1 /* Copyright (c) 2000, 2011, Oracle and/or its affiliates.
2    Copyright (c) 2010, 2017, MariaDB Corporation.
3 
4    This program is free software; you can redistribute it and/or modify
5    it under the terms of the GNU General Public License as published by
6    the Free Software Foundation; version 2 of the License.
7 
8    This program is distributed in the hope that it will be useful,
9    but WITHOUT ANY WARRANTY; without even the implied warranty of
10    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11    GNU General Public License for more details.
12 
13    You should have received a copy of the GNU General Public License
14    along with this program; if not, write to the Free Software
15    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335  USA */
16 
17 /*
18 ** Common definition between mysql server & client
19 */
20 
21 #ifndef _mysql_com_h
22 #define _mysql_com_h
23 
24 #include "my_decimal_limits.h"
25 
26 #define HOSTNAME_LENGTH 60
27 #define SYSTEM_CHARSET_MBMAXLEN 3
28 #define NAME_CHAR_LEN	64U             /* Field/table name length */
29 #define USERNAME_CHAR_LENGTH 128
30 #define NAME_LEN                (NAME_CHAR_LEN*SYSTEM_CHARSET_MBMAXLEN)
31 #define USERNAME_LENGTH         (USERNAME_CHAR_LENGTH*SYSTEM_CHARSET_MBMAXLEN)
32 #define DEFINER_CHAR_LENGTH     (USERNAME_CHAR_LENGTH + HOSTNAME_LENGTH + 1)
33 #define DEFINER_LENGTH          (USERNAME_LENGTH + HOSTNAME_LENGTH + 1)
34 
35 #define MYSQL_AUTODETECT_CHARSET_NAME "auto"
36 
37 #define MYSQL50_TABLE_NAME_PREFIX         "#mysql50#"
38 #define MYSQL50_TABLE_NAME_PREFIX_LENGTH  (sizeof(MYSQL50_TABLE_NAME_PREFIX)-1)
39 #define SAFE_NAME_LEN (NAME_LEN + MYSQL50_TABLE_NAME_PREFIX_LENGTH)
40 
41 /*
42   MDEV-4088
43 
44   MySQL (and MariaDB 5.x before the fix) was using the first character of the
45   server version string (as sent in the first handshake protocol packet) to
46   decide on the replication event formats. And for 10.x the first character
47   is "1", which the slave thought comes from some ancient 1.x version
48   (ignoring the fact that the first ever MySQL version was 3.x).
49 
50   To support replication to these old clients, we fake the version in the
51   first handshake protocol packet to start from "5.5.5-" (for example,
52   it might be "5.5.5-10.0.1-MariaDB-debug-log".
53 
54   On the client side we remove this fake version prefix to restore the
55   correct server version. The version "5.5.5" did not support
56   pluggable authentication, so any version starting from "5.5.5-" and
57   claiming to support pluggable auth, must be using this fake prefix.
58 */
59 /* this version must be the one that *does not* support pluggable auth */
60 #define RPL_VERSION_HACK "5.5.5-"
61 
62 #define SERVER_VERSION_LENGTH 60
63 #define SQLSTATE_LENGTH 5
64 #define LIST_PROCESS_HOST_LEN 64
65 
66 /*
67   Maximum length of comments
68 */
69 #define TABLE_COMMENT_INLINE_MAXLEN 180 /* pre 5.5: 60 characters */
70 #define TABLE_COMMENT_MAXLEN 2048
71 #define COLUMN_COMMENT_MAXLEN 1024
72 #define INDEX_COMMENT_MAXLEN 1024
73 #define TABLE_PARTITION_COMMENT_MAXLEN 1024
74 
75 /*
76   Maximum length of protocol packet.
77   OK packet length limit also restricted to this value as any length greater
78   than this value will have first byte of OK packet to be 254 thus does not
79   provide a means to identify if this is OK or EOF packet.
80 */
81 #define MAX_PACKET_LENGTH (256L*256L*256L-1)
82 
83 /*
84   USER_HOST_BUFF_SIZE -- length of string buffer, that is enough to contain
85   username and hostname parts of the user identifier with trailing zero in
86   MySQL standard format:
87   user_name_part@host_name_part\0
88 */
89 #define USER_HOST_BUFF_SIZE HOSTNAME_LENGTH + USERNAME_LENGTH + 2
90 
91 #define LOCAL_HOST	"localhost"
92 #define LOCAL_HOST_NAMEDPIPE "."
93 
94 
95 #if defined(__WIN__) && !defined( _CUSTOMCONFIG_)
96 #define MYSQL_NAMEDPIPE "MySQL"
97 #define MYSQL_SERVICENAME "MySQL"
98 #endif /* __WIN__ */
99 
100 /*
101   You should add new commands to the end of this list, otherwise old
102   servers won't be able to handle them as 'unsupported'.
103 */
104 
105 enum enum_server_command
106 {
107   COM_SLEEP, COM_QUIT, COM_INIT_DB, COM_QUERY, COM_FIELD_LIST,
108   COM_CREATE_DB, COM_DROP_DB, COM_REFRESH, COM_SHUTDOWN, COM_STATISTICS,
109   COM_PROCESS_INFO, COM_CONNECT, COM_PROCESS_KILL, COM_DEBUG, COM_PING,
110   COM_TIME, COM_DELAYED_INSERT, COM_CHANGE_USER, COM_BINLOG_DUMP,
111   COM_TABLE_DUMP, COM_CONNECT_OUT, COM_REGISTER_SLAVE,
112   COM_STMT_PREPARE, COM_STMT_EXECUTE, COM_STMT_SEND_LONG_DATA, COM_STMT_CLOSE,
113   COM_STMT_RESET, COM_SET_OPTION, COM_STMT_FETCH, COM_DAEMON,
114   COM_UNIMPLEMENTED, /* COM_BINLOG_DUMP_GTID in MySQL */
115   COM_RESET_CONNECTION,
116   /* don't forget to update const char *command_name[] in sql_parse.cc */
117   COM_MDB_GAP_BEG,
118   COM_MDB_GAP_END=249,
119   COM_STMT_BULK_EXECUTE=250,
120   COM_SLAVE_WORKER=251,
121   COM_SLAVE_IO=252,
122   COM_SLAVE_SQL=253,
123   COM_MULTI=254,
124   /* Must be last */
125   COM_END=255
126 };
127 
128 
129 /*
130   Bulk PS protocol indicator value:
131 */
132 enum enum_indicator_type
133 {
134   STMT_INDICATOR_NONE= 0,
135   STMT_INDICATOR_NULL,
136   STMT_INDICATOR_DEFAULT,
137   STMT_INDICATOR_IGNORE
138 };
139 
140 /*
141   bulk PS flags
142 */
143 #define STMT_BULK_FLAG_CLIENT_SEND_TYPES 128
144 #define STMT_BULK_FLAG_INSERT_ID_REQUEST 64
145 
146 
147 /* sql type stored in .frm files for virtual fields */
148 #define MYSQL_TYPE_VIRTUAL 245
149 /*
150   Length of random string sent by server on handshake; this is also length of
151   obfuscated password, received from client
152 */
153 #define SCRAMBLE_LENGTH 20
154 #define SCRAMBLE_LENGTH_323 8
155 /* length of password stored in the db: new passwords are preceded with '*' */
156 #define SCRAMBLED_PASSWORD_CHAR_LENGTH (SCRAMBLE_LENGTH*2+1)
157 #define SCRAMBLED_PASSWORD_CHAR_LENGTH_323 (SCRAMBLE_LENGTH_323*2)
158 
159 
160 #define NOT_NULL_FLAG	1U		/* Field can't be NULL */
161 #define PRI_KEY_FLAG	2U		/* Field is part of a primary key */
162 #define UNIQUE_KEY_FLAG 4U		/* Field is part of a unique key */
163 #define MULTIPLE_KEY_FLAG 8U		/* Field is part of a key */
164 #define BLOB_FLAG	16U		/* Field is a blob */
165 #define UNSIGNED_FLAG	32U		/* Field is unsigned */
166 #define ZEROFILL_FLAG	64U		/* Field is zerofill */
167 #define BINARY_FLAG	128U		/* Field is binary   */
168 
169 /* The following are only sent to new clients */
170 #define ENUM_FLAG	256U		/* field is an enum */
171 #define AUTO_INCREMENT_FLAG 512U	/* field is a autoincrement field */
172 #define TIMESTAMP_FLAG	1024U		/* Field is a timestamp */
173 #define SET_FLAG	2048U		/* field is a set */
174 #define NO_DEFAULT_VALUE_FLAG 4096U	/* Field doesn't have default value */
175 #define ON_UPDATE_NOW_FLAG 8192U	/* Field is set to NOW on UPDATE */
176 #define NUM_FLAG	32768U		/* Field is num (for clients) */
177 #define PART_KEY_FLAG	16384U		/* Intern; Part of some key */
178 #define GROUP_FLAG	32768U		/* Intern: Group field */
179 #define BINCMP_FLAG	131072U		/* Intern: Used by sql_yacc */
180 #define GET_FIXED_FIELDS_FLAG (1U << 18) /* Used to get fields in item tree */
181 #define FIELD_IN_PART_FUNC_FLAG (1U << 19)/* Field part of partition func */
182 #define PART_INDIRECT_KEY_FLAG (1U << 20)
183 
184 /**
185   Intern: Field in TABLE object for new version of altered table,
186           which participates in a newly added index.
187 */
188 #define FIELD_IN_ADD_INDEX (1U << 20)
189 #define FIELD_IS_RENAMED (1U << 21)     /* Intern: Field is being renamed */
190 #define FIELD_FLAGS_STORAGE_MEDIA 22    /* Field storage media, bit 22-23 */
191 #define FIELD_FLAGS_STORAGE_MEDIA_MASK (3U << FIELD_FLAGS_STORAGE_MEDIA)
192 #define FIELD_FLAGS_COLUMN_FORMAT 24    /* Field column format, bit 24-25 */
193 #define FIELD_FLAGS_COLUMN_FORMAT_MASK (3U << FIELD_FLAGS_COLUMN_FORMAT)
194 #define FIELD_IS_DROPPED (1U << 26)     /* Intern: Field is being dropped */
195 
196 #define VERS_ROW_START (1 << 27)   /* autogenerated column declared with
197                                              `generated always as row start`
198                                               (see II.a SQL Standard) */
199 #define VERS_ROW_END (1 << 28)     /* autogenerated column declared with
200                                            `generated always as row end`
201                                             (see II.a SQL Standard).*/
202 #define VERS_SYSTEM_FIELD (VERS_ROW_START | VERS_ROW_END)
203 #define VERS_UPDATE_UNVERSIONED_FLAG (1 << 29) /* column that doesn't support
204                                                 system versioning when table
205                                                 itself supports it*/
206 
207 #define REFRESH_GRANT           (1ULL << 0)  /* Refresh grant tables */
208 #define REFRESH_LOG             (1ULL << 1)  /* Start on new log file */
209 #define REFRESH_TABLES          (1ULL << 2)  /* close all tables */
210 #define REFRESH_HOSTS           (1ULL << 3)  /* Flush host cache */
211 #define REFRESH_STATUS          (1ULL << 4)  /* Flush status variables */
212 #define REFRESH_THREADS         (1ULL << 5)  /* Flush thread cache */
213 #define REFRESH_SLAVE           (1ULL << 6)  /* Reset master info and restart slave
214                                              thread */
215 #define REFRESH_MASTER          (1ULL << 7)  /* Remove all bin logs in the index
216                                              and truncate the index */
217 
218 /* The following can't be set with mysql_refresh() */
219 #define REFRESH_ERROR_LOG       (1ULL << 8)  /* Rotate only the error log */
220 #define REFRESH_ENGINE_LOG      (1ULL << 9)  /* Flush all storage engine logs */
221 #define REFRESH_BINARY_LOG      (1ULL << 10) /* Flush the binary log */
222 #define REFRESH_RELAY_LOG       (1ULL << 11) /* Flush the relay log */
223 #define REFRESH_GENERAL_LOG     (1ULL << 12) /* Flush the general log */
224 #define REFRESH_SLOW_LOG        (1ULL << 13) /* Flush the slow query log */
225 
226 #define REFRESH_READ_LOCK       (1ULL << 14) /* Lock tables for read */
227 #define REFRESH_CHECKPOINT      (1ULL << 15) /* With REFRESH_READ_LOCK: block checkpoints too */
228 
229 #define REFRESH_QUERY_CACHE     (1ULL << 16) /* clear the query cache */
230 #define REFRESH_QUERY_CACHE_FREE (1ULL << 17) /* pack query cache */
231 #define REFRESH_DES_KEY_FILE    (1ULL << 18)
232 #define REFRESH_USER_RESOURCES  (1ULL << 19)
233 #define REFRESH_FOR_EXPORT      (1ULL << 20) /* FLUSH TABLES ... FOR EXPORT */
234 
235 #define REFRESH_GENERIC         (1ULL << 30)
236 #define REFRESH_FAST            (1ULL << 31) /* Intern flag */
237 
238 #define CLIENT_LONG_PASSWORD	0	/* obsolete flag */
239 #define CLIENT_MYSQL            1ULL       /* mysql/old mariadb server/client */
240 #define CLIENT_FOUND_ROWS	2ULL	/* Found instead of affected rows */
241 #define CLIENT_LONG_FLAG	4ULL	/* Get all column flags */
242 #define CLIENT_CONNECT_WITH_DB	8ULL	/* One can specify db on connect */
243 #define CLIENT_NO_SCHEMA	16ULL	/* Don't allow database.table.column */
244 #define CLIENT_COMPRESS		32ULL	/* Can use compression protocol */
245 #define CLIENT_ODBC		64ULL	/* Odbc client */
246 #define CLIENT_LOCAL_FILES	128ULL	/* Can use LOAD DATA LOCAL */
247 #define CLIENT_IGNORE_SPACE	256ULL	/* Ignore spaces before '(' */
248 #define CLIENT_PROTOCOL_41	512ULL	/* New 4.1 protocol */
249 #define CLIENT_INTERACTIVE	1024ULL	/* This is an interactive client */
250 #define CLIENT_SSL              2048ULL	/* Switch to SSL after handshake */
251 #define CLIENT_IGNORE_SIGPIPE   4096ULL    /* IGNORE sigpipes */
252 #define CLIENT_TRANSACTIONS	8192ULL	/* Client knows about transactions */
253 #define CLIENT_RESERVED         16384ULL   /* Old flag for 4.1 protocol  */
254 #define CLIENT_SECURE_CONNECTION 32768ULL  /* New 4.1 authentication */
255 #define CLIENT_MULTI_STATEMENTS (1ULL << 16) /* Enable/disable multi-stmt support */
256 #define CLIENT_MULTI_RESULTS    (1ULL << 17) /* Enable/disable multi-results */
257 #define CLIENT_PS_MULTI_RESULTS (1ULL << 18) /* Multi-results in PS-protocol */
258 
259 #define CLIENT_PLUGIN_AUTH  (1ULL << 19) /* Client supports plugin authentication */
260 #define CLIENT_CONNECT_ATTRS (1ULL << 20) /* Client supports connection attributes */
261 /* Enable authentication response packet to be larger than 255 bytes. */
262 #define CLIENT_PLUGIN_AUTH_LENENC_CLIENT_DATA (1ULL << 21)
263 /* Don't close the connection for a connection with expired password. */
264 #define CLIENT_CAN_HANDLE_EXPIRED_PASSWORDS (1ULL << 22)
265 
266 /**
267   Capable of handling server state change information. Its a hint to the
268   server to include the state change information in Ok packet.
269 */
270 #define CLIENT_SESSION_TRACK (1ULL << 23)
271 /* Client no longer needs EOF packet */
272 #define CLIENT_DEPRECATE_EOF (1ULL << 24)
273 
274 #define CLIENT_PROGRESS_OBSOLETE  (1ULL << 29)
275 #define CLIENT_SSL_VERIFY_SERVER_CERT (1ULL << 30)
276 /*
277   It used to be that if mysql_real_connect() failed, it would delete any
278   options set by the client, unless the CLIENT_REMEMBER_OPTIONS flag was
279   given.
280   That behaviour does not appear very useful, and it seems unlikely that
281   any applications would actually depend on this. So from MariaDB 5.5 we
282   always preserve any options set in case of failed connect, and this
283   option is effectively always set.
284 */
285 #define CLIENT_REMEMBER_OPTIONS (1ULL << 31)
286 
287 /* MariaDB extended capability flags */
288 #define MARIADB_CLIENT_FLAGS_MASK 0xffffffff00000000ULL
289 /* Client support progress indicator */
290 #define MARIADB_CLIENT_PROGRESS (1ULL << 32)
291 /* support COM_MULTI */
292 #define MARIADB_CLIENT_COM_MULTI (1ULL << 33)
293 /* support of array binding */
294 #define MARIADB_CLIENT_STMT_BULK_OPERATIONS (1ULL << 34)
295 
296 #ifdef HAVE_COMPRESS
297 #define CAN_CLIENT_COMPRESS CLIENT_COMPRESS
298 #else
299 #define CAN_CLIENT_COMPRESS 0
300 #endif
301 
302 /*
303   Gather all possible capabilities (flags) supported by the server
304 
305   MARIADB_* flags supported only by MariaDB connector(s).
306 */
307 #define CLIENT_ALL_FLAGS  (\
308                            CLIENT_FOUND_ROWS | \
309                            CLIENT_LONG_FLAG | \
310                            CLIENT_CONNECT_WITH_DB | \
311                            CLIENT_NO_SCHEMA | \
312                            CLIENT_COMPRESS | \
313                            CLIENT_ODBC | \
314                            CLIENT_LOCAL_FILES | \
315                            CLIENT_IGNORE_SPACE | \
316                            CLIENT_PROTOCOL_41 | \
317                            CLIENT_INTERACTIVE | \
318                            CLIENT_SSL | \
319                            CLIENT_IGNORE_SIGPIPE | \
320                            CLIENT_TRANSACTIONS | \
321                            CLIENT_RESERVED | \
322                            CLIENT_SECURE_CONNECTION | \
323                            CLIENT_MULTI_STATEMENTS | \
324                            CLIENT_MULTI_RESULTS | \
325                            CLIENT_PS_MULTI_RESULTS | \
326                            CLIENT_SSL_VERIFY_SERVER_CERT | \
327                            CLIENT_REMEMBER_OPTIONS | \
328                            MARIADB_CLIENT_PROGRESS | \
329                            CLIENT_PLUGIN_AUTH | \
330                            CLIENT_PLUGIN_AUTH_LENENC_CLIENT_DATA | \
331                            CLIENT_SESSION_TRACK |\
332                            CLIENT_DEPRECATE_EOF |\
333                            CLIENT_CONNECT_ATTRS |\
334                            MARIADB_CLIENT_COM_MULTI |\
335                            MARIADB_CLIENT_STMT_BULK_OPERATIONS)
336 
337 /*
338   To be added later:
339   CLIENT_CAN_HANDLE_EXPIRED_PASSWORDS
340 */
341 
342 /*
343   Switch off the flags that are optional and depending on build flags
344   If any of the optional flags is supported by the build it will be switched
345   on before sending to the client during the connection handshake.
346 */
347 #define CLIENT_BASIC_FLAGS (((CLIENT_ALL_FLAGS & ~CLIENT_SSL) \
348                                                & ~CLIENT_COMPRESS) \
349                                                & ~CLIENT_SSL_VERIFY_SERVER_CERT)
350 
351 /**
352   Is raised when a multi-statement transaction
353   has been started, either explicitly, by means
354   of BEGIN or COMMIT AND CHAIN, or
355   implicitly, by the first transactional
356   statement, when autocommit=off.
357 */
358 #define SERVER_STATUS_IN_TRANS     1U
359 #define SERVER_STATUS_AUTOCOMMIT   2U	/* Server in auto_commit mode */
360 #define SERVER_MORE_RESULTS_EXISTS 8U   /* Multi query - next query exists */
361 #define SERVER_QUERY_NO_GOOD_INDEX_USED 16U
362 #define SERVER_QUERY_NO_INDEX_USED      32U
363 /**
364   The server was able to fulfill the clients request and opened a
365   read-only non-scrollable cursor for a query. This flag comes
366   in reply to COM_STMT_EXECUTE and COM_STMT_FETCH commands.
367 */
368 #define SERVER_STATUS_CURSOR_EXISTS 64U
369 /**
370   This flag is sent when a read-only cursor is exhausted, in reply to
371   COM_STMT_FETCH command.
372 */
373 #define SERVER_STATUS_LAST_ROW_SENT 128U
374 #define SERVER_STATUS_DB_DROPPED        256U /* A database was dropped */
375 #define SERVER_STATUS_NO_BACKSLASH_ESCAPES 512U
376 /**
377   Sent to the client if after a prepared statement reprepare
378   we discovered that the new statement returns a different
379   number of result set columns.
380 */
381 #define SERVER_STATUS_METADATA_CHANGED 1024U
382 #define SERVER_QUERY_WAS_SLOW          2048U
383 
384 /**
385   To mark ResultSet containing output parameter values.
386 */
387 #define SERVER_PS_OUT_PARAMS            4096U
388 
389 /**
390   Set at the same time as SERVER_STATUS_IN_TRANS if the started
391   multi-statement transaction is a read-only transaction. Cleared
392   when the transaction commits or aborts. Since this flag is sent
393   to clients in OK and EOF packets, the flag indicates the
394   transaction status at the end of command execution.
395 */
396 #define SERVER_STATUS_IN_TRANS_READONLY 8192U
397 
398 /**
399   This status flag, when on, implies that one of the state information has
400   changed on the server because of the execution of the last statement.
401 */
402 #define SERVER_SESSION_STATE_CHANGED    16384U
403 
404 #define SERVER_STATUS_ANSI_QUOTES       32768U
405 
406 /**
407   Server status flags that must be cleared when starting
408   execution of a new SQL statement.
409   Flags from this set are only added to the
410   current server status by the execution engine, but
411   never removed -- the execution engine expects them
412   to disappear automagically by the next command.
413 */
414 #define SERVER_STATUS_CLEAR_SET (SERVER_QUERY_NO_GOOD_INDEX_USED| \
415                                  SERVER_QUERY_NO_INDEX_USED|\
416                                  SERVER_MORE_RESULTS_EXISTS|\
417                                  SERVER_STATUS_METADATA_CHANGED |\
418                                  SERVER_QUERY_WAS_SLOW |\
419                                  SERVER_STATUS_DB_DROPPED |\
420                                  SERVER_STATUS_CURSOR_EXISTS|\
421                                  SERVER_STATUS_LAST_ROW_SENT|\
422                                  SERVER_SESSION_STATE_CHANGED)
423 
424 #define MYSQL_ERRMSG_SIZE	512
425 #define NET_READ_TIMEOUT	30		/* Timeout on read */
426 #define NET_WRITE_TIMEOUT	60		/* Timeout on write */
427 #define NET_WAIT_TIMEOUT	8*60*60		/* Wait for new query */
428 
429 struct st_vio;					/* Only C */
430 typedef struct st_vio Vio;
431 
432 #define MAX_TINYINT_WIDTH       3       /* Max width for a TINY w.o. sign */
433 #define MAX_SMALLINT_WIDTH      5       /* Max width for a SHORT w.o. sign */
434 #define MAX_MEDIUMINT_WIDTH     8       /* Max width for a INT24 w.o. sign */
435 #define MAX_INT_WIDTH           10      /* Max width for a LONG w.o. sign */
436 #define MAX_BIGINT_WIDTH        20      /* Max width for a LONGLONG */
437 #define MAX_CHAR_WIDTH		255	/* Max length for a CHAR column */
438 #define MAX_BLOB_WIDTH		16777216	/* Default width for blob */
439 
440 typedef struct st_net {
441 #if !defined(CHECK_EMBEDDED_DIFFERENCES) || !defined(EMBEDDED_LIBRARY)
442   Vio *vio;
443   unsigned char *buff,*buff_end,*write_pos,*read_pos;
444   my_socket fd;					/* For Perl DBI/dbd */
445   /*
446     The following variable is set if we are doing several queries in one
447     command ( as in LOAD TABLE ... FROM MASTER ),
448     and do not want to confuse the client with OK at the wrong time
449   */
450   unsigned long remain_in_buf,length, buf_length, where_b;
451   unsigned long max_packet,max_packet_size;
452   unsigned int pkt_nr,compress_pkt_nr;
453   unsigned int write_timeout, read_timeout, retry_count;
454   int fcntl;
455   unsigned int *return_status;
456   unsigned char reading_or_writing;
457   char save_char;
458   char net_skip_rest_factor;
459   my_bool thread_specific_malloc;
460   unsigned char compress;
461   my_bool unused3; /* Please remove with the next incompatible ABI change. */
462   /*
463     Pointer to query object in query cache, do not equal NULL (0) for
464     queries in cache that have not stored its results yet
465   */
466 #endif
467   void *thd; 	   /* Used by MariaDB server to avoid calling current_thd */
468   unsigned int last_errno;
469   unsigned char error;
470   my_bool unused4; /* Please remove with the next incompatible ABI change. */
471   my_bool unused5; /* Please remove with the next incompatible ABI change. */
472   /** Client library error message buffer. Actually belongs to struct MYSQL. */
473   char last_error[MYSQL_ERRMSG_SIZE];
474   /** Client library sqlstate buffer. Set along with the error message. */
475   char sqlstate[SQLSTATE_LENGTH+1];
476   void *extension;
477 } NET;
478 
479 
480 #define packet_error ~0UL
481 
482 enum enum_field_types { MYSQL_TYPE_DECIMAL, MYSQL_TYPE_TINY,
483 			MYSQL_TYPE_SHORT,  MYSQL_TYPE_LONG,
484 			MYSQL_TYPE_FLOAT,  MYSQL_TYPE_DOUBLE,
485 			MYSQL_TYPE_NULL,   MYSQL_TYPE_TIMESTAMP,
486 			MYSQL_TYPE_LONGLONG,MYSQL_TYPE_INT24,
487 			MYSQL_TYPE_DATE,   MYSQL_TYPE_TIME,
488 			MYSQL_TYPE_DATETIME, MYSQL_TYPE_YEAR,
489 			MYSQL_TYPE_NEWDATE, MYSQL_TYPE_VARCHAR,
490 			MYSQL_TYPE_BIT,
491                         /*
492                           mysql-5.6 compatibility temporal types.
493                           They're only used internally for reading RBR
494                           mysql-5.6 binary log events and mysql-5.6 frm files.
495                           They're never sent to the client.
496                         */
497                         MYSQL_TYPE_TIMESTAMP2,
498                         MYSQL_TYPE_DATETIME2,
499                         MYSQL_TYPE_TIME2,
500                         /* Compressed types are only used internally for RBR. */
501                         MYSQL_TYPE_BLOB_COMPRESSED= 140,
502                         MYSQL_TYPE_VARCHAR_COMPRESSED= 141,
503 
504                         MYSQL_TYPE_NEWDECIMAL=246,
505 			MYSQL_TYPE_ENUM=247,
506 			MYSQL_TYPE_SET=248,
507 			MYSQL_TYPE_TINY_BLOB=249,
508 			MYSQL_TYPE_MEDIUM_BLOB=250,
509 			MYSQL_TYPE_LONG_BLOB=251,
510 			MYSQL_TYPE_BLOB=252,
511 			MYSQL_TYPE_VAR_STRING=253,
512 			MYSQL_TYPE_STRING=254,
513 			MYSQL_TYPE_GEOMETRY=255
514 
515 };
516 
517 /* For backward compatibility */
518 #define CLIENT_MULTI_QUERIES    CLIENT_MULTI_STATEMENTS
519 #define FIELD_TYPE_DECIMAL     MYSQL_TYPE_DECIMAL
520 #define FIELD_TYPE_NEWDECIMAL  MYSQL_TYPE_NEWDECIMAL
521 #define FIELD_TYPE_TINY        MYSQL_TYPE_TINY
522 #define FIELD_TYPE_SHORT       MYSQL_TYPE_SHORT
523 #define FIELD_TYPE_LONG        MYSQL_TYPE_LONG
524 #define FIELD_TYPE_FLOAT       MYSQL_TYPE_FLOAT
525 #define FIELD_TYPE_DOUBLE      MYSQL_TYPE_DOUBLE
526 #define FIELD_TYPE_NULL        MYSQL_TYPE_NULL
527 #define FIELD_TYPE_TIMESTAMP   MYSQL_TYPE_TIMESTAMP
528 #define FIELD_TYPE_LONGLONG    MYSQL_TYPE_LONGLONG
529 #define FIELD_TYPE_INT24       MYSQL_TYPE_INT24
530 #define FIELD_TYPE_DATE        MYSQL_TYPE_DATE
531 #define FIELD_TYPE_TIME        MYSQL_TYPE_TIME
532 #define FIELD_TYPE_DATETIME    MYSQL_TYPE_DATETIME
533 #define FIELD_TYPE_YEAR        MYSQL_TYPE_YEAR
534 #define FIELD_TYPE_NEWDATE     MYSQL_TYPE_NEWDATE
535 #define FIELD_TYPE_ENUM        MYSQL_TYPE_ENUM
536 #define FIELD_TYPE_SET         MYSQL_TYPE_SET
537 #define FIELD_TYPE_TINY_BLOB   MYSQL_TYPE_TINY_BLOB
538 #define FIELD_TYPE_MEDIUM_BLOB MYSQL_TYPE_MEDIUM_BLOB
539 #define FIELD_TYPE_LONG_BLOB   MYSQL_TYPE_LONG_BLOB
540 #define FIELD_TYPE_BLOB        MYSQL_TYPE_BLOB
541 #define FIELD_TYPE_VAR_STRING  MYSQL_TYPE_VAR_STRING
542 #define FIELD_TYPE_STRING      MYSQL_TYPE_STRING
543 #define FIELD_TYPE_CHAR        MYSQL_TYPE_TINY
544 #define FIELD_TYPE_INTERVAL    MYSQL_TYPE_ENUM
545 #define FIELD_TYPE_GEOMETRY    MYSQL_TYPE_GEOMETRY
546 #define FIELD_TYPE_BIT         MYSQL_TYPE_BIT
547 
548 
549 /* Shutdown/kill enums and constants */
550 
551 /* Bits for THD::killable. */
552 #define MYSQL_SHUTDOWN_KILLABLE_CONNECT    (unsigned char)(1 << 0)
553 #define MYSQL_SHUTDOWN_KILLABLE_TRANS      (unsigned char)(1 << 1)
554 #define MYSQL_SHUTDOWN_KILLABLE_LOCK_TABLE (unsigned char)(1 << 2)
555 #define MYSQL_SHUTDOWN_KILLABLE_UPDATE     (unsigned char)(1 << 3)
556 
557 enum mysql_enum_shutdown_level {
558   /*
559     We want levels to be in growing order of hardness (because we use number
560     comparisons). Note that DEFAULT does not respect the growing property, but
561     it's ok.
562   */
563   SHUTDOWN_DEFAULT = 0,
564   /* wait for existing connections to finish */
565   SHUTDOWN_WAIT_CONNECTIONS= MYSQL_SHUTDOWN_KILLABLE_CONNECT,
566   /* wait for existing trans to finish */
567   SHUTDOWN_WAIT_TRANSACTIONS= MYSQL_SHUTDOWN_KILLABLE_TRANS,
568   /* wait for existing updates to finish (=> no partial MyISAM update) */
569   SHUTDOWN_WAIT_UPDATES= MYSQL_SHUTDOWN_KILLABLE_UPDATE,
570   /* flush InnoDB buffers and other storage engines' buffers*/
571   SHUTDOWN_WAIT_ALL_BUFFERS= (MYSQL_SHUTDOWN_KILLABLE_UPDATE << 1),
572   /* don't flush InnoDB buffers, flush other storage engines' buffers*/
573   SHUTDOWN_WAIT_CRITICAL_BUFFERS= (MYSQL_SHUTDOWN_KILLABLE_UPDATE << 1) + 1
574 };
575 
576 enum enum_cursor_type
577 {
578   CURSOR_TYPE_NO_CURSOR= 0,
579   CURSOR_TYPE_READ_ONLY= 1,
580   CURSOR_TYPE_FOR_UPDATE= 2,
581   CURSOR_TYPE_SCROLLABLE= 4
582 };
583 
584 
585 /* options for mysql_set_option */
586 enum enum_mysql_set_option
587 {
588   MYSQL_OPTION_MULTI_STATEMENTS_ON,
589   MYSQL_OPTION_MULTI_STATEMENTS_OFF
590 };
591 
592 /*
593   Type of state change information that the server can include in the Ok
594   packet.
595 */
596 enum enum_session_state_type
597 {
598   SESSION_TRACK_SYSTEM_VARIABLES,             /* Session system variables */
599   SESSION_TRACK_SCHEMA,                       /* Current schema */
600   SESSION_TRACK_STATE_CHANGE,                 /* track session state changes */
601   SESSION_TRACK_GTIDS,
602   SESSION_TRACK_TRANSACTION_CHARACTERISTICS,  /* Transaction chistics */
603   SESSION_TRACK_TRANSACTION_STATE,            /* Transaction state */
604   SESSION_TRACK_always_at_the_end             /* must be last */
605 };
606 
607 #define SESSION_TRACK_BEGIN SESSION_TRACK_SYSTEM_VARIABLES
608 
609 #define IS_SESSION_STATE_TYPE(T) \
610   (((int)(T) >= SESSION_TRACK_BEGIN) && ((T) < SESSION_TRACK_always_at_the_end))
611 
612 #define net_new_transaction(net) ((net)->pkt_nr=0)
613 
614 #ifdef __cplusplus
615 extern "C" {
616 #endif
617 
618 my_bool	my_net_init(NET *net, Vio* vio, void *thd, unsigned int my_flags);
619 void	my_net_local_init(NET *net);
620 void	net_end(NET *net);
621 void	net_clear(NET *net, my_bool clear_buffer);
622 my_bool net_realloc(NET *net, size_t length);
623 my_bool	net_flush(NET *net);
624 my_bool	my_net_write(NET *net,const unsigned char *packet, size_t len);
625 my_bool	net_write_command(NET *net,unsigned char command,
626 			  const unsigned char *header, size_t head_len,
627 			  const unsigned char *packet, size_t len);
628 int	net_real_write(NET *net,const unsigned char *packet, size_t len);
629 unsigned long my_net_read_packet(NET *net, my_bool read_from_server);
630 unsigned long my_net_read_packet_reallen(NET *net, my_bool read_from_server,
631                                          unsigned long* reallen);
632 #define my_net_read(A) my_net_read_packet((A), 0)
633 
634 #ifdef MY_GLOBAL_INCLUDED
635 void my_net_set_write_timeout(NET *net, uint timeout);
636 void my_net_set_read_timeout(NET *net, uint timeout);
637 #endif
638 
639 struct sockaddr;
640 int my_connect(my_socket s, const struct sockaddr *name, unsigned int namelen,
641 	       unsigned int timeout);
642 struct my_rnd_struct;
643 
644 #ifdef __cplusplus
645 }
646 #endif
647 
648   /* The following is for user defined functions */
649 
650 enum Item_result
651 {
652   STRING_RESULT=0, REAL_RESULT, INT_RESULT, ROW_RESULT, DECIMAL_RESULT,
653   TIME_RESULT
654 };
655 
656 typedef struct st_udf_args
657 {
658   unsigned int arg_count;		/* Number of arguments */
659   enum Item_result *arg_type;		/* Pointer to item_results */
660   char **args;				/* Pointer to argument */
661   unsigned long *lengths;		/* Length of string arguments */
662   char *maybe_null;			/* Set to 1 for all maybe_null args */
663   const char **attributes;              /* Pointer to attribute name */
664   unsigned long *attribute_lengths;     /* Length of attribute arguments */
665   void *extension;
666 } UDF_ARGS;
667 
668   /* This holds information about the result */
669 
670 typedef struct st_udf_init
671 {
672   my_bool maybe_null;          /* 1 if function can return NULL */
673   unsigned int decimals;       /* for real functions */
674   unsigned long max_length;    /* For string functions */
675   char *ptr;                   /* free pointer for function data */
676   my_bool const_item;          /* 1 if function always returns the same value */
677   void *extension;
678 } UDF_INIT;
679 /*
680   TODO: add a notion for determinism of the UDF.
681   See Item_udf_func::update_used_tables ()
682 */
683 
684   /* Constants when using compression */
685 #define NET_HEADER_SIZE 4		/* standard header size */
686 #define COMP_HEADER_SIZE 3		/* compression header extra size */
687 
688   /* Prototypes to password functions */
689 
690 #ifdef __cplusplus
691 extern "C" {
692 #endif
693 
694 /*
695   These functions are used for authentication by client and server and
696   implemented in sql/password.c
697 */
698 
699 void create_random_string(char *to, unsigned int length,
700                           struct my_rnd_struct *rand_st);
701 
702 void hash_password(unsigned long *to, const char *password, unsigned int password_len);
703 void make_scrambled_password_323(char *to, const char *password);
704 void scramble_323(char *to, const char *message, const char *password);
705 my_bool check_scramble_323(const unsigned char *reply, const char *message,
706                            unsigned long *salt);
707 void get_salt_from_password_323(unsigned long *res, const char *password);
708 void make_scrambled_password(char *to, const char *password);
709 void scramble(char *to, const char *message, const char *password);
710 my_bool check_scramble(const unsigned char *reply, const char *message,
711                        const unsigned char *hash_stage2);
712 void get_salt_from_password(unsigned char *res, const char *password);
713 char *octet2hex(char *to, const char *str, size_t len);
714 
715 /* end of password.c */
716 
717 char *get_tty_password(const char *opt_message);
718 void get_tty_password_buff(const char *opt_message, char *to, size_t length);
719 const char *mysql_errno_to_sqlstate(unsigned int mysql_errno);
720 
721 /* Some other useful functions */
722 
723 my_bool my_thread_init(void);
724 void my_thread_end(void);
725 
726 #ifdef MY_GLOBAL_INCLUDED
727 #include "pack.h"
728 #endif
729 
730 #ifdef __cplusplus
731 }
732 #endif
733 
734 #define NULL_LENGTH ~0UL /* For net_store_length */
735 #define MYSQL_STMT_HEADER       4U
736 #define MYSQL_LONG_DATA_HEADER  6U
737 
738 /*
739   If a float or double field have more than this number of decimals,
740   it's regarded as floating point field without any specific number of
741   decimals
742 */
743 
744 
745 #endif
746