X-Git-Url: http://git.madism.org/?a=blobdiff_plain;f=tools%2Flempar.c;fp=tools%2Flempar.c;h=168efc4655f3e7e20ad14e8158b28603d71e285b;hb=c19619baf50f0cb708f271e3b342249d0477ffa4;hp=0000000000000000000000000000000000000000;hpb=643b8bf1557f533756a5563ff1e5c416561c58ed;p=apps%2Fmadmutt.git diff --git a/tools/lempar.c b/tools/lempar.c new file mode 100644 index 0000000..168efc4 --- /dev/null +++ b/tools/lempar.c @@ -0,0 +1,730 @@ +/* Driver template for the LEMON parser generator. +** The author disclaims copyright to this source code. +*/ +/* 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. +** YYFALLBACK If defined, this indicates that one or more tokens +** have fall-back values which should be used if the +** original value of the token will not parse. +** 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. +** ParseARG_SDECL A static variable declaration for the %extra_argument +** ParseARG_PDECL A parameter declaration for the %extra_argument +** ParseARG_STORE Code to store %extra_argument into yypParser +** ParseARG_FETCH Code to extract %extra_argument from yypParser +** 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 are that tables used to determine what action to take based on the +** current state and lookahead token. These tables are used to implement +** functions that take a state number and lookahead value and return an +** action integer. +** +** Suppose the action integer is N. Then the action is determined as +** follows +** +** 0 <= N < YYNSTATE Shift N. That is, push the lookahead +** token onto the stack and goto state N. +** +** YYNSTATE <= N < YYNSTATE+YYNRULE Reduce by rule N-YYNSTATE. +** +** N == YYNSTATE+YYNRULE A syntax error has occurred. +** +** N == YYNSTATE+YYNRULE+1 The parser accepts its input. +** +** N == YYNSTATE+YYNRULE+2 No such action. Denotes unused +** slots in the yy_action[] table. +** +** The action table is constructed as a single large table named yy_action[]. +** Given state S and lookahead X, the action is computed as +** +** yy_action[ yy_shift_ofst[S] + X ] +** +** If the index value yy_shift_ofst[S]+X is out of range or if the value +** yy_lookahead[yy_shift_ofst[S]+X] is not equal to X or if yy_shift_ofst[S] +** is equal to YY_SHIFT_USE_DFLT, it means that the action is not in the table +** and that yy_default[S] should be used instead. +** +** The formula above is for computing the action when the lookahead is +** a terminal symbol. If the lookahead is a non-terminal (as occurs after +** a reduce action) then the yy_reduce_ofst[] array is used in place of +** the yy_shift_ofst[] array and YY_REDUCE_USE_DFLT is used in place of +** YY_SHIFT_USE_DFLT. +** +** The following are the tables generated in this section: +** +** yy_action[] A single table containing all actions. +** yy_lookahead[] A table containing the lookahead for each entry in +** yy_action. Used to detect hash collisions. +** yy_shift_ofst[] For each state, the offset into yy_action for +** shifting terminals. +** yy_reduce_ofst[] For each state, the offset into yy_action for +** shifting non-terminals after a reduce. +** yy_default[] Default action for each state. +*/ +%% +#define YY_SZ_ACTTAB (int)(sizeof(yy_action)/sizeof(yy_action[0])) + +/* The next table maps tokens into fallback tokens. If a construct +** like the following: +** +** %fallback ID X Y Z. +** +** appears in the grammer, then ID becomes a fallback token for X, Y, +** and Z. Whenever one of the tokens X, Y, or Z is input to the parser +** but it does not parse, the type of the token is changed to ID and +** the parse is retried before an error is thrown. +*/ +#ifdef YYFALLBACK +static const YYCODETYPE yyFallback[] = { +%% +}; +#endif /* YYFALLBACK */ + +/* 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 */ +}; +typedef struct yyStackEntry yyStackEntry; + +/* The state of the parser is completely contained in an instance of +** the following structure */ +struct yyParser { + int yyidx; /* Index of top element in stack */ + int yyerrcnt; /* Shifts left before out of the error */ + ParseARG_SDECL /* A place to hold %extra_argument */ + yyStackEntry yystack[YYSTACKDEPTH]; /* The parser's stack */ +}; +typedef struct yyParser yyParser; + +#ifndef NDEBUG +#include +static FILE *yyTraceFILE = 0; +static char *yyTracePrompt = 0; +#endif /* NDEBUG */ + +#ifndef NDEBUG +/* +** 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. +*/ +void ParseTrace(FILE *TraceFILE, char *zTracePrompt){ + yyTraceFILE = TraceFILE; + yyTracePrompt = zTracePrompt; + if( yyTraceFILE==0 ) yyTracePrompt = 0; + else if( yyTracePrompt==0 ) yyTraceFILE = 0; +} +#endif /* NDEBUG */ + +#ifndef NDEBUG +/* For tracing shifts, the names of all terminals and nonterminals +** are required. The following table supplies these names */ +static const char *const yyTokenName[] = { +%% +}; +#endif /* NDEBUG */ + +#ifndef NDEBUG +/* For tracing reduce actions, the names of all rules are required. +*/ +static const char *const yyRuleName[] = { +%% +}; +#endif /* NDEBUG */ + +/* +** This function returns the symbolic name associated with a token +** value. +*/ +const char *ParseTokenName(int tokenType){ +#ifndef NDEBUG + if (tokenType>0 && tokenType < countof(yyTokenName)) { + return yyTokenName[tokenType]; + }else{ + return "Unknown"; + } +#else + return ""; +#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. +*/ +void *ParseAlloc(void *(*mallocProc)(size_t)){ + yyParser *pParser; + pParser = (yyParser*)(*mallocProc)( (size_t)sizeof(yyParser) ); + if( pParser ){ + pParser->yyidx = -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; + yyStackEntry *yytos = &pParser->yystack[pParser->yyidx]; + + if( pParser->yyidx<0 ) return 0; +#ifndef NDEBUG + if( yyTraceFILE && pParser->yyidx>=0 ){ + fprintf(yyTraceFILE,"%sPopping %s\n", + yyTracePrompt, + yyTokenName[yytos->major]); + } +#endif + yymajor = yytos->major; + yy_destructor( yymajor, &yytos->minor); + pParser->yyidx--; + return yymajor; +} + +/* +** Deallocate and destroy a parser. Destructors are all called for +** all stack elements before shutting the parser down. +** +** Inputs: +** +*/ +void ParseFree( + void *p, /* The parser to be deleted */ + void (*freeProc)(void*) /* Function used to reclaim memory */ +){ + yyParser *pParser = (yyParser*)p; + if( pParser==0 ) return; + while( pParser->yyidx>=0 ) yy_pop_parser_stack(pParser); + (*freeProc)((void*)pParser); +} + +/* +** Find the appropriate action for a parser given the terminal +** look-ahead token iLookAhead. +** +** 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_shift_action( + yyParser *pParser, /* The parser */ + YYCODETYPE iLookAhead /* The look-ahead token */ +){ + int i; + int stateno = pParser->yystack[pParser->yyidx].stateno; + + if( stateno>YY_SHIFT_MAX || (i = yy_shift_ofst[stateno])==YY_SHIFT_USE_DFLT ){ + return yy_default[stateno]; + } + if( iLookAhead==YYNOCODE ){ + return YY_NO_ACTION; + } + i += iLookAhead; + if( i<0 || i>=YY_SZ_ACTTAB || yy_lookahead[i]!=iLookAhead ){ + if( iLookAhead>0 ){ +#ifdef YYFALLBACK + int iFallback; /* Fallback token */ + if( iLookAhead %s\n", + yyTracePrompt, yyTokenName[iLookAhead], yyTokenName[iFallback]); + } +#endif + return yy_find_shift_action(pParser, iFallback); + } +#endif +#ifdef YYWILDCARD + { + int j = i - iLookAhead + YYWILDCARD; + if( j>=0 && j %s\n", + yyTracePrompt, yyTokenName[iLookAhead], yyTokenName[YYWILDCARD]); + } +#endif /* NDEBUG */ + return yy_action[j]; + } + } +#endif /* YYWILDCARD */ + } + return yy_default[stateno]; + }else{ + return yy_action[i]; + } +} + +/* +** Find the appropriate action for a parser given the non-terminal +** look-ahead token iLookAhead. +** +** 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_reduce_action( + int stateno, /* Current state number */ + YYCODETYPE iLookAhead /* The look-ahead token */ +){ + int i; + /* int stateno = pParser->yystack[pParser->yyidx].stateno; */ + + if( stateno>YY_REDUCE_MAX || + (i = yy_reduce_ofst[stateno])==YY_REDUCE_USE_DFLT ){ + return yy_default[stateno]; + } + if( iLookAhead==YYNOCODE ){ + return YY_NO_ACTION; + } + i += iLookAhead; + if( i<0 || i>=YY_SZ_ACTTAB || yy_lookahead[i]!=iLookAhead ){ + return yy_default[stateno]; + }else{ + return yy_action[i]; + } +} + +/* +** 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 */ +){ + yyStackEntry *yytos; + yypParser->yyidx++; + if( yypParser->yyidx>=YYSTACKDEPTH ){ + ParseARG_FETCH; + yypParser->yyidx--; +#ifndef NDEBUG + if( yyTraceFILE ){ + fprintf(yyTraceFILE,"%sStack Overflow!\n",yyTracePrompt); + } +#endif + while( yypParser->yyidx>=0 ) yy_pop_parser_stack(yypParser); + /* Here code is inserted which will execute if the parser + ** stack every overflows */ +%% + ParseARG_STORE; /* Suppress warning about unused %extra_argument var */ + return; + } + yytos = &yypParser->yystack[yypParser->yyidx]; + yytos->stateno = yyNewState; + yytos->major = yyMajor; + yytos->minor = *yypMinor; +#ifndef NDEBUG + if( yyTraceFILE && yypParser->yyidx>0 ){ + int i; + fprintf(yyTraceFILE,"%sShift %d\n",yyTracePrompt,yyNewState); + fprintf(yyTraceFILE,"%sStack:",yyTracePrompt); + for(i=1; i<=yypParser->yyidx; i++) + fprintf(yyTraceFILE," %s",yyTokenName[yypParser->yystack[i].major]); + fprintf(yyTraceFILE,"\n"); + } +#endif +} + +/* The following table contains information about every rule that +** is used during the reduce. +*/ +static const 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(yyParser*); /* 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 */ +){ + int yygoto; /* The next state */ + int yyact; /* The next action */ + YYMINORTYPE yygotominor; /* The LHS of the rule reduced */ + yyStackEntry *yymsp; /* The top of the parser's stack */ + int yysize; /* Amount to pop the stack */ + ParseARG_FETCH; + yymsp = &yypParser->yystack[yypParser->yyidx]; +#ifndef NDEBUG + if( yyTraceFILE && yyruleno>=0 + && yyruleno<(int)(sizeof(yyRuleName)/sizeof(yyRuleName[0])) ){ + fprintf(yyTraceFILE, "%sReduce [%s].\n", yyTracePrompt, + yyRuleName[yyruleno]); + } +#endif /* NDEBUG */ + +#ifndef NDEBUG + /* Silence complaints from purify about yygotominor being uninitialized + ** in some cases when it is copied into the stack after the following + ** switch. yygotominor is uninitialized when a rule reduces that does + ** not set the value of its left-hand side nonterminal. Leaving the + ** value of the nonterminal uninitialized is utterly harmless as long + ** as the value is never used. So really the only thing this code + ** accomplishes is to quieten purify. + */ + memset(&yygotominor, 0, sizeof(yygotominor)); +#endif + + switch( yyruleno ){ + /* Beginning here are the reduction cases. A typical example + ** follows: + ** case 0: + ** #line + ** { ... } // User supplied code + ** #line + ** break; + */ +%% + }; + yygoto = yyRuleInfo[yyruleno].lhs; + yysize = yyRuleInfo[yyruleno].nrhs; + yypParser->yyidx -= yysize; + yyact = yy_find_reduce_action(yymsp[-yysize].stateno,yygoto); + if( yyact < YYNSTATE ){ +#ifdef NDEBUG + /* If we are not debugging and the reduce action popped at least + ** one element off the stack, then we can push the new element back + ** onto the stack here, and skip the stack overflow test in yy_shift(). + ** That gives a significant speed improvement. */ + if( yysize ){ + yypParser->yyidx++; + yymsp -= yysize-1; + yymsp->stateno = yyact; + yymsp->major = yygoto; + yymsp->minor = yygotominor; + }else +#endif + { + yy_shift(yypParser,yyact,yygoto,&yygotominor); + } + }else if( yyact == YYNSTATE + YYNRULE + 1 ){ + yy_accept(yypParser); + } +} + +/* +** The following code executes when the parse fails +*/ +static void yy_parse_failed( + yyParser *yypParser /* The parser */ +){ + ParseARG_FETCH; +#ifndef NDEBUG + if( yyTraceFILE ){ + fprintf(yyTraceFILE,"%sFail!\n",yyTracePrompt); + } +#endif + while( yypParser->yyidx>=0 ) yy_pop_parser_stack(yypParser); + /* Here code is inserted which will be executed whenever the + ** parser fails */ +%% + ParseARG_STORE; /* Suppress warning about unused %extra_argument variable */ +} + +/* +** 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 */ +){ + ParseARG_FETCH; +#define TOKEN (yyminor.yy0) +%% + ParseARG_STORE; /* Suppress warning about unused %extra_argument variable */ +} + +/* +** The following is executed when the parser accepts +*/ +static void yy_accept( + yyParser *yypParser /* The parser */ +){ + ParseARG_FETCH; +#ifndef NDEBUG + if( yyTraceFILE ){ + fprintf(yyTraceFILE,"%sAccept!\n",yyTracePrompt); + } +#endif + while( yypParser->yyidx>=0 ) yy_pop_parser_stack(yypParser); + /* Here code is inserted which will be executed whenever the + ** parser accepts */ +%% + ParseARG_STORE; /* Suppress warning about unused %extra_argument variable */ +} + +/* 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. +*/ +void Parse( + void *yyp, /* The parser */ + int yymajor, /* The major token code number */ + ParseTOKENTYPE yyminor /* The value for the token */ + ParseARG_PDECL /* Optional %extra_argument parameter */ +){ + 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->yyidx<0 ){ + /* if( yymajor==0 ) return; // not sure why this was here... */ + yypParser->yyidx = 0; + yypParser->yyerrcnt = -1; + yypParser->yystack[0].stateno = 0; + yypParser->yystack[0].major = 0; + } + yyminorunion.yy0 = yyminor; + yyendofinput = (yymajor==0); + ParseARG_STORE; + +#ifndef NDEBUG + if( yyTraceFILE ){ + fprintf(yyTraceFILE,"%sInput %s\n",yyTracePrompt,yyTokenName[yymajor]); + } +#endif + + do{ + yyact = yy_find_shift_action(yypParser,yymajor); + if( yyactyyerrcnt--; + if( yyendofinput && yypParser->yyidx>=0 ){ + yymajor = 0; + }else{ + yymajor = YYNOCODE; + } + }else if( yyact < YYNSTATE + YYNRULE ){ + yy_reduce(yypParser,yyact-YYNSTATE); + }else if( yyact == YY_ERROR_ACTION ){ + int yymx; +#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->yyerrcnt<0 ){ + yy_syntax_error(yypParser,yymajor,yyminorunion); + } + yymx = yypParser->yystack[yypParser->yyidx].major; + if( yymx==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->yyidx >= 0 && + yymx != YYERRORSYMBOL && + (yyact = yy_find_reduce_action( + yypParser->yystack[yypParser->yyidx].stateno, + YYERRORSYMBOL)) >= YYNSTATE + ){ + yy_pop_parser_stack(yypParser); + } + if( yypParser->yyidx < 0 || yymajor==0 ){ + yy_destructor(yymajor,&yyminorunion); + yy_parse_failed(yypParser); + yymajor = YYNOCODE; + }else if( yymx!=YYERRORSYMBOL ){ + YYMINORTYPE u2; + u2.YYERRSYMDT = 0; + yy_shift(yypParser,yyact,YYERRORSYMBOL,&u2); + } + } + yypParser->yyerrcnt = 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->yyerrcnt<=0 ){ + yy_syntax_error(yypParser,yymajor,yyminorunion); + } + yypParser->yyerrcnt = 3; + yy_destructor(yymajor,&yyminorunion); + if( yyendofinput ){ + yy_parse_failed(yypParser); + } + yymajor = YYNOCODE; +#endif + }else{ + yy_accept(yypParser); + yymajor = YYNOCODE; + } + }while( yymajor!=YYNOCODE && yypParser->yyidx>=0 ); + return; +}