset_number; } BINLOG_USER_VAR_EVENT; class Log_event; class MYSQL_LOG { private: /* LOCK_log and LOCK_index are inited by init_pthread_objects() */ pthread_mutex_t LOCK_log, LOCK_index; pthread_cond_t update_cond; ulonglong bytes_written; time_t last_time,query_start; IO_CACHE log_file; IO_CACHE index_file; char *name; char time_buff[20],db[NAME_LEN+1]; char log_file_name[FN_REFLEN],index_file_name[FN_REFLEN]; // current file sequence number for load data infile binary logging uint file_id; uint open_count; // For replication volatile enum_log_type log_type; enum cache_type io_cache_type; bool write_error, inited; bool need_start_event; /* no_auto_events means we don't want any of these automatic events : Start/Rotate/Stop. That is, in 4.x when we rotate a relay log, we don't want a Rotate_log event to be written to the relay log. When we start a relay log etc. So in 4.x this is 1 for relay logs, 0 for binlogs. In 5.0 it's 0 for relay logs too! */ bool no_auto_events; /* The max size before rotation (usable only if log_type == LOG_BIN: binary logs and relay logs). For a binlog, max_size should be max_binlog_size. For a relay log, it should be max_relay_log_size if this is non-zero, max_binlog_size otherwise. max_size is set in init(), and dynamically changed (when one does SET GLOBAL MAX_BINLOG_SIZE|MAX_RELAY_LOG_SIZE) by fix_max_binlog_size and fix_max_relay_log_size). */ ulong max_size; friend class Log_event; public: MYSQL_LOG(); ~MYSQL_LOG(); /* These describe the log's format. This is used only for relay logs. _for_exec is used by the SQL thread, _for_queue by the I/O thread. It's necessary to have 2 distinct objects, because the I/O thread may be reading events in a different format from what the SQL thread is reading (consider the case of a master which has been upgraded from 5.0 to 5.1 without doing RESET MASTER, or from 4.x to 5.0). */ Format_description_log_event *description_event_for_exec, *description_event_for_queue; void reset_bytes_written() { bytes_written = 0; } void harvest_bytes_written(ulonglong* counter) { #ifndef DBUG_OFF char buf1[22],buf2[22]; #endif DBUG_ENTER("harvest_bytes_written"); (*counter)+=bytes_written; DBUG_PRINT("info",("counter: %s bytes_written: %s", llstr(*counter,buf1), llstr(bytes_written,buf2))); bytes_written=0; DBUG_VOID_RETURN; } void set_max_size(ulong max_size_arg); void signal_update() { pthread_cond_broadcast(&update_cond);} void wait_for_update(THD* thd, bool master_or_slave); void set_need_start_event() { need_start_event = 1; } void init(enum_log_type log_type_arg, enum cache_type io_cache_type_arg, bool no_auto_events_arg, ulong max_size); void init_pthread_objects(); void cleanup(); bool open(const char *log_name,enum_log_type log_type, const char *new_name, const char *index_file_name_arg, enum cache_type io_cache_type_arg, bool no_auto_events_arg, ulong max_size, bool null_created); void new_file(bool need_lock= 1); bool write(THD *thd, enum enum_server_command command, const char *format,...); bool write(THD *thd, const char *query, uint query_length, time_t query_start=0); bool write(Log_event* event_info); // binary log write bool write(THD *thd, IO_CACHE *cache, bool commit_or_rollback); /* v stands for vector invoked as appendv(buf1,len1,buf2,len2,...,bufn,lenn,0) */ bool appendv(const char* buf,uint len,...); bool append(Log_event* ev); int generate_new_name(char *new_name,const char *old_name); void make_log_name(char* buf, const char* log_ident); bool is_active(const char* log_file_name); int update_log_index(LOG_INFO* linfo, bool need_update_threads); int purge_logs(const char *to_log, bool included, bool need_mutex, bool need_update_threads, ulonglong *decrease_log_space); int purge_logs_before_date(time_t purge_time); int purge_first_log(struct st_relay_log_info* rli, bool included); bool reset_logs(THD* thd); void close(uint exiting); bool cut_spurious_tail(); void report_pos_in_innodb(); // iterating through the log index file int find_log_pos(LOG_INFO* linfo, const char* log_name, bool need_mutex); int find_next_log(LOG_INFO* linfo, bool need_mutex); int get_current_log(LOG_INFO* linfo); uint next_file_id(); inline bool is_open() { return log_type != LOG_CLOSED; } inline char* get_index_fname() { return index_file_name;} inline char* get_log_fname() { return log_file_name; } inline pthread_mutex_t* get_log_lock() { return &LOCK_log; } inline IO_CACHE* get_log_file() { return &log_file; } inline void lock_index() { pthread_mutex_lock(&LOCK_index);} inline void unlock_index() { pthread_mutex_unlock(&LOCK_index);} inline IO_CACHE *get_index_file() { return &index_file;} inline uint32 get_open_count() { return open_count; } }; /* character conversion tables */ typedef struct st_copy_info { ha_rows records; ha_rows deleted; ha_rows updated; ha_rows copied; ha_rows error_count; enum enum_duplicates handle_duplicates; int escape_char, last_errno; /* for INSERT ... UPDATE */ List<Item> *update_fields; List<Item> *update_values; /* for VIEW ... WITH CHECK OPTION */ TABLE_LIST *view; bool ignore; } COPY_INFO; class key_part_spec :public Sql_alloc { public: const char *field_name; uint length; key_part_spec(const char *name,uint len=0) :field_name(name), length(len) {} bool operator==(const key_part_spec& other) const; }; class Alter_drop :public Sql_alloc { public: enum drop_type {KEY, COLUMN }; const char *name; enum drop_type type; Alter_drop(enum drop_type par_type,const char *par_name) :name(par_name), type(par_type) {} }; class Alter_column :public Sql_alloc { public: const char *name; Item *def; Alter_column(const char *par_name,Item *literal) :name(par_name), def(literal) {} }; class Key :public Sql_alloc { public: enum Keytype { PRIMARY, UNIQUE, MULTIPLE, FULLTEXT, SPATIAL, FOREIGN_KEY}; enum Keytype type; enum ha_key_alg algorithm; List<key_part_spec> columns; const char *name; bool generated; Key(enum Keytype type_par, const char *name_arg, enum ha_key_alg alg_par, bool generated_arg, List<key_part_spec> &cols) :type(type_par), algorithm(alg_par), columns(cols), name(name_arg), generated(generated_arg) {} ~Key() {} /* Equality comparison of keys (ignoring name) */ friend bool foreign_key_prefix(Key *a, Key *b); }; class Table_ident; class foreign_key: public Key { public: enum fk_match_opt { FK_MATCH_UNDEF, FK_MATCH_FULL, FK_MATCH_PARTIAL, FK_MATCH_SIMPLE}; enum fk_option { FK_OPTION_UNDEF, FK_OPTION_RESTRICT, FK_OPTION_CASCADE, FK_OPTION_SET_NULL, FK_OPTION_NO_ACTION, FK_OPTION_DEFAULT}; Table_ident *ref_table; List<key_part_spec> ref_columns; uint delete_opt, update_opt, match_opt; foreign_key(const char *name_arg, List<key_part_spec> &cols, Table_ident *table, List<key_part_spec> &ref_cols, uint delete_opt_arg, uint update_opt_arg, uint match_opt_arg) :Key(FOREIGN_KEY, name_arg, HA_KEY_ALG_UNDEF, 0, cols), ref_table(table), ref_columns(cols), delete_opt(delete_opt_arg), update_opt(update_opt_arg), match_opt(match_opt_arg) {} }; typedef struct st_mysql_lock { TABLE **table; uint table_count,lock_count; THR_LOCK_DATA **locks; } MYSQL_LOCK; class LEX_COLUMN : public Sql_alloc { public: String column; uint rights; LEX_COLUMN (const String& x,const uint& y ): column (x),rights (y) {} }; #include "sql_lex.h" /* Must be here */ /* Needed to be able to have an I_List of char* strings in mysqld.cc. */ class i_string: public ilink { public: char* ptr; i_string():ptr(0) { } i_string(char* s) : ptr(s) {} }; /* needed for linked list of two strings for replicate-rewrite-db */ class i_string_pair: public ilink { public: char* key; char* val; i_string_pair():key(0),val(0) { } i_string_pair(char* key_arg, char* val_arg) : key(key_arg),val(val_arg) {} }; class MYSQL_ERROR: public Sql_alloc { public: enum enum_warning_level { WARN_LEVEL_NOTE, WARN_LEVEL_WARN, WARN_LEVEL_ERROR, WARN_LEVEL_END}; uint code; enum_warning_level level; char *msg; MYSQL_ERROR(THD *thd, uint code_arg, enum_warning_level level_arg, const char *msg_arg) :code(code_arg), level(level_arg) { if (msg_arg) set_msg(thd, msg_arg); } void set_msg(THD *thd, const char *msg_arg); }; class delayed_insert; class select_result; #define THD_SENTRY_MAGIC 0xfeedd1ff #define THD_SENTRY_GONE 0xdeadbeef #define THD_CHECK_SENTRY(thd) DBUG_ASSERT(thd->dbug_sentry == THD_SENTRY_MAGIC) struct system_variables { ulonglong myisam_max_extra_sort_file_size; ulonglong myisam_max_sort_file_size; ha_rows select_limit; ha_rows max_join_size; ulong auto_increment_increment, auto_increment_offset; ulong bulk_insert_buff_size; ulong join_buff_size; ulong long_query_time; ulong max_allowed_packet; ulong max_error_count; ulong max_heap_table_size; ulong max_length_for_sort_data; ulong max_sort_length; ulong max_tmp_tables; ulong max_insert_delayed_threads; ulong myisam_repair_threads; ulong myisam_sort_buff_size; ulong net_buffer_length; ulong net_interactive_timeout; ulong net_read_timeout; ulong net_retry_count; ulong net_wait_timeout; ulong net_write_timeout; ulong optimizer_prune_level; ulong optimizer_search_depth; ulong preload_buff_size; ulong query_cache_type; ulong read_buff_size; ulong read_rnd_buff_size; ulong sortbuff_size; ulong table_type; ulong tmp_table_size; ulong tx_isolation; /* Determines which non-standard SQL behaviour should be enabled */ ulong sql_mode; /* check of key presence in updatable view */ ulong updatable_views_with_limit; ulong default_week_format; ulong max_seeks_for_key; ulong range_alloc_block_size; ulong query_alloc_block_size; ulong query_prealloc_size; ulong trans_alloc_block_size; ulong trans_prealloc_size; ulong log_warnings; ulong group_concat_max_len; /* In slave thread we need to know in behalf of which thread the query is being run to replicate temp tables properly */ ulong pseudo_thread_id; my_bool low_priority_updates; my_bool new_mode; my_bool query_cache_wlock_invalidate; my_bool old_passwords; /* Only charset part of these variables is sensible */ CHARSET_INFO *character_set_client; CHARSET_INFO *character_set_results; /* Both charset and collation parts of these variables are important */ CHARSET_INFO *collation_server; CHARSET_INFO *collation_database; CHARSET_INFO *collation_connection; Time_zone *time_zone; /* DATE, DATETIME and TIME formats */ DATE_TIME_FORMAT *date_format; DATE_TIME_FORMAT *datetime_format; DATE_TIME_FORMAT *time_format; }; /* per thread status variables */ typedef struct system_status_var { ulong bytes_received; ulong bytes_sent; ulong com_other; ulong com_stat[(uint) SQLCOM_END]; ulong created_tmp_disk_tables; ulong created_tmp_tables; ulong ha_commit_count; ulong ha_delete_count; ulong ha_read_first_count; ulong ha_read_last_count; ulong ha_read_key_count; ulong ha_read_next_count; ulong ha_read_prev_count; ulong ha_read_rnd_count; ulong ha_read_rnd_next_count; ulong ha_rollback_count; ulong ha_update_count; ulong ha_write_count; /* KEY_CACHE parts. These are copies of the original */ ulong key_blocks_changed; ulong key_blocks_used; ulong key_cache_r_requests; ulong key_cache_read; ulong key_cache_w_requests; ulong key_cache_write; /* END OF KEY_CACHE parts */ ulong net_big_packet_count; ulong opened_tables; ulong select_full_join_count; ulong select_full_range_join_count; ulong select_range_count; ulong select_range_check_count; ulong select_scan_count; ulong long_query_count; ulong filesort_merge_passes; ulong filesort_range_count; ulong filesort_rows; ulong filesort_scan_count; } STATUS_VAR; /* This is used for 'show status'. It must be updated to the last ulong variable in system_status_var */ #define last_system_status_var filesort_scan_count void free_tmp_table(THD *thd, TABLE *entry); class Item_arena { public: /* List of items created in the parser for this query. Every item puts itself to the list on creation (see Item::Item() for details)) */ Item *free_list; MEM_ROOT mem_root; enum enum_state { INITIALIZED= 0, PREPARED= 1, EXECUTED= 3, CONVENTIONAL_EXECUTION= 2, ERROR= -1 }; enum_state state; /* We build without RTTI, so dynamic_cast can't be used. */ enum Type { STATEMENT, PREPARED_STATEMENT, STORED_PROCEDURE }; Item_arena(THD *thd); Item_arena(); Item_arena(bool init_mem_root); virtual Type type() const; virtual ~Item_arena(); inline bool is_stmt_prepare() const { return (int)state < (int)PREPARED; } inline bool is_first_stmt_execute() const { return state == PREPARED; } inline bool is_conventional() const { return state == CONVENTIONAL_EXECUTION; } inline gptr alloc(unsigned int size) { return alloc_root(&mem_root,size); } inline gptr calloc(unsigned int size) { gptr ptr; if ((ptr=alloc_root(&mem_root,size))) bzero((char*) ptr,size); return ptr; } inline char *strdup(const char *str) { return strdup_root(&mem_root,str); } inline char *strmake(const char *str, uint size) { return strmake_root(&mem_root,str,size); } inline char *memdup(const char *str, uint size) { return memdup_root(&mem_root,str,size); } inline char *memdup_w_gap(const char *str, uint size, uint gap) { gptr ptr; if ((ptr=alloc_root(&mem_root,size+gap))) memcpy(ptr,str,size); return ptr; } void set_n_backup_item_arena(Item_arena *set, Item_arena *backup); void restore_backup_item_arena(Item_arena *set, Item_arena *backup); void set_item_arena(Item_arena *set); }; class Cursor; /* State of a single command executed against this connection. One connection can contain a lot of simultaneously running statements, some of which could be: - prepared, that is, contain placeholders, - opened as cursors. We maintain 1 to 1 relationship between statement and cursor - if user wants to create another cursor for his query, we create another statement for it. To perform some action with statement we reset THD part to the state of that statement, do the action, and then save back modified state from THD to the statement. It will be changed in near future, and Statement will be used explicitly. */ class Statement: public Item_arena { Statement(const Statement &rhs); /* not implemented: */ Statement &operator=(const Statement &rhs); /* non-copyable */ public: /* FIXME: must be private */ LEX main_lex; /* Uniquely identifies each statement object in thread scope; change during statement lifetime. FIXME: must be const */ ulong id; /* - if set_query_id=1, we set field->query_id for all fields. In that case field list can not contain duplicates. */ bool set_query_id; /* This variable is used in post-parse stage to declare that sum-functions, or functions which have sense only if GROUP BY is present, are allowed. For example in queries SELECT MIN(i) FROM foo SELECT GROUP_CONCAT(a, b, MIN(i)) FROM ... GROUP BY ... MIN(i) have no sense. Though it's grammar-related issue, it's hard to catch it out during the parse stage because GROUP BY clause goes in the end of query. This variable is mainly used in setup_fields/fix_fields. See item_sum.cc for details. */ bool allow_sum_func; LEX_STRING name; /* name for named prepared statements */ LEX *lex; // parse tree descriptor /* Points to the query associated with this statement. It's const, but we need to declare it char * because all table handlers are written in C and need to point to it. */ char *query; uint32 query_length; // current query length Cursor *cursor; public: /* This constructor is called when statement is a subobject of THD: some variables are initialized in THD::init due to locking problems */ Statement(); Statement(THD *thd); virtual ~Statement(); /* Assign execution context (note: not all members) of given stmt to self */ void set_statement(Statement *stmt); void set_n_backup_statement(Statement *stmt, Statement *backup); void restore_backup_statement(Statement *stmt, Statement *backup); /* return class type */ virtual Type type() const; /* Cleanup statement parse state (parse tree, lex) after execution of a non-prepared SQL statement. */ void end_statement(); }; /* Container for all statements created/used in a connection. Statements in Statement_map have unique Statement::id (guaranteed by id assignment in Statement::Statement) Non-empty statement names are unique too: attempt to insert a new statement with duplicate name causes older statement to be deleted Statements are auto-deleted when they are removed from the map and when the map is deleted. */ class Statement_map { public: Statement_map(); int insert(Statement *statement); Statement *find_by_name(LEX_STRING *name) { Statement *stmt; stmt= (Statement*)hash_search(&names_hash, (byte*)name->str, name->length); return stmt; } Statement *find(ulong id) { if (last_found_statement == 0 || id != last_found_statement->id) { Statement *stmt; stmt= (Statement *) hash_search(&st_hash, (byte *) &id, sizeof(id)); if (stmt && stmt->name.str) return NULL; last_found_statement= stmt; } return last_found_statement; } void erase(Statement *statement) { if (statement == last_found_statement) last_found_statement= 0; if (statement->name.str) { hash_delete(&names_hash, (byte *) statement); } hash_delete(&st_hash, (byte *) statement); } ~Statement_map() { hash_free(&st_hash); hash_free(&names_hash); } private: HASH st_hash; HASH names_hash; Statement *last_found_statement; }; /* For each client connection we create a separate thread with THD serving as a thread/connection descriptor */ class THD :public ilink, public Statement { public: #ifdef EMBEDDED_LIBRARY struct st_mysql *mysql; struct st_mysql_data *data; unsigned long client_stmt_id; unsigned long client_param_count; struct st_mysql_bind *client_params; char *extra_data; ulong extra_length; String query_rest; #endif NET net; // client connection descriptor MEM_ROOT warn_root; // For warnings and errors Protocol *protocol; // Current protocol Protocol_simple protocol_simple; // Normal protocol Protocol_prep protocol_prep; // Binary protocol HASH user_vars; // hash for user variables String packet; // dynamic buffer for network I/O String convert_buffer; // buffer for charset conversions struct sockaddr_in remote; // client socket address struct rand_struct rand; // used for authentication struct system_variables variables; // Changeable local variables struct system_status_var status_var; // Per thread statistic vars pthread_mutex_t LOCK_delete; // Locked before thd is deleted /* Note that (A) if we set query = NULL, we must at the same time set query_length = 0, and protect the whole operation with the LOCK_thread_count mutex. And (B) we are ONLY allowed to set query to a non-NULL value if its previous value is NULL. We do not need to protect operation (B) with any mutex. To avoid crashes in races, if we do not know that thd->query cannot change at the moment, one should print thd->query like this: (1) reserve the LOCK_thread_count mutex; (2) check if thd->query is NULL; (3) if not NULL, then print at most thd->query_length characters from it. We will see the query_length field as either 0, or the right value for it. Assuming that the write and read of an n-bit memory field in an n-bit computer is atomic, we can avoid races in the above way. This printing is needed at least in SHOW PROCESSLIST and SHOW INNODB STATUS. */ /* all prepared statements and cursors of this connection */ Statement_map stmt_map; /* keeps THD state while it is used for active statement Note: we perform special cleanup for it in THD destructor. */ Statement stmt_backup; /* A pointer to the stack frame of handle_one_connection(), which is called first in the thread for handling a client */ char *thread_stack; /* host - host of the client user - user of the client, set to NULL until the user has been read from the connection priv_user - The user privilege we are using. May be '' for anonymous user. db - currently selected database catalog - currently selected catalog ip - client IP WARNING: some members of THD (currently 'db', 'catalog' and 'query') are set and alloced by the slave SQL thread (for the THD of that thread); that thread is (and must remain, for now) the only responsible for freeing these 3 members. If you add members here, and you add code to set them in replication, don't forget to free_them_and_set_them_to_0 in replication properly. For details see the 'err:' label of the pthread_handler_decl of the slave SQL thread, in sql/slave.cc. */ char *host,*user,*priv_user,*db,*catalog,*ip; char priv_host[MAX_HOSTNAME]; /* remote (peer) port */ uint16 peer_port; /* Points to info-string that we show in SHOW PROCESSLIST You are supposed to update thd->proc_info only if you have coded a time-consuming piece that MySQL can get stuck in for a long time. */ const char *proc_info; /* points to host if host is available, otherwise points to ip */ const char *host_or_ip; ulong client_capabilities; /* What the client supports */ ulong max_client_packet_length; ulong master_access; /* Global privileges from mysql.user */ ulong db_access; /* Privileges for current db */ /* open_tables - list of regular tables in use by this thread temporary_tables - list of temp tables in use by this thread handler_tables - list of tables that were opened with HANDLER OPEN and are still in use by this thread */ TABLE *open_tables,*temporary_tables, *handler_tables, *derived_tables; /* During a MySQL session, one can lock tables in two modes: automatic or manual. In automatic mode all necessary tables are locked just before statement execution, and all acquired locks are stored in 'lock' member. Unlocking takes place automatically as well, when the statement ends. Manual mode comes into play when a user issues a 'LOCK TABLES' statement. In this mode the user can only use the locked tables. Trying to use any other tables will give an error. The locked tables are stored in 'locked_tables' member. Manual locking is described in the 'LOCK_TABLES' chapter of the MySQL manual. See also lock_tables() for details. */ MYSQL_LOCK *lock; /* Current locks */ MYSQL_LOCK *locked_tables; /* Tables locked with LOCK */ /* One thread can hold up to one named user-level lock. This variable points to a lock object if the lock is present. See item_func.cc and chapter 'Miscellaneous functions', for functions GET_LOCK, RELEASE_LOCK. */ User_level_lock *ull; #ifndef DBUG_OFF uint dbug_sentry; // watch out for memory corruption #endif struct st_my_thread_var *mysys_var; /* Type of current query: COM_PREPARE, COM_QUERY, etc. Set from first byte of the packet in do_command() */ enum enum_server_command command; uint32 server_id; uint32 file_id; // for LOAD DATA INFILE /* Used in error messages to tell user in what part of MySQL we found an error. E. g. when where= "having clause", if fix_fields() fails, user will know that the error was in having clause. */ const char *where; time_t start_time,time_after_lock,user_time; time_t connect_time,thr_create_time; // track down slow pthread_create thr_lock_type update_lock_default; delayed_insert *di; my_bool tablespace_op; /* This is TRUE in DISCARD/IMPORT TABLESPACE */ struct st_transactions { IO_CACHE trans_log; // Inited ONLY if binlog is open ! THD_TRANS all; // Trans since BEGIN WORK THD_TRANS stmt; // Trans for current statement uint bdb_lock_count; uint ndb_lock_count; #ifdef HAVE_NDBCLUSTER_DB void* ndb; #endif /* Tables changed in transaction (that must be invalidated in query cache). List contain only transactional tables, that not invalidated in query cache (instead of full list of changed in transaction tables). */ CHANGED_TABLE_LIST* changed_tables; MEM_ROOT mem_root; // Transaction-life memory allocation pool void cleanup() { changed_tables = 0; free_root(&mem_root,MYF(MY_KEEP_PREALLOC)); } } transaction; Field *dupp_field; #ifndef __WIN__ sigset_t signals,block_signals; #endif #ifdef SIGNAL_WITH_VIO_CLOSE Vio* active_vio; #endif /* Current prepared Item_arena if there one, or 0 */ Item_arena *current_arena; /* next_insert_id is set on SET INSERT_ID= #. This is used as the next generated auto_increment value in handler.cc */ ulonglong next_insert_id; /* Remember last next_insert_id to reset it if something went wrong */ ulonglong prev_insert_id; /* The insert_id used for the last statement or set by SET LAST_INSERT_ID=# or SELECT LAST_INSERT_ID(#). Used for binary log and returned by LAST_INSERT_ID() */ ulonglong last_insert_id; /* Set to the first value that LAST_INSERT_ID() returned for the last statement. When this is set, last_insert_id_used is set to true. */ ulonglong current_insert_id; ulonglong limit_found_rows; ha_rows cuted_fields, sent_row_count, examined_row_count; table_map used_tables; USER_CONN *user_connect; CHARSET_INFO *db_charset; List<TABLE> temporary_tables_should_be_free; // list of temporary tables /* FIXME: this, and some other variables like 'count_cuted_fields' maybe should be statement/cursor local, that is, moved to Statement class. With current implementation warnings produced in each prepared statement/cursor settle here. */ List <MYSQL_ERROR> warn_list; uint warn_count[(uint) MYSQL_ERROR::WARN_LEVEL_END]; uint total_warn_count; /* Id of current query. Statement can be reused to execute several queries query_id is global in context of the whole MySQL server. ID is automatically generated from mutex-protected counter. It's used in handler code for various purposes: to check which columns from table are necessary for this select, to check if it's necessary to update auto-updatable fields (like auto_increment and timestamp). */ ulong query_id; ulong warn_id, version, options, thread_id, col_access; /* Statement id is thread-wide. This counter is used to generate ids */ ulong statement_id_counter; ulong rand_saved_seed1, rand_saved_seed2; ulong row_count; // Row counter, mainly for errors and warnings long dbug_thread_id; pthread_t real_id; uint current_tablenr,tmp_table,global_read_lock; uint server_status,open_options,system_thread; uint32 db_length; uint select_number; //number of select (used for EXPLAIN) /* variables.transaction_isolation is reset to this after each commit */ enum_tx_isolation session_tx_isolation; enum_check_fields count_cuted_fields; /* for user variables replication*/ DYNAMIC_ARRAY user_var_events; enum killed_state { NOT_KILLED=0, KILL_BAD_DATA=1, KILL_CONNECTION=ER_SERVER_SHUTDOWN, KILL_QUERY=ER_QUERY_INTERRUPTED }; killed_state volatile killed; /* scramble - random string sent to client on handshake */ char scramble[SCRAMBLE_LENGTH+1]; bool slave_thread, one_shot_set; bool locked, some_tables_deleted; bool last_cuted_field; bool no_errors, password, is_fatal_error; bool query_start_used, rand_used, time_zone_used; bool last_insert_id_used,insert_id_used, clear_next_insert_id; bool in_lock_tables; bool query_error, bootstrap, cleanup_done; bool tmp_table_used; bool charset_is_system_charset, charset_is_collation_connection; bool slow_command; bool no_trans_update, abort_on_warning; longlong row_count_func; /* For the ROW_COUNT() function */ sp_rcontext *spcont; // SP runtime context sp_cache *sp_proc_cache; sp_cache *sp_func_cache; /* If we do a purge of binary logs, log index info of the threads that are currently reading it needs to be adjusted. To do that each thread that is using LOG_INFO needs to adjust the pointer to it */ LOG_INFO* current_linfo; NET* slave_net; // network connection from slave -> m. /* Used by the sys_var class to store temporary values */ union { my_bool my_bool_value; long long_value; } sys_var_tmp; THD(); ~THD(); void init(void); /* Initialize memory roots necessary for query processing and (!) pre-allocate memory for it. We can't do that in THD constructor because there are use cases (acl_init, delayed inserts, watcher threads, killing mysqld) where it's vital to not allocate excessive and not used memory. Note, that we still don't return error from init_for_queries(): if preallocation fails, we should notice that at the first call to alloc_root. */ void init_for_queries(); void change_user(void); void cleanup(void); void cleanup_after_query(); bool store_globals(); #ifdef SIGNAL_WITH_VIO_CLOSE inline void set_active_vio(Vio* vio) { pthread_mutex_lock(&LOCK_delete); active_vio = vio; pthread_mutex_unlock(&LOCK_delete); } inline void clear_active_vio() { pthread_mutex_lock(&LOCK_delete); active_vio = 0; pthread_mutex_unlock(&LOCK_delete); } void close_active_vio(); #endif void awake(THD::killed_state state_to_set); /* For enter_cond() / exit_cond() to work the mutex must be got before enter_cond() (in 4.1 an assertion will soon ensure this); this mutex is then released by exit_cond(). Use must be: lock mutex; enter_cond(); your code; exit_cond(). */ inline const char* enter_cond(pthread_cond_t *cond, pthread_mutex_t* mutex, const char* msg) { const char* old_msg = proc_info; mysys_var->current_mutex = mutex; mysys_var->current_cond = cond; proc_info = msg; return old_msg; } inline void exit_cond(const char* old_msg) { /* Putting the mutex unlock in exit_cond() ensures that mysys_var->current_mutex is always unlocked _before_ mysys_var->mutex is locked (if that would not be the case, you'll get a deadlock if someone does a THD::awake() on you). */ pthread_mutex_unlock(mysys_var->current_mutex); pthread_mutex_lock(&mysys_var->mutex); mysys_var->current_mutex = 0; mysys_var->current_cond = 0; proc_info = old_msg; pthread_mutex_unlock(&mysys_var->mutex); } inline time_t query_start() { query_start_used=1; return start_time; } inline void set_time() { if (user_time) start_time=time_after_lock=user_time; else time_after_lock=time(&start_time); } inline void end_time() { time(&start_time); } inline void set_time(time_t t) { time_after_lock=start_time=user_time=t; } inline void lock_time() { time(&time_after_lock); } inline void insert_id(ulonglong id_arg) { last_insert_id= id_arg; insert_id_used=1; } inline ulonglong insert_id(void) { if (!last_insert_id_used) { last_insert_id_used=1; current_insert_id=last_insert_id; } return last_insert_id; } inline ulonglong found_rows(void) { return limit_found_rows; } inline bool active_transaction() { #ifdef USING_TRANSACTIONS return (transaction.all.bdb_tid != 0 || transaction.all.innodb_active_trans != 0 || transaction.all.ndb_tid != 0); #else return 0; #endif } inline bool only_prepare() { return command == COM_PREPARE; } inline gptr trans_alloc(unsigned int size) { return alloc_root(&transaction.mem_root,size); } bool convert_string(LEX_STRING *to, CHARSET_INFO *to_cs, const char *from, uint from_length, CHARSET_INFO *from_cs); bool convert_string(String *s, CHARSET_INFO *from_cs, CHARSET_INFO *to_cs); void add_changed_table(TABLE *table); void add_changed_table(const char *key, long key_length); CHANGED_TABLE_LIST * changed_table_dup(const char *key, long key_length); int send_explain_fields(select_result *result); #ifndef EMBEDDED_LIBRARY inline void clear_error() { net.last_error[0]= 0; net.last_errno= 0; net.report_error= 0; query_error= 0; } inline bool vio_ok() const { return net.vio != 0; } #else void clear_error(); inline bool vio_ok() const { return true; } #endif inline void fatal_error() { is_fatal_error= 1; net.report_error= 1; DBUG_PRINT("error",("Fatal error set")); } inline CHARSET_INFO *charset() { return variables.character_set_client; } void update_charset(); inline int killed_errno() const { return killed != KILL_BAD_DATA ? killed : 0; } inline void send_kill_message() const { my_error(killed_errno(), MYF(0)); } /* return TRUE if we will abort query if we make a warning now */ inline bool really_abort_on_warning() { return (abort_on_warning && (!no_trans_update || (variables.sql_mode & MODE_STRICT_ALL_TABLES))); } void set_status_var_init(); }; /* Flags for the THD::system_thread (bitmap) variable */ #define SYSTEM_THREAD_DELAYED_INSERT 1 #define SYSTEM_THREAD_SLAVE_IO 2 #define SYSTEM_THREAD_SLAVE_SQL 4 /* Disables binary logging for one thread, and resets it back to what it was before being disabled. Some functions (like the internal mysql_create_table() when it's called by mysql_alter_table()) must NOT write to the binlog (binlogging is done at the at a later stage of the command already, and must be, for locking reasons); so we internally disable it temporarily by creating the Disable_binlog object and reset the state by destroying the object (don't forget that! or write code so that the object gets automatically destroyed when leaving a block, see example in sql_table.cc). */ class Disable_binlog { private: THD *thd; ulong save_options; public: Disable_binlog(THD *thd_arg); ~Disable_binlog(); }; /* Used to hold information about file and file structure in exchainge via non-DB file (...INTO OUTFILE..., ...LOAD DATA...) XXX: We never call destructor for objects of this class. */ class sql_exchange :public Sql_alloc { public: char *file_name; String *field_term,*enclosed,*line_term,*line_start,*escaped; bool opt_enclosed; bool dumpfile; ulong skip_lines; sql_exchange(char *name,bool dumpfile_flag); }; #include "log_event.h" /* This is used to get result from a select */ class JOIN; class select_result :public Sql_alloc { protected: THD *thd; SELECT_LEX_UNIT *unit; public: select_result(); virtual ~select_result() {}; virtual int prepare(List<Item> &list, SELECT_LEX_UNIT *u) { unit= u; return 0; } virtual bool send_fields(List<Item> &list, uint flags)=0; virtual bool send_data(List<Item> &items)=0; virtual bool initialize_tables (JOIN *join=0) { return 0; } virtual void send_error(uint errcode,const char *err); virtual bool send_eof()=0; virtual void abort() {} /* Cleanup instance of this class for next execution of a prepared statement/stored procedure. */ virtual void cleanup(); }; class select_send :public select_result { public: select_send() {} bool send_fields(List<Item> &list, uint flags); bool send_data(List<Item> &items); bool send_eof(); }; class select_to_file :public select_result { protected: sql_exchange *exchange; File file; IO_CACHE cache; ha_rows row_count; char path[FN_REFLEN]; public: select_to_file(sql_exchange *ex) :exchange(ex), file(-1),row_count(0L) { path[0]=0; } ~select_to_file(); bool send_fields(List<Item> &list, uint flags) { return 0; } void send_error(uint errcode,const char *err); bool send_eof(); void cleanup(); }; class select_export :public select_to_file { uint field_term_length; int field_sep_char,escape_char,line_sep_char; bool fixed_row_size; public: select_export(sql_exchange *ex) :select_to_file(ex) {} ~select_export(); int prepare(List<Item> &list, SELECT_LEX_UNIT *u); bool send_data(List<Item> &items); }; class select_dump :public select_to_file { public: select_dump(sql_exchange *ex) :select_to_file(ex) {} int prepare(List<Item> &list, SELECT_LEX_UNIT *u); bool send_data(List<Item> &items); }; class select_insert :public select_result { public: TABLE_LIST *table_list; TABLE *table; List<Item> *fields; ulonglong last_insert_id; COPY_INFO info; bool insert_into_view; select_insert(TABLE_LIST *table_list_par, TABLE *table_par, List<Item> *fields_par, enum_duplicates duplic, bool ignore_check_option_errors); ~select_insert(); int prepare(List<Item> &list, SELECT_LEX_UNIT *u); bool send_fields(List<Item> &list, uint flags) { return 0; } bool send_data(List<Item> &items); void send_error(uint errcode,const char *err); bool send_eof(); /* not implemented: select_insert is never re-used in prepared statements */ void cleanup(); }; class select_create: public select_insert { ORDER *group; TABLE_LIST *create_table; List<create_field> *extra_fields; List<Key> *keys; HA_CREATE_INFO *create_info; MYSQL_LOCK *lock; Field **field; public: select_create (TABLE_LIST *table, HA_CREATE_INFO *create_info_par, List<create_field> &fields_par, List<Key> &keys_par, List<Item> &select_fields,enum_duplicates duplic) :select_insert (NULL, NULL, &select_fields, duplic, 0), create_table(table), extra_fields(&fields_par),keys(&keys_par), create_info(create_info_par), lock(0) {} int prepare(List<Item> &list, SELECT_LEX_UNIT *u); bool send_data(List<Item> &values); bool send_eof(); void abort(); }; #include <myisam.h> /* Param to create temporary tables when doing SELECT:s */ class TMP_TABLE_PARAM :public Sql_alloc { private: /* Prevent use of these (not safe because of lists and copy_field) */ TMP_TABLE_PARAM(const TMP_TABLE_PARAM &); void operator=(TMP_TABLE_PARAM &); public: List<Item> copy_funcs; List<Item> save_copy_funcs; List_iterator_fast<Item> copy_funcs_it; Copy_field *copy_field, *copy_field_end; Copy_field *save_copy_field, *save_copy_field_end; byte *group_buff; Item **items_to_copy; /* Fields in tmp table */ MI_COLUMNDEF *recinfo,*start_recinfo; KEY *keyinfo; ha_rows end_write_records; uint field_count,sum_func_count,func_count; uint hidden_field_count; uint group_parts,group_length,group_null_parts; uint quick_group; bool using_indirect_summary_function; TMP_TABLE_PARAM() :copy_funcs_it(copy_funcs), copy_field(0), group_parts(0), group_length(0), group_null_parts(0) {} ~TMP_TABLE_PARAM() { cleanup(); } void init(void); inline void cleanup(void) { if (copy_field) /* Fix for Intel compiler */ { delete [] copy_field; copy_field=0; } } }; class select_union :public select_result { public: TABLE *table; COPY_INFO info; TMP_TABLE_PARAM tmp_table_param; select_union(TABLE *table_par); ~select_union(); int prepare(List<Item> &list, SELECT_LEX_UNIT *u); bool send_fields(List<Item> &list, uint flags) { return 0; } bool send_data(List<Item> &items); bool send_eof(); bool flush(); void set_table(TABLE *tbl) { table= tbl; } }; /* Base subselect interface class */ class select_subselect :public select_result { protected: Item_subselect *item; public: select_subselect(Item_subselect *item); bool send_fields(List<Item> &list, uint flags) { return 0; } bool send_data(List<Item> &items)=0; bool send_eof() { return 0; }; friend class Ttem_subselect; }; /* Single value subselect interface class */ class select_singlerow_subselect :public select_subselect { public: select_singlerow_subselect(Item_subselect *item):select_subselect(item){} bool send_data(List<Item> &items); }; /* used in independent ALL/ANY optimisation */ class select_max_min_finder_subselect :public select_subselect { Item_cache *cache; bool (select_max_min_finder_subselect::*op)(); bool fmax; public: select_max_min_finder_subselect(Item_subselect *item, bool mx) :select_subselect(item), cache(0), fmax(mx) {} bool send_data(List<Item> &items); bool cmp_real(); bool cmp_int(); bool cmp_str(); }; /* EXISTS subselect interface class */ class select_exists_subselect :public select_subselect { public: select_exists_subselect(Item_subselect *item):select_subselect(item){} bool send_data(List<Item> &items); }; /* Structs used when sorting */ typedef struct st_sort_field { Field *field; /* Field to sort */ Item *item; /* Item if not sorting fields */ uint length; /* Length of sort field */ Item_result result_type; /* Type of item */ bool reverse; /* if descending sort */ bool need_strxnfrm; /* If we have to use strxnfrm() */ } SORT_FIELD; typedef struct st_sort_buffer { uint index; /* 0 or 1 */ uint sort_orders; uint change_pos; /* If sort-fields changed */ char **buff; SORT_FIELD *sortorder; } SORT_BUFFER; /* Structure for db & table in sql_yacc */ class Table_ident :public Sql_alloc { public: LEX_STRING db; LEX_STRING table; SELECT_LEX_UNIT *sel; inline Table_ident(THD *thd, LEX_STRING db_arg, LEX_STRING table_arg, bool force) :table(table_arg), sel((SELECT_LEX_UNIT *)0) { if (!force && (thd->client_capabilities & CLIENT_NO_SCHEMA)) db.str=0; else db= db_arg; } inline Table_ident(LEX_STRING table_arg) :table(table_arg), sel((SELECT_LEX_UNIT *)0) { db.str=0; } inline Table_ident(SELECT_LEX_UNIT *s) : sel(s) { /* We must have a table name here as this is used with add_table_to_list */ db.str=0; table.str= internal_table_name; table.length=1; } inline void change_db(char *db_name) { db.str= db_name; db.length= (uint) strlen(db_name); } }; // this is needed for user_vars hash class user_var_entry { public: LEX_STRING name; char *value; ulong length, update_query_id, used_query_id; Item_result type; double val(my_bool *null_value); longlong val_int(my_bool *null_value); String *val_str(my_bool *null_value, String *str, uint decimals); DTCollation collation; }; /* Unique -- class for unique (removing of duplicates). Puts all values to the TREE. If the tree becomes too big, it's dumped to the file. User can request sorted values, or just iterate through them. In the last case tree merging is performed in memory simultaneously with iteration, so it should be ~2-3x faster. */ class Unique :public Sql_alloc { DYNAMIC_ARRAY file_ptrs; ulong max_elements, max_in_memory_size; IO_CACHE file; TREE tree; byte *record_pointers; bool flush(); uint size; public: ulong elements; Unique(qsort_cmp2 comp_func, void *comp_func_fixed_arg, uint size_arg, ulong max_in_memory_size_arg); ~Unique(); inline bool unique_add(void *ptr) { if (tree.elements_in_tree > max_elements && flush()) return 1; return !tree_insert(&tree, ptr, 0, tree.custom_arg); } bool get(TABLE *table); static double get_use_cost(uint *buffer, uint nkeys, uint key_size, ulong max_in_memory_size); inline static int get_cost_calc_buff_size(ulong nkeys, uint key_size, ulong max_in_memory_size) { register ulong max_elems_in_tree= (1 + max_in_memory_size / ALIGN_SIZE(sizeof(TREE_ELEMENT)+key_size)); return sizeof(uint)*(1 + nkeys/max_elems_in_tree); } void reset(); bool walk(tree_walk_action action, void *walk_action_arg); friend int unique_write_to_file(gptr key, element_count count, Unique *unique); friend int unique_write_to_ptrs(gptr key, element_count count, Unique *unique); }; class multi_delete :public select_result { TABLE_LIST *delete_tables, *table_being_deleted; Unique **tempfiles; THD *thd; ha_rows deleted, found; uint num_of_tables; int error; bool do_delete, transactional_tables, log_delayed, normal_tables; public: multi_delete(THD *thd, TABLE_LIST *dt, uint num_of_tables); ~multi_delete(); int prepare(List<Item> &list, SELECT_LEX_UNIT *u); bool send_fields(List<Item> &list, uint flags) { return 0; } bool send_data(List<Item> &items); bool initialize_tables (JOIN *join); void send_error(uint errcode,const char *err); int do_deletes (bool from_send_error); bool send_eof(); }; class multi_update :public select_result { TABLE_LIST *all_tables, *update_tables, *table_being_updated; THD *thd; TABLE **tmp_tables, *main_table, *table_to_update; TMP_TABLE_PARAM *tmp_table_param; ha_rows updated, found; List <Item> *fields, *values; List <Item> **fields_for_table, **values_for_table; uint table_count; Copy_field *copy_field; enum enum_duplicates handle_duplicates; bool do_update, trans_safe, transactional_tables, log_delayed; public: multi_update(THD *thd_arg, TABLE_LIST *ut, List<Item> *fields, List<Item> *values, enum_duplicates handle_duplicates); ~multi_update(); int prepare(List<Item> &list, SELECT_LEX_UNIT *u); bool send_fields(List<Item> &list, uint flags) { return 0; } bool send_data(List<Item> &items); bool initialize_tables (JOIN *join); void send_error(uint errcode,const char *err); int do_updates (bool from_send_error); bool send_eof(); }; class my_var : public Sql_alloc { public: LEX_STRING s; bool local; uint offset; enum_field_types type; my_var (LEX_STRING& j, bool i, uint o, enum_field_types t) :s(j), local(i), offset(o), type(t) {} ~my_var() {} }; class select_dumpvar :public select_result { ha_rows row_count; public: List<my_var> var_list; List<Item_func_set_user_var> vars; List<Item_splocal> local_vars; select_dumpvar(void) { var_list.empty(); local_vars.empty(); vars.empty(); row_count=0;} ~select_dumpvar() {} int prepare(List<Item> &list, SELECT_LEX_UNIT *u); bool send_fields(List<Item> &list, uint flags) { return 0; } bool send_data(List<Item> &items); bool send_eof(); void cleanup(); }; /* Functions in sql_class.cc */ void add_to_status(STATUS_VAR *to_var, STATUS_VAR *from_var);