/* Copyright (C) 2000 MySQL AB & MySQL Finland AB & TCX DataKonsult AB This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; version 2 of the License. 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 */ /* A lexical scanner on a temporary buffer with a yacc interface */ #define MYSQL_LEX 1 #include "mysql_priv.h" #include "item_create.h" #include #include #include "sp.h" #include "sp_head.h" /* We are using pointer to this variable for distinguishing between assignment to NEW row field (when parsing trigger definition) and structured variable. */ sys_var_long_ptr trg_new_row_fake_var(0, 0); /* Macros to look like lex */ #define yyGet() *(lex->ptr++) #define yyGetLast() lex->ptr[-1] #define yyPeek() lex->ptr[0] #define yyPeek2() lex->ptr[1] #define yyUnget() lex->ptr-- #define yySkip() lex->ptr++ #define yyLength() ((uint) (lex->ptr - lex->tok_start)-1) /* Longest standard keyword name */ #define TOCK_NAME_LENGTH 24 /* The following data is based on the latin1 character set, and is only used when comparing keywords */ static uchar to_upper_lex[]= { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90,123,124,125,126,127, 128,129,130,131,132,133,134,135,136,137,138,139,140,141,142,143, 144,145,146,147,148,149,150,151,152,153,154,155,156,157,158,159, 160,161,162,163,164,165,166,167,168,169,170,171,172,173,174,175, 176,177,178,179,180,181,182,183,184,185,186,187,188,189,190,191, 192,193,194,195,196,197,198,199,200,201,202,203,204,205,206,207, 208,209,210,211,212,213,214,215,216,217,218,219,220,221,222,223, 192,193,194,195,196,197,198,199,200,201,202,203,204,205,206,207, 208,209,210,211,212,213,214,247,216,217,218,219,220,221,222,255 }; inline int lex_casecmp(const char *s, const char *t, uint len) { while (len-- != 0 && to_upper_lex[(uchar) *s++] == to_upper_lex[(uchar) *t++]) ; return (int) len+1; } #include "lex_hash.h" void lex_init(void) { uint i; DBUG_ENTER("lex_init"); for (i=0 ; i < array_elements(symbols) ; i++) symbols[i].length=(uchar) strlen(symbols[i].name); for (i=0 ; i < array_elements(sql_functions) ; i++) sql_functions[i].length=(uchar) strlen(sql_functions[i].name); DBUG_VOID_RETURN; } void lex_free(void) { // Call this when daemon ends DBUG_ENTER("lex_free"); DBUG_VOID_RETURN; } /* This is called before every query that is to be parsed. Because of this, it's critical to not do too much things here. (We already do too much here) */ void lex_start(THD *thd, uchar *buf,uint length) { LEX *lex= thd->lex; DBUG_ENTER("lex_start"); lex->thd= lex->unit.thd= thd; lex->buf= lex->ptr= buf; lex->end_of_query= buf+length; lex->context_stack.empty(); lex->unit.init_query(); lex->unit.init_select(); /* 'parent_lex' is used in init_query() so it must be before it. */ lex->select_lex.parent_lex= lex; lex->select_lex.init_query(); lex->value_list.empty(); lex->update_list.empty(); lex->param_list.empty(); lex->view_list.empty(); lex->prepared_stmt_params.empty(); lex->auxiliary_table_list.empty(); lex->unit.next= lex->unit.master= lex->unit.link_next= lex->unit.return_to= 0; lex->unit.prev= lex->unit.link_prev= 0; lex->unit.slave= lex->unit.global_parameters= lex->current_select= lex->all_selects_list= &lex->select_lex; lex->select_lex.master= &lex->unit; lex->select_lex.prev= &lex->unit.slave; lex->select_lex.link_next= lex->select_lex.slave= lex->select_lex.next= 0; lex->select_lex.link_prev= (st_select_lex_node**)&(lex->all_selects_list); lex->select_lex.options= 0; lex->select_lex.sql_cache= SELECT_LEX::SQL_CACHE_UNSPECIFIED; lex->select_lex.init_order(); lex->select_lex.group_list.empty(); lex->describe= 0; lex->subqueries= FALSE; lex->view_prepare_mode= FALSE; lex->stmt_prepare_mode= FALSE; lex->derived_tables= 0; lex->lock_option= TL_READ; lex->found_semicolon= 0; lex->safe_to_cache_query= 1; lex->time_zone_tables_used= 0; lex->leaf_tables_insert= 0; lex->empty_field_list_on_rset= 0; lex->select_lex.select_number= 1; lex->next_state=MY_LEX_START; lex->yylineno = 1; lex->in_comment=0; lex->length=0; lex->select_lex.in_sum_expr=0; lex->select_lex.expr_list.empty(); lex->select_lex.ftfunc_list_alloc.empty(); lex->select_lex.ftfunc_list= &lex->select_lex.ftfunc_list_alloc; lex->select_lex.group_list.empty(); lex->select_lex.order_list.empty(); lex->select_lex.udf_list.empty(); lex->current_select= &lex->select_lex; lex->yacc_yyss=lex->yacc_yyvs=0; lex->ignore_space=test(thd->variables.sql_mode & MODE_IGNORE_SPACE); lex->sql_command= lex->orig_sql_command= SQLCOM_END; lex->duplicates= DUP_ERROR; lex->ignore= 0; lex->sphead= NULL; lex->spcont= NULL; lex->proc_list.first= 0; lex->escape_used= FALSE; lex->reset_query_tables_list(FALSE); lex->nest_level=0 ; lex->allow_sum_func= 0; lex->in_sum_func= NULL; DBUG_VOID_RETURN; } void lex_end(LEX *lex) { DBUG_ENTER("lex_end"); DBUG_PRINT("enter", ("lex: 0x%lx", (long) lex)); x_free(lex->yacc_yyss); x_free(lex->yacc_yyvs); DBUG_VOID_RETURN; } static int find_keyword(LEX *lex, uint len, bool function) { uchar *tok=lex->tok_start; SYMBOL *symbol = get_hash_symbol((const char *)tok,len,function); if (symbol) { lex->yylval->symbol.symbol=symbol; lex->yylval->symbol.str= (char*) tok; lex->yylval->symbol.length=len; if ((symbol->tok == NOT_SYM) && (lex->thd->variables.sql_mode & MODE_HIGH_NOT_PRECEDENCE)) return NOT2_SYM; if ((symbol->tok == OR_OR_SYM) && !(lex->thd->variables.sql_mode & MODE_PIPES_AS_CONCAT)) return OR2_SYM; return symbol->tok; } return 0; } /* Check if name is a keyword SYNOPSIS is_keyword() name checked name (must not be empty) len length of checked name RETURN VALUES 0 name is a keyword 1 name isn't a keyword */ bool is_keyword(const char *name, uint len) { DBUG_ASSERT(len != 0); return get_hash_symbol(name,len,0)!=0; } /* make a copy of token before ptr and set yytoklen */ static LEX_STRING get_token(LEX *lex,uint length) { LEX_STRING tmp; yyUnget(); // ptr points now after last token char tmp.length=lex->yytoklen=length; tmp.str=(char*) lex->thd->strmake((char*) lex->tok_start,tmp.length); return tmp; } /* todo: There are no dangerous charsets in mysql for function get_quoted_token yet. But it should be fixed in the future to operate multichar strings (like ucs2) */ static LEX_STRING get_quoted_token(LEX *lex,uint length, char quote) { LEX_STRING tmp; byte *from, *to, *end; yyUnget(); // ptr points now after last token char tmp.length=lex->yytoklen=length; tmp.str=(char*) lex->thd->alloc(tmp.length+1); for (from= (byte*) lex->tok_start, to= (byte*) tmp.str, end= to+length ; to != end ; ) { if ((*to++= *from++) == quote) from++; // Skip double quotes } *to= 0; // End null for safety return tmp; } /* Return an unescaped text literal without quotes Fix sometimes to do only one scan of the string */ static char *get_text(LEX *lex) { reg1 uchar c,sep; uint found_escape=0; CHARSET_INFO *cs= lex->thd->charset(); sep= yyGetLast(); // String should end with this //lex->tok_start=lex->ptr-1; // Remember ' while (lex->ptr != lex->end_of_query) { c = yyGet(); #ifdef USE_MB int l; if (use_mb(cs) && (l = my_ismbchar(cs, (const char *)lex->ptr-1, (const char *)lex->end_of_query))) { lex->ptr += l-1; continue; } #endif if (c == '\\' && !(lex->thd->variables.sql_mode & MODE_NO_BACKSLASH_ESCAPES)) { // Escaped character found_escape=1; if (lex->ptr == lex->end_of_query) return 0; yySkip(); } else if (c == sep) { if (c == yyGet()) // Check if two separators in a row { found_escape=1; // dupplicate. Remember for delete continue; } else yyUnget(); /* Found end. Unescape and return string */ uchar *str,*end,*start; str=lex->tok_start+1; end=lex->ptr-1; if (!(start=(uchar*) lex->thd->alloc((uint) (end-str)+1))) return (char*) ""; // Sql_alloc has set error flag if (!found_escape) { lex->yytoklen=(uint) (end-str); memcpy(start,str,lex->yytoklen); start[lex->yytoklen]=0; } else { uchar *to; for (to=start ; str != end ; str++) { #ifdef USE_MB int l; if (use_mb(cs) && (l = my_ismbchar(cs, (const char *)str, (const char *)end))) { while (l--) *to++ = *str++; str--; continue; } #endif if (!(lex->thd->variables.sql_mode & MODE_NO_BACKSLASH_ESCAPES) && *str == '\\' && str+1 != end) { switch(*++str) { case 'n': *to++='\n'; break; case 't': *to++= '\t'; break; case 'r': *to++ = '\r'; break; case 'b': *to++ = '\b'; break; case '0': *to++= 0; // Ascii null break; case 'Z': // ^Z must be escaped on Win32 *to++='\032'; break; case '_': case '%': *to++= '\\'; // remember prefix for wildcard /* Fall through */ default: *to++= *str; break; } } else if (*str == sep) *to++= *str++; // Two ' or " else *to++ = *str; } *to=0; lex->yytoklen=(uint) (to-start); } return (char*) start; } } return 0; // unexpected end of query } /* ** Calc type of integer; long integer, longlong integer or real. ** Returns smallest type that match the string. ** When using unsigned long long values the result is converted to a real ** because else they will be unexpected sign changes because all calculation ** is done with longlong or double. */ static const char *long_str="2147483647"; static const uint long_len=10; static const char *signed_long_str="-2147483648"; static const char *longlong_str="9223372036854775807"; static const uint longlong_len=19; static const char *signed_longlong_str="-9223372036854775808"; static const uint signed_longlong_len=19; static const char *unsigned_longlong_str="18446744073709551615"; static const uint unsigned_longlong_len=20; static inline uint int_token(const char *str,uint length) { if (length < long_len) // quick normal case return NUM; bool neg=0; if (*str == '+') // Remove sign and pre-zeros { str++; length--; } else if (*str == '-') { str++; length--; neg=1; } while (*str == '0' && length) { str++; length --; } if (length < long_len) return NUM; uint smaller,bigger; const char *cmp; if (neg) { if (length == long_len) { cmp= signed_long_str+1; smaller=NUM; // If <= signed_long_str bigger=LONG_NUM; // If >= signed_long_str } else if (length < signed_longlong_len) return LONG_NUM; else if (length > signed_longlong_len) return DECIMAL_NUM; else { cmp=signed_longlong_str+1; smaller=LONG_NUM; // If <= signed_longlong_str bigger=DECIMAL_NUM; } } else { if (length == long_len) { cmp= long_str; smaller=NUM; bigger=LONG_NUM; } else if (length < longlong_len) return LONG_NUM; else if (length > longlong_len) { if (length > unsigned_longlong_len) return DECIMAL_NUM; cmp=unsigned_longlong_str; smaller=ULONGLONG_NUM; bigger=DECIMAL_NUM; } else { cmp=longlong_str; smaller=LONG_NUM; bigger= ULONGLONG_NUM; } } while (*cmp && *cmp++ == *str++) ; return ((uchar) str[-1] <= (uchar) cmp[-1]) ? smaller : bigger; } /* MYSQLlex remember the following states from the following MYSQLlex() - MY_LEX_EOQ Found end of query - MY_LEX_OPERATOR_OR_IDENT Last state was an ident, text or number (which can't be followed by a signed number) */ int MYSQLlex(void *arg, void *yythd) { reg1 uchar c; int tokval, result_state; uint length; enum my_lex_states state; LEX *lex= ((THD *)yythd)->lex; YYSTYPE *yylval=(YYSTYPE*) arg; CHARSET_INFO *cs= ((THD *) yythd)->charset(); uchar *state_map= cs->state_map; uchar *ident_map= cs->ident_map; lex->yylval=yylval; // The global state lex->tok_end_prev= lex->tok_end; lex->tok_start_prev= lex->tok_start; lex->tok_start=lex->tok_end=lex->ptr; state=lex->next_state; lex->next_state=MY_LEX_OPERATOR_OR_IDENT; LINT_INIT(c); for (;;) { switch (state) { case MY_LEX_OPERATOR_OR_IDENT: // Next is operator or keyword case MY_LEX_START: // Start of token // Skip startspace for (c=yyGet() ; (state_map[c] == MY_LEX_SKIP) ; c= yyGet()) { if (c == '\n') lex->yylineno++; } lex->tok_start=lex->ptr-1; // Start of real token state= (enum my_lex_states) state_map[c]; break; case MY_LEX_ESCAPE: if (yyGet() == 'N') { // Allow \N as shortcut for NULL yylval->lex_str.str=(char*) "\\N"; yylval->lex_str.length=2; return NULL_SYM; } case MY_LEX_CHAR: // Unknown or single char token case MY_LEX_SKIP: // This should not happen if (c == '-' && yyPeek() == '-' && (my_isspace(cs,yyPeek2()) || my_iscntrl(cs,yyPeek2()))) { state=MY_LEX_COMMENT; break; } yylval->lex_str.str=(char*) (lex->ptr=lex->tok_start);// Set to first chr yylval->lex_str.length=1; c=yyGet(); if (c != ')') lex->next_state= MY_LEX_START; // Allow signed numbers if (c == ',') lex->tok_start=lex->ptr; // Let tok_start point at next item /* Check for a placeholder: it should not precede a possible identifier because of binlogging: when a placeholder is replaced with its value in a query for the binlog, the query must stay grammatically correct. */ else if (c == '?' && lex->stmt_prepare_mode && !ident_map[yyPeek()]) return(PARAM_MARKER); return((int) c); case MY_LEX_IDENT_OR_NCHAR: if (yyPeek() != '\'') { state= MY_LEX_IDENT; break; } /* Found N'string' */ lex->tok_start++; // Skip N yySkip(); // Skip ' if (!(yylval->lex_str.str = get_text(lex))) { state= MY_LEX_CHAR; // Read char by char break; } yylval->lex_str.length= lex->yytoklen; return(NCHAR_STRING); case MY_LEX_IDENT_OR_HEX: if (yyPeek() == '\'') { // Found x'hex-number' state= MY_LEX_HEX_NUMBER; break; } case MY_LEX_IDENT_OR_BIN: if (yyPeek() == '\'') { // Found b'bin-number' state= MY_LEX_BIN_NUMBER; break; } case MY_LEX_IDENT: uchar *start; #if defined(USE_MB) && defined(USE_MB_IDENT) if (use_mb(cs)) { result_state= IDENT_QUOTED; if (my_mbcharlen(cs, yyGetLast()) > 1) { int l = my_ismbchar(cs, (const char *)lex->ptr-1, (const char *)lex->end_of_query); if (l == 0) { state = MY_LEX_CHAR; continue; } lex->ptr += l - 1; } while (ident_map[c=yyGet()]) { if (my_mbcharlen(cs, c) > 1) { int l; if ((l = my_ismbchar(cs, (const char *)lex->ptr-1, (const char *)lex->end_of_query)) == 0) break; lex->ptr += l-1; } } } else #endif { for (result_state= c; ident_map[c= yyGet()]; result_state|= c); /* If there were non-ASCII characters, mark that we must convert */ result_state= result_state & 0x80 ? IDENT_QUOTED : IDENT; } length= (uint) (lex->ptr - lex->tok_start)-1; start= lex->ptr; if (lex->ignore_space) { /* If we find a space then this can't be an identifier. We notice this below by checking start != lex->ptr. */ for (; state_map[c] == MY_LEX_SKIP ; c= yyGet()); } if (start == lex->ptr && c == '.' && ident_map[yyPeek()]) lex->next_state=MY_LEX_IDENT_SEP; else { // '(' must follow directly if function yyUnget(); if ((tokval = find_keyword(lex,length,c == '('))) { lex->next_state= MY_LEX_START; // Allow signed numbers return(tokval); // Was keyword } yySkip(); // next state does a unget } yylval->lex_str=get_token(lex,length); /* Note: "SELECT _bla AS 'alias'" _bla should be considered as a IDENT if charset haven't been found. So we don't use MYF(MY_WME) with get_charset_by_csname to avoid producing an error. */ if ((yylval->lex_str.str[0]=='_') && (lex->underscore_charset= get_charset_by_csname(yylval->lex_str.str + 1, MY_CS_PRIMARY,MYF(0)))) return(UNDERSCORE_CHARSET); return(result_state); // IDENT or IDENT_QUOTED case MY_LEX_IDENT_SEP: // Found ident and now '.' yylval->lex_str.str=(char*) lex->ptr; yylval->lex_str.length=1; c=yyGet(); // should be '.' lex->next_state= MY_LEX_IDENT_START;// Next is an ident (not a keyword) if (!ident_map[yyPeek()]) // Probably ` or " lex->next_state= MY_LEX_START; return((int) c); case MY_LEX_NUMBER_IDENT: // number or ident which num-start while (my_isdigit(cs,(c = yyGet()))) ; if (!ident_map[c]) { // Can't be identifier state=MY_LEX_INT_OR_REAL; break; } if (c == 'e' || c == 'E') { // The following test is written this way to allow numbers of type 1e1 if (my_isdigit(cs,yyPeek()) || (c=(yyGet())) == '+' || c == '-') { // Allow 1E+10 if (my_isdigit(cs,yyPeek())) // Number must have digit after sign { yySkip(); while (my_isdigit(cs,yyGet())) ; yylval->lex_str=get_token(lex,yyLength()); return(FLOAT_NUM); } } yyUnget(); /* purecov: inspected */ } else if (c == 'x' && (lex->ptr - lex->tok_start) == 2 && lex->tok_start[0] == '0' ) { // Varbinary while (my_isxdigit(cs,(c = yyGet()))) ; if ((lex->ptr - lex->tok_start) >= 4 && !ident_map[c]) { yylval->lex_str=get_token(lex,yyLength()); yylval->lex_str.str+=2; // Skip 0x yylval->lex_str.length-=2; lex->yytoklen-=2; return (HEX_NUM); } yyUnget(); } else if (c == 'b' && (lex->ptr - lex->tok_start) == 2 && lex->tok_start[0] == '0' ) { // b'bin-number' while (my_isxdigit(cs,(c = yyGet()))) ; if ((lex->ptr - lex->tok_start) >= 4 && !ident_map[c]) { yylval->lex_str= get_token(lex, yyLength()); yylval->lex_str.str+= 2; // Skip 0x yylval->lex_str.length-= 2; lex->yytoklen-= 2; return (BIN_NUM); } yyUnget(); } // fall through case MY_LEX_IDENT_START: // We come here after '.' result_state= IDENT; #if defined(USE_MB) && defined(USE_MB_IDENT) if (use_mb(cs)) { result_state= IDENT_QUOTED; while (ident_map[c=yyGet()]) { if (my_mbcharlen(cs, c) > 1) { int l; if ((l = my_ismbchar(cs, (const char *)lex->ptr-1, (const char *)lex->end_of_query)) == 0) break; lex->ptr += l-1; } } } else #endif { for (result_state=0; ident_map[c= yyGet()]; result_state|= c); /* If there were non-ASCII characters, mark that we must convert */ result_state= result_state & 0x80 ? IDENT_QUOTED : IDENT; } if (c == '.' && ident_map[yyPeek()]) lex->next_state=MY_LEX_IDENT_SEP;// Next is '.' yylval->lex_str= get_token(lex,yyLength()); return(result_state); case MY_LEX_USER_VARIABLE_DELIMITER: // Found quote char { uint double_quotes= 0; char quote_char= c; // Used char lex->tok_start=lex->ptr; // Skip first ` while ((c=yyGet())) { int length; if ((length= my_mbcharlen(cs, c)) == 1) { if (c == (uchar) NAMES_SEP_CHAR) break; /* Old .frm format can't handle this char */ if (c == quote_char) { if (yyPeek() != quote_char) break; c=yyGet(); double_quotes++; continue; } } #ifdef USE_MB else if (length < 1) break; // Error lex->ptr+= length-1; #endif } if (double_quotes) yylval->lex_str=get_quoted_token(lex,yyLength() - double_quotes, quote_char); else yylval->lex_str=get_token(lex,yyLength()); if (c == quote_char) yySkip(); // Skip end ` lex->next_state= MY_LEX_START; return(IDENT_QUOTED); } case MY_LEX_INT_OR_REAL: // Compleat int or incompleat real if (c != '.') { // Found complete integer number. yylval->lex_str=get_token(lex,yyLength()); return int_token(yylval->lex_str.str,yylval->lex_str.length); } // fall through case MY_LEX_REAL: // Incomplete real number while (my_isdigit(cs,c = yyGet())) ; if (c == 'e' || c == 'E') { c = yyGet(); if (c == '-' || c == '+') c = yyGet(); // Skip sign if (!my_isdigit(cs,c)) { // No digit after sign state= MY_LEX_CHAR; break; } while (my_isdigit(cs,yyGet())) ; yylval->lex_str=get_token(lex,yyLength()); return(FLOAT_NUM); } yylval->lex_str=get_token(lex,yyLength()); return(DECIMAL_NUM); case MY_LEX_HEX_NUMBER: // Found x'hexstring' yyGet(); // Skip ' while (my_isxdigit(cs,(c = yyGet()))) ; length=(lex->ptr - lex->tok_start); // Length of hexnum+3 if (!(length & 1) || c != '\'') { return(ABORT_SYM); // Illegal hex constant } yyGet(); // get_token makes an unget yylval->lex_str=get_token(lex,length); yylval->lex_str.str+=2; // Skip x' yylval->lex_str.length-=3; // Don't count x' and last ' lex->yytoklen-=3; return (HEX_NUM); case MY_LEX_BIN_NUMBER: // Found b'bin-string' yyGet(); // Skip ' while ((c= yyGet()) == '0' || c == '1'); length= (lex->ptr - lex->tok_start); // Length of bin-num + 3 if (c != '\'') return(ABORT_SYM); // Illegal hex constant yyGet(); // get_token makes an unget yylval->lex_str= get_token(lex, length); yylval->lex_str.str+= 2; // Skip b' yylval->lex_str.length-= 3; // Don't count b' and last ' lex->yytoklen-= 3; return (BIN_NUM); case MY_LEX_CMP_OP: // Incomplete comparison operator if (state_map[yyPeek()] == MY_LEX_CMP_OP || state_map[yyPeek()] == MY_LEX_LONG_CMP_OP) yySkip(); if ((tokval = find_keyword(lex,(uint) (lex->ptr - lex->tok_start),0))) { lex->next_state= MY_LEX_START; // Allow signed numbers return(tokval); } state = MY_LEX_CHAR; // Something fishy found break; case MY_LEX_LONG_CMP_OP: // Incomplete comparison operator if (state_map[yyPeek()] == MY_LEX_CMP_OP || state_map[yyPeek()] == MY_LEX_LONG_CMP_OP) { yySkip(); if (state_map[yyPeek()] == MY_LEX_CMP_OP) yySkip(); } if ((tokval = find_keyword(lex,(uint) (lex->ptr - lex->tok_start),0))) { lex->next_state= MY_LEX_START; // Found long op return(tokval); } state = MY_LEX_CHAR; // Something fishy found break; case MY_LEX_BOOL: if (c != yyPeek()) { state=MY_LEX_CHAR; break; } yySkip(); tokval = find_keyword(lex,2,0); // Is a bool operator lex->next_state= MY_LEX_START; // Allow signed numbers return(tokval); case MY_LEX_STRING_OR_DELIMITER: if (((THD *) yythd)->variables.sql_mode & MODE_ANSI_QUOTES) { state= MY_LEX_USER_VARIABLE_DELIMITER; break; } /* " used for strings */ case MY_LEX_STRING: // Incomplete text string if (!(yylval->lex_str.str = get_text(lex))) { state= MY_LEX_CHAR; // Read char by char break; } yylval->lex_str.length=lex->yytoklen; return(TEXT_STRING); case MY_LEX_COMMENT: // Comment lex->select_lex.options|= OPTION_FOUND_COMMENT; while ((c = yyGet()) != '\n' && c) ; yyUnget(); // Safety against eof state = MY_LEX_START; // Try again break; case MY_LEX_LONG_COMMENT: /* Long C comment? */ if (yyPeek() != '*') { state=MY_LEX_CHAR; // Probable division break; } yySkip(); // Skip '*' lex->select_lex.options|= OPTION_FOUND_COMMENT; if (yyPeek() == '!') // MySQL command in comment { ulong version=MYSQL_VERSION_ID; yySkip(); state=MY_LEX_START; if (my_isdigit(cs,yyPeek())) { // Version number version=strtol((char*) lex->ptr,(char**) &lex->ptr,10); } if (version <= MYSQL_VERSION_ID) { lex->in_comment=1; break; } } while (lex->ptr != lex->end_of_query && ((c=yyGet()) != '*' || yyPeek() != '/')) { if (c == '\n') lex->yylineno++; } if (lex->ptr != lex->end_of_query) yySkip(); // remove last '/' state = MY_LEX_START; // Try again break; case MY_LEX_END_LONG_COMMENT: if (lex->in_comment && yyPeek() == '/') { yySkip(); lex->in_comment=0; state=MY_LEX_START; } else state=MY_LEX_CHAR; // Return '*' break; case MY_LEX_SET_VAR: // Check if ':=' if (yyPeek() != '=') { state=MY_LEX_CHAR; // Return ':' break; } yySkip(); return (SET_VAR); case MY_LEX_SEMICOLON: // optional line terminator if (yyPeek()) { THD* thd= (THD*)yythd; if ((thd->client_capabilities & CLIENT_MULTI_STATEMENTS) && !lex->stmt_prepare_mode) { lex->safe_to_cache_query= 0; lex->found_semicolon=(char*) lex->ptr; thd->server_status|= SERVER_MORE_RESULTS_EXISTS; lex->next_state= MY_LEX_END; return (END_OF_INPUT); } state= MY_LEX_CHAR; // Return ';' break; } /* fall true */ case MY_LEX_EOL: if (lex->ptr >= lex->end_of_query) { lex->next_state=MY_LEX_END; // Mark for next loop return(END_OF_INPUT); } state=MY_LEX_CHAR; break; case MY_LEX_END: lex->next_state=MY_LEX_END; return(0); // We found end of input last time /* Actually real shouldn't start with . but allow them anyhow */ case MY_LEX_REAL_OR_POINT: if (my_isdigit(cs,yyPeek())) state = MY_LEX_REAL; // Real else { state= MY_LEX_IDENT_SEP; // return '.' yyUnget(); // Put back '.' } break; case MY_LEX_USER_END: // end '@' of user@hostname switch (state_map[yyPeek()]) { case MY_LEX_STRING: case MY_LEX_USER_VARIABLE_DELIMITER: case MY_LEX_STRING_OR_DELIMITER: break; case MY_LEX_USER_END: lex->next_state=MY_LEX_SYSTEM_VAR; break; default: lex->next_state=MY_LEX_HOSTNAME; break; } yylval->lex_str.str=(char*) lex->ptr; yylval->lex_str.length=1; return((int) '@'); case MY_LEX_HOSTNAME: // end '@' of user@hostname for (c=yyGet() ; my_isalnum(cs,c) || c == '.' || c == '_' || c == '$'; c= yyGet()) ; yylval->lex_str=get_token(lex,yyLength()); return(LEX_HOSTNAME); case MY_LEX_SYSTEM_VAR: yylval->lex_str.str=(char*) lex->ptr; yylval->lex_str.length=1; yySkip(); // Skip '@' lex->next_state= (state_map[yyPeek()] == MY_LEX_USER_VARIABLE_DELIMITER ? MY_LEX_OPERATOR_OR_IDENT : MY_LEX_IDENT_OR_KEYWORD); return((int) '@'); case MY_LEX_IDENT_OR_KEYWORD: /* We come here when we have found two '@' in a row. We should now be able to handle: [(global | local | session) .]variable_name */ for (result_state= 0; ident_map[c= yyGet()]; result_state|= c); /* If there were non-ASCII characters, mark that we must convert */ result_state= result_state & 0x80 ? IDENT_QUOTED : IDENT; if (c == '.') lex->next_state=MY_LEX_IDENT_SEP; length= (uint) (lex->ptr - lex->tok_start)-1; if (length == 0) return(ABORT_SYM); // Names must be nonempty. if ((tokval= find_keyword(lex,length,0))) { yyUnget(); // Put back 'c' return(tokval); // Was keyword } yylval->lex_str=get_token(lex,length); return(result_state); } } } /* Skip comment in the end of statement. SYNOPSIS skip_rear_comments() begin pointer to the beginning of statement end pointer to the end of statement DESCRIPTION The function is intended to trim comments at the end of the statement. RETURN Pointer to the last non-comment symbol of the statement. */ uchar *skip_rear_comments(uchar *begin, uchar *end) { while (begin < end && (end[-1] <= ' ' || end[-1] == '*' || end[-1] == '/' || end[-1] == ';')) end-= 1; return end; } /* st_select_lex structures initialisations */ void st_select_lex_node::init_query() { options= 0; sql_cache= SQL_CACHE_UNSPECIFIED; linkage= UNSPECIFIED_TYPE; no_error= no_table_names_allowed= 0; uncacheable= 0; } void st_select_lex_node::init_select() { } void st_select_lex_unit::init_query() { st_select_lex_node::init_query(); linkage= GLOBAL_OPTIONS_TYPE; global_parameters= first_select(); select_limit_cnt= HA_POS_ERROR; offset_limit_cnt= 0; union_distinct= 0; prepared= optimized= executed= 0; item= 0; union_result= 0; table= 0; fake_select_lex= 0; cleaned= 0; item_list.empty(); describe= 0; found_rows_for_union= 0; } void st_select_lex::init_query() { st_select_lex_node::init_query(); table_list.empty(); top_join_list.empty(); join_list= &top_join_list; embedding= leaf_tables= 0; item_list.empty(); join= 0; having= prep_having= where= prep_where= 0; olap= UNSPECIFIED_OLAP_TYPE; having_fix_field= 0; context.select_lex= this; context.init(); /* Add the name resolution context of the current (sub)query to the stack of contexts for the whole query. TODO: push_context may return an error if there is no memory for a new element in the stack, however this method has no return value, thus push_context should be moved to a place where query initialization is checked for failure. */ parent_lex->push_context(&context); cond_count= between_count= with_wild= 0; conds_processed_with_permanent_arena= 0; ref_pointer_array= 0; select_n_having_items= 0; subquery_in_having= explicit_limit= 0; is_item_list_lookup= 0; first_execution= 1; first_cond_optimization= 1; parsing_place= NO_MATTER; exclude_from_table_unique_test= no_wrap_view_item= FALSE; nest_level= 0; link_next= 0; } void st_select_lex::init_select() { st_select_lex_node::init_select(); group_list.empty(); type= db= 0; having= 0; use_index_ptr= ignore_index_ptr= 0; table_join_options= 0; in_sum_expr= with_wild= 0; options= 0; sql_cache= SQL_CACHE_UNSPECIFIED; braces= 0; when_list.empty(); expr_list.empty(); udf_list.empty(); interval_list.empty(); use_index.empty(); ftfunc_list_alloc.empty(); inner_sum_func_list= 0; ftfunc_list= &ftfunc_list_alloc; linkage= UNSPECIFIED_TYPE; order_list.elements= 0; order_list.first= 0; order_list.next= (byte**) &order_list.first; /* Set limit and offset to default values */ select_limit= 0; /* denotes the default limit = HA_POS_ERROR */ offset_limit= 0; /* denotes the default offset = 0 */ with_sum_func= 0; is_correlated= 0; } /* st_select_lex structures linking */ /* include on level down */ void st_select_lex_node::include_down(st_select_lex_node *upper) { if ((next= upper->slave)) next->prev= &next; prev= &upper->slave; upper->slave= this; master= upper; slave= 0; } /* include on level down (but do not link) SYNOPSYS st_select_lex_node::include_standalone() upper - reference on node underr which this node should be included ref - references on reference on this node */ void st_select_lex_node::include_standalone(st_select_lex_node *upper, st_select_lex_node **ref) { next= 0; prev= ref; master= upper; slave= 0; } /* include neighbour (on same level) */ void st_select_lex_node::include_neighbour(st_select_lex_node *before) { if ((next= before->next)) next->prev= &next; prev= &before->next; before->next= this; master= before->master; slave= 0; } /* including in global SELECT_LEX list */ void st_select_lex_node::include_global(st_select_lex_node **plink) { if ((link_next= *plink)) link_next->link_prev= &link_next; link_prev= plink; *plink= this; } //excluding from global list (internal function) void st_select_lex_node::fast_exclude() { if (link_prev) { if ((*link_prev= link_next)) link_next->link_prev= link_prev; } // Remove slave structure for (; slave; slave= slave->next) slave->fast_exclude(); } /* excluding select_lex structure (except first (first select can't be deleted, because it is most upper select)) */ void st_select_lex_node::exclude() { //exclude from global list fast_exclude(); //exclude from other structures if ((*prev= next)) next->prev= prev; /* We do not need following statements, because prev pointer of first list element point to master->slave if (master->slave == this) master->slave= next; */ } /* Exclude level of current unit from tree of SELECTs SYNOPSYS st_select_lex_unit::exclude_level() NOTE: units which belong to current will be brought up on level of currernt unit */ void st_select_lex_unit::exclude_level() { SELECT_LEX_UNIT *units= 0, **units_last= &units; for (SELECT_LEX *sl= first_select(); sl; sl= sl->next_select()) { // unlink current level from global SELECTs list if (sl->link_prev && (*sl->link_prev= sl->link_next)) sl->link_next->link_prev= sl->link_prev; // bring up underlay levels SELECT_LEX_UNIT **last= 0; for (SELECT_LEX_UNIT *u= sl->first_inner_unit(); u; u= u->next_unit()) { u->master= master; last= (SELECT_LEX_UNIT**)&(u->next); } if (last) { (*units_last)= sl->first_inner_unit(); units_last= last; } } if (units) { // include brought up levels in place of current (*prev)= units; (*units_last)= (SELECT_LEX_UNIT*)next; if (next) next->prev= (SELECT_LEX_NODE**)units_last; units->prev= prev; } else { // exclude currect unit from list of nodes (*prev)= next; if (next) next->prev= prev; } } /* Exclude subtree of current unit from tree of SELECTs SYNOPSYS st_select_lex_unit::exclude_tree() */ void st_select_lex_unit::exclude_tree() { for (SELECT_LEX *sl= first_select(); sl; sl= sl->next_select()) { // unlink current level from global SELECTs list if (sl->link_prev && (*sl->link_prev= sl->link_next)) sl->link_next->link_prev= sl->link_prev; // unlink underlay levels for (SELECT_LEX_UNIT *u= sl->first_inner_unit(); u; u= u->next_unit()) { u->exclude_level(); } } // exclude currect unit from list of nodes (*prev)= next; if (next) next->prev= prev; } /* st_select_lex_node::mark_as_dependent mark all st_select_lex struct from this to 'last' as dependent SYNOPSIS last - pointer to last st_select_lex struct, before wich all st_select_lex have to be marked as dependent NOTE 'last' should be reachable from this st_select_lex_node */ void st_select_lex::mark_as_dependent(SELECT_LEX *last) { /* Mark all selects from resolved to 1 before select where was found table as depended (of select where was found table) */ for (SELECT_LEX *s= this; s && s != last; s= s->outer_select()) if (!(s->uncacheable & UNCACHEABLE_DEPENDENT)) { // Select is dependent of outer select s->uncacheable|= UNCACHEABLE_DEPENDENT; SELECT_LEX_UNIT *munit= s->master_unit(); munit->uncacheable|= UNCACHEABLE_DEPENDENT; } is_correlated= TRUE; this->master_unit()->item->is_correlated= TRUE; } bool st_select_lex_node::set_braces(bool value) { return 1; } bool st_select_lex_node::inc_in_sum_expr() { return 1; } uint st_select_lex_node::get_in_sum_expr() { return 0; } TABLE_LIST* st_select_lex_node::get_table_list() { return 0; } List* st_select_lex_node::get_item_list() { return 0; } List* st_select_lex_node::get_use_index() { return 0; } List* st_select_lex_node::get_ignore_index() { return 0; } TABLE_LIST *st_select_lex_node::add_table_to_list(THD *thd, Table_ident *table, LEX_STRING *alias, ulong table_join_options, thr_lock_type flags, List *use_index, List *ignore_index, LEX_STRING *option) { return 0; } ulong st_select_lex_node::get_table_join_options() { return 0; } /* prohibit using LIMIT clause */ bool st_select_lex::test_limit() { if (select_limit != 0) { my_error(ER_NOT_SUPPORTED_YET, MYF(0), "LIMIT & IN/ALL/ANY/SOME subquery"); return(1); } // no sense in ORDER BY without LIMIT order_list.empty(); return(0); } st_select_lex_unit* st_select_lex_unit::master_unit() { return this; } st_select_lex* st_select_lex_unit::outer_select() { return (st_select_lex*) master; } bool st_select_lex::add_order_to_list(THD *thd, Item *item, bool asc) { return add_to_list(thd, order_list, item, asc); } bool st_select_lex::add_item_to_list(THD *thd, Item *item) { DBUG_ENTER("st_select_lex::add_item_to_list"); DBUG_PRINT("info", ("Item: %p", item)); DBUG_RETURN(item_list.push_back(item)); } bool st_select_lex::add_group_to_list(THD *thd, Item *item, bool asc) { return add_to_list(thd, group_list, item, asc); } bool st_select_lex::add_ftfunc_to_list(Item_func_match *func) { return !func || ftfunc_list->push_back(func); // end of memory? } st_select_lex_unit* st_select_lex::master_unit() { return (st_select_lex_unit*) master; } st_select_lex* st_select_lex::outer_select() { return (st_select_lex*) master->get_master(); } bool st_select_lex::set_braces(bool value) { braces= value; return 0; } bool st_select_lex::inc_in_sum_expr() { in_sum_expr++; return 0; } uint st_select_lex::get_in_sum_expr() { return in_sum_expr; } TABLE_LIST* st_select_lex::get_table_list() { return (TABLE_LIST*) table_list.first; } List* st_select_lex::get_item_list() { return &item_list; } List* st_select_lex::get_use_index() { return use_index_ptr; } List* st_select_lex::get_ignore_index() { return ignore_index_ptr; } ulong st_select_lex::get_table_join_options() { return table_join_options; } bool st_select_lex::setup_ref_array(THD *thd, uint order_group_num) { if (ref_pointer_array) return 0; /* We have to create array in prepared statement memory if it is prepared statement */ Query_arena *arena= thd->stmt_arena; return (ref_pointer_array= (Item **)arena->alloc(sizeof(Item*) * (n_child_sum_items + item_list.elements + select_n_having_items + order_group_num)*5)) == 0; } void st_select_lex_unit::print(String *str) { bool union_all= !union_distinct; for (SELECT_LEX *sl= first_select(); sl; sl= sl->next_select()) { if (sl != first_select()) { str->append(STRING_WITH_LEN(" union ")); if (union_all) str->append(STRING_WITH_LEN("all ")); else if (union_distinct == sl) union_all= TRUE; } if (sl->braces) str->append('('); sl->print(thd, str); if (sl->braces) str->append(')'); } if (fake_select_lex == global_parameters) { if (fake_select_lex->order_list.elements) { str->append(STRING_WITH_LEN(" order by ")); fake_select_lex->print_order(str, (ORDER *) fake_select_lex-> order_list.first); } fake_select_lex->print_limit(thd, str); } } void st_select_lex::print_order(String *str, ORDER *order) { for (; order; order= order->next) { if (order->counter_used) { char buffer[20]; uint length= my_snprintf(buffer, 20, "%d", order->counter); str->append(buffer, length); } else (*order->item)->print(str); if (!order->asc) str->append(STRING_WITH_LEN(" desc")); if (order->next) str->append(','); } } void st_select_lex::print_limit(THD *thd, String *str) { SELECT_LEX_UNIT *unit= master_unit(); Item_subselect *item= unit->item; if (item && unit->global_parameters == this && (item->substype() == Item_subselect::EXISTS_SUBS || item->substype() == Item_subselect::IN_SUBS || item->substype() == Item_subselect::ALL_SUBS)) { DBUG_ASSERT(!item->fixed || select_limit->val_int() == LL(1) && offset_limit == 0); return; } if (explicit_limit) { str->append(STRING_WITH_LEN(" limit ")); if (offset_limit) { offset_limit->print(str); str->append(','); } select_limit->print(str); } } /* Initialize (or reset) Query_tables_list object. SYNOPSIS reset_query_tables_list() init TRUE - we should perform full initialization of object with allocating needed memory FALSE - object is already initialized so we should only reset its state so it can be used for parsing/processing of new statement DESCRIPTION This method initializes Query_tables_list so it can be used as part of LEX object for parsing/processing of statement. One can also use this method to reset state of already initialized Query_tables_list so it can be used for processing of new statement. */ void Query_tables_list::reset_query_tables_list(bool init) { query_tables= 0; query_tables_last= &query_tables; query_tables_own_last= 0; if (init) { /* We delay real initialization of hash (and therefore related memory allocation) until first insertion into this hash. */ hash_clear(&sroutines); } else if (sroutines.records) { /* Non-zero sroutines.records means that hash was initialized. */ my_hash_reset(&sroutines); } sroutines_list.empty(); sroutines_list_own_last= sroutines_list.next; sroutines_list_own_elements= 0; } /* Destroy Query_tables_list object with freeing all resources used by it. SYNOPSIS destroy_query_tables_list() */ void Query_tables_list::destroy_query_tables_list() { hash_free(&sroutines); } /* Initialize LEX object. SYNOPSIS st_lex::st_lex() NOTE LEX object initialized with this constructor can be used as part of THD object for which one can safely call open_tables(), lock_tables() and close_thread_tables() functions. But it is not yet ready for statement parsing. On should use lex_start() function to prepare LEX for this. */ st_lex::st_lex() :result(0), yacc_yyss(0), yacc_yyvs(0), sql_command(SQLCOM_END) { reset_query_tables_list(TRUE); } /* Check whether the merging algorithm can be used on this VIEW SYNOPSIS st_lex::can_be_merged() DESCRIPTION We can apply merge algorithm if it is single SELECT view with subqueries only in WHERE clause (we do not count SELECTs of underlying views, and second level subqueries) and we have not grpouping, ordering, HAVING clause, aggregate functions, DISTINCT clause, LIMIT clause and several underlying tables. RETURN FALSE - only temporary table algorithm can be used TRUE - merge algorithm can be used */ bool st_lex::can_be_merged() { // TODO: do not forget implement case when select_lex.table_list.elements==0 /* find non VIEW subqueries/unions */ bool selects_allow_merge= select_lex.next_select() == 0; if (selects_allow_merge) { for (SELECT_LEX_UNIT *unit= select_lex.first_inner_unit(); unit; unit= unit->next_unit()) { if (unit->first_select()->parent_lex == this && (unit->item == 0 || (unit->item->place() != IN_WHERE && unit->item->place() != IN_ON))) { selects_allow_merge= 0; break; } } } return (selects_allow_merge && select_lex.order_list.elements == 0 && select_lex.group_list.elements == 0 && select_lex.having == 0 && select_lex.with_sum_func == 0 && select_lex.table_list.elements >= 1 && !(select_lex.options & SELECT_DISTINCT) && select_lex.select_limit == 0); } /* check if command can use VIEW with MERGE algorithm (for top VIEWs) SYNOPSIS st_lex::can_use_merged() DESCRIPTION Only listed here commands can use merge algorithm in top level SELECT_LEX (for subqueries will be used merge algorithm if st_lex::can_not_use_merged() is not TRUE). RETURN FALSE - command can't use merged VIEWs TRUE - VIEWs with MERGE algorithms can be used */ bool st_lex::can_use_merged() { switch (sql_command) { case SQLCOM_SELECT: case SQLCOM_CREATE_TABLE: case SQLCOM_UPDATE: case SQLCOM_UPDATE_MULTI: case SQLCOM_DELETE: case SQLCOM_DELETE_MULTI: case SQLCOM_INSERT: case SQLCOM_INSERT_SELECT: case SQLCOM_REPLACE: case SQLCOM_REPLACE_SELECT: case SQLCOM_LOAD: return TRUE; default: return FALSE; } } /* Check if command can't use merged views in any part of command SYNOPSIS st_lex::can_not_use_merged() DESCRIPTION Temporary table algorithm will be used on all SELECT levels for queries listed here (see also st_lex::can_use_merged()). RETURN FALSE - command can't use merged VIEWs TRUE - VIEWs with MERGE algorithms can be used */ bool st_lex::can_not_use_merged() { switch (sql_command) { case SQLCOM_CREATE_VIEW: case SQLCOM_SHOW_CREATE: /* SQLCOM_SHOW_FIELDS is necessary to make information schema tables working correctly with views. see get_schema_tables_result function */ case SQLCOM_SHOW_FIELDS: return TRUE; default: return FALSE; } } /* Detect that we need only table structure of derived table/view SYNOPSIS only_view_structure() RETURN TRUE yes, we need only structure FALSE no, we need data */ bool st_lex::only_view_structure() { switch (sql_command) { case SQLCOM_SHOW_CREATE: case SQLCOM_SHOW_TABLES: case SQLCOM_SHOW_FIELDS: case SQLCOM_REVOKE_ALL: case SQLCOM_REVOKE: case SQLCOM_GRANT: case SQLCOM_CREATE_VIEW: return TRUE; default: return FALSE; } } /* Should Items_ident be printed correctly SYNOPSIS need_correct_ident() RETURN TRUE yes, we need only structure FALSE no, we need data */ bool st_lex::need_correct_ident() { switch(sql_command) { case SQLCOM_SHOW_CREATE: case SQLCOM_SHOW_TABLES: case SQLCOM_CREATE_VIEW: return TRUE; default: return FALSE; } } /* Get effective type of CHECK OPTION for given view SYNOPSIS get_effective_with_check() view given view NOTE It have not sense to set CHECK OPTION for SELECT satement or subqueries, so we do not. RETURN VIEW_CHECK_NONE no need CHECK OPTION VIEW_CHECK_LOCAL CHECK OPTION LOCAL VIEW_CHECK_CASCADED CHECK OPTION CASCADED */ uint8 st_lex::get_effective_with_check(st_table_list *view) { if (view->select_lex->master_unit() == &unit && which_check_option_applicable()) return (uint8)view->with_check; return VIEW_CHECK_NONE; } /* initialize limit counters SYNOPSIS st_select_lex_unit::set_limit() values - SELECT_LEX with initial values for counters */ void st_select_lex_unit::set_limit(SELECT_LEX *sl) { ha_rows select_limit_val; DBUG_ASSERT(! thd->stmt_arena->is_stmt_prepare()); select_limit_val= (ha_rows)(sl->select_limit ? sl->select_limit->val_uint() : HA_POS_ERROR); offset_limit_cnt= (ha_rows)(sl->offset_limit ? sl->offset_limit->val_uint() : ULL(0)); select_limit_cnt= select_limit_val + offset_limit_cnt; if (select_limit_cnt < select_limit_val) select_limit_cnt= HA_POS_ERROR; // no limit } /* Unlink the first table from the global table list and the first table from outer select (lex->select_lex) local list SYNOPSIS unlink_first_table() link_to_local Set to 1 if caller should link this table to local list NOTES We assume that first tables in both lists is the same table or the local list is empty. RETURN 0 If 'query_tables' == 0 unlinked table In this case link_to_local is set. */ TABLE_LIST *st_lex::unlink_first_table(bool *link_to_local) { TABLE_LIST *first; if ((first= query_tables)) { /* Exclude from global table list */ if ((query_tables= query_tables->next_global)) query_tables->prev_global= &query_tables; else query_tables_last= &query_tables; first->next_global= 0; /* and from local list if it is not empty */ if ((*link_to_local= test(select_lex.table_list.first))) { select_lex.context.table_list= select_lex.context.first_name_resolution_table= first->next_local; select_lex.table_list.first= (byte*) (first->next_local); select_lex.table_list.elements--; //safety first->next_local= 0; /* Ensure that the global list has the same first table as the local list. */ first_lists_tables_same(); } } return first; } /* Bring first local table of first most outer select to first place in global table list SYNOPSYS st_lex::first_lists_tables_same() NOTES In many cases (for example, usual INSERT/DELETE/...) the first table of main SELECT_LEX have special meaning => check that it is the first table in global list and re-link to be first in the global list if it is necessary. We need such re-linking only for queries with sub-queries in the select list, as only in this case tables of sub-queries will go to the global list first. */ void st_lex::first_lists_tables_same() { TABLE_LIST *first_table= (TABLE_LIST*) select_lex.table_list.first; if (query_tables != first_table && first_table != 0) { TABLE_LIST *next; if (query_tables_last == &first_table->next_global) query_tables_last= first_table->prev_global; if ((next= *first_table->prev_global= first_table->next_global)) next->prev_global= first_table->prev_global; /* include in new place */ first_table->next_global= query_tables; /* We are sure that query_tables is not 0, because first_table was not first table in the global list => we can use query_tables->prev_global without check of query_tables */ query_tables->prev_global= &first_table->next_global; first_table->prev_global= &query_tables; query_tables= first_table; } } /* Add implicitly used time zone description tables to global table list (if needed). SYNOPSYS st_lex::add_time_zone_tables_to_query_tables() thd - pointer to current thread context RETURN VALUE TRUE - error FALSE - success */ bool st_lex::add_time_zone_tables_to_query_tables(THD *thd) { /* We should not add these tables twice */ if (!time_zone_tables_used) { time_zone_tables_used= my_tz_get_table_list(thd, &query_tables_last); if (time_zone_tables_used == &fake_time_zone_tables_list) return TRUE; } return FALSE; } /* Link table back that was unlinked with unlink_first_table() SYNOPSIS link_first_table_back() link_to_local do we need link this table to local RETURN global list */ void st_lex::link_first_table_back(TABLE_LIST *first, bool link_to_local) { if (first) { if ((first->next_global= query_tables)) query_tables->prev_global= &first->next_global; else query_tables_last= &first->next_global; query_tables= first; if (link_to_local) { first->next_local= (TABLE_LIST*) select_lex.table_list.first; select_lex.context.table_list= first; select_lex.table_list.first= (byte*) first; select_lex.table_list.elements++; //safety } } } /* cleanup lex for case when we open table by table for processing SYNOPSIS st_lex::cleanup_after_one_table_open() NOTE This method is mostly responsible for cleaning up of selects lists and derived tables state. To rollback changes in Query_tables_list one has to call Query_tables_list::reset_query_tables_list(FALSE). */ void st_lex::cleanup_after_one_table_open() { /* thd->lex->derived_tables & additional units may be set if we open a view. It is necessary to clear thd->lex->derived_tables flag to prevent processing of derived tables during next open_and_lock_tables if next table is a real table and cleanup & remove underlying units NOTE: all units will be connected to thd->lex->select_lex, because we have not UNION on most upper level. */ if (all_selects_list != &select_lex) { derived_tables= 0; /* cleunup underlying units (units of VIEW) */ for (SELECT_LEX_UNIT *un= select_lex.first_inner_unit(); un; un= un->next_unit()) un->cleanup(); /* reduce all selects list to default state */ all_selects_list= &select_lex; /* remove underlying units (units of VIEW) subtree */ select_lex.cut_subtree(); } time_zone_tables_used= 0; } /* Save current state of Query_tables_list for this LEX, and prepare it for processing of new statemnt. SYNOPSIS reset_n_backup_query_tables_list() backup Pointer to Query_tables_list instance to be used for backup */ void st_lex::reset_n_backup_query_tables_list(Query_tables_list *backup) { backup->set_query_tables_list(this); /* We have to perform full initialization here since otherwise we will damage backed up state. */ this->reset_query_tables_list(TRUE); } /* Restore state of Query_tables_list for this LEX from backup. SYNOPSIS restore_backup_query_tables_list() backup Pointer to Query_tables_list instance used for backup */ void st_lex::restore_backup_query_tables_list(Query_tables_list *backup) { this->destroy_query_tables_list(); this->set_query_tables_list(backup); } /* Do end-of-prepare fixup for list of tables and their merge-VIEWed tables SYNOPSIS fix_prepare_info_in_table_list() thd Thread handle tbl List of tables to process DESCRIPTION Perform end-end-of prepare fixup for list of tables, if any of the tables is a merge-algorithm VIEW, recursively fix up its underlying tables as well. */ static void fix_prepare_info_in_table_list(THD *thd, TABLE_LIST *tbl) { for (; tbl; tbl= tbl->next_local) { if (tbl->on_expr) { tbl->prep_on_expr= tbl->on_expr; tbl->on_expr= tbl->on_expr->copy_andor_structure(thd); } fix_prepare_info_in_table_list(thd, tbl->merge_underlying_list); } } /* Save WHERE/HAVING/ON clauses and replace them with disposable copies SYNOPSIS st_select_lex::fix_prepare_information thd thread handler conds in/out pointer to WHERE condition to be met at execution having_conds in/out pointer to HAVING condition to be met at execution DESCRIPTION The passed WHERE and HAVING are to be saved for the future executions. This function saves it, and returns a copy which can be thrashed during this execution of the statement. By saving/thrashing here we mean only AND/OR trees. The function also calls fix_prepare_info_in_table_list that saves all ON expressions. */ void st_select_lex::fix_prepare_information(THD *thd, Item **conds, Item **having_conds) { if (!thd->stmt_arena->is_conventional() && first_execution) { first_execution= 0; if (*conds) { prep_where= *conds; *conds= where= prep_where->copy_andor_structure(thd); } if (*having_conds) { prep_having= *having_conds; *having_conds= having= prep_having->copy_andor_structure(thd); } fix_prepare_info_in_table_list(thd, (TABLE_LIST *)table_list.first); } } /* There are st_select_lex::add_table_to_list & st_select_lex::set_lock_for_tables are in sql_parse.cc st_select_lex::print is in sql_select.cc st_select_lex_unit::prepare, st_select_lex_unit::exec, st_select_lex_unit::cleanup, st_select_lex_unit::reinit_exec_mechanism, st_select_lex_unit::change_result are in sql_union.cc */