qzdoom/tools/lemon/lempar.c

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/* 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 <stdio.h>
#ifndef NDEBUG
#include <string.h>
#endif
%%
/* 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 (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 <stdio.h>
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:
** <ul>
** <li> A FILE* to which trace output should be written.
** If NULL, then tracing is turned off.
** <li> A prefix string written at the beginning of every
** line of trace output. If NULL, then tracing is
** turned off.
** </ul>
**
** 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<(sizeof(yyTokenName)/sizeof(yyTokenName[0])) ){
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:
** <ul>
** <li> A pointer to the parser. This should be a pointer
** obtained from ParseAlloc.
** <li> A pointer to a function used to reclaim memory obtained
** from malloc.
** </ul>
*/
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 */
int 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 ){
#ifdef YYFALLBACK
int iFallback; /* Fallback token */
if( iLookAhead<sizeof(yyFallback)/sizeof(yyFallback[0])
&& (iFallback = yyFallback[iLookAhead])!=0 ){
#ifndef NDEBUG
if( yyTraceFILE ){
fprintf(yyTraceFILE, "%sFALLBACK %s => %s\n",
yyTracePrompt, yyTokenName[iLookAhead], yyTokenName[iFallback]);
}
#endif
return yy_find_shift_action(pParser, iFallback);
}
#endif
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 */
int 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<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 <lineno> <grammarfile>
** { ... } // User supplied code
** #line <lineno> <thisfile>
** 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:
** <ul>
** <li> A pointer to the parser (an opaque structure.)
** <li> The major token number.
** <li> The minor token number.
** <li> An option argument of a grammar-specified type.
** </ul>
**
** 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( yyact<YYNSTATE ){
yy_shift(yypParser,yyact,yymajor,&yyminorunion);
yypParser->yyerrcnt--;
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;
}