1 /* Driver template for the LEMON parser generator.
2 ** The author disclaims copyright to this source code.
4 /* First off, code is include which follows the "include" declaration
5 ** in the input file. */
6 #include <lib-lib/lib-lib.h>
8 /* Next is all token values, in a form suitable for use by makeheaders.
9 ** This section will be null unless lemon is run with the -m switch.
12 ** These constants (all generated automatically by the parser generator)
13 ** specify the various kinds of tokens (terminals) that the parser
16 ** Each symbol here is a terminal symbol in the grammar.
19 /* Make sure the INTERFACE macro is defined.
24 /* The next thing included is series of defines which control
25 ** various aspects of the generated parser.
26 ** YYCODETYPE is the data type used for storing terminal
27 ** and nonterminal numbers. "unsigned char" is
28 ** used if there are fewer than 250 terminals
29 ** and nonterminals. "int" is used otherwise.
30 ** YYNOCODE is a number of type YYCODETYPE which corresponds
31 ** to no legal terminal or nonterminal number. This
32 ** number is used to fill in empty slots of the hash
34 ** YYFALLBACK If defined, this indicates that one or more tokens
35 ** have fall-back values which should be used if the
36 ** original value of the token will not parse.
37 ** YYACTIONTYPE is the data type used for storing terminal
38 ** and nonterminal numbers. "unsigned char" is
39 ** used if there are fewer than 250 rules and
40 ** states combined. "int" is used otherwise.
41 ** ParseTOKENTYPE is the data type used for minor tokens given
42 ** directly to the parser from the tokenizer.
43 ** YYMINORTYPE is the data type used for all minor tokens.
44 ** This is typically a union of many types, one of
45 ** which is ParseTOKENTYPE. The entry in the union
46 ** for base tokens is called "yy0".
47 ** YYSTACKDEPTH is the maximum depth of the parser's stack.
48 ** ParseARG_SDECL A static variable declaration for the %extra_argument
49 ** ParseARG_PDECL A parameter declaration for the %extra_argument
50 ** ParseARG_STORE Code to store %extra_argument into yypParser
51 ** ParseARG_FETCH Code to extract %extra_argument from yypParser
52 ** YYNSTATE the combined number of states.
53 ** YYNRULE the number of rules in the grammar
54 ** YYERRORSYMBOL is the code number of the error symbol. If not
55 ** defined, then do no error processing.
58 #define YY_NO_ACTION (YYNSTATE+YYNRULE+2)
59 #define YY_ACCEPT_ACTION (YYNSTATE+YYNRULE+1)
60 #define YY_ERROR_ACTION (YYNSTATE+YYNRULE)
62 /* Next are that tables used to determine what action to take based on the
63 ** current state and lookahead token. These tables are used to implement
64 ** functions that take a state number and lookahead value and return an
67 ** Suppose the action integer is N. Then the action is determined as
70 ** 0 <= N < YYNSTATE Shift N. That is, push the lookahead
71 ** token onto the stack and goto state N.
73 ** YYNSTATE <= N < YYNSTATE+YYNRULE Reduce by rule N-YYNSTATE.
75 ** N == YYNSTATE+YYNRULE A syntax error has occurred.
77 ** N == YYNSTATE+YYNRULE+1 The parser accepts its input.
79 ** N == YYNSTATE+YYNRULE+2 No such action. Denotes unused
80 ** slots in the yy_action[] table.
82 ** The action table is constructed as a single large table named yy_action[].
83 ** Given state S and lookahead X, the action is computed as
85 ** yy_action[ yy_shift_ofst[S] + X ]
87 ** If the index value yy_shift_ofst[S]+X is out of range or if the value
88 ** yy_lookahead[yy_shift_ofst[S]+X] is not equal to X or if yy_shift_ofst[S]
89 ** is equal to YY_SHIFT_USE_DFLT, it means that the action is not in the table
90 ** and that yy_default[S] should be used instead.
92 ** The formula above is for computing the action when the lookahead is
93 ** a terminal symbol. If the lookahead is a non-terminal (as occurs after
94 ** a reduce action) then the yy_reduce_ofst[] array is used in place of
95 ** the yy_shift_ofst[] array and YY_REDUCE_USE_DFLT is used in place of
98 ** The following are the tables generated in this section:
100 ** yy_action[] A single table containing all actions.
101 ** yy_lookahead[] A table containing the lookahead for each entry in
102 ** yy_action. Used to detect hash collisions.
103 ** yy_shift_ofst[] For each state, the offset into yy_action for
104 ** shifting terminals.
105 ** yy_reduce_ofst[] For each state, the offset into yy_action for
106 ** shifting non-terminals after a reduce.
107 ** yy_default[] Default action for each state.
110 #define YY_SZ_ACTTAB (int)(sizeof(yy_action)/sizeof(yy_action[0]))
112 /* The next table maps tokens into fallback tokens. If a construct
113 ** like the following:
115 ** %fallback ID X Y Z.
117 ** appears in the grammer, then ID becomes a fallback token for X, Y,
118 ** and Z. Whenever one of the tokens X, Y, or Z is input to the parser
119 ** but it does not parse, the type of the token is changed to ID and
120 ** the parse is retried before an error is thrown.
123 static const YYCODETYPE yyFallback[] = {
126 #endif /* YYFALLBACK */
128 /* The following structure represents a single element of the
129 ** parser's stack. Information stored includes:
131 ** + The state number for the parser at this level of the stack.
133 ** + The value of the token stored at this level of the stack.
134 ** (In other words, the "major" token.)
136 ** + The semantic value stored at this level of the stack. This is
137 ** the information used by the action routines in the grammar.
138 ** It is sometimes called the "minor" token.
140 struct yyStackEntry {
141 int stateno; /* The state-number */
142 int major; /* The major token value. This is the code
143 ** number for the token at this stack level */
144 YYMINORTYPE minor; /* The user-supplied minor token value. This
145 ** is the value of the token */
147 typedef struct yyStackEntry yyStackEntry;
149 /* The state of the parser is completely contained in an instance of
150 ** the following structure */
152 int yyidx; /* Index of top element in stack */
153 int yyerrcnt; /* Shifts left before out of the error */
154 ParseARG_SDECL /* A place to hold %extra_argument */
155 yyStackEntry yystack[YYSTACKDEPTH]; /* The parser's stack */
157 typedef struct yyParser yyParser;
161 static FILE *yyTraceFILE = 0;
162 static char *yyTracePrompt = 0;
167 ** Turn parser tracing on by giving a stream to which to write the trace
168 ** and a prompt to preface each trace message. Tracing is turned off
169 ** by making either argument NULL
173 ** <li> A FILE* to which trace output should be written.
174 ** If NULL, then tracing is turned off.
175 ** <li> A prefix string written at the beginning of every
176 ** line of trace output. If NULL, then tracing is
183 void ParseTrace(FILE *TraceFILE, char *zTracePrompt){
184 yyTraceFILE = TraceFILE;
185 yyTracePrompt = zTracePrompt;
186 if( yyTraceFILE==0 ) yyTracePrompt = 0;
187 else if( yyTracePrompt==0 ) yyTraceFILE = 0;
192 /* For tracing shifts, the names of all terminals and nonterminals
193 ** are required. The following table supplies these names */
194 static const char *const yyTokenName[] = {
200 /* For tracing reduce actions, the names of all rules are required.
202 static const char *const yyRuleName[] = {
208 ** This function returns the symbolic name associated with a token
211 const char *ParseTokenName(int tokenType){
213 if (tokenType>0 && tokenType < countof(yyTokenName)) {
214 return yyTokenName[tokenType];
224 ** This function allocates a new parser.
225 ** The only argument is a pointer to a function which works like
229 ** A pointer to the function used to allocate memory.
232 ** A pointer to a parser. This pointer is used in subsequent calls
233 ** to Parse and ParseFree.
235 void *ParseAlloc(void *(*mallocProc)(size_t)){
237 pParser = (yyParser*)(*mallocProc)( (size_t)sizeof(yyParser) );
244 /* The following function deletes the value associated with a
245 ** symbol. The symbol can be either a terminal or nonterminal.
246 ** "yymajor" is the symbol code, and "yypminor" is a pointer to
249 static void yy_destructor(YYCODETYPE yymajor, YYMINORTYPE *yypminor){
251 /* Here is inserted the actions which take place when a
252 ** terminal or non-terminal is destroyed. This can happen
253 ** when the symbol is popped from the stack during a
254 ** reduce or during error processing or when a parser is
255 ** being destroyed before it is finished parsing.
257 ** Note: during a reduce, the only symbols destroyed are those
258 ** which appear on the RHS of the rule, but which are not used
259 ** inside the C code.
262 default: break; /* If no destructor action specified: do nothing */
267 ** Pop the parser's stack once.
269 ** If there is a destructor routine associated with the token which
270 ** is popped from the stack, then call it.
272 ** Return the major token number for the symbol popped.
274 static int yy_pop_parser_stack(yyParser *pParser){
276 yyStackEntry *yytos = &pParser->yystack[pParser->yyidx];
278 if( pParser->yyidx<0 ) return 0;
280 if( yyTraceFILE && pParser->yyidx>=0 ){
281 fprintf(yyTraceFILE,"%sPopping %s\n",
283 yyTokenName[yytos->major]);
286 yymajor = yytos->major;
287 yy_destructor( yymajor, &yytos->minor);
293 ** Deallocate and destroy a parser. Destructors are all called for
294 ** all stack elements before shutting the parser down.
298 ** <li> A pointer to the parser. This should be a pointer
299 ** obtained from ParseAlloc.
300 ** <li> A pointer to a function used to reclaim memory obtained
305 void *p, /* The parser to be deleted */
306 void (*freeProc)(void*) /* Function used to reclaim memory */
308 yyParser *pParser = (yyParser*)p;
309 if( pParser==0 ) return;
310 while( pParser->yyidx>=0 ) yy_pop_parser_stack(pParser);
311 (*freeProc)((void*)pParser);
315 ** Find the appropriate action for a parser given the terminal
316 ** look-ahead token iLookAhead.
318 ** If the look-ahead token is YYNOCODE, then check to see if the action is
319 ** independent of the look-ahead. If it is, return the action, otherwise
320 ** return YY_NO_ACTION.
322 static int yy_find_shift_action(
323 yyParser *pParser, /* The parser */
324 YYCODETYPE iLookAhead /* The look-ahead token */
327 int stateno = pParser->yystack[pParser->yyidx].stateno;
329 if( stateno>YY_SHIFT_MAX || (i = yy_shift_ofst[stateno])==YY_SHIFT_USE_DFLT ){
330 return yy_default[stateno];
332 if( iLookAhead==YYNOCODE ){
336 if( i<0 || i>=YY_SZ_ACTTAB || yy_lookahead[i]!=iLookAhead ){
339 int iFallback; /* Fallback token */
340 if( iLookAhead<sizeof(yyFallback)/sizeof(yyFallback[0])
341 && (iFallback = yyFallback[iLookAhead])!=0 ){
344 fprintf(yyTraceFILE, "%sFALLBACK %s => %s\n",
345 yyTracePrompt, yyTokenName[iLookAhead], yyTokenName[iFallback]);
348 return yy_find_shift_action(pParser, iFallback);
353 int j = i - iLookAhead + YYWILDCARD;
354 if( j>=0 && j<YY_SZ_ACTTAB && yy_lookahead[j]==YYWILDCARD ){
357 fprintf(yyTraceFILE, "%sWILDCARD %s => %s\n",
358 yyTracePrompt, yyTokenName[iLookAhead], yyTokenName[YYWILDCARD]);
364 #endif /* YYWILDCARD */
366 return yy_default[stateno];
373 ** Find the appropriate action for a parser given the non-terminal
374 ** look-ahead token iLookAhead.
376 ** If the look-ahead token is YYNOCODE, then check to see if the action is
377 ** independent of the look-ahead. If it is, return the action, otherwise
378 ** return YY_NO_ACTION.
380 static int yy_find_reduce_action(
381 int stateno, /* Current state number */
382 YYCODETYPE iLookAhead /* The look-ahead token */
385 /* int stateno = pParser->yystack[pParser->yyidx].stateno; */
387 if( stateno>YY_REDUCE_MAX ||
388 (i = yy_reduce_ofst[stateno])==YY_REDUCE_USE_DFLT ){
389 return yy_default[stateno];
391 if( iLookAhead==YYNOCODE ){
395 if( i<0 || i>=YY_SZ_ACTTAB || yy_lookahead[i]!=iLookAhead ){
396 return yy_default[stateno];
403 ** Perform a shift action.
405 static void yy_shift(
406 yyParser *yypParser, /* The parser to be shifted */
407 int yyNewState, /* The new state to shift in */
408 int yyMajor, /* The major token to shift in */
409 YYMINORTYPE *yypMinor /* Pointer ot the minor token to shift in */
413 if( yypParser->yyidx>=YYSTACKDEPTH ){
418 fprintf(yyTraceFILE,"%sStack Overflow!\n",yyTracePrompt);
421 while( yypParser->yyidx>=0 ) yy_pop_parser_stack(yypParser);
422 /* Here code is inserted which will execute if the parser
423 ** stack every overflows */
425 ParseARG_STORE; /* Suppress warning about unused %extra_argument var */
428 yytos = &yypParser->yystack[yypParser->yyidx];
429 yytos->stateno = yyNewState;
430 yytos->major = yyMajor;
431 yytos->minor = *yypMinor;
433 if( yyTraceFILE && yypParser->yyidx>0 ){
435 fprintf(yyTraceFILE,"%sShift %d\n",yyTracePrompt,yyNewState);
436 fprintf(yyTraceFILE,"%sStack:",yyTracePrompt);
437 for(i=1; i<=yypParser->yyidx; i++)
438 fprintf(yyTraceFILE," %s",yyTokenName[yypParser->yystack[i].major]);
439 fprintf(yyTraceFILE,"\n");
444 /* The following table contains information about every rule that
445 ** is used during the reduce.
447 static const struct {
448 YYCODETYPE lhs; /* Symbol on the left-hand side of the rule */
449 unsigned char nrhs; /* Number of right-hand side symbols in the rule */
454 static void yy_accept(yyParser*); /* Forward Declaration */
457 ** Perform a reduce action and the shift that must immediately
458 ** follow the reduce.
460 static void yy_reduce(
461 yyParser *yypParser, /* The parser */
462 int yyruleno /* Number of the rule by which to reduce */
464 int yygoto; /* The next state */
465 int yyact; /* The next action */
466 YYMINORTYPE yygotominor; /* The LHS of the rule reduced */
467 yyStackEntry *yymsp; /* The top of the parser's stack */
468 int yysize; /* Amount to pop the stack */
470 yymsp = &yypParser->yystack[yypParser->yyidx];
472 if( yyTraceFILE && yyruleno>=0
473 && yyruleno<(int)(sizeof(yyRuleName)/sizeof(yyRuleName[0])) ){
474 fprintf(yyTraceFILE, "%sReduce [%s].\n", yyTracePrompt,
475 yyRuleName[yyruleno]);
480 /* Silence complaints from purify about yygotominor being uninitialized
481 ** in some cases when it is copied into the stack after the following
482 ** switch. yygotominor is uninitialized when a rule reduces that does
483 ** not set the value of its left-hand side nonterminal. Leaving the
484 ** value of the nonterminal uninitialized is utterly harmless as long
485 ** as the value is never used. So really the only thing this code
486 ** accomplishes is to quieten purify.
488 memset(&yygotominor, 0, sizeof(yygotominor));
492 /* Beginning here are the reduction cases. A typical example
495 ** #line <lineno> <grammarfile>
496 ** { ... } // User supplied code
497 ** #line <lineno> <thisfile>
502 yygoto = yyRuleInfo[yyruleno].lhs;
503 yysize = yyRuleInfo[yyruleno].nrhs;
504 yypParser->yyidx -= yysize;
505 yyact = yy_find_reduce_action(yymsp[-yysize].stateno,yygoto);
506 if( yyact < YYNSTATE ){
508 /* If we are not debugging and the reduce action popped at least
509 ** one element off the stack, then we can push the new element back
510 ** onto the stack here, and skip the stack overflow test in yy_shift().
511 ** That gives a significant speed improvement. */
515 yymsp->stateno = yyact;
516 yymsp->major = yygoto;
517 yymsp->minor = yygotominor;
521 yy_shift(yypParser,yyact,yygoto,&yygotominor);
523 }else if( yyact == YYNSTATE + YYNRULE + 1 ){
524 yy_accept(yypParser);
529 ** The following code executes when the parse fails
531 static void yy_parse_failed(
532 yyParser *yypParser /* The parser */
537 fprintf(yyTraceFILE,"%sFail!\n",yyTracePrompt);
540 while( yypParser->yyidx>=0 ) yy_pop_parser_stack(yypParser);
541 /* Here code is inserted which will be executed whenever the
544 ParseARG_STORE; /* Suppress warning about unused %extra_argument variable */
548 ** The following code executes when a syntax error first occurs.
550 static void yy_syntax_error(
551 yyParser *yypParser, /* The parser */
552 int yymajor __attribute__((unused)), /* The major type of the error token */
553 YYMINORTYPE yyminor __attribute__((unused))
554 /* The minor type of the error token */
557 #define TOKEN (yyminor.yy0)
559 ParseARG_STORE; /* Suppress warning about unused %extra_argument variable */
563 ** The following is executed when the parser accepts
565 static void yy_accept(
566 yyParser *yypParser /* The parser */
571 fprintf(yyTraceFILE,"%sAccept!\n",yyTracePrompt);
574 while( yypParser->yyidx>=0 ) yy_pop_parser_stack(yypParser);
575 /* Here code is inserted which will be executed whenever the
578 ParseARG_STORE; /* Suppress warning about unused %extra_argument variable */
581 /* The main parser program.
582 ** The first argument is a pointer to a structure obtained from
583 ** "ParseAlloc" which describes the current state of the parser.
584 ** The second argument is the major token number. The third is
585 ** the minor token. The fourth optional argument is whatever the
586 ** user wants (and specified in the grammar) and is available for
587 ** use by the action routines.
591 ** <li> A pointer to the parser (an opaque structure.)
592 ** <li> The major token number.
593 ** <li> The minor token number.
594 ** <li> An option argument of a grammar-specified type.
601 void *yyp, /* The parser */
602 int yymajor, /* The major token code number */
603 ParseTOKENTYPE yyminor /* The value for the token */
604 ParseARG_PDECL /* Optional %extra_argument parameter */
606 YYMINORTYPE yyminorunion;
607 int yyact; /* The parser action. */
608 int yyendofinput; /* True if we are at the end of input */
609 int yyerrorhit = 0; /* True if yymajor has invoked an error */
610 yyParser *yypParser; /* The parser */
612 /* (re)initialize the parser, if necessary */
613 yypParser = (yyParser*)yyp;
614 if( yypParser->yyidx<0 ){
615 /* if( yymajor==0 ) return; // not sure why this was here... */
616 yypParser->yyidx = 0;
617 yypParser->yyerrcnt = -1;
618 yypParser->yystack[0].stateno = 0;
619 yypParser->yystack[0].major = 0;
621 yyminorunion.yy0 = yyminor;
622 yyendofinput = (yymajor==0);
627 fprintf(yyTraceFILE,"%sInput %s\n",yyTracePrompt,yyTokenName[yymajor]);
632 yyact = yy_find_shift_action(yypParser,yymajor);
633 if( yyact<YYNSTATE ){
634 yy_shift(yypParser,yyact,yymajor,&yyminorunion);
635 yypParser->yyerrcnt--;
636 if( yyendofinput && yypParser->yyidx>=0 ){
641 }else if( yyact < YYNSTATE + YYNRULE ){
642 yy_reduce(yypParser,yyact-YYNSTATE);
643 }else if( yyact == YY_ERROR_ACTION ){
647 fprintf(yyTraceFILE,"%sSyntax Error!\n",yyTracePrompt);
651 /* A syntax error has occurred.
652 ** The response to an error depends upon whether or not the
653 ** grammar defines an error token "ERROR".
655 ** This is what we do if the grammar does define ERROR:
657 ** * Call the %syntax_error function.
659 ** * Begin popping the stack until we enter a state where
660 ** it is legal to shift the error symbol, then shift
663 ** * Set the error count to three.
665 ** * Begin accepting and shifting new tokens. No new error
666 ** processing will occur until three tokens have been
667 ** shifted successfully.
670 if( yypParser->yyerrcnt<0 ){
671 yy_syntax_error(yypParser,yymajor,yyminorunion);
673 yymx = yypParser->yystack[yypParser->yyidx].major;
674 if( yymx==YYERRORSYMBOL || yyerrorhit ){
677 fprintf(yyTraceFILE,"%sDiscard input token %s\n",
678 yyTracePrompt,yyTokenName[yymajor]);
681 yy_destructor(yymajor,&yyminorunion);
685 yypParser->yyidx >= 0 &&
686 yymx != YYERRORSYMBOL &&
687 (yyact = yy_find_reduce_action(
688 yypParser->yystack[yypParser->yyidx].stateno,
689 YYERRORSYMBOL)) >= YYNSTATE
691 yy_pop_parser_stack(yypParser);
693 if( yypParser->yyidx < 0 || yymajor==0 ){
694 yy_destructor(yymajor,&yyminorunion);
695 yy_parse_failed(yypParser);
697 }else if( yymx!=YYERRORSYMBOL ){
700 yy_shift(yypParser,yyact,YYERRORSYMBOL,&u2);
703 yypParser->yyerrcnt = 3;
705 #else /* YYERRORSYMBOL is not defined */
706 /* This is what we do if the grammar does not define ERROR:
708 ** * Report an error message, and throw away the input token.
710 ** * If the input token is $, then fail the parse.
712 ** As before, subsequent error messages are suppressed until
713 ** three input tokens have been successfully shifted.
715 if( yypParser->yyerrcnt<=0 ){
716 yy_syntax_error(yypParser,yymajor,yyminorunion);
718 yypParser->yyerrcnt = 3;
719 yy_destructor(yymajor,&yyminorunion);
721 yy_parse_failed(yypParser);
726 yy_accept(yypParser);
729 }while( yymajor!=YYNOCODE && yypParser->yyidx>=0 );