/* 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][type:2][data] - Checks if the type is specified by client, and if yes reads the type, and stores the data in that format. - 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_acl.h" #include "sql_select.h" // for JOIN #include // for isspace() #ifdef EMBEDDED_LIBRARY /* include MYSQL_BIND headers */ #include #endif const String my_null_string("NULL", 4, default_charset_info); /****************************************************************************** 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]; bool get_longdata_error; bool long_data_used; bool log_full_query; #ifndef EMBEDDED_LIBRARY bool (*set_params)(Prepared_statement *st, uchar *data, uchar *data_end, uchar *read_pos); #else bool (*set_params_data)(Prepared_statement *st); #endif bool (*set_params_from_vars)(Prepared_statement *stmt, List& varnames); public: Prepared_statement(THD *thd_arg); virtual ~Prepared_statement(); virtual Statement::Type type() const; }; /****************************************************************************** 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() != Statement::PREPARED_STATEMENT) { my_error(ER_UNKNOWN_STMT_HANDLER, MYF(0), id, 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]; 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 to List */ return my_net_write(net, buff, sizeof(buff)) || (stmt->param_count && stmt->thd->protocol_simple.send_fields((List *) &stmt->lex->param_list, 0)) || net_flush(net); return 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 /* TODO: why uint4korr here? (should be uint8korr) */ 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 */ void set_param_tiny(Item_param *param, uchar **pos, ulong len) { #ifndef EMBEDDED_LIBRARY if (len < 1) return; #endif param->set_int((longlong)(**pos)); *pos+= 1; } void set_param_short(Item_param *param, uchar **pos, ulong len) { #ifndef EMBEDDED_LIBRARY if (len < 2) return; #endif param->set_int((longlong)sint2korr(*pos)); *pos+= 2; } void set_param_int32(Item_param *param, uchar **pos, ulong len) { #ifndef EMBEDDED_LIBRARY if (len < 4) return; #endif param->set_int((longlong)sint4korr(*pos)); *pos+= 4; } void set_param_int64(Item_param *param, uchar **pos, ulong len) { #ifndef EMBEDDED_LIBRARY if (len < 8) return; #endif param->set_int((longlong)sint8korr(*pos)); *pos+= 8; } void set_param_float(Item_param *param, uchar **pos, ulong len) { #ifndef EMBEDDED_LIBRARY if (len < 4) return; #endif float data; float4get(data,*pos); param->set_double((double) data); *pos+= 4; } void set_param_double(Item_param *param, uchar **pos, ulong len) { #ifndef EMBEDDED_LIBRARY if (len < 8) return; #endif double data; float8get(data,*pos); param->set_double((double) data); *pos+= 8; } void set_param_time(Item_param *param, uchar **pos, ulong len) { ulong length; if ((length= get_param_length(pos, len)) >= 8) { uchar *to= *pos; TIME tm; /* TODO: why length is compared with 8 here? */ tm.second_part= (length > 8 ) ? (ulong) sint4korr(to+7): 0; tm.day= (ulong) sint4korr(to+1); tm.hour= (uint) to[5]; tm.minute= (uint) to[6]; tm.second= (uint) to[7]; tm.year= tm.month= 0; tm.neg= (bool)to[0]; param->set_time(&tm, TIMESTAMP_TIME); } *pos+= length; } void set_param_datetime(Item_param *param, uchar **pos, ulong len) { uint length; if ((length= get_param_length(pos, len)) >= 4) { uchar *to= *pos; TIME tm; tm.second_part= (length > 7 ) ? (ulong) sint4korr(to+7): 0; 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.year= (uint) sint2korr(to); tm.month= (uint) to[2]; tm.day= (uint) to[3]; tm.neg= 0; param->set_time(&tm, TIMESTAMP_DATETIME); } *pos+= length; } void set_param_date(Item_param *param, uchar **pos, ulong len) { ulong length; if ((length= get_param_length(pos, len)) >= 4) { uchar *to= *pos; TIME tm; 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; param->set_time(&tm, TIMESTAMP_DATE); } *pos+= length; } void set_param_str(Item_param *param, uchar **pos, ulong len) { ulong length= get_param_length(pos, len); param->set_value((const char *)*pos, length); *pos+= length; } static void setup_one_conversion_function(Item_param *param, uchar param_type) { switch (param_type) { case FIELD_TYPE_TINY: param->set_param_func= set_param_tiny; param->item_result_type= INT_RESULT; break; case FIELD_TYPE_SHORT: param->set_param_func= set_param_short; param->item_result_type= INT_RESULT; break; case FIELD_TYPE_LONG: param->set_param_func= set_param_int32; param->item_result_type= INT_RESULT; break; case FIELD_TYPE_LONGLONG: param->set_param_func= set_param_int64; param->item_result_type= INT_RESULT; break; case FIELD_TYPE_FLOAT: param->set_param_func= set_param_float; param->item_result_type= REAL_RESULT; break; case FIELD_TYPE_DOUBLE: param->set_param_func= set_param_double; param->item_result_type= REAL_RESULT; break; case FIELD_TYPE_TIME: param->set_param_func= set_param_time; param->item_result_type= STRING_RESULT; break; case FIELD_TYPE_DATE: param->set_param_func= set_param_date; param->item_result_type= STRING_RESULT; break; case MYSQL_TYPE_DATETIME: case MYSQL_TYPE_TIMESTAMP: param->set_param_func= set_param_datetime; param->item_result_type= STRING_RESULT; break; default: param->set_param_func= set_param_str; param->item_result_type= STRING_RESULT; } } #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) { THD *thd= stmt->thd; Item_param **begin= stmt->param_array; Item_param **end= begin + stmt->param_count; uint32 length= 0; String str, query; 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->long_data_supplied) res= param->query_val_str(&str); else { if (is_param_null(null_array, it - begin)) { param->maybe_null= param->null_value= 1; res= &my_null_string; } else { param->maybe_null= param->null_value= 0; 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 (query.replace(param->pos_in_query+length, 1, *res)) DBUG_RETURN(1); length+= res->length()-1; } if (alloc_query(thd, (char *)query.ptr(), query.length()+1)) DBUG_RETURN(1); DBUG_RETURN(0); } static bool insert_params(Prepared_statement *stmt, uchar *null_array, uchar *read_pos, uchar *data_end) { 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->long_data_supplied) { if (is_param_null(null_array, it - begin)) param->maybe_null= param->null_value= 1; else { param->maybe_null= param->null_value= 0; if (read_pos >= data_end) DBUG_RETURN(1); param->set_param_func(param, &read_pos, data_end - read_pos); } } } 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; for (; it < end; ++it) { if (read_pos >= data_end) DBUG_RETURN(1); setup_one_conversion_function(*it, *read_pos); read_pos+= 2; } } *data= read_pos; DBUG_RETURN(0); } #else static bool emb_insert_params(Prepared_statement *stmt) { 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(param, client_param->buffer_type); if (!param->long_data_supplied) { if (*client_param->is_null) param->maybe_null= param->null_value= 1; else { uchar *buff= (uchar*)client_param->buffer; param->maybe_null= param->null_value= 0; param->set_param_func(param, &buff, client_param->length ? *client_param->length : client_param->buffer_length); } } } DBUG_RETURN(0); } static bool emb_insert_params_withlog(Prepared_statement *stmt) { 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, query; 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(param, client_param->buffer_type); if (param->long_data_supplied) res= param->query_val_str(&str); else { if (*client_param->is_null) { param->maybe_null= param->null_value= 1; res= &my_null_string; } else { uchar *buff= (uchar*)client_param->buffer; param->maybe_null= param->null_value= 0; param->set_param_func(param, &buff, client_param->length ? *client_param->length : client_param->buffer_length); res= param->query_val_str(&str); } } if (query.replace(param->pos_in_query+length, 1, *res)) DBUG_RETURN(1); length+= res->length()-1; } if (alloc_query(thd, (char *) query.ptr(), query.length()+1)) DBUG_RETURN(1); DBUG_RETURN(0); } #endif /*!EMBEDDED_LIBRARY*/ /* Set prepared statement parameters from user variables. Also replace '?' marks with values in thd->query if binary logging is on. 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 */ static bool insert_params_from_vars(Prepared_statement *stmt, List& varnames) { 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 var_it(varnames); for (Item_param **it= begin; it < end; ++it) { Item_param *param= *it; varname= var_it++; if ((entry= (user_var_entry*)hash_search(&stmt->thd->user_vars, (byte*) varname->str, varname->length)) && entry->value) { param->item_result_type= entry->type; switch (entry->type) { case REAL_RESULT: param->set_double(*(double*)entry->value); break; case INT_RESULT: param->set_int(*(longlong*)entry->value); break; case STRING_RESULT: param->set_value(entry->value, entry->length, entry->collation.collation); break; default: DBUG_ASSERT(0); } } else { param->item_result_type= INT_RESULT; param->maybe_null= param->null_value= 1; param->value_is_set= 0; } } DBUG_RETURN(0); } static bool insert_params_from_vars_with_log(Prepared_statement *stmt, List& varnames) { 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 var_it(varnames); String str, query; const String *res; uint32 length= 0; for (Item_param **it= begin; it < end; ++it) { Item_param *param= *it; varname= var_it++; if ((entry= (user_var_entry*)hash_search(&stmt->thd->user_vars, (byte*) varname->str, varname->length)) && entry->value) { param->item_result_type= entry->type; switch (entry->type) { case REAL_RESULT: param->set_double(*(double*)entry->value); break; case INT_RESULT: param->set_int(*(longlong*)entry->value); break; case STRING_RESULT: param->set_value(entry->value, entry->length, entry->collation.collation); break; default: DBUG_ASSERT(0); } res= param->query_val_str(&str); } else { param->item_result_type= INT_RESULT; param->maybe_null= param->null_value= 1; param->value_is_set= 0; res= &my_null_string; } if (query.replace(param->pos_in_query+length, 1, *res)) DBUG_RETURN(1); length+= res->length()-1; } if (alloc_query(stmt->thd, (char *) query.ptr(), query.length()+1)) DBUG_RETURN(1); DBUG_RETURN(0); } /* Validate the following information for INSERT statement: - field existence - fields count SYNOPSIS mysql_test_insert_fields() RETURN VALUE 0 ok 1 error, sent to the client -1 error, not sent to client */ static int mysql_test_insert_fields(Prepared_statement *stmt, TABLE_LIST *table_list, List &fields, List &values_list) { THD *thd= stmt->thd; TABLE *table; List_iterator_fast its(values_list); List_item *values; DBUG_ENTER("mysql_test_insert_fields"); #ifndef NO_EMBEDDED_ACCESS_CHECKS my_bool update=(stmt->lex->value_list.elements ? UPDATE_ACL : 0); ulong privilege= (stmt->lex->duplicates == DUP_REPLACE ? INSERT_ACL | DELETE_ACL : INSERT_ACL | update); if (check_access(thd,privilege,table_list->db, &table_list->grant.privilege,0,0) || (grant_option && check_grant(thd,privilege,table_list,0,0))) DBUG_RETURN(1); #endif /* open temporary memory pool for temporary data allocated by derived tables & preparation procedure */ thd->allocate_temporary_memory_pool_for_ps_preparing(); if (open_and_lock_tables(thd, table_list)) { thd->free_temporary_memory_pool_for_ps_preparing(); DBUG_RETURN(-1); } table= table_list->table; if ((values= its++)) { uint value_count; ulong counter= 0; if (check_insert_fields(thd,table,fields,*values,1)) { thd->free_temporary_memory_pool_for_ps_preparing(); DBUG_RETURN(-1); } thd->free_temporary_memory_pool_for_ps_preparing(); 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); DBUG_RETURN(-1); } } } else { thd->free_temporary_memory_pool_for_ps_preparing(); } DBUG_RETURN(0); } /* Validate the following information: UPDATE - set and where clause DELETE - where clause SYNOPSIS mysql_test_upd_fields() RETURN VALUE 0 success 1 error, sent to client -1 error, not sent to client */ static int mysql_test_upd_fields(Prepared_statement *stmt, TABLE_LIST *table_list, List &fields, List &values, COND *conds) { THD *thd= stmt->thd; DBUG_ENTER("mysql_test_upd_fields"); #ifndef NO_EMBEDDED_ACCESS_CHECKS if (check_access(thd,UPDATE_ACL,table_list->db, &table_list->grant.privilege,0,0) || (grant_option && check_grant(thd,UPDATE_ACL,table_list,0,0))) DBUG_RETURN(1); #endif /* open temporary memory pool for temporary data allocated by derived tables & preparation procedure */ thd->allocate_temporary_memory_pool_for_ps_preparing(); if (open_and_lock_tables(thd, table_list)) goto err; if (setup_tables(table_list) || setup_fields(thd, 0, table_list, fields, 1, 0, 0) || setup_conds(thd, table_list, &conds) || thd->net.report_error) goto err; thd->free_temporary_memory_pool_for_ps_preparing(); /* TODO: here we should send types of placeholders to the client. */ DBUG_RETURN(0); err: thd->free_temporary_memory_pool_for_ps_preparing(); DBUG_RETURN(-1); } /* Validate the following information: SELECT - column list - where clause - order clause - having clause - group by clause - if no column spec i.e. '*', then setup all fields In case of success, if this query is not EXPLAIN, send column list info back to client. SYNOPSIS mysql_test_select_fields() RETURN VALUE 0 success 1 error, sent to client -1 error, not sent to client */ static int mysql_test_select_fields(Prepared_statement *stmt, TABLE_LIST *tables, uint wild_num, List &fields, COND *conds, uint og_num, ORDER *order, ORDER *group, Item *having, ORDER *proc, ulong select_options, SELECT_LEX_UNIT *unit, SELECT_LEX *select_lex, bool text_protocol) { THD *thd= stmt->thd; LEX *lex= stmt->lex; DBUG_ENTER("mysql_test_select_fields"); #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*",0,0,0)) DBUG_RETURN(1); #endif if ((&lex->select_lex != lex->all_selects_list && lex->unit.create_total_list(thd, lex, &tables))) DBUG_RETURN(1); /* open temporary memory pool for temporary data allocated by derived tables & preparation procedure */ thd->allocate_temporary_memory_pool_for_ps_preparing(); if (open_and_lock_tables(thd, tables)) { send_error(thd); goto err; } if (lex->describe) { if (!text_protocol && send_prep_stmt(stmt, 0)) goto err; } else { select_result *result= lex->result; if (!result && !(result= new select_send())) { send_error(thd, ER_OUT_OF_RESOURCES); goto err; } thd->used_tables= 0; // Updated by setup_fields if (unit->prepare(thd, result, 0)) { send_error(thd); goto err_prep; } if (!text_protocol) { if (send_prep_stmt(stmt, fields.elements) || thd->protocol_simple.send_fields(&fields, 0) #ifndef EMBEDDED_LIBRARY || net_flush(&thd->net) #endif ) goto err_prep; } unit->cleanup(); } thd->free_temporary_memory_pool_for_ps_preparing(); DBUG_RETURN(0); err_prep: unit->cleanup(); err: thd->free_temporary_memory_pool_for_ps_preparing(); DBUG_RETURN(1); } /* 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; DBUG_ENTER("send_prepare_results"); DBUG_PRINT("enter",("command: %d, param_count: %ld", sql_command, stmt->param_count)); switch (sql_command) { case SQLCOM_INSERT: if ((res= mysql_test_insert_fields(stmt, tables, lex->field_list, lex->many_values))) goto error; break; case SQLCOM_UPDATE: /* XXX: fallthrough */ case SQLCOM_DELETE: if ((res= mysql_test_upd_fields(stmt, tables, select_lex->item_list, lex->value_list, select_lex->where))) goto error; break; case SQLCOM_SELECT: if ((res= mysql_test_select_fields(stmt, tables, select_lex->with_wild, select_lex->item_list, select_lex->where, select_lex->order_list.elements + select_lex->group_list.elements, (ORDER*) select_lex->order_list.first, (ORDER*) select_lex->group_list.first, select_lex->having, (ORDER*)lex->proc_list.first, select_lex->options | thd->options, &(lex->unit), select_lex, text_protocol))) goto error; /* Statement and field info has already been sent */ DBUG_RETURN(0); default: /* Rest fall through to default category, no parsing for non-DML statements */ break; } DBUG_RETURN(text_protocol? 0: send_prep_stmt(stmt, 0)); error: if (res < 0) send_error(thd, thd->killed ? ER_SERVER_SHUTDOWN : 0); DBUG_RETURN(1); } /* Initialize array of parametes in statement from LEX. (We need to have quick access to items by number in mysql_send_longdata). This is to avoid using malloc/realloc in the parser. */ static bool init_param_array(Prepared_statement *stmt) { LEX *lex= stmt->lex; if ((stmt->param_count= lex->param_list.elements)) { Item_param **to; List_iterator 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(stmt->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; } /* Parse the query and send 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 will allow 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. */ Prepared_statement *mysql_stmt_prepare(THD *thd, char *packet, uint packet_length, bool text_protocol) { LEX *lex; Prepared_statement *stmt= new Prepared_statement(thd); int error; DBUG_ENTER("mysql_stmt_prepare"); if (stmt == 0) { send_error(thd, ER_OUT_OF_RESOURCES); DBUG_RETURN(NULL); } if (thd->stmt_map.insert(stmt)) { delete stmt; send_error(thd, ER_OUT_OF_RESOURCES); DBUG_RETURN(NULL); } thd->stmt_backup.set_statement(thd); thd->stmt_backup.set_item_arena(thd); thd->set_statement(stmt); thd->set_item_arena(stmt); if (alloc_query(thd, packet, packet_length)) { stmt->set_statement(thd); stmt->set_item_arena(thd); thd->set_statement(&thd->stmt_backup); thd->set_item_arena(&thd->stmt_backup); /* Statement map deletes statement on erase */ thd->stmt_map.erase(stmt); send_error(thd, ER_OUT_OF_RESOURCES); DBUG_RETURN(NULL); } mysql_log.write(thd, COM_PREPARE, "%s", packet); thd->current_statement= stmt; lex= lex_start(thd, (uchar *) thd->query, thd->query_length); mysql_init_query(thd); lex->safe_to_cache_query= 0; error= yyparse((void *)thd) || thd->is_fatal_error || init_param_array(stmt) || send_prepare_results(stmt, text_protocol); /* 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); stmt->set_statement(thd); stmt->set_item_arena(thd); thd->set_statement(&thd->stmt_backup); thd->set_item_arena(&thd->stmt_backup); thd->current_statement= 0; if (error) { /* Statement map deletes statement on erase */ thd->stmt_map.erase(stmt); stmt= NULL; /* error is sent inside yyparse/send_prepare_results */ } else { SELECT_LEX *sl= stmt->lex->all_selects_list; /* Save WHERE clause pointers, because they may be changed during query optimisation. */ for (; sl; sl= sl->next_select_in_list()) { sl->prep_where= sl->where; } } DBUG_RETURN(stmt); } /* Reinit statement before execution */ static void reset_stmt_for_execute(Prepared_statement *stmt) { THD *thd= stmt->thd; SELECT_LEX *sl= stmt->lex->all_selects_list; for (; sl; sl= sl->next_select_in_list()) { /* Copy WHERE clause pointers to avoid damaging they by optimisation */ if (sl->prep_where) sl->where= sl->prep_where->copy_andor_structure(thd); DBUG_ASSERT(sl->join == 0); ORDER *order; /* Fix GROUP list */ for (order=(ORDER *)sl->group_list.first ; order ; order=order->next) order->item= (Item **)(order+1); /* Fix ORDER list */ for (order=(ORDER *)sl->order_list.first ; order ; order=order->next) order->item= (Item **)(order+1); /* 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(); } } } /* Executes previously prepared query. If there is any parameters, then replace markers with the data supplied from client, and then execute the query. SYNOPSYS mysql_stmt_execute() */ void mysql_stmt_execute(THD *thd, char *packet, uint packet_length) { ulong stmt_id= uint4korr(packet); #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 */ if (!(stmt= find_prepared_statement(thd, stmt_id, "execute", SEND_ERROR))) DBUG_VOID_RETURN; /* Check if we got an error when sending long data */ if (stmt->get_longdata_error) { send_error(thd, stmt->last_errno, stmt->last_error); DBUG_VOID_RETURN; } thd->stmt_backup.set_statement(thd); thd->set_statement(stmt); reset_stmt_for_execute(stmt); #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)) 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)) goto set_params_data_err; #endif if (!(specialflag & SPECIAL_NO_PRIOR)) my_pthread_setprio(pthread_self(),QUERY_PRIOR); /* TODO: Also, have checks on basic executions such as mysql_insert(), mysql_delete(), mysql_update() and mysql_select() to not to have re-check on setup_* and other things .. */ thd->protocol= &thd->protocol_prep; // Switch to binary protocol mysql_execute_command(thd); thd->protocol= &thd->protocol_simple; // Use normal protocol if (!(specialflag & SPECIAL_NO_PRIOR)) my_pthread_setprio(pthread_self(), WAIT_PRIOR); cleanup_items(stmt->free_list); close_thread_tables(thd); // to close derived tables thd->set_statement(&thd->stmt_backup); DBUG_VOID_RETURN; set_params_data_err: thd->set_statement(&thd->stmt_backup); my_error(ER_WRONG_ARGUMENTS, MYF(0), "mysql_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, Prepared_statement *stmt) { DBUG_ENTER("mysql_stmt_execute"); if (stmt->param_count != thd->lex->prepared_stmt_params.elements) { my_error(ER_WRONG_ARGUMENTS, MYF(0), "mysql_execute"); send_error(thd); DBUG_VOID_RETURN; } thd->stmt_backup.set_statement(thd); thd->set_statement(stmt); reset_stmt_for_execute(stmt); thd->command= COM_EXECUTE; if (stmt->set_params_from_vars(stmt, thd->stmt_backup.lex-> prepared_stmt_params)) { thd->set_statement(&thd->stmt_backup); my_error(ER_WRONG_ARGUMENTS, MYF(0), "mysql_execute"); send_error(thd); } if (!(specialflag & SPECIAL_NO_PRIOR)) my_pthread_setprio(pthread_self(),QUERY_PRIOR); mysql_execute_command(thd); if (!(specialflag & SPECIAL_NO_PRIOR)) my_pthread_setprio(pthread_self(), WAIT_PRIOR); cleanup_items(stmt->free_list); 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 an error in send_longdata. Note: we don't send any reply to that command. SYNOPSIS mysql_stmt_reset() thd Thread handle packet Packet with stmt id DESCRIPTION This function is useful when one gets an error after calling mysql_stmt_getlongdata() and wants to reset the handle so that one can call execute again. See also bug #1664 */ 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"); if (!(stmt= find_prepared_statement(thd, stmt_id, "reset", DONT_SEND_ERROR))) DBUG_VOID_RETURN; stmt->get_longdata_error= 0; /* Free long data if used */ if (stmt->long_data_used) { Item_param **item= stmt->param_array; Item_param **end= item + stmt->param_count; stmt->long_data_used= 0; for (; item < end ; item++) (**item).reset(); } 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"); if (!(stmt= find_prepared_statement(thd, stmt_id, "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 *pos, ulong packet_length) { Prepared_statement *stmt; DBUG_ENTER("mysql_stmt_get_longdata"); #ifndef EMBEDDED_LIBRARY /* The following should never happen */ if (packet_length < MYSQL_LONG_DATA_HEADER+1) { my_error(ER_WRONG_ARGUMENTS, MYF(0), "get_longdata"); DBUG_VOID_RETURN; } #endif ulong stmt_id= uint4korr(pos); uint param_number= uint2korr(pos+4); if (!(stmt=find_prepared_statement(thd, stmt_id, "get_longdata", DONT_SEND_ERROR))) DBUG_VOID_RETURN; #ifndef EMBEDDED_LIBRARY if (param_number >= stmt->param_count) { /* Error will be sent in execute call */ stmt->get_longdata_error= 1; stmt->last_errno= ER_WRONG_ARGUMENTS; sprintf(stmt->last_error, ER(ER_WRONG_ARGUMENTS), "get_longdata"); DBUG_VOID_RETURN; } pos+= MYSQL_LONG_DATA_HEADER; // Point to data #endif Item_param *param= stmt->param_array[param_number]; #ifndef EMBEDDED_LIBRARY param->set_longdata(pos, packet_length-MYSQL_LONG_DATA_HEADER-1); #else param->set_longdata(thd->extra_data, thd->extra_length); #endif stmt->long_data_used= 1; 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), get_longdata_error(0), long_data_used(0), log_full_query(0) { *last_error= '\0'; if (mysql_bin_log.is_open()) { log_full_query= 1; 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); } Statement::Type Prepared_statement::type() const { return PREPARED_STATEMENT; }