/* Driver template for the LEMON parser generator. ** Copyright 1991-1995 by D. Richard Hipp. * * This version is specially modified for use with sqlite. * @(#) $Id: lempar.c,v 1.1 2000/05/29 14:26:02 drh Exp $ * ** ** This library is free software; you can redistribute it and/or ** modify it under the terms of the GNU Library General Public ** License as published by the Free Software Foundation; either ** version 2 of the License, or (at your option) any later version. ** ** This library 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 ** Library General Public License for more details. ** ** You should have received a copy of the GNU Library General Public ** License along with this library; if not, write to the ** Free Software Foundation, Inc., 59 Temple Place - Suite 330, ** Boston, MA 02111-1307, USA. ** ** Modified 1997 to make it suitable for use with makeheaders. */ /* First off, code is include which follows the "include" declaration ** in the input file. */ #include %% /* Next is all token values, in a form suitable for use by makeheaders. ** This section will be null unless lemon is run with the -m switch. */ /* ** These constants (all generated automatically by the parser generator) ** specify the various kinds of tokens (terminals) that the parser ** understands. ** ** Each symbol here is a terminal symbol in the grammar. */ %% /* Make sure the INTERFACE macro is defined. */ #ifndef INTERFACE # define INTERFACE 1 #endif /* The next thing included is series of defines which control ** various aspects of the generated parser. ** YYCODETYPE is the data type used for storing terminal ** and nonterminal numbers. "unsigned char" is ** used if there are fewer than 250 terminals ** and nonterminals. "int" is used otherwise. ** YYNOCODE is a number of type YYCODETYPE which corresponds ** to no legal terminal or nonterminal number. This ** number is used to fill in empty slots of the hash ** table. ** YYACTIONTYPE is the data type used for storing terminal ** and nonterminal numbers. "unsigned char" is ** used if there are fewer than 250 rules and ** states combined. "int" is used otherwise. ** ParseTOKENTYPE is the data type used for minor tokens given ** directly to the parser from the tokenizer. ** YYMINORTYPE is the data type used for all minor tokens. ** This is typically a union of many types, one of ** which is ParseTOKENTYPE. The entry in the union ** for base tokens is called "yy0". ** YYSTACKDEPTH is the maximum depth of the parser's stack. ** ParseARGDECL is a declaration of a 3rd argument to the ** parser, or null if there is no extra argument. ** ParseKRARGDECL A version of ParseARGDECL for K&R C. ** ParseANSIARGDECL A version of ParseARGDECL for ANSI C. ** YYNSTATE the combined number of states. ** YYNRULE the number of rules in the grammar ** YYERRORSYMBOL is the code number of the error symbol. If not ** defined, then do no error processing. */ %% #define YY_NO_ACTION (YYNSTATE+YYNRULE+2) #define YY_ACCEPT_ACTION (YYNSTATE+YYNRULE+1) #define YY_ERROR_ACTION (YYNSTATE+YYNRULE) /* Next is the action table. Each entry in this table contains ** ** + An integer which is the number representing the look-ahead ** token ** ** + An integer indicating what action to take. Number (N) between ** 0 and YYNSTATE-1 mean shift the look-ahead and go to state N. ** Numbers between YYNSTATE and YYNSTATE+YYNRULE-1 mean reduce by ** rule N-YYNSTATE. Number YYNSTATE+YYNRULE means that a syntax ** error has occurred. Number YYNSTATE+YYNRULE+1 means the parser ** accepts its input. ** ** + A pointer to the next entry with the same hash value. ** ** The action table is really a series of hash tables. Each hash ** table contains a number of entries which is a power of two. The ** "state" table (which follows) contains information about the starting ** point and size of each hash table. */ struct yyActionEntry { YYCODETYPE lookahead; /* The value of the look-ahead token */ YYACTIONTYPE action; /* Action to take for this look-ahead */ struct yyActionEntry *next; /* Next look-ahead with the same hash, or NULL */ }; static struct yyActionEntry yyActionTable[] = { %% }; /* The state table contains information needed to look up the correct ** action in the action table, given the current state of the parser. ** Information needed includes: ** ** + A pointer to the start of the action hash table in yyActionTable. ** ** + A mask used to hash the look-ahead token. The mask is an integer ** which is one less than the size of the hash table. ** ** + The default action. This is the action to take if no entry for ** the given look-ahead is found in the action hash table. */ struct yyStateEntry { struct yyActionEntry *hashtbl; /* Start of the hash table in yyActionTable */ int mask; /* Mask used for hashing the look-ahead */ YYACTIONTYPE actionDefault; /* Default action if look-ahead not found */ }; static struct yyStateEntry yyStateTable[] = { %% }; /* The following structure represents a single element of the ** parser's stack. Information stored includes: ** ** + The state number for the parser at this level of the stack. ** ** + The value of the token stored at this level of the stack. ** (In other words, the "major" token.) ** ** + The semantic value stored at this level of the stack. This is ** the information used by the action routines in the grammar. ** It is sometimes called the "minor" token. */ struct yyStackEntry { int stateno; /* The state-number */ int major; /* The major token value. This is the code ** number for the token at this stack level */ YYMINORTYPE minor; /* The user-supplied minor token value. This ** is the value of the token */ }; /* The state of the parser is completely contained in an instance of ** the following structure */ struct yyParser { int idx; /* Index of top element in stack */ int errcnt; /* Shifts left before out of the error */ struct yyStackEntry *top; /* Pointer to the top stack element */ struct yyStackEntry stack[YYSTACKDEPTH]; /* The parser's stack */ }; typedef struct yyParser yyParser; #ifndef NDEBUG #include static FILE *yyTraceFILE = 0; static char *yyTracePrompt = 0; /* ** Turn parser tracing on by giving a stream to which to write the trace ** and a prompt to preface each trace message. Tracing is turned off ** by making either argument NULL ** ** Inputs: ** ** ** Outputs: ** None. */ /* SQLITE MODIFICATION: Give the function file scope */ void ParseTrace(FILE *TraceFILE, char *zTracePrompt){ yyTraceFILE = TraceFILE; yyTracePrompt = zTracePrompt; if( yyTraceFILE==0 ) yyTracePrompt = 0; else if( yyTracePrompt==0 ) yyTraceFILE = 0; } /* For tracing shifts, the names of all terminals and nonterminals ** are required. The following table supplies these names */ static char *yyTokenName[] = { %% }; #define YYTRACE(X) if( yyTraceFILE ) fprintf(yyTraceFILE,"%sReduce [%s].\n",yyTracePrompt,X); #else #define YYTRACE(X) #endif /* ** This function allocates a new parser. ** The only argument is a pointer to a function which works like ** malloc. ** ** Inputs: ** A pointer to the function used to allocate memory. ** ** Outputs: ** A pointer to a parser. This pointer is used in subsequent calls ** to Parse and ParseFree. */ /* SQLITE MODIFICATION: Give the function file scope */ void *ParseAlloc(void *(*mallocProc)()){ yyParser *pParser; pParser = (yyParser*)(*mallocProc)( sizeof(yyParser), __FILE__, __LINE__ ); if( pParser ){ pParser->idx = -1; } return pParser; } /* The following function deletes the value associated with a ** symbol. The symbol can be either a terminal or nonterminal. ** "yymajor" is the symbol code, and "yypminor" is a pointer to ** the value. */ static void yy_destructor(YYCODETYPE yymajor, YYMINORTYPE *yypminor){ switch( yymajor ){ /* Here is inserted the actions which take place when a ** terminal or non-terminal is destroyed. This can happen ** when the symbol is popped from the stack during a ** reduce or during error processing or when a parser is ** being destroyed before it is finished parsing. ** ** Note: during a reduce, the only symbols destroyed are those ** which appear on the RHS of the rule, but which are not used ** inside the C code. */ %% default: break; /* If no destructor action specified: do nothing */ } } /* ** Pop the parser's stack once. ** ** If there is a destructor routine associated with the token which ** is popped from the stack, then call it. ** ** Return the major token number for the symbol popped. */ static int yy_pop_parser_stack(yyParser *pParser){ YYCODETYPE yymajor; if( pParser->idx<0 ) return 0; #ifndef NDEBUG if( yyTraceFILE && pParser->idx>=0 ){ fprintf(yyTraceFILE,"%sPopping %s\n", yyTracePrompt, yyTokenName[pParser->top->major]); } #endif yymajor = pParser->top->major; yy_destructor( yymajor, &pParser->top->minor); pParser->idx--; pParser->top--; return yymajor; } /* ** Deallocate and destroy a parser. Destructors are all called for ** all stack elements before shutting the parser down. ** ** Inputs: ** */ /* SQLITE MODIFICATION: Give the function file scope */ void ParseFree( void *p, /* The parser to be deleted */ void (*freeProc)() /* Function used to reclaim memory */ ){ yyParser *pParser = (yyParser*)p; if( pParser==0 ) return; while( pParser->idx>=0 ) yy_pop_parser_stack(pParser); (*freeProc)(pParser, __FILE__, __LINE__); } /* ** Find the appropriate action for a parser given the look-ahead token. ** ** If the look-ahead token is YYNOCODE, then check to see if the action is ** independent of the look-ahead. If it is, return the action, otherwise ** return YY_NO_ACTION. */ static int yy_find_parser_action( yyParser *pParser, /* The parser */ int iLookAhead /* The look-ahead token */ ){ struct yyStateEntry *pState; /* Appropriate entry in the state table */ struct yyActionEntry *pAction; /* Action appropriate for the look-ahead */ /* if( pParser->idx<0 ) return YY_NO_ACTION; */ pState = &yyStateTable[pParser->top->stateno]; if( iLookAhead!=YYNOCODE ){ pAction = &pState->hashtbl[iLookAhead & pState->mask]; while( pAction ){ if( pAction->lookahead==iLookAhead ) return pAction->action; pAction = pAction->next; } }else if( pState->mask!=0 || pState->hashtbl->lookahead!=YYNOCODE ){ return YY_NO_ACTION; } return pState->actionDefault; } /* ** Perform a shift action. */ static void yy_shift( yyParser *yypParser, /* The parser to be shifted */ int yyNewState, /* The new state to shift in */ int yyMajor, /* The major token to shift in */ YYMINORTYPE *yypMinor /* Pointer ot the minor token to shift in */ ){ yypParser->idx++; yypParser->top++; if( yypParser->idx>=YYSTACKDEPTH ){ yypParser->idx--; yypParser->top--; #ifndef NDEBUG if( yyTraceFILE ){ fprintf(yyTraceFILE,"%sStack Overflow!\n",yyTracePrompt); } #endif while( yypParser->idx>=0 ) yy_pop_parser_stack(yypParser); /* Here code is inserted which will execute if the parser ** stack every overflows */ %% return; } yypParser->top->stateno = yyNewState; yypParser->top->major = yyMajor; yypParser->top->minor = *yypMinor; #ifndef NDEBUG if( yyTraceFILE && yypParser->idx>0 ){ int i; fprintf(yyTraceFILE,"%sShift %d\n",yyTracePrompt,yyNewState); fprintf(yyTraceFILE,"%sStack:",yyTracePrompt); for(i=1; i<=yypParser->idx; i++) fprintf(yyTraceFILE," %s",yyTokenName[yypParser->stack[i].major]); fprintf(yyTraceFILE,"\n"); } #endif } /* The following table contains information about every rule that ** is used during the reduce. */ static struct { YYCODETYPE lhs; /* Symbol on the left-hand side of the rule */ unsigned char nrhs; /* Number of right-hand side symbols in the rule */ } yyRuleInfo[] = { %% }; static void yy_accept(); /* Forward declaration */ /* ** Perform a reduce action and the shift that must immediately ** follow the reduce. */ static void yy_reduce( yyParser *yypParser, /* The parser */ int yyruleno /* Number of the rule by which to reduce */ ParseANSIARGDECL ){ int yygoto; /* The next state */ int yyact; /* The next action */ YYMINORTYPE yygotominor; /* The LHS of the rule reduced */ struct yyStackEntry *yymsp; /* The top of the parser's stack */ int yysize; /* Amount to pop the stack */ yymsp = yypParser->top; switch( yyruleno ){ /* Beginning here are the reduction cases. A typical example ** follows: ** case 0: ** YYTRACE(""); ** #line ** { ... } // User supplied code ** #line ** break; */ %% }; yygoto = yyRuleInfo[yyruleno].lhs; yysize = yyRuleInfo[yyruleno].nrhs; yypParser->idx -= yysize; yypParser->top -= yysize; yyact = yy_find_parser_action(yypParser,yygoto); if( yyact < YYNSTATE ){ yy_shift(yypParser,yyact,yygoto,&yygotominor); }else if( yyact == YYNSTATE + YYNRULE + 1 ){ yy_accept(yypParser ParseARGDECL); } } /* ** The following code executes when the parse fails */ static void yy_parse_failed( yyParser *yypParser /* The parser */ ParseANSIARGDECL /* Extra arguments (if any) */ ){ #ifndef NDEBUG if( yyTraceFILE ){ fprintf(yyTraceFILE,"%sFail!\n",yyTracePrompt); } #endif while( yypParser->idx>=0 ) yy_pop_parser_stack(yypParser); /* Here code is inserted which will be executed whenever the ** parser fails */ %% } /* ** The following code executes when a syntax error first occurs. */ static void yy_syntax_error( yyParser *yypParser, /* The parser */ int yymajor, /* The major type of the error token */ YYMINORTYPE yyminor /* The minor type of the error token */ ParseANSIARGDECL /* Extra arguments (if any) */ ){ #define TOKEN (yyminor.yy0) %% } /* ** The following is executed when the parser accepts */ static void yy_accept( yyParser *yypParser /* The parser */ ParseANSIARGDECL /* Extra arguments (if any) */ ){ #ifndef NDEBUG if( yyTraceFILE ){ fprintf(yyTraceFILE,"%sAccept!\n",yyTracePrompt); } #endif while( yypParser->idx>=0 ) yy_pop_parser_stack(yypParser); /* Here code is inserted which will be executed whenever the ** parser accepts */ %% } /* The main parser program. ** The first argument is a pointer to a structure obtained from ** "ParseAlloc" which describes the current state of the parser. ** The second argument is the major token number. The third is ** the minor token. The fourth optional argument is whatever the ** user wants (and specified in the grammar) and is available for ** use by the action routines. ** ** Inputs: **
    **
  • A pointer to the parser (an opaque structure.) **
  • The major token number. **
  • The minor token number. **
  • An option argument of a grammar-specified type. **
** ** Outputs: ** None. */ /* SQLITE MODIFICATION: Give the function file scope */ void Parse( void *yyp, /* The parser */ int yymajor, /* The major token code number */ ParseTOKENTYPE yyminor /* The value for the token */ ParseANSIARGDECL ){ YYMINORTYPE yyminorunion; int yyact; /* The parser action. */ int yyendofinput; /* True if we are at the end of input */ int yyerrorhit = 0; /* True if yymajor has invoked an error */ yyParser *yypParser; /* The parser */ /* (re)initialize the parser, if necessary */ yypParser = (yyParser*)yyp; if( yypParser->idx<0 ){ if( yymajor==0 ) return; yypParser->idx = 0; yypParser->errcnt = -1; yypParser->top = &yypParser->stack[0]; yypParser->top->stateno = 0; yypParser->top->major = 0; } yyminorunion.yy0 = yyminor; yyendofinput = (yymajor==0); #ifndef NDEBUG if( yyTraceFILE ){ fprintf(yyTraceFILE,"%sInput %s\n",yyTracePrompt,yyTokenName[yymajor]); } #endif do{ yyact = yy_find_parser_action(yypParser,yymajor); if( yyacterrcnt--; if( yyendofinput && yypParser->idx>=0 ){ yymajor = 0; }else{ yymajor = YYNOCODE; } }else if( yyact < YYNSTATE + YYNRULE ){ yy_reduce(yypParser,yyact-YYNSTATE ParseARGDECL); }else if( yyact == YY_ERROR_ACTION ){ #ifndef NDEBUG if( yyTraceFILE ){ fprintf(yyTraceFILE,"%sSyntax Error!\n",yyTracePrompt); } #endif #ifdef YYERRORSYMBOL /* A syntax error has occurred. ** The response to an error depends upon whether or not the ** grammar defines an error token "ERROR". ** ** This is what we do if the grammar does define ERROR: ** ** * Call the %syntax_error function. ** ** * Begin popping the stack until we enter a state where ** it is legal to shift the error symbol, then shift ** the error symbol. ** ** * Set the error count to three. ** ** * Begin accepting and shifting new tokens. No new error ** processing will occur until three tokens have been ** shifted successfully. ** */ if( yypParser->errcnt<0 ){ yy_syntax_error(yypParser,yymajor,yyminorunion ParseARGDECL); } if( yypParser->top->major==YYERRORSYMBOL || yyerrorhit ){ #ifndef NDEBUG if( yyTraceFILE ){ fprintf(yyTraceFILE,"%sDiscard input token %s\n", yyTracePrompt,yyTokenName[yymajor]); } #endif yy_destructor(yymajor,&yyminorunion); yymajor = YYNOCODE; }else{ while( yypParser->idx >= 0 && yypParser->top->major != YYERRORSYMBOL && (yyact = yy_find_parser_action(yypParser,YYERRORSYMBOL)) >= YYNSTATE ){ yy_pop_parser_stack(yypParser); } if( yypParser->idx < 0 || yymajor==0 ){ yy_destructor(yymajor,&yyminorunion); yy_parse_failed(yypParser ParseARGDECL); yymajor = YYNOCODE; }else if( yypParser->top->major!=YYERRORSYMBOL ){ YYMINORTYPE u2; u2.YYERRSYMDT = 0; yy_shift(yypParser,yyact,YYERRORSYMBOL,&u2); } } yypParser->errcnt = 3; yyerrorhit = 1; #else /* YYERRORSYMBOL is not defined */ /* This is what we do if the grammar does not define ERROR: ** ** * Report an error message, and throw away the input token. ** ** * If the input token is $, then fail the parse. ** ** As before, subsequent error messages are suppressed until ** three input tokens have been successfully shifted. */ if( yypParser->errcnt<=0 ){ yy_syntax_error(yypParser,yymajor,yyminorunion ParseARGDECL); } yypParser->errcnt = 3; yy_destructor(yymajor,&yyminorunion); if( yyendofinput ){ yy_parse_failed(yypParser ParseARGDECL); } yymajor = YYNOCODE; #endif }else{ yy_accept(yypParser ParseARGDECL); yymajor = YYNOCODE; } }while( yymajor!=YYNOCODE && yypParser->idx>=0 ); return; }