sql_prepare.cpp
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上传日期:2022-05-23
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文件大小:57k
- /* Copyright (C) 1995-2002 MySQL AB
- This program is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
- (at your option) any later version.
- This program is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
- You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
- /**********************************************************************
- This file contains the implementation of prepare and executes.
- Prepare:
- - Server gets the query from client with command 'COM_PREPARE';
- in the following format:
- [COM_PREPARE:1] [query]
- - Parse the query and recognize any parameter markers '?' and
- store its information list in lex->param_list
- - Allocate a new statement for this prepare; and keep this in
- 'thd->prepared_statements' pool.
- - Without executing the query, return back to client the total
- number of parameters along with result-set metadata information
- (if any) in the following format:
- [STMT_ID:4]
- [Column_count:2]
- [Param_count:2]
- [Columns meta info] (if Column_count > 0)
- [Params meta info] (if Param_count > 0 ) (TODO : 4.1.1)
-
- Prepare-execute:
- - Server gets the command 'COM_EXECUTE' to execute the
- previously prepared query. If there is any param markers; then client
- will send the data in the following format:
- [COM_EXECUTE:1]
- [STMT_ID:4]
- [NULL_BITS:(param_count+7)/8)]
- [TYPES_SUPPLIED_BY_CLIENT(0/1):1]
- [[length]data]
- [[length]data] .. [[length]data].
- (Note: Except for string/binary types; all other types will not be
- supplied with length field)
- - Replace the param items with this new data. If it is a first execute
- or types altered by client; then setup the conversion routines.
- - Execute the query without re-parsing and send back the results
- to client
- Long data handling:
- - Server gets the long data in pieces with command type 'COM_LONG_DATA'.
- - The packet recieved will have the format as:
- [COM_LONG_DATA:1][STMT_ID:4][parameter_number:2][data]
- - data from the packet is appended to long data value buffer for this
- placeholder.
- - It's up to the client to check for read data ended. The server doesn't
- care; and also server doesn't notify to the client that it got the
- data or not; if there is any error; then during execute; the error
- will be returned
- ***********************************************************************/
- #include "mysql_priv.h"
- #include "sql_select.h" // for JOIN
- #include <m_ctype.h> // for isspace()
- #ifdef EMBEDDED_LIBRARY
- /* include MYSQL_BIND headers */
- #include <mysql.h>
- #endif
- /******************************************************************************
- Prepared_statement: statement which can contain placeholders
- ******************************************************************************/
- class Prepared_statement: public Statement
- {
- public:
- THD *thd;
- Item_param **param_array;
- uint param_count;
- uint last_errno;
- char last_error[MYSQL_ERRMSG_SIZE];
- #ifndef EMBEDDED_LIBRARY
- bool (*set_params)(Prepared_statement *st, uchar *data, uchar *data_end,
- uchar *read_pos, String *expanded_query);
- #else
- bool (*set_params_data)(Prepared_statement *st, String *expanded_query);
- #endif
- bool (*set_params_from_vars)(Prepared_statement *stmt,
- List<LEX_STRING>& varnames,
- String *expanded_query);
- public:
- Prepared_statement(THD *thd_arg);
- virtual ~Prepared_statement();
- void setup_set_params();
- virtual Item_arena::Type type() const;
- };
- static void execute_stmt(THD *thd, Prepared_statement *stmt,
- String *expanded_query, bool set_context);
- /******************************************************************************
- Implementation
- ******************************************************************************/
- inline bool is_param_null(const uchar *pos, ulong param_no)
- {
- return pos[param_no/8] & (1 << (param_no & 7));
- }
- enum { STMT_QUERY_LOG_LENGTH= 8192 };
- enum enum_send_error { DONT_SEND_ERROR= 0, SEND_ERROR };
- /*
- Seek prepared statement in statement map by id: returns zero if statement
- was not found, pointer otherwise.
- */
- static Prepared_statement *
- find_prepared_statement(THD *thd, ulong id, const char *where,
- enum enum_send_error se)
- {
- Statement *stmt= thd->stmt_map.find(id);
- if (stmt == 0 || stmt->type() != Item_arena::PREPARED_STATEMENT)
- {
- char llbuf[22];
- my_error(ER_UNKNOWN_STMT_HANDLER, MYF(0), 22, llstr(id, llbuf), where);
- if (se == SEND_ERROR)
- send_error(thd);
- return 0;
- }
- return (Prepared_statement *) stmt;
- }
- /*
- Send prepared stmt info to client after prepare
- */
- #ifndef EMBEDDED_LIBRARY
- static bool send_prep_stmt(Prepared_statement *stmt, uint columns)
- {
- NET *net= &stmt->thd->net;
- char buff[9];
- DBUG_ENTER("send_prep_stmt");
- buff[0]= 0; /* OK packet indicator */
- int4store(buff+1, stmt->id);
- int2store(buff+5, columns);
- int2store(buff+7, stmt->param_count);
- /*
- Send types and names of placeholders to the client
- XXX: fix this nasty upcast from List<Item_param> to List<Item>
- */
- DBUG_RETURN(my_net_write(net, buff, sizeof(buff)) ||
- (stmt->param_count &&
- stmt->thd->protocol_simple.send_fields((List<Item> *)
- &stmt->lex->param_list,
- 0)));
- }
- #else
- static bool send_prep_stmt(Prepared_statement *stmt,
- uint columns __attribute__((unused)))
- {
- THD *thd= stmt->thd;
- thd->client_stmt_id= stmt->id;
- thd->client_param_count= stmt->param_count;
- thd->net.last_errno= 0;
- return 0;
- }
- #endif /*!EMBEDDED_LIBRARY*/
- /*
- Read the length of the parameter data and return back to
- caller by positing the pointer to param data.
- */
- #ifndef EMBEDDED_LIBRARY
- static ulong get_param_length(uchar **packet, ulong len)
- {
- reg1 uchar *pos= *packet;
- if (len < 1)
- return 0;
- if (*pos < 251)
- {
- (*packet)++;
- return (ulong) *pos;
- }
- if (len < 3)
- return 0;
- if (*pos == 252)
- {
- (*packet)+=3;
- return (ulong) uint2korr(pos+1);
- }
- if (len < 4)
- return 0;
- if (*pos == 253)
- {
- (*packet)+=4;
- return (ulong) uint3korr(pos+1);
- }
- if (len < 5)
- return 0;
- (*packet)+=9; // Must be 254 when here
- /*
- In our client-server protocol all numbers bigger than 2^24
- stored as 8 bytes with uint8korr. Here we always know that
- parameter length is less than 2^4 so don't look at the second
- 4 bytes. But still we need to obey the protocol hence 9 in the
- assignment above.
- */
- return (ulong) uint4korr(pos+1);
- }
- #else
- #define get_param_length(packet, len) len
- #endif /*!EMBEDDED_LIBRARY*/
- /*
- Data conversion routines
- SYNOPSIS
- set_param_xx()
- param parameter item
- pos input data buffer
- len length of data in the buffer
- All these functions read the data from pos, convert it to requested type
- and assign to param; pos is advanced to predefined length.
- Make a note that the NULL handling is examined at first execution
- (i.e. when input types altered) and for all subsequent executions
- we don't read any values for this.
- RETURN VALUE
- none
- */
- static void set_param_tiny(Item_param *param, uchar **pos, ulong len)
- {
- #ifndef EMBEDDED_LIBRARY
- if (len < 1)
- return;
- #endif
- int8 value= (int8) **pos;
- param->set_int(param->unsigned_flag ? (longlong) ((uint8) value) :
- (longlong) value, 4);
- *pos+= 1;
- }
- static void set_param_short(Item_param *param, uchar **pos, ulong len)
- {
- int16 value;
- #ifndef EMBEDDED_LIBRARY
- if (len < 2)
- return;
- value= sint2korr(*pos);
- #else
- shortget(value, *pos);
- #endif
- param->set_int(param->unsigned_flag ? (longlong) ((uint16) value) :
- (longlong) value, 6);
- *pos+= 2;
- }
- static void set_param_int32(Item_param *param, uchar **pos, ulong len)
- {
- int32 value;
- #ifndef EMBEDDED_LIBRARY
- if (len < 4)
- return;
- value= sint4korr(*pos);
- #else
- longget(value, *pos);
- #endif
- param->set_int(param->unsigned_flag ? (longlong) ((uint32) value) :
- (longlong) value, 11);
- *pos+= 4;
- }
- static void set_param_int64(Item_param *param, uchar **pos, ulong len)
- {
- longlong value;
- #ifndef EMBEDDED_LIBRARY
- if (len < 8)
- return;
- value= (longlong) sint8korr(*pos);
- #else
- longlongget(value, *pos);
- #endif
- param->set_int(value, 21);
- *pos+= 8;
- }
- static void set_param_float(Item_param *param, uchar **pos, ulong len)
- {
- float data;
- #ifndef EMBEDDED_LIBRARY
- if (len < 4)
- return;
- float4get(data,*pos);
- #else
- floatget(data, *pos);
- #endif
- param->set_double((double) data);
- *pos+= 4;
- }
- static void set_param_double(Item_param *param, uchar **pos, ulong len)
- {
- double data;
- #ifndef EMBEDDED_LIBRARY
- if (len < 8)
- return;
- float8get(data,*pos);
- #else
- doubleget(data, *pos);
- #endif
- param->set_double((double) data);
- *pos+= 8;
- }
- #ifndef EMBEDDED_LIBRARY
- /*
- Read date/time/datetime parameter values from network (binary
- protocol). See writing counterparts of these functions in
- libmysql.c (store_param_{time,date,datetime}).
- */
- static void set_param_time(Item_param *param, uchar **pos, ulong len)
- {
- MYSQL_TIME tm;
- ulong length= get_param_length(pos, len);
- if (length >= 8)
- {
- uchar *to= *pos;
- uint day;
- tm.neg= (bool) to[0];
- day= (uint) sint4korr(to+1);
- tm.hour= (uint) to[5] + day * 24;
- tm.minute= (uint) to[6];
- tm.second= (uint) to[7];
- tm.second_part= (length > 8) ? (ulong) sint4korr(to+8) : 0;
- if (tm.hour > 838)
- {
- /* TODO: add warning 'Data truncated' here */
- tm.hour= 838;
- tm.minute= 59;
- tm.second= 59;
- }
- tm.day= tm.year= tm.month= 0;
- }
- else
- set_zero_time(&tm, MYSQL_TIMESTAMP_TIME);
- param->set_time(&tm, MYSQL_TIMESTAMP_TIME,
- MAX_TIME_WIDTH * MY_CHARSET_BIN_MB_MAXLEN);
- *pos+= length;
- }
- static void set_param_datetime(Item_param *param, uchar **pos, ulong len)
- {
- MYSQL_TIME tm;
- ulong length= get_param_length(pos, len);
- if (length >= 4)
- {
- uchar *to= *pos;
- tm.neg= 0;
- tm.year= (uint) sint2korr(to);
- tm.month= (uint) to[2];
- tm.day= (uint) to[3];
- if (length > 4)
- {
- tm.hour= (uint) to[4];
- tm.minute= (uint) to[5];
- tm.second= (uint) to[6];
- }
- else
- tm.hour= tm.minute= tm.second= 0;
- tm.second_part= (length > 7) ? (ulong) sint4korr(to+7) : 0;
- }
- else
- set_zero_time(&tm, MYSQL_TIMESTAMP_DATETIME);
- param->set_time(&tm, MYSQL_TIMESTAMP_DATETIME,
- MAX_DATETIME_WIDTH * MY_CHARSET_BIN_MB_MAXLEN);
- *pos+= length;
- }
- static void set_param_date(Item_param *param, uchar **pos, ulong len)
- {
- MYSQL_TIME tm;
- ulong length= get_param_length(pos, len);
- if (length >= 4)
- {
- uchar *to= *pos;
- tm.year= (uint) sint2korr(to);
- tm.month= (uint) to[2];
- tm.day= (uint) to[3];
- tm.hour= tm.minute= tm.second= 0;
- tm.second_part= 0;
- tm.neg= 0;
- }
- else
- set_zero_time(&tm, MYSQL_TIMESTAMP_DATE);
- param->set_time(&tm, MYSQL_TIMESTAMP_DATE,
- MAX_DATE_WIDTH * MY_CHARSET_BIN_MB_MAXLEN);
- *pos+= length;
- }
- #else/*!EMBEDDED_LIBRARY*/
- void set_param_time(Item_param *param, uchar **pos, ulong len)
- {
- MYSQL_TIME tm= *((MYSQL_TIME*)*pos);
- tm.hour+= tm.day * 24;
- tm.day= tm.year= tm.month= 0;
- if (tm.hour > 838)
- {
- /* TODO: add warning 'Data truncated' here */
- tm.hour= 838;
- tm.minute= 59;
- tm.second= 59;
- }
- param->set_time(&tm, MYSQL_TIMESTAMP_TIME,
- MAX_TIME_WIDTH * MY_CHARSET_BIN_MB_MAXLEN);
- }
- void set_param_datetime(Item_param *param, uchar **pos, ulong len)
- {
- MYSQL_TIME *to= (MYSQL_TIME*)*pos;
- param->set_time(to, MYSQL_TIMESTAMP_DATETIME,
- MAX_DATETIME_WIDTH * MY_CHARSET_BIN_MB_MAXLEN);
- }
- void set_param_date(Item_param *param, uchar **pos, ulong len)
- {
- MYSQL_TIME *to= (MYSQL_TIME*)*pos;
- param->set_time(to, MYSQL_TIMESTAMP_DATE,
- MAX_DATE_WIDTH * MY_CHARSET_BIN_MB_MAXLEN);
- }
- #endif /*!EMBEDDED_LIBRARY*/
- static void set_param_str(Item_param *param, uchar **pos, ulong len)
- {
- ulong length= get_param_length(pos, len);
- param->set_str((const char *)*pos, length);
- *pos+= length;
- }
- #undef get_param_length
- static void setup_one_conversion_function(THD *thd, Item_param *param,
- uchar param_type)
- {
- switch (param_type) {
- case MYSQL_TYPE_TINY:
- param->set_param_func= set_param_tiny;
- param->item_type= Item::INT_ITEM;
- param->item_result_type= INT_RESULT;
- break;
- case MYSQL_TYPE_SHORT:
- param->set_param_func= set_param_short;
- param->item_type= Item::INT_ITEM;
- param->item_result_type= INT_RESULT;
- break;
- case MYSQL_TYPE_LONG:
- param->set_param_func= set_param_int32;
- param->item_type= Item::INT_ITEM;
- param->item_result_type= INT_RESULT;
- break;
- case MYSQL_TYPE_LONGLONG:
- param->set_param_func= set_param_int64;
- param->item_type= Item::INT_ITEM;
- param->item_result_type= INT_RESULT;
- break;
- case MYSQL_TYPE_FLOAT:
- param->set_param_func= set_param_float;
- param->item_type= Item::REAL_ITEM;
- param->item_result_type= REAL_RESULT;
- break;
- case MYSQL_TYPE_DOUBLE:
- param->set_param_func= set_param_double;
- param->item_type= Item::REAL_ITEM;
- param->item_result_type= REAL_RESULT;
- break;
- case MYSQL_TYPE_TIME:
- param->set_param_func= set_param_time;
- param->item_type= Item::STRING_ITEM;
- param->item_result_type= STRING_RESULT;
- break;
- case MYSQL_TYPE_DATE:
- param->set_param_func= set_param_date;
- param->item_type= Item::STRING_ITEM;
- param->item_result_type= STRING_RESULT;
- break;
- case MYSQL_TYPE_DATETIME:
- case MYSQL_TYPE_TIMESTAMP:
- param->set_param_func= set_param_datetime;
- param->item_type= Item::STRING_ITEM;
- param->item_result_type= STRING_RESULT;
- break;
- case MYSQL_TYPE_TINY_BLOB:
- case MYSQL_TYPE_MEDIUM_BLOB:
- case MYSQL_TYPE_LONG_BLOB:
- case MYSQL_TYPE_BLOB:
- param->set_param_func= set_param_str;
- param->value.cs_info.character_set_of_placeholder= &my_charset_bin;
- param->value.cs_info.character_set_client=
- thd->variables.character_set_client;
- param->value.cs_info.final_character_set_of_str_value= &my_charset_bin;
- param->item_type= Item::STRING_ITEM;
- param->item_result_type= STRING_RESULT;
- break;
- default:
- /*
- The client library ensures that we won't get any other typecodes
- except typecodes above and typecodes for string types. Marking
- label as 'default' lets us to handle malformed packets as well.
- */
- {
- CHARSET_INFO *fromcs= thd->variables.character_set_client;
- CHARSET_INFO *tocs= thd->variables.collation_connection;
- uint32 dummy_offset;
- param->value.cs_info.character_set_of_placeholder= fromcs;
- param->value.cs_info.character_set_client= fromcs;
- /*
- Setup source and destination character sets so that they
- are different only if conversion is necessary: this will
- make later checks easier.
- */
- param->value.cs_info.final_character_set_of_str_value=
- String::needs_conversion(0, fromcs, tocs, &dummy_offset) ?
- tocs : fromcs;
- param->set_param_func= set_param_str;
- /*
- Exact value of max_length is not known unless data is converted to
- charset of connection, so we have to set it later.
- */
- param->item_type= Item::STRING_ITEM;
- param->item_result_type= STRING_RESULT;
- }
- }
- param->param_type= (enum enum_field_types) param_type;
- }
- #ifndef EMBEDDED_LIBRARY
- /*
- Update the parameter markers by reading data from client packet
- and if binary/update log is set, generate the valid query.
- */
- static bool insert_params_withlog(Prepared_statement *stmt, uchar *null_array,
- uchar *read_pos, uchar *data_end,
- String *query)
- {
- THD *thd= stmt->thd;
- Item_param **begin= stmt->param_array;
- Item_param **end= begin + stmt->param_count;
- uint32 length= 0;
- String str;
- const String *res;
- DBUG_ENTER("insert_params_withlog");
- if (query->copy(stmt->query, stmt->query_length, default_charset_info))
- DBUG_RETURN(1);
-
- for (Item_param **it= begin; it < end; ++it)
- {
- Item_param *param= *it;
- if (param->state != Item_param::LONG_DATA_VALUE)
- {
- if (is_param_null(null_array, it - begin))
- param->set_null();
- else
- {
- if (read_pos >= data_end)
- DBUG_RETURN(1);
- param->set_param_func(param, &read_pos, data_end - read_pos);
- }
- }
- res= param->query_val_str(&str);
- if (param->convert_str_value(thd))
- DBUG_RETURN(1); /* out of memory */
- if (query->replace(param->pos_in_query+length, 1, *res))
- DBUG_RETURN(1);
-
- length+= res->length()-1;
- }
- DBUG_RETURN(0);
- }
- static bool insert_params(Prepared_statement *stmt, uchar *null_array,
- uchar *read_pos, uchar *data_end,
- String *expanded_query)
- {
- Item_param **begin= stmt->param_array;
- Item_param **end= begin + stmt->param_count;
- DBUG_ENTER("insert_params");
- for (Item_param **it= begin; it < end; ++it)
- {
- Item_param *param= *it;
- if (param->state != Item_param::LONG_DATA_VALUE)
- {
- if (is_param_null(null_array, it - begin))
- param->set_null();
- else
- {
- if (read_pos >= data_end)
- DBUG_RETURN(1);
- param->set_param_func(param, &read_pos, data_end - read_pos);
- }
- }
- if (param->convert_str_value(stmt->thd))
- DBUG_RETURN(1); /* out of memory */
- }
- DBUG_RETURN(0);
- }
- static bool setup_conversion_functions(Prepared_statement *stmt,
- uchar **data, uchar *data_end)
- {
- /* skip null bits */
- uchar *read_pos= *data + (stmt->param_count+7) / 8;
- DBUG_ENTER("setup_conversion_functions");
- if (*read_pos++) //types supplied / first execute
- {
- /*
- First execute or types altered by the client, setup the
- conversion routines for all parameters (one time)
- */
- Item_param **it= stmt->param_array;
- Item_param **end= it + stmt->param_count;
- THD *thd= stmt->thd;
- for (; it < end; ++it)
- {
- ushort typecode;
- const uint signed_bit= 1 << 15;
- if (read_pos >= data_end)
- DBUG_RETURN(1);
- typecode= sint2korr(read_pos);
- read_pos+= 2;
- (**it).unsigned_flag= test(typecode & signed_bit);
- setup_one_conversion_function(thd, *it, (uchar) (typecode & ~signed_bit));
- }
- }
- *data= read_pos;
- DBUG_RETURN(0);
- }
- #else
- static bool emb_insert_params(Prepared_statement *stmt, String *expanded_query)
- {
- THD *thd= stmt->thd;
- Item_param **it= stmt->param_array;
- Item_param **end= it + stmt->param_count;
- MYSQL_BIND *client_param= stmt->thd->client_params;
- DBUG_ENTER("emb_insert_params");
- for (; it < end; ++it, ++client_param)
- {
- Item_param *param= *it;
- setup_one_conversion_function(thd, param, client_param->buffer_type);
- if (param->state != Item_param::LONG_DATA_VALUE)
- {
- if (*client_param->is_null)
- param->set_null();
- else
- {
- uchar *buff= (uchar*) client_param->buffer;
- param->unsigned_flag= client_param->is_unsigned;
- param->set_param_func(param, &buff,
- client_param->length ?
- *client_param->length :
- client_param->buffer_length);
- }
- }
- if (param->convert_str_value(thd))
- DBUG_RETURN(1); /* out of memory */
- }
- DBUG_RETURN(0);
- }
- static bool emb_insert_params_withlog(Prepared_statement *stmt, String *query)
- {
- THD *thd= stmt->thd;
- Item_param **it= stmt->param_array;
- Item_param **end= it + stmt->param_count;
- MYSQL_BIND *client_param= thd->client_params;
- String str;
- const String *res;
- uint32 length= 0;
- DBUG_ENTER("emb_insert_params_withlog");
- if (query->copy(stmt->query, stmt->query_length, default_charset_info))
- DBUG_RETURN(1);
-
- for (; it < end; ++it, ++client_param)
- {
- Item_param *param= *it;
- setup_one_conversion_function(thd, param, client_param->buffer_type);
- if (param->state != Item_param::LONG_DATA_VALUE)
- {
- if (*client_param->is_null)
- param->set_null();
- else
- {
- uchar *buff= (uchar*)client_param->buffer;
- param->unsigned_flag= client_param->is_unsigned;
- param->set_param_func(param, &buff,
- client_param->length ?
- *client_param->length :
- client_param->buffer_length);
- }
- }
- res= param->query_val_str(&str);
- if (param->convert_str_value(thd))
- DBUG_RETURN(1); /* out of memory */
- if (query->replace(param->pos_in_query+length, 1, *res))
- DBUG_RETURN(1);
- length+= res->length()-1;
- }
- DBUG_RETURN(0);
- }
- #endif /*!EMBEDDED_LIBRARY*/
- /*
- Set prepared statement parameters from user variables.
- SYNOPSIS
- insert_params_from_vars()
- stmt Statement
- varnames List of variables. Caller must ensure that number of variables
- in the list is equal to number of statement parameters
- query Ignored
- */
- static bool insert_params_from_vars(Prepared_statement *stmt,
- List<LEX_STRING>& varnames,
- String *query __attribute__((unused)))
- {
- Item_param **begin= stmt->param_array;
- Item_param **end= begin + stmt->param_count;
- user_var_entry *entry;
- LEX_STRING *varname;
- List_iterator<LEX_STRING> var_it(varnames);
- DBUG_ENTER("insert_params_from_vars");
- for (Item_param **it= begin; it < end; ++it)
- {
- Item_param *param= *it;
- varname= var_it++;
- entry= (user_var_entry*)hash_search(&stmt->thd->user_vars,
- (byte*) varname->str,
- varname->length);
- if (param->set_from_user_var(stmt->thd, entry) ||
- param->convert_str_value(stmt->thd))
- DBUG_RETURN(1);
- }
- DBUG_RETURN(0);
- }
- /*
- Do the same as insert_params_from_vars but also construct query text for
- binary log.
- SYNOPSIS
- insert_params_from_vars()
- stmt Statement
- varnames List of variables. Caller must ensure that number of variables
- in the list is equal to number of statement parameters
- query The query with parameter markers replaced with their values
- */
- static bool insert_params_from_vars_with_log(Prepared_statement *stmt,
- List<LEX_STRING>& varnames,
- String *query)
- {
- Item_param **begin= stmt->param_array;
- Item_param **end= begin + stmt->param_count;
- user_var_entry *entry;
- LEX_STRING *varname;
- DBUG_ENTER("insert_params_from_vars");
- List_iterator<LEX_STRING> var_it(varnames);
- String buf;
- const String *val;
- uint32 length= 0;
- if (query->copy(stmt->query, stmt->query_length, default_charset_info))
- DBUG_RETURN(1);
- for (Item_param **it= begin; it < end; ++it)
- {
- Item_param *param= *it;
- varname= var_it++;
- if (get_var_with_binlog(stmt->thd, *varname, &entry))
- DBUG_RETURN(1);
- if (param->set_from_user_var(stmt->thd, entry))
- DBUG_RETURN(1);
- /* Insert @'escaped-varname' instead of parameter in the query */
- if (entry)
- {
- char *begin, *ptr;
- buf.length(0);
- if (buf.reserve(entry->name.length*2+3))
- DBUG_RETURN(1);
- begin= ptr= buf.c_ptr_quick();
- *ptr++= '@';
- *ptr++= ''';
- ptr+= escape_string_for_mysql(&my_charset_utf8_general_ci,
- ptr, entry->name.str, entry->name.length);
- *ptr++= ''';
- buf.length(ptr - begin);
- val= &buf;
- }
- else
- val= &my_null_string;
- if (param->convert_str_value(stmt->thd))
- DBUG_RETURN(1); /* out of memory */
- if (query->replace(param->pos_in_query+length, 1, *val))
- DBUG_RETURN(1);
- length+= val->length()-1;
- }
- DBUG_RETURN(0);
- }
- /*
- Validate INSERT statement:
- SYNOPSIS
- mysql_test_insert()
- stmt prepared statemen handler
- tables list of tables queries
- RETURN VALUE
- 0 ok
- 1 error, sent to the client
- -1 error, not sent to client
- */
- static int mysql_test_insert(Prepared_statement *stmt,
- TABLE_LIST *table_list,
- List<Item> &fields,
- List<List_item> &values_list,
- List<Item> &update_fields,
- List<Item> &update_values,
- enum_duplicates duplic)
- {
- THD *thd= stmt->thd;
- LEX *lex= stmt->lex;
- List_iterator_fast<List_item> its(values_list);
- List_item *values;
- int res= -1;
- TABLE_LIST *insert_table_list=
- (TABLE_LIST*) lex->select_lex.table_list.first;
- DBUG_ENTER("mysql_test_insert");
- if ((res= insert_precheck(thd, table_list)))
- DBUG_RETURN(res);
- /*
- open temporary memory pool for temporary data allocated by derived
- tables & preparation procedure
- Note that this is done without locks (should not be needed as we will not
- access any data here)
- If we would use locks, then we have to ensure we are not using
- TL_WRITE_DELAYED as having two such locks can cause table corruption.
- */
- if (open_normal_and_derived_tables(thd, table_list))
- {
- DBUG_RETURN(-1);
- }
- if ((values= its++))
- {
- uint value_count;
- ulong counter= 0;
- table_list->table->insert_values=(byte *)1; // don't allocate insert_values
- if ((res= mysql_prepare_insert(thd, table_list, insert_table_list,
- insert_table_list,
- table_list->table, fields, values,
- update_fields, update_values, duplic)))
- goto error;
- value_count= values->elements;
- its.rewind();
- while ((values= its++))
- {
- counter++;
- if (values->elements != value_count)
- {
- my_printf_error(ER_WRONG_VALUE_COUNT_ON_ROW,
- ER(ER_WRONG_VALUE_COUNT_ON_ROW),
- MYF(0), counter);
- goto error;
- }
- if (setup_fields(thd, 0, insert_table_list, *values, 0, 0, 0))
- goto error;
- }
- }
- res= 0;
- error:
- lex->unit.cleanup();
- table_list->table->insert_values=0;
- DBUG_RETURN(res);
- }
- /*
- Validate UPDATE statement
- SYNOPSIS
- mysql_test_update()
- stmt prepared statemen handler
- tables list of tables queries
- RETURN VALUE
- 0 success
- 1 error, sent to client
- -1 error, not sent to client
- */
- static int mysql_test_update(Prepared_statement *stmt,
- TABLE_LIST *table_list)
- {
- int res;
- THD *thd= stmt->thd;
- SELECT_LEX *select= &stmt->lex->select_lex;
- DBUG_ENTER("mysql_test_update");
- if ((res= update_precheck(thd, table_list)))
- DBUG_RETURN(res);
- if (open_and_lock_tables(thd, table_list))
- res= -1;
- else
- {
- TABLE_LIST *update_table_list= (TABLE_LIST *)select->table_list.first;
- if (!(res= mysql_prepare_update(thd, table_list,
- update_table_list,
- &select->where,
- select->order_list.elements,
- (ORDER *) select->order_list.first)))
- {
- if (setup_fields(thd, 0, update_table_list,
- select->item_list, 1, 0, 0) ||
- setup_fields(thd, 0, update_table_list,
- stmt->lex->value_list, 0, 0, 0))
- res= -1;
- }
- stmt->lex->unit.cleanup();
- }
- /* TODO: here we should send types of placeholders to the client. */
- DBUG_RETURN(res);
- }
- /*
- Validate DELETE statement
- SYNOPSIS
- mysql_test_delete()
- stmt prepared statemen handler
- tables list of tables queries
- RETURN VALUE
- 0 success
- 1 error, sent to client
- -1 error, not sent to client
- */
- static int mysql_test_delete(Prepared_statement *stmt,
- TABLE_LIST *table_list)
- {
- int res;
- THD *thd= stmt->thd;
- LEX *lex= stmt->lex;
- DBUG_ENTER("mysql_test_delete");
- if ((res= delete_precheck(thd, table_list)))
- DBUG_RETURN(res);
- if (open_and_lock_tables(thd, table_list))
- res= -1;
- else
- {
- res= mysql_prepare_delete(thd, table_list, &lex->select_lex.where);
- lex->unit.cleanup();
- }
- /* TODO: here we should send types of placeholders to the client. */
- DBUG_RETURN(res);
- }
- /*
- Validate SELECT statement.
- In case of success, if this query is not EXPLAIN, send column list info
- back to client.
- SYNOPSIS
- mysql_test_select()
- stmt prepared statemen handler
- tables list of tables queries
- RETURN VALUE
- 0 success
- 1 error, sent to client
- -1 error, not sent to client
- */
- static int mysql_test_select(Prepared_statement *stmt,
- TABLE_LIST *tables, bool text_protocol)
- {
- THD *thd= stmt->thd;
- LEX *lex= stmt->lex;
- SELECT_LEX_UNIT *unit= &lex->unit;
- int result= 1;
- DBUG_ENTER("mysql_test_select");
- #ifndef NO_EMBEDDED_ACCESS_CHECKS
- ulong privilege= lex->exchange ? SELECT_ACL | FILE_ACL : SELECT_ACL;
- if (tables)
- {
- if (check_table_access(thd, privilege, tables,0))
- DBUG_RETURN(1);
- }
- else if (check_access(thd, privilege, any_db,0,0,0))
- DBUG_RETURN(1);
- #endif
- if (!lex->result && !(lex->result= new (stmt->mem_root) select_send))
- {
- send_error(thd);
- goto err;
- }
- if (open_and_lock_tables(thd, tables))
- {
- send_error(thd);
- goto err;
- }
- thd->used_tables= 0; // Updated by setup_fields
- // JOIN::prepare calls
- if (unit->prepare(thd, 0, 0, ""))
- {
- send_error(thd);
- goto err_prep;
- }
- if (!text_protocol)
- {
- if (lex->describe)
- {
- if (send_prep_stmt(stmt, 0) || thd->protocol->flush())
- goto err_prep;
- }
- else
- {
- /* Make copy of item list, as change_columns may change it */
- List<Item> fields(lex->select_lex.item_list);
- /* Change columns if a procedure like analyse() */
- if (unit->last_procedure &&
- unit->last_procedure->change_columns(fields))
- goto err_prep;
- /*
- We can use lex->result as it should've been
- prepared in unit->prepare call above.
- */
- if (send_prep_stmt(stmt, lex->result->field_count(fields)) ||
- lex->result->send_fields(fields, 0) ||
- thd->protocol->flush())
- goto err_prep;
- }
- }
- result= 0; // ok
- err_prep:
- unit->cleanup();
- err:
- DBUG_RETURN(result);
- }
- /*
- Validate and prepare for execution DO statement expressions
- SYNOPSIS
- mysql_test_do_fields()
- stmt prepared statemen handler
- tables list of tables queries
- values list of expressions
- RETURN VALUE
- 0 success
- 1 error, sent to client
- -1 error, not sent to client
- */
- static int mysql_test_do_fields(Prepared_statement *stmt,
- TABLE_LIST *tables,
- List<Item> *values)
- {
- DBUG_ENTER("mysql_test_do_fields");
- THD *thd= stmt->thd;
- int res= 0;
- if (tables && (res= check_table_access(thd, SELECT_ACL, tables, 0)))
- DBUG_RETURN(res);
- if (tables && (res= open_and_lock_tables(thd, tables)))
- {
- DBUG_RETURN(res);
- }
- res= setup_fields(thd, 0, 0, *values, 0, 0, 0);
- stmt->lex->unit.cleanup();
- if (res)
- DBUG_RETURN(-1);
- DBUG_RETURN(0);
- }
- /*
- Validate and prepare for execution SET statement expressions
- SYNOPSIS
- mysql_test_set_fields()
- stmt prepared statemen handler
- tables list of tables queries
- values list of expressions
- RETURN VALUE
- 0 success
- 1 error, sent to client
- -1 error, not sent to client
- */
- static int mysql_test_set_fields(Prepared_statement *stmt,
- TABLE_LIST *tables,
- List<set_var_base> *var_list)
- {
- DBUG_ENTER("mysql_test_set_fields");
- List_iterator_fast<set_var_base> it(*var_list);
- THD *thd= stmt->thd;
- set_var_base *var;
- int res= 0;
- if (tables && (res= check_table_access(thd, SELECT_ACL, tables, 0)))
- DBUG_RETURN(res);
- if (tables && (res= open_and_lock_tables(thd, tables)))
- goto error;
- while ((var= it++))
- {
- if (var->light_check(thd))
- {
- stmt->lex->unit.cleanup();
- res= -1;
- goto error;
- }
- }
- error:
- stmt->lex->unit.cleanup();
- DBUG_RETURN(res);
- }
- /*
- Check internal SELECT of the prepared command
- SYNOPSIS
- select_like_statement_test()
- stmt - prepared table handler
- tables - global list of tables
- RETURN VALUE
- 0 success
- 1 error, sent to client
- -1 error, not sent to client
- */
- static int select_like_statement_test(Prepared_statement *stmt,
- TABLE_LIST *tables)
- {
- DBUG_ENTER("select_like_statement_test");
- THD *thd= stmt->thd;
- LEX *lex= stmt->lex;
- int res= 0;
- if (tables && (res= open_and_lock_tables(thd, tables)))
- goto end;
- thd->used_tables= 0; // Updated by setup_fields
- // JOIN::prepare calls
- if (lex->unit.prepare(thd, 0, 0, ""))
- {
- res= thd->net.report_error ? -1 : 1;
- }
- end:
- lex->unit.cleanup();
- DBUG_RETURN(res);
- }
- /*
- Validate and prepare for execution CREATE TABLE statement
- SYNOPSIS
- mysql_test_create_table()
- stmt prepared statemen handler
- tables list of tables queries
- RETURN VALUE
- 0 success
- 1 error, sent to client
- -1 error, not sent to client
- */
- static int mysql_test_create_table(Prepared_statement *stmt,
- TABLE_LIST *tables)
- {
- DBUG_ENTER("mysql_test_create_table");
- THD *thd= stmt->thd;
- LEX *lex= stmt->lex;
- SELECT_LEX *select_lex= &lex->select_lex;
- int res= 0;
- /* Skip first table, which is the table we are creating */
- TABLE_LIST *create_table, *create_table_local;
- tables= lex->unlink_first_table(tables, &create_table,
- &create_table_local);
- if (!(res= create_table_precheck(thd, tables, create_table)) &&
- select_lex->item_list.elements)
- {
- select_lex->resolve_mode= SELECT_LEX::SELECT_MODE;
- res= select_like_statement_test(stmt, tables);
- select_lex->resolve_mode= SELECT_LEX::NOMATTER_MODE;
- }
- /* put tables back for PS rexecuting */
- tables= lex->link_first_table_back(tables, create_table,
- create_table_local);
- DBUG_RETURN(res);
- }
- /*
- Validate and prepare for execution multi update statement
- SYNOPSIS
- mysql_test_multiupdate()
- stmt prepared statemen handler
- tables list of tables queries
- RETURN VALUE
- 0 success
- 1 error, sent to client
- -1 error, not sent to client
- */
- static int mysql_test_multiupdate(Prepared_statement *stmt,
- TABLE_LIST *tables)
- {
- int res;
- if ((res= multi_update_precheck(stmt->thd, tables)))
- return res;
- return select_like_statement_test(stmt, tables);
- }
- /*
- Validate and prepare for execution multi delete statement
- SYNOPSIS
- mysql_test_multidelete()
- stmt prepared statemen handler
- tables list of tables queries
- RETURN VALUE
- 0 success
- 1 error, sent to client
- -1 error, not sent to client
- */
- static int mysql_test_multidelete(Prepared_statement *stmt,
- TABLE_LIST *tables)
- {
- int res;
- stmt->thd->lex->current_select= &stmt->thd->lex->select_lex;
- if (add_item_to_list(stmt->thd, new Item_null()))
- return -1;
- uint fake_counter;
- if ((res= multi_delete_precheck(stmt->thd, tables, &fake_counter)))
- return res;
- return select_like_statement_test(stmt, tables);
- }
- /*
- Validate and prepare for execution INSERT ... SELECT statement
- SYNOPSIS
- mysql_test_insert_select()
- stmt prepared statemen handler
- tables list of tables queries
- RETURN VALUE
- 0 success
- 1 error, sent to client
- -1 error, not sent to client
- */
- static int mysql_test_insert_select(Prepared_statement *stmt,
- TABLE_LIST *tables)
- {
- int res;
- LEX *lex= stmt->lex;
- if ((res= insert_precheck(stmt->thd, tables)))
- return res;
- TABLE_LIST *first_local_table=
- (TABLE_LIST *)lex->select_lex.table_list.first;
- /* Skip first table, which is the table we are inserting in */
- lex->select_lex.table_list.first= (byte*) first_local_table->next;
- /*
- insert/replace from SELECT give its SELECT_LEX for SELECT,
- and item_list belong to SELECT
- */
- lex->select_lex.resolve_mode= SELECT_LEX::SELECT_MODE;
- res= select_like_statement_test(stmt, tables);
- /* revert changes*/
- lex->select_lex.table_list.first= (byte*) first_local_table;
- lex->select_lex.resolve_mode= SELECT_LEX::INSERT_MODE;
- return res;
- }
- /*
- Send the prepare query results back to client
- SYNOPSIS
- send_prepare_results()
- stmt prepared statement
- RETURN VALUE
- 0 success
- 1 error, sent to client
- */
- static int send_prepare_results(Prepared_statement *stmt, bool text_protocol)
- {
- THD *thd= stmt->thd;
- LEX *lex= stmt->lex;
- SELECT_LEX *select_lex= &lex->select_lex;
- TABLE_LIST *tables=(TABLE_LIST*) select_lex->table_list.first;
- enum enum_sql_command sql_command= lex->sql_command;
- int res= 0;
- DBUG_ENTER("send_prepare_results");
- DBUG_PRINT("enter",("command: %d, param_count: %ld",
- sql_command, stmt->param_count));
- if ((&lex->select_lex != lex->all_selects_list ||
- lex->time_zone_tables_used) &&
- lex->unit.create_total_list(thd, lex, &tables))
- DBUG_RETURN(1);
- switch (sql_command) {
- case SQLCOM_REPLACE:
- case SQLCOM_INSERT:
- res= mysql_test_insert(stmt, tables, lex->field_list,
- lex->many_values,
- select_lex->item_list, lex->value_list,
- lex->duplicates);
- break;
- case SQLCOM_UPDATE:
- res= mysql_test_update(stmt, tables);
- break;
- case SQLCOM_DELETE:
- res= mysql_test_delete(stmt, tables);
- break;
- case SQLCOM_SELECT:
- if ((res= mysql_test_select(stmt, tables, text_protocol)))
- goto error;
- /* Statement and field info has already been sent */
- DBUG_RETURN(0);
- case SQLCOM_CREATE_TABLE:
- res= mysql_test_create_table(stmt, tables);
- break;
-
- case SQLCOM_DO:
- res= mysql_test_do_fields(stmt, tables, lex->insert_list);
- break;
- case SQLCOM_SET_OPTION:
- res= mysql_test_set_fields(stmt, tables, &lex->var_list);
- break;
- case SQLCOM_DELETE_MULTI:
- res= mysql_test_multidelete(stmt, tables);
- break;
-
- case SQLCOM_UPDATE_MULTI:
- res= mysql_test_multiupdate(stmt, tables);
- break;
- case SQLCOM_INSERT_SELECT:
- case SQLCOM_REPLACE_SELECT:
- res= mysql_test_insert_select(stmt, tables);
- break;
- case SQLCOM_SHOW_DATABASES:
- case SQLCOM_SHOW_PROCESSLIST:
- case SQLCOM_SHOW_STORAGE_ENGINES:
- case SQLCOM_SHOW_PRIVILEGES:
- case SQLCOM_SHOW_COLUMN_TYPES:
- case SQLCOM_SHOW_STATUS:
- case SQLCOM_SHOW_VARIABLES:
- case SQLCOM_SHOW_LOGS:
- case SQLCOM_SHOW_TABLES:
- case SQLCOM_SHOW_OPEN_TABLES:
- case SQLCOM_SHOW_CHARSETS:
- case SQLCOM_SHOW_COLLATIONS:
- case SQLCOM_SHOW_FIELDS:
- case SQLCOM_SHOW_KEYS:
- case SQLCOM_SHOW_CREATE_DB:
- case SQLCOM_SHOW_GRANTS:
- case SQLCOM_DROP_TABLE:
- case SQLCOM_RENAME_TABLE:
- break;
- default:
- /*
- All other is not supported yet
- */
- res= -1;
- my_error(ER_UNSUPPORTED_PS, MYF(0));
- goto error;
- }
- if (res == 0)
- DBUG_RETURN(text_protocol? 0 : (send_prep_stmt(stmt, 0) ||
- thd->protocol->flush()));
- error:
- if (res < 0)
- send_error(thd, thd->killed ? ER_SERVER_SHUTDOWN : 0);
- DBUG_RETURN(1);
- }
- /*
- Initialize array of parameters in statement from LEX.
- (We need to have quick access to items by number in mysql_stmt_get_longdata).
- This is to avoid using malloc/realloc in the parser.
- */
- static bool init_param_array(Prepared_statement *stmt)
- {
- LEX *lex= stmt->lex;
- THD *thd= stmt->thd;
- if ((stmt->param_count= lex->param_list.elements))
- {
- if (stmt->param_count > (uint) UINT_MAX16)
- {
- /* Error code to be defined in 5.0 */
- send_error(thd, ER_UNKNOWN_ERROR,
- "Prepared statement contains too many placeholders.");
- return 1;
- }
- Item_param **to;
- List_iterator<Item_param> param_iterator(lex->param_list);
- /* Use thd->mem_root as it points at statement mem_root */
- stmt->param_array= (Item_param **)
- alloc_root(stmt->thd->mem_root,
- sizeof(Item_param*) * stmt->param_count);
- if (!stmt->param_array)
- {
- send_error(thd, ER_OUT_OF_RESOURCES);
- return 1;
- }
- for (to= stmt->param_array;
- to < stmt->param_array + stmt->param_count;
- ++to)
- {
- *to= param_iterator++;
- }
- }
- return 0;
- }
- /*
- Given a query string with parameter markers, create a Prepared Statement
- from it and send PS info back to the client.
-
- SYNOPSIS
- mysql_stmt_prepare()
- packet query to be prepared
- packet_length query string length, including ignored trailing NULL or
- quote char.
- name NULL or statement name. For unnamed statements binary PS
- protocol is used, for named statements text protocol is
- used.
- RETURN
- 0 OK, statement prepared successfully
- other Error
-
- NOTES
- This function parses the query and sends the total number of parameters
- and resultset metadata information back to client (if any), without
- executing the query i.e. without any log/disk writes. This allows the
- queries to be re-executed without re-parsing during execute.
- If parameter markers are found in the query, then store the information
- using Item_param along with maintaining a list in lex->param_array, so
- that a fast and direct retrieval can be made without going through all
- field items.
-
- */
- int mysql_stmt_prepare(THD *thd, char *packet, uint packet_length,
- LEX_STRING *name)
- {
- LEX *lex;
- Prepared_statement *stmt= new Prepared_statement(thd);
- int error;
- DBUG_ENTER("mysql_stmt_prepare");
- DBUG_PRINT("prep_query", ("%s", packet));
- /*
- If this is an SQLCOM_PREPARE, we also increase Com_prepare_sql.
- However, it seems handy if com_stmt_prepare is increased always,
- no matter what kind of prepare is processed.
- */
- statistic_increment(com_stmt_prepare, &LOCK_status);
- if (stmt == 0)
- {
- send_error(thd, ER_OUT_OF_RESOURCES);
- DBUG_RETURN(1);
- }
- if (name)
- {
- stmt->name.length= name->length;
- if (!(stmt->name.str= memdup_root(stmt->mem_root, (char*)name->str,
- name->length)))
- {
- delete stmt;
- send_error(thd, ER_OUT_OF_RESOURCES);
- DBUG_RETURN(1);
- }
- }
- if (thd->stmt_map.insert(stmt))
- {
- delete stmt;
- send_error(thd, ER_OUT_OF_RESOURCES);
- DBUG_RETURN(1);
- }
- thd->set_n_backup_statement(stmt, &thd->stmt_backup);
- thd->set_n_backup_item_arena(stmt, &thd->stmt_backup);
- if (alloc_query(thd, packet, packet_length))
- {
- thd->restore_backup_statement(stmt, &thd->stmt_backup);
- thd->restore_backup_item_arena(stmt, &thd->stmt_backup);
- /* Statement map deletes statement on erase */
- thd->stmt_map.erase(stmt);
- send_error(thd, ER_OUT_OF_RESOURCES);
- DBUG_RETURN(1);
- }
- mysql_log.write(thd, thd->command, "[%lu] %s", stmt->id, packet);
- thd->current_arena= stmt;
- mysql_init_query(thd, (uchar *) thd->query, thd->query_length);
- /* Reset warnings from previous command */
- mysql_reset_errors(thd);
- lex= thd->lex;
- lex->safe_to_cache_query= 0;
- error= yyparse((void *)thd) || thd->is_fatal_error ||
- thd->net.report_error || init_param_array(stmt);
- /*
- While doing context analysis of the query (in send_prepare_results) we
- allocate a lot of additional memory: for open tables, JOINs, derived
- tables, etc. Let's save a snapshot of current parse tree to the
- statement and restore original THD. In cases when some tree
- transformation can be reused on execute, we set again thd->mem_root from
- stmt->mem_root (see setup_wild for one place where we do that).
- */
- thd->restore_backup_item_arena(stmt, &thd->stmt_backup);
- if (!error)
- error= send_prepare_results(stmt, test(name));
- /* restore to WAIT_PRIOR: QUERY_PRIOR is set inside alloc_query */
- if (!(specialflag & SPECIAL_NO_PRIOR))
- my_pthread_setprio(pthread_self(),WAIT_PRIOR);
- lex_end(lex);
- thd->restore_backup_statement(stmt, &thd->stmt_backup);
- cleanup_items(stmt->free_list);
- close_thread_tables(thd);
- free_items(thd->free_list);
- thd->rollback_item_tree_changes();
- thd->free_list= 0;
- thd->current_arena= thd;
- if (error)
- {
- /* Statement map deletes statement on erase */
- thd->stmt_map.erase(stmt);
- stmt= NULL;
- if (thd->net.report_error)
- send_error(thd);
- /* otherwise the error is sent inside yyparse/send_prepare_results */
- }
- else
- {
- stmt->setup_set_params();
- SELECT_LEX *sl= stmt->lex->all_selects_list;
- for (; sl; sl= sl->next_select_in_list())
- {
- /*
- Save WHERE clause pointers, because they may be changed
- during query optimisation.
- */
- sl->prep_where= sl->where;
- /*
- Switch off a temporary flag that prevents evaluation of
- subqueries in statement prepare.
- */
- sl->uncacheable&= ~UNCACHEABLE_PREPARE;
- }
- stmt->state= Item_arena::PREPARED;
- }
- DBUG_RETURN(!stmt);
- }
- /* Reinit statement before execution */
- static void reset_stmt_for_execute(Prepared_statement *stmt)
- {
- THD *thd= stmt->thd;
- LEX *lex= stmt->lex;
- SELECT_LEX *sl= lex->all_selects_list;
- for (; sl; sl= sl->next_select_in_list())
- {
- /* remove option which was put by mysql_explain_union() */
- sl->options&= ~SELECT_DESCRIBE;
- /*
- Copy WHERE clause pointers to avoid damaging they by optimisation
- */
- if (sl->prep_where)
- {
- sl->where= sl->prep_where->copy_andor_structure(thd);
- sl->where->cleanup();
- }
- DBUG_ASSERT(sl->join == 0);
- ORDER *order;
- /* Fix GROUP list */
- for (order= (ORDER *)sl->group_list.first; order; order= order->next)
- order->item= &order->item_ptr;
- /* Fix ORDER list */
- for (order= (ORDER *)sl->order_list.first; order; order= order->next)
- order->item= &order->item_ptr;
- /*
- TODO: When the new table structure is ready, then have a status bit
- to indicate the table is altered, and re-do the setup_*
- and open the tables back.
- */
- for (TABLE_LIST *tables= (TABLE_LIST*) sl->table_list.first;
- tables;
- tables= tables->next)
- {
- /*
- Reset old pointers to TABLEs: they are not valid since the tables
- were closed in the end of previous prepare or execute call.
- */
- tables->table= 0;
- tables->table_list= 0;
- }
-
- {
- SELECT_LEX_UNIT *unit= sl->master_unit();
- unit->unclean();
- unit->types.empty();
- /* for derived tables & PS (which can't be reset by Item_subquery) */
- unit->reinit_exec_mechanism();
- }
- }
- lex->current_select= &lex->select_lex;
- if (lex->result)
- lex->result->cleanup();
- }
- /*
- Clears parameters from data left from previous execution or long data
-
- SYNOPSIS
- reset_stmt_params()
- stmt - prepared statement for which parameters should be reset
- */
- static void reset_stmt_params(Prepared_statement *stmt)
- {
- Item_param **item= stmt->param_array;
- Item_param **end= item + stmt->param_count;
- for (;item < end ; ++item)
- (**item).reset();
- }
- /*
- Executes previously prepared query.
- If there is any parameters, then replace markers with the data supplied
- from client, and then execute the query.
- SYNOPSIS
- mysql_stmt_execute()
- thd Current thread
- packet Query string
- packet_length Query string length, including terminator character.
- */
- void mysql_stmt_execute(THD *thd, char *packet, uint packet_length)
- {
- ulong stmt_id= uint4korr(packet);
- /*
- Query text for binary log, or empty string if the query is not put into
- binary log.
- */
- String expanded_query;
- #ifndef EMBEDDED_LIBRARY
- uchar *packet_end= (uchar *) packet + packet_length - 1;
- #endif
- Prepared_statement *stmt;
- DBUG_ENTER("mysql_stmt_execute");
- packet+= 9; /* stmt_id + 5 bytes of flags */
- statistic_increment(com_stmt_execute, &LOCK_status);
- if (!(stmt= find_prepared_statement(thd, stmt_id, "mysql_stmt_execute",
- SEND_ERROR)))
- DBUG_VOID_RETURN;
- DBUG_PRINT("exec_query:", ("%s", stmt->query));
- /* Check if we got an error when sending long data */
- if (stmt->state == Item_arena::ERROR)
- {
- send_error(thd, stmt->last_errno, stmt->last_error);
- DBUG_VOID_RETURN;
- }
- DBUG_ASSERT(thd->free_list == NULL);
- mysql_reset_thd_for_next_command(thd);
- #ifndef EMBEDDED_LIBRARY
- if (stmt->param_count)
- {
- uchar *null_array= (uchar *) packet;
- if (setup_conversion_functions(stmt, (uchar **) &packet, packet_end) ||
- stmt->set_params(stmt, null_array, (uchar *) packet, packet_end,
- &expanded_query))
- goto set_params_data_err;
- }
- #else
- /*
- In embedded library we re-install conversion routines each time
- we set params, and also we don't need to parse packet.
- So we do it in one function.
- */
- if (stmt->param_count && stmt->set_params_data(stmt, &expanded_query))
- goto set_params_data_err;
- #endif
- thd->protocol= &thd->protocol_prep; // Switch to binary protocol
- execute_stmt(thd, stmt, &expanded_query, TRUE);
- thd->protocol= &thd->protocol_simple; // Use normal protocol
- DBUG_VOID_RETURN;
- set_params_data_err:
- reset_stmt_params(stmt);
- my_error(ER_WRONG_ARGUMENTS, MYF(0), "mysql_stmt_execute");
- send_error(thd);
- DBUG_VOID_RETURN;
- }
- /*
- Execute prepared statement using parameter values from
- lex->prepared_stmt_params and send result to the client using text protocol.
- */
- void mysql_sql_stmt_execute(THD *thd, LEX_STRING *stmt_name)
- {
- Prepared_statement *stmt;
- /*
- Query text for binary log, or empty string if the query is not put into
- binary log.
- */
- String expanded_query;
- DBUG_ENTER("mysql_sql_stmt_execute");
- /* See comment for statistics_increment in mysql_stmt_prepare */
- statistic_increment(com_stmt_execute, &LOCK_status);
- if (!(stmt= (Prepared_statement*)thd->stmt_map.find_by_name(stmt_name)))
- {
- my_error(ER_UNKNOWN_STMT_HANDLER, MYF(0), stmt_name->length,
- stmt_name->str, "EXECUTE");
- send_error(thd);
- DBUG_VOID_RETURN;
- }
- if (stmt->param_count != thd->lex->prepared_stmt_params.elements)
- {
- my_error(ER_WRONG_ARGUMENTS, MYF(0), "EXECUTE");
- send_error(thd);
- DBUG_VOID_RETURN;
- }
- DBUG_ASSERT(thd->free_list == NULL);
- /* Must go before setting variables, as it clears thd->user_var_events */
- mysql_reset_thd_for_next_command(thd);
- thd->set_n_backup_statement(stmt, &thd->stmt_backup);
- if (stmt->set_params_from_vars(stmt,
- thd->stmt_backup.lex->prepared_stmt_params,
- &expanded_query))
- {
- my_error(ER_WRONG_ARGUMENTS, MYF(0), "EXECUTE");
- send_error(thd);
- }
- thd->command= COM_EXECUTE; /* For nice messages in general log */
- execute_stmt(thd, stmt, &expanded_query, FALSE);
- DBUG_VOID_RETURN;
- }
- /*
- Execute prepared statement.
- SYNOPSIS
- execute_stmt()
- thd Current thread
- stmt Statement to execute
- expanded_query If binary log is enabled, query string with parameter
- placeholders replaced with actual values. Otherwise empty
- string.
- NOTES
- Caller must set parameter values and thd::protocol.
- thd->free_list is assumed to be garbage.
- */
- static void execute_stmt(THD *thd, Prepared_statement *stmt,
- String *expanded_query, bool set_context)
- {
- DBUG_ENTER("execute_stmt");
- if (set_context)
- thd->set_n_backup_statement(stmt, &thd->stmt_backup);
- reset_stmt_for_execute(stmt);
- if (expanded_query->length() &&
- alloc_query(thd, (char *)expanded_query->ptr(),
- expanded_query->length()+1))
- {
- my_error(ER_OUTOFMEMORY, 0, expanded_query->length());
- DBUG_VOID_RETURN;
- }
- mysql_log.write(thd, thd->command, "[%lu] %s", stmt->id, thd->query);
- /*
- At first execution of prepared statement we will perform logical
- transformations of the query tree (i.e. negations elimination).
- This should be done permanently on the parse tree of this statement.
- */
- thd->current_arena= stmt;
- if (!(specialflag & SPECIAL_NO_PRIOR))
- my_pthread_setprio(pthread_self(),QUERY_PRIOR);
- mysql_execute_command(thd);
- thd->lex->unit.cleanup();
- if (!(specialflag & SPECIAL_NO_PRIOR))
- my_pthread_setprio(pthread_self(), WAIT_PRIOR);
- /*
- 'start_time' is set in dispatch_command, but THD::query will
- be freed when we return from this function. So let's log the slow
- query here.
- */
- log_slow_statement(thd);
- /* Prevent from second logging in the end of dispatch_command */
- thd->enable_slow_log= FALSE;
- /* Free Items that were created during this execution of the PS. */
- free_items(thd->free_list);
- thd->free_list= 0;
- if (stmt->state == Item_arena::PREPARED)
- stmt->state= Item_arena::EXECUTED;
- thd->current_arena= thd;
- cleanup_items(stmt->free_list);
- thd->rollback_item_tree_changes();
- reset_stmt_params(stmt);
- close_thread_tables(thd); // to close derived tables
- thd->set_statement(&thd->stmt_backup);
- DBUG_VOID_RETURN;
- }
- /*
- Reset a prepared statement in case there was a recoverable error.
- SYNOPSIS
- mysql_stmt_reset()
- thd Thread handle
- packet Packet with stmt id
- DESCRIPTION
- This function resets statement to the state it was right after prepare.
- It can be used to:
- - clear an error happened during mysql_stmt_send_long_data
- - cancel long data stream for all placeholders without
- having to call mysql_stmt_execute.
- Sends 'OK' packet in case of success (statement was reset)
- or 'ERROR' packet (unrecoverable error/statement not found/etc).
- */
- void mysql_stmt_reset(THD *thd, char *packet)
- {
- /* There is always space for 4 bytes in buffer */
- ulong stmt_id= uint4korr(packet);
- Prepared_statement *stmt;
-
- DBUG_ENTER("mysql_stmt_reset");
- statistic_increment(com_stmt_reset, &LOCK_status);
- if (!(stmt= find_prepared_statement(thd, stmt_id, "mysql_stmt_reset",
- SEND_ERROR)))
- DBUG_VOID_RETURN;
- stmt->state= Item_arena::PREPARED;
- /*
- Clear parameters from data which could be set by
- mysql_stmt_send_long_data() call.
- */
- reset_stmt_params(stmt);
- mysql_reset_thd_for_next_command(thd);
- send_ok(thd);
-
- DBUG_VOID_RETURN;
- }
- /*
- Delete a prepared statement from memory.
- Note: we don't send any reply to that command.
- */
- void mysql_stmt_free(THD *thd, char *packet)
- {
- /* There is always space for 4 bytes in packet buffer */
- ulong stmt_id= uint4korr(packet);
- Prepared_statement *stmt;
- DBUG_ENTER("mysql_stmt_free");
- statistic_increment(com_stmt_close, &LOCK_status);
- if (!(stmt= find_prepared_statement(thd, stmt_id, "mysql_stmt_close",
- DONT_SEND_ERROR)))
- DBUG_VOID_RETURN;
- /* Statement map deletes statement on erase */
- thd->stmt_map.erase(stmt);
- DBUG_VOID_RETURN;
- }
- /*
- Long data in pieces from client
- SYNOPSIS
- mysql_stmt_get_longdata()
- thd Thread handle
- pos String to append
- packet_length Length of string
- DESCRIPTION
- Get a part of a long data.
- To make the protocol efficient, we are not sending any return packages
- here.
- If something goes wrong, then we will send the error on 'execute'
- We assume that the client takes care of checking that all parts are sent
- to the server. (No checking that we get a 'end of column' in the server)
- */
- void mysql_stmt_get_longdata(THD *thd, char *packet, ulong packet_length)
- {
- ulong stmt_id;
- uint param_number;
- Prepared_statement *stmt;
- Item_param *param;
- char *packet_end= packet + packet_length - 1;
-
- DBUG_ENTER("mysql_stmt_get_longdata");
- statistic_increment(com_stmt_send_long_data, &LOCK_status);
- #ifndef EMBEDDED_LIBRARY
- /* Minimal size of long data packet is 6 bytes */
- if ((ulong) (packet_end - packet) < MYSQL_LONG_DATA_HEADER)
- {
- my_error(ER_WRONG_ARGUMENTS, MYF(0), "mysql_stmt_send_long_data");
- DBUG_VOID_RETURN;
- }
- #endif
- stmt_id= uint4korr(packet);
- packet+= 4;
- if (!(stmt=find_prepared_statement(thd, stmt_id, "mysql_stmt_send_long_data",
- DONT_SEND_ERROR)))
- DBUG_VOID_RETURN;
- param_number= uint2korr(packet);
- packet+= 2;
- #ifndef EMBEDDED_LIBRARY
- if (param_number >= stmt->param_count)
- {
- /* Error will be sent in execute call */
- stmt->state= Item_arena::ERROR;
- stmt->last_errno= ER_WRONG_ARGUMENTS;
- sprintf(stmt->last_error, ER(ER_WRONG_ARGUMENTS),
- "mysql_stmt_send_long_data");
- DBUG_VOID_RETURN;
- }
- #endif
- param= stmt->param_array[param_number];
- #ifndef EMBEDDED_LIBRARY
- if (param->set_longdata(packet, (ulong) (packet_end - packet)))
- #else
- if (param->set_longdata(thd->extra_data, thd->extra_length))
- #endif
- {
- stmt->state= Item_arena::ERROR;
- stmt->last_errno= ER_OUTOFMEMORY;
- sprintf(stmt->last_error, ER(ER_OUTOFMEMORY), 0);
- }
- DBUG_VOID_RETURN;
- }
- Prepared_statement::Prepared_statement(THD *thd_arg)
- :Statement(thd_arg),
- thd(thd_arg),
- param_array(0),
- param_count(0),
- last_errno(0)
- {
- *last_error= ' ';
- }
- void Prepared_statement::setup_set_params()
- {
- /* Setup binary logging */
- if (mysql_bin_log.is_open() && is_update_query(lex->sql_command) ||
- mysql_log.is_open() || mysql_slow_log.is_open())
- {
- set_params_from_vars= insert_params_from_vars_with_log;
- #ifndef EMBEDDED_LIBRARY
- set_params= insert_params_withlog;
- #else
- set_params_data= emb_insert_params_withlog;
- #endif
- }
- else
- {
- set_params_from_vars= insert_params_from_vars;
- #ifndef EMBEDDED_LIBRARY
- set_params= insert_params;
- #else
- set_params_data= emb_insert_params;
- #endif
- }
- }
- Prepared_statement::~Prepared_statement()
- {
- free_items(free_list);
- delete lex->result;
- }
- Item_arena::Type Prepared_statement::type() const
- {
- return PREPARED_STATEMENT;
- }