/* 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() #include "sp_head.h" #include "sp.h" #ifdef EMBEDDED_LIBRARY /* include MYSQL_BIND headers */ #include <mysql.h> #else #include <mysql_com.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); /****************************************************************************** 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 }; /* 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) { 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); 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, Protocol::SEND_EOF))); } #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->clear_error(); 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) { #ifndef EMBEDDED_LIBRARY if (len < 4) return; #endif float data; float4get(data,*pos); param->set_double((double) data); *pos+= 4; } static 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; } #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_client= &my_charset_bin; 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_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 str; 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); DBUG_ASSERT(entry); if (param->set_from_user_var(stmt->thd, entry)) DBUG_RETURN(1); /* Insert @'escaped-varname' instead of parameter in the query */ char *buf, *ptr; str.length(0); if (str.reserve(entry->name.length*2+3)) DBUG_RETURN(1); buf= str.c_ptr_quick(); ptr= buf; *ptr++= '@'; *ptr++= '\''; ptr+= escape_string_for_mysql(&my_charset_utf8_general_ci, ptr, entry->name.str, entry->name.length); *ptr++= '\''; str.length(ptr - buf); if (param->convert_str_value(stmt->thd)) DBUG_RETURN(1); /* out of memory */ if (query->replace(param->pos_in_query+length, 1, str)) DBUG_RETURN(1); length+= str.length()-1; } DBUG_RETURN(0); } /* Validate INSERT statement: SYNOPSIS mysql_test_insert() stmt prepared statemen handler tables global/local table list RETURN VALUE FALSE OK TRUE error */ static bool 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; bool res; 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 */ if (open_and_lock_tables(thd, table_list)) { DBUG_RETURN(TRUE); } if ((values= its++)) { uint value_count; ulong counter= 0; Item *unused_conds= 0; if (table_list->table) { // don't allocate insert_values table_list->table->insert_values=(byte *)1; } if ((res= mysql_prepare_insert(thd, table_list, table_list->table, fields, values, update_fields, update_values, duplic, &unused_conds, FALSE))) goto error; value_count= values->elements; its.rewind(); while ((values= its++)) { counter++; if (values->elements != value_count) { my_error(ER_WRONG_VALUE_COUNT_ON_ROW, MYF(0), counter); goto error; } if (setup_fields(thd, 0, table_list, *values, 0, 0, 0)) goto error; } } res= 0; error: lex->unit.cleanup(); /* insert_values is cleared in open_table */ DBUG_RETURN(res); } /* Validate UPDATE statement SYNOPSIS mysql_test_update() stmt prepared statemen handler tables list of tables queries RETURN VALUE 0 success 2 convert to multi_update 1 error */ static int mysql_test_update(Prepared_statement *stmt, TABLE_LIST *table_list) { int res; THD *thd= stmt->thd; uint table_count= 0; SELECT_LEX *select= &stmt->lex->select_lex; DBUG_ENTER("mysql_test_update"); if (update_precheck(thd, table_list)) DBUG_RETURN(1); if (!open_tables(thd, table_list, &table_count)) { if (table_list->ancestor && table_list->ancestor->next_local) { DBUG_ASSERT(table_list->view); DBUG_PRINT("info", ("Switch to multi-update")); /* pass counter value */ thd->lex->table_count= table_count; /* give correct value to multi_lock_option, because it will be used in multiupdate */ thd->lex->multi_lock_option= table_list->lock_type; /* convert to multiupdate */ return 2; } if (lock_tables(thd, table_list, table_count) || mysql_handle_derived(thd->lex, &mysql_derived_prepare) || (thd->fill_derived_tables() && mysql_handle_derived(thd->lex, &mysql_derived_filling))) DBUG_RETURN(1); if (!(res= mysql_prepare_update(thd, table_list, &select->where, select->order_list.elements, (ORDER *) select->order_list.first))) { thd->lex->select_lex.no_wrap_view_item= 1; if (setup_fields(thd, 0, table_list, select->item_list, 1, 0, 0)) { res= 1; thd->lex->select_lex.no_wrap_view_item= 0; } else { thd->lex->select_lex.no_wrap_view_item= 0; if (setup_fields(thd, 0, table_list, stmt->lex->value_list, 0, 0, 0)) res= 1; } } stmt->lex->unit.cleanup(); } else res= 1; /* 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 FALSE success TRUE error */ static int mysql_test_delete(Prepared_statement *stmt, TABLE_LIST *table_list) { THD *thd= stmt->thd; LEX *lex= stmt->lex; DBUG_ENTER("mysql_test_delete"); if (delete_precheck(thd, table_list)) DBUG_RETURN(TRUE); if (!open_and_lock_tables(thd, table_list)) { bool res; if (!table_list->table) { DBUG_ASSERT(table_list->view && table_list->ancestor && table_list->ancestor->next_local); my_error(ER_VIEW_DELETE_MERGE_VIEW, MYF(0), table_list->view_db.str, table_list->view_name.str); DBUG_RETURN(-1); } res= mysql_prepare_delete(thd, table_list, &lex->select_lex.where); lex->unit.cleanup(); DBUG_RETURN(res); } /* TODO: here we should send types of placeholders to the client. */ DBUG_RETURN(TRUE); } /* 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 FALSE success TRUE error, 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; bool result; 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(TRUE); } else if (check_access(thd, privilege, any_db,0,0,0)) DBUG_RETURN(TRUE); #endif result= TRUE; if (!lex->result && !(lex->result= new (stmt->mem_root) select_send)) goto err; if (open_and_lock_tables(thd, tables)) goto err; thd->used_tables= 0; // Updated by setup_fields /* JOIN::prepare calls It is not SELECT COMMAND for sure, so setup_tables will be called as usual, and we pass 0 as setup_tables_done_option */ if (unit->prepare(thd, 0, 0)) { 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, Protocol::SEND_EOF) || thd->protocol->flush()) goto err_prep; } } result= FALSE; // 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 FALSE success TRUE error, sent to client */ static bool mysql_test_do_fields(Prepared_statement *stmt, TABLE_LIST *tables, List<Item> *values) { DBUG_ENTER("mysql_test_do_fields"); THD *thd= stmt->thd; bool res; if (tables && check_table_access(thd, SELECT_ACL, tables, 0)) DBUG_RETURN(TRUE); if (tables && open_and_lock_tables(thd, tables)) { DBUG_RETURN(TRUE); } res= setup_fields(thd, 0, 0, *values, 0, 0, 0); stmt->lex->unit.cleanup(); DBUG_RETURN(res); } /* 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 FALSE success TRUE error */ static bool 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; bool res= 0; if (tables && check_table_access(thd, SELECT_ACL, tables, 0)) DBUG_RETURN(TRUE); if (tables && (res= open_and_lock_tables(thd, tables))) goto error; while ((var= it++)) { if (var->light_check(thd)) { stmt->lex->unit.cleanup(); res= TRUE; 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 specific_prepare - function of command specific prepare RETURN VALUE FALSE success TRUE error */ static bool select_like_statement_test(Prepared_statement *stmt, TABLE_LIST *tables, bool (*specific_prepare)(THD *thd), ulong setup_tables_done_option) { DBUG_ENTER("select_like_statement_test"); THD *thd= stmt->thd; LEX *lex= stmt->lex; bool res= 0; /* check that tables was not opened during conversion from usual update */ if (tables && (!tables->table && !tables->view) && (res= open_and_lock_tables(thd, tables))) goto end; if (specific_prepare && (res= (*specific_prepare)(thd))) goto end; thd->used_tables= 0; // Updated by setup_fields // JOIN::prepare calls if (lex->unit.prepare(thd, 0, setup_tables_done_option)) { res= TRUE; } 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) { 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 */ bool link_to_local; TABLE_LIST *create_table= lex->unlink_first_table(&link_to_local); TABLE_LIST *tables= lex->query_tables; 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, 0, 0); select_lex->resolve_mode= SELECT_LEX::NOMATTER_MODE; } /* put tables back for PS rexecuting */ lex->link_first_table_back(create_table, link_to_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 converted converted to multi-update from usual update RETURN VALUE FALSE success TRUE error */ static bool mysql_test_multiupdate(Prepared_statement *stmt, TABLE_LIST *tables, bool converted) { /* if we switched from normal update, rights are checked */ if (!converted && multi_update_precheck(stmt->thd, tables)) return TRUE; /* here we do not pass tables for opening, tables will be opened and locked by mysql_multi_update_prepare */ return select_like_statement_test(stmt, 0, &mysql_multi_update_prepare, OPTION_SETUP_TABLES_DONE); } /* 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; if ((res= select_like_statement_test(stmt, tables, &mysql_multi_delete_prepare, OPTION_SETUP_TABLES_DONE))) return res; if (!tables->table) { DBUG_ASSERT(tables->view && tables->ancestor && tables->ancestor->next_local); my_error(ER_VIEW_DELETE_MERGE_VIEW, MYF(0), tables->view_db.str, tables->view_name.str); return -1; } return 0; } /* 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; TABLE_LIST *first_local_table; if ((res= insert_precheck(stmt->thd, tables))) return res; first_local_table= (TABLE_LIST *)lex->select_lex.table_list.first; DBUG_ASSERT(first_local_table != 0); /* Skip first table, which is the table we are inserting in */ lex->select_lex.table_list.first= (byte*) first_local_table->next_local; if (tables->table) { // don't allocate insert_values tables->table->insert_values=(byte *)1; } /* 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, &mysql_insert_select_prepare, OPTION_SETUP_TABLES_DONE); /* revert changes*/ lex->select_lex.table_list.first= (byte*) first_local_table; lex->select_lex.resolve_mode= SELECT_LEX::INSERT_MODE; return res; } /* Perform semantic analysis of the parsed tree and send a response packet to the client. SYNOPSIS check_prepared_statement() stmt prepared statement DESCRIPTION This function - opens all tables and checks access rights - validates semantics of statement columns and SQL functions by calling fix_fields. RETURN VALUE 0 success 1 error, sent to client */ static int check_prepared_statement(Prepared_statement *stmt, bool text_protocol) { THD *thd= stmt->thd; LEX *lex= stmt->lex; SELECT_LEX *select_lex= &lex->select_lex; TABLE_LIST *tables; enum enum_sql_command sql_command= lex->sql_command; int res= 0; DBUG_ENTER("check_prepared_statement"); DBUG_PRINT("enter",("command: %d, param_count: %ld", sql_command, stmt->param_count)); lex->first_lists_tables_same(); tables= lex->query_tables; /* Preopen 'proc' system table and cache all functions used in this statement. We must do that before we open ordinary tables to avoid deadlocks. We can't open and lock any table once query tables were opened. */ if (lex->sql_command != SQLCOM_CREATE_PROCEDURE && lex->sql_command != SQLCOM_CREATE_SPFUNCTION) { /* the error is print inside */ if (sp_cache_functions(thd, lex)) 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); /* mysql_test_update return 2 if we need to switch to multi-update */ if (res != 2) break; case SQLCOM_UPDATE_MULTI: res= mysql_test_multiupdate(stmt, tables, res == 2); 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); 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_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: case SQLCOM_ALTER_TABLE: case SQLCOM_COMMIT: case SQLCOM_CREATE_INDEX: case SQLCOM_DROP_INDEX: case SQLCOM_ROLLBACK: case SQLCOM_TRUNCATE: break; default: /* All other is not supported yet */ res= -1; my_message(ER_UNSUPPORTED_PS, ER(ER_UNSUPPORTED_PS), MYF(0)); goto error; } if (res == 0) DBUG_RETURN(text_protocol? 0 : (send_prep_stmt(stmt, 0) || thd->protocol->flush())); error: 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 */ my_message(ER_PS_MANY_PARAM, ER(ER_PS_MANY_PARAM), MYF(0)); return TRUE; } 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) return TRUE; for (to= stmt->param_array; to < stmt->param_array + stmt->param_count; ++to) { *to= param_iterator++; } } return FALSE; } /* 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 FALSE OK, statement prepared successfully TRUE 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. */ bool mysql_stmt_prepare(THD *thd, char *packet, uint packet_length, LEX_STRING *name) { LEX *lex; Prepared_statement *stmt= new Prepared_statement(thd); bool error; DBUG_ENTER("mysql_stmt_prepare"); DBUG_PRINT("prep_query", ("%s", packet)); if (stmt == 0) DBUG_RETURN(TRUE); if (name) { stmt->name.length= name->length; if (!(stmt->name.str= memdup_root(stmt->mem_root, (char*)name->str, name->length))) { delete stmt; DBUG_RETURN(TRUE); } } if (thd->stmt_map.insert(stmt)) { delete stmt; DBUG_RETURN(TRUE); } 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); DBUG_RETURN(TRUE); } mysql_log.write(thd, COM_PREPARE, "%s", 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 check_prepared_statement) 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= check_prepared_statement(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); if (error && thd->lex->sphead) { if (lex != thd->lex) thd->lex->sphead->restore_lex(thd); delete thd->lex->sphead; thd->lex->sphead= NULL; } lex_end(lex); thd->restore_backup_statement(stmt, &thd->stmt_backup); cleanup_items(stmt->free_list); close_thread_tables(thd); thd->rollback_item_tree_changes(); thd->cleanup_after_query(); thd->current_arena= thd; if (error) { /* Statement map deletes statement on erase */ thd->stmt_map.erase(stmt); stmt= NULL; } else { stmt->setup_set_params(); 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; stmt->state= Item_arena::PREPARED; } DBUG_RETURN(!stmt); } /* Reinit statement before execution */ void reset_stmt_for_execute(THD *thd, LEX *lex) { SELECT_LEX *sl= lex->all_selects_list; DBUG_ENTER("reset_stmt_for_execute"); if (lex->empty_field_list_on_rset) { lex->empty_field_list_on_rset= 0; lex->field_list.empty(); } for (; sl; sl= sl->next_select_in_list()) { if (!sl->first_execution) { /* 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; } { 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(); } } /* 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= lex->query_tables; tables; tables= tables->next_global) { /* 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; if (tables->nested_join) tables->nested_join->counter= 0; } lex->current_select= &lex->select_lex; /* restore original list used in INSERT ... SELECT */ if (lex->leaf_tables_insert) lex->select_lex.leaf_tables= lex->leaf_tables_insert; if (lex->result) lex->result->cleanup(); DBUG_VOID_RETURN; } /* 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); ulong flags= (ulong) ((uchar) packet[4]); /* 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 */ if (!(stmt= find_prepared_statement(thd, stmt_id, "mysql_stmt_execute"))) 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) { my_message(stmt->last_errno, stmt->last_error, MYF(0)); DBUG_VOID_RETURN; } DBUG_ASSERT(thd->free_list == NULL); mysql_reset_thd_for_next_command(thd); if (flags & (ulong) CURSOR_TYPE_READ_ONLY) { if (!stmt->lex->result || !stmt->lex->result->simple_select()) { DBUG_PRINT("info",("Cursor asked for not SELECT stmt")); /* If lex->result is set in the parser, this is not a SELECT statement: we can't open a cursor for it. */ flags= 0; } else { DBUG_PRINT("info",("Using READ_ONLY cursor")); if (!stmt->cursor && !(stmt->cursor= new (&stmt->main_mem_root) Cursor())) DBUG_VOID_RETURN; /* If lex->result is set, mysql_execute_command will use it */ stmt->lex->result= &stmt->cursor->result; } } #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->stmt_backup.set_statement(thd); thd->set_statement(stmt); thd->current_arena= stmt; reset_stmt_for_execute(thd, stmt->lex); /* From now cursors assume that thd->mem_root is clean */ if (expanded_query.length() && alloc_query(thd, (char *)expanded_query.ptr(), expanded_query.length()+1)) { my_error(ER_OUTOFMEMORY, 0, expanded_query.length()); goto err; } thd->protocol= &thd->protocol_prep; // Switch to binary protocol 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); thd->protocol= &thd->protocol_simple; // Use normal protocol if (flags & (ulong) CURSOR_TYPE_READ_ONLY) { if (stmt->cursor->is_open()) stmt->cursor->init_from_thd(thd); stmt->cursor->state= stmt->state; } else { thd->lex->unit.cleanup(); cleanup_items(stmt->free_list); reset_stmt_params(stmt); close_thread_tables(thd); /* to close derived tables */ thd->rollback_item_tree_changes(); thd->cleanup_after_query(); } thd->set_statement(&thd->stmt_backup); thd->current_arena= thd; DBUG_VOID_RETURN; set_params_data_err: reset_stmt_params(stmt); my_error(ER_WRONG_ARGUMENTS, MYF(0), "mysql_stmt_execute"); err: 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"); DBUG_ASSERT(thd->free_list == NULL); 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"); DBUG_VOID_RETURN; } if (stmt->param_count != thd->lex->prepared_stmt_params.elements) { my_error(ER_WRONG_ARGUMENTS, MYF(0), "EXECUTE"); DBUG_VOID_RETURN; } /* 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); thd->set_statement(stmt); if (stmt->set_params_from_vars(stmt, thd->stmt_backup.lex->prepared_stmt_params, &expanded_query)) { my_error(ER_WRONG_ARGUMENTS, MYF(0), "EXECUTE"); } execute_stmt(thd, stmt, &expanded_query); 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. */ static void execute_stmt(THD *thd, Prepared_statement *stmt, String *expanded_query) { DBUG_ENTER("execute_stmt"); reset_stmt_for_execute(thd, stmt->lex); if (expanded_query->length() && alloc_query(thd, (char *)expanded_query->ptr(), expanded_query->length()+1)) { my_error(ER_OUTOFMEMORY, MYF(0), expanded_query->length()); DBUG_VOID_RETURN; } /* 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); if (!(specialflag & SPECIAL_NO_PRIOR)) my_pthread_setprio(pthread_self(), WAIT_PRIOR); thd->lex->unit.cleanup(); 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); thd->cleanup_after_query(); if (stmt->state == Item_arena::PREPARED) stmt->state= Item_arena::EXECUTED; DBUG_VOID_RETURN; } /* COM_FETCH handler: fetches requested amount of rows from cursor SYNOPSIS mysql_stmt_fetch() thd Thread handler packet Packet from client (with stmt_id & num_rows) packet_length Length of packet */ void mysql_stmt_fetch(THD *thd, char *packet, uint packet_length) { /* assume there is always place for 8-16 bytes */ ulong stmt_id= uint4korr(packet); ulong num_rows= uint4korr(packet+=4); Statement *stmt; int error; DBUG_ENTER("mysql_stmt_fetch"); if (!(stmt= thd->stmt_map.find(stmt_id)) || !stmt->cursor || !stmt->cursor->is_open()) { my_error(ER_UNKNOWN_STMT_HANDLER, MYF(0), stmt_id, "fetch"); DBUG_VOID_RETURN; } thd->current_arena= stmt; thd->set_n_backup_statement(stmt, &thd->stmt_backup); stmt->cursor->init_thd(thd); if (!(specialflag & SPECIAL_NO_PRIOR)) my_pthread_setprio(pthread_self(), QUERY_PRIOR); thd->protocol= &thd->protocol_prep; // Switch to binary protocol error= stmt->cursor->fetch(num_rows); thd->protocol= &thd->protocol_simple; // Use normal protocol if (!(specialflag & SPECIAL_NO_PRIOR)) my_pthread_setprio(pthread_self(), WAIT_PRIOR); /* Restore THD state */ stmt->cursor->reset_thd(thd); thd->restore_backup_statement(stmt, &thd->stmt_backup); thd->current_arena= thd; 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"); if (!(stmt= find_prepared_statement(thd, stmt_id, "mysql_stmt_reset"))) 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"); if (!(stmt= find_prepared_statement(thd, stmt_id, "mysql_stmt_close"))) 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"); #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"))) 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= '\0'; } void Prepared_statement::setup_set_params() { /* Setup binary logging */ if (mysql_bin_log.is_open() && is_update_query(lex->sql_command)) { 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() { if (cursor) cursor->Cursor::~Cursor(); free_items(free_list); delete lex->result; } Item_arena::Type Prepared_statement::type() const { return PREPARED_STATEMENT; }