/* 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; 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 */ /* A lexical scanner on a temporary buffer with a yacc interface */ #include "mysql_priv.h" #include "item_create.h" #include <m_ctype.h> #include <hash.h> #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); /* Fake table list object, pointer to which is used as special value for st_lex::time_zone_tables_used indicating that we implicitly use time zone tables in this statement but real table list was not yet created. Pointer to it is also returned by my_tz_get_tables_list() as indication of transient error; */ TABLE_LIST fake_time_zone_tables_list; /* 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) #if MYSQL_VERSION_ID < 32300 #define FLOAT_NUM REAL_NUM #endif pthread_key(LEX*,THR_LEX); /* 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 */ 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); VOID(pthread_key_create(&THR_LEX,NULL)); 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; lex->thd= thd; lex->next_state=MY_LEX_START; lex->buf= lex->ptr= buf; lex->end_of_query=buf+length; 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->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=SQLCOM_END; lex->duplicates= DUP_ERROR; lex->sphead= NULL; lex->spcont= NULL; lex->trg_table= NULL; extern byte *sp_lex_spfuns_key(const byte *ptr, uint *plen, my_bool first); hash_free(&lex->spfuns); hash_init(&lex->spfuns, system_charset_info, 0, 0, 0, sp_lex_spfuns_key, 0, 0); } void lex_end(LEX *lex) { lex->select_lex.expr_list.delete_elements(); // If error when parsing sql-varargs x_free(lex->yacc_yyss); x_free(lex->yacc_yyvs); } 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; return symbol->tok; } return 0; } /* Check if name is a keyword SYNOPSIS is_keyword() name checked name 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) { 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 (*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; inline static 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 REAL_NUM; else { cmp=signed_longlong_str+1; smaller=LONG_NUM; // If <= signed_longlong_str bigger=REAL_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 REAL_NUM; cmp=unsigned_longlong_str; smaller=ULONGLONG_NUM; bigger=REAL_NUM; } else { cmp=longlong_str; smaller=LONG_NUM; bigger= ULONGLONG_NUM; } } while (*cmp && *cmp++ == *str++) ; return ((uchar) str[-1] <= (uchar) cmp[-1]) ? smaller : bigger; } /* yylex remember the following states from the following yylex() - 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 yylex(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_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 return((int) c); case MY_LEX_IDENT_OR_NCHAR: if (yyPeek() != '\'') { // Found x'hex-number' state= MY_LEX_IDENT; break; } yyGet(); // Skip ' while ((c = yyGet()) && (c !='\'')) ; length=(lex->ptr - lex->tok_start); // Length of hexnum+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 x' yylval->lex_str.length-=3; // Don't count x' and last ' lex->yytoklen-=3; return (NCHAR_STRING); case MY_LEX_IDENT_OR_HEX: if (yyPeek() == '\'') { // Found x'hex-number' state= MY_LEX_HEX_NUMBER; break; } /* Fall through */ case MY_LEX_IDENT_OR_BIN: // TODO: Add binary string handling case MY_LEX_IDENT: #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; if (lex->ignore_space) { for (; state_map[c] == MY_LEX_SKIP ; c= yyGet()); } if (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->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(); } // 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(REAL_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_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) && (thd->command != COM_PREPARE)) { lex->found_colon=(char*)lex->ptr; thd->server_status |= SERVER_MORE_RESULTS_EXISTS; lex->next_state=MY_LEX_END; return(END_OF_INPUT); } else 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 ((tokval= find_keyword(lex,length,0))) { yyUnget(); // Put back 'c' return(tokval); // Was keyword } yylval->lex_str=get_token(lex,length); return(result_state); } } } /* st_select_lex structures initialisations */ void st_select_lex_node::init_query() { options= 0; 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= 0; item_list.empty(); join= 0; where= prep_where= 0; olap= UNSPECIFIED_OLAP_TYPE; having_fix_field= 0; resolve_mode= NOMATTER_MODE; cond_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; first_execution= 1; first_cond_optimization= 1; parsing_place= NO_MATTER; no_wrap_view_item= 0; } void st_select_lex::init_select() { st_select_lex_node::init_select(); group_list.empty(); type= db= db1= table1= db2= table2= 0; having= 0; use_index_ptr= ignore_index_ptr= 0; table_join_options= 0; in_sum_expr= with_wild= 0; options= 0; braces= 0; when_list.empty(); expr_list.empty(); interval_list.empty(); use_index.empty(); ftfunc_list_alloc.empty(); ftfunc_list= &ftfunc_list_alloc; linkage= UNSPECIFIED_TYPE; order_list.elements= 0; order_list.first= 0; order_list.next= (byte**) &order_list.first; select_limit= HA_POS_ERROR; offset_limit= 0; with_sum_func= 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; } } 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<Item>* st_select_lex_node::get_item_list() { return 0; } List<String>* st_select_lex_node::get_use_index() { return 0; } List<String>* 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<String> *use_index, List<String> *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 != HA_POS_ERROR) { my_error(ER_NOT_SUPPORTED_YET, MYF(0), "LIMIT & IN/ALL/ANY/SOME subquery"); return(1); } // We need only 1 row to determinate existence select_limit= 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<Item>* st_select_lex::get_item_list() { return &item_list; } List<String>* st_select_lex::get_use_index() { return use_index_ptr; } List<String>* 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 */ Item_arena *arena= thd->current_arena; return (ref_pointer_array= (Item **)arena->alloc(sizeof(Item*) * (item_list.elements + select_n_having_items + order_group_num)* 5)) == 0; } /* Find db.table which will be updated in this unit SYNOPSIS st_select_lex_unit::check_updateable() db - data base name table - real table name RETURN 1 - found 0 - OK (table did not found) */ bool st_select_lex_unit::check_updateable(char *db, char *table) { for (SELECT_LEX *sl= first_select(); sl; sl= sl->next_select()) if (sl->check_updateable(db, table)) return 1; return 0; } /* Find db.table which will be updated in this select and underlayed ones (except derived tables) SYNOPSIS st_select_lex::check_updateable() db - data base name table - real table name RETURN 1 - found 0 - OK (table did not found) */ bool st_select_lex::check_updateable(char *db, char *table) { if (find_table_in_local_list(get_table_list(), db, table)) return 1; for (SELECT_LEX_UNIT *un= first_inner_unit(); un; un= un->next_unit()) { if (un->first_select()->linkage != DERIVED_TABLE_TYPE && un->check_updateable(db, table)) return 1; } return 0; } void st_select_lex_unit::print(String *str) { for (SELECT_LEX *sl= first_select(); sl; sl= sl->next_select()) { if (sl != first_select()) { str->append(" union ", 7); if (!union_distinct) str->append("all ", 4); } 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(" order by ", 10); 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]; my_snprintf(buffer, 20, "%u", order->counter); str->append(buffer); } else (*order->item)->print(str); if (!order->asc) str->append(" desc", 5); 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(select_limit == 1L && offset_limit == 0L); return; } if (!thd) thd= current_thd; if (explicit_limit) { str->append(" limit ", 7); char buff[20]; // latin1 is good enough for numbers String st(buff, sizeof(buff), &my_charset_latin1); st.set((ulonglong)select_limit, &my_charset_latin1); str->append(st); if (offset_limit) { str->append(','); st.set((ulonglong)select_limit, &my_charset_latin1); str->append(st); } } } /* 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)) { 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 == HA_POS_ERROR); } /* 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: 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: 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; } } /* initialize limit counters SYNOPSIS st_select_lex_unit::set_limit() values - SELECT_LEX with initial values for counters sl - SELECT_LEX for options set */ void st_select_lex_unit::set_limit(SELECT_LEX *values, SELECT_LEX *sl) { offset_limit_cnt= values->offset_limit; select_limit_cnt= values->select_limit+values->offset_limit; if (select_limit_cnt < values->select_limit) select_limit_cnt= HA_POS_ERROR; // no limit if (select_limit_cnt == HA_POS_ERROR) sl->options&= ~OPTION_FOUND_ROWS; } /* 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; 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.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; } } /* 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; query_tables= first; if (link_to_local) { first->next_local= (TABLE_LIST*) select_lex.table_list.first; select_lex.table_list.first= (byte*) first; select_lex.table_list.elements++; //safety } } } /* fix some structures at the end of preparation SYNOPSIS st_select_lex::fix_prepare_information thd thread handler conds pointer on conditions which will be used for execution statement */ void st_select_lex::fix_prepare_information(THD *thd, Item **conds) { if (!thd->current_arena->is_conventional() && first_execution) { first_execution= 0; prep_where= where; } } /* 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 */