gen.c

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		if ( (e=g=set_pdq(fset[k])) == NULL ) fatal_internal("genExpr: cannot allocate IF expr pdq set");
		for (; *e!=nil; e++)
		{
			if ( !firstTime ) _gen(" || ") else { _gen("("); firstTime = 0; }
			on1line++;
			if ( on1line > NumExprPerLine ) { on1line=0; _gen("\n"); }
			_gen1("LA(%d)==",k);
			if ( TokenString(*e) == NULL ) _gen1("%d", *e)
			else _gen1("%s", TokenString(*e));
		}
		free( (char *)g );
		_gen(")");
		if ( k>max_k ) max_k = k;
		if ( k == CLL_k ) break;
		k++;
		if ( k <= limit && !set_nil(fset[k]) ) { firstTime=1; _gen(" && "); }   /* MR11 */
		on1line++;
		if ( on1line > NumExprPerLine ) { on1line=0; _gen("\n"); }
	}
	return max_k;
}

/*
 * Generate code for any type of block.  If the last alternative in the block is
 * empty (not even an action) don't bother doing it.  This permits us to handle
 * optional and loop blocks as well.
 *
 * Only do this block, return after completing the block.
 * This routine is visible only to this file and cannot answer a TRANS message.
 */
static set
#ifdef __USE_PROTOS
genBlk( Junction *q, int jtype, int *max_k, int *need_right_curly )
#else
genBlk( q, jtype, max_k, need_right_curly )
Junction *q;
int jtype;
int *max_k;
int *need_right_curly;
#endif
{
	set f;
	Junction *alt;
	int a_guess_in_block = 0;
	require(q!=NULL,				"genBlk: invalid node");
	require(q->ntype == nJunction,	"genBlk: not junction");

	*need_right_curly=0;
	if ( q->p2 == NULL )	/* only one alternative?  Then don't need if */
	{	
		if (first_item_is_guess_block((Junction *)q->p1)!=NULL )
		{
            if (jtype != aLoopBlk && jtype != aOptBlk && jtype != aPlusBlk) {
  			  warnFL("(...)? as only alternative of block is unnecessary", FileStr[q->file], q->line);
            };
   	   	    gen("zzGUESS\n");	/* guess anyway to make output code consistent */
/* MR10 disable */  /**** gen("if ( !zzrv )\n"); ****/
/* MR10 */          gen("if ( !zzrv ) {\n"); tabs++; (*need_right_curly)++;
        };
		TRANS(q->p1);
		return empty;		/* no decision to be made-->no error set */
	}

	f = First(q, 1, jtype, max_k);
	for (alt=q; alt != NULL; alt= (Junction *) alt->p2 )
	{
		if ( alt->p2 == NULL )					/* chk for empty alt */
		{	
			Node *p = alt->p1;
			if ( p->ntype == nJunction )
			{
				/* we have empty alt */
				if ( ((Junction *)p)->p1 == (Node *)q->end )
				{
					break;						/* don't do this one, quit */
				}
			}
		}
/* MR10 */        if (alt->p2 == NULL &&
/* MR10 */               ( q->jtype == aSubBlk || q->jtype == RuleBlk) ) {
/* MR10 */          if (first_item_is_guess_block(alt)) {
/* MR10 */               warnFL("(...)? as last alternative of block is unnecessary",
/* MR10 */                                FileStr[alt->file],alt->line);
/* MR10 */          };
/* MR10 */        };

		if ( alt != q ) gen("else ")
		else
		{
			if ( DemandLookahead )
				if ( !GenCC ) {gen1("LOOK(%d);\n", *max_k);}
				else gen1("look(%d);\n", *max_k);
		}

		if ( alt!=q )
		{
			_gen("{\n");
			tabs++;
			(*need_right_curly)++;
			/* code to restore state if a prev alt didn't follow guess */
			if ( a_guess_in_block )
				gen("if ( !zzrv ) zzGUESS_DONE;\n");
		}
		if ( first_item_is_guess_block((Junction *)alt->p1)!=NULL )
		{
			a_guess_in_block = 1;
			gen("zzGUESS\n");
		}
		gen("if ( ");
		if ( first_item_is_guess_block((Junction *)alt->p1)!=NULL ) _gen("!zzrv && ");
		genExpr(alt);
		_gen(" ) ");
		_gen("{\n");
		tabs++;
		TRANS(alt->p1);
		--tabs;
		gen("}\n");
/* MR10 */        if (alt->p2 == NULL) {
/* MR10 */          if (first_item_is_guess_block(alt)) {
/* MR10 */            gen("/* MR10 */ else {\n");
/* MR10 */            tabs++;
/* MR10 */  		  (*need_right_curly)++;
/* MR10 */  		  /* code to restore state if a prev alt didn't follow guess */
/* MR10 */            gen("/* MR10 */ if ( !zzrv ) zzGUESS_DONE;\n");
/* MR10 */            gen("/* MR10 */ if (0) {}     /* last alternative of block is guess block */\n");
/* MR10 */          };
/* MR10 */        };
	}
	return f;
}

static int
#ifdef __USE_PROTOS
has_guess_block_as_first_item( Junction *q )
#else
has_guess_block_as_first_item( q )
Junction *q;
#endif
{
	Junction *alt;

	for (alt=q; alt != NULL; alt= (Junction *) alt->p2 )
	{
		if ( first_item_is_guess_block((Junction *)alt->p1)!=NULL ) return 1;
	}
	return 0;
}

static int
#ifdef __USE_PROTOS
has_guess_block_as_last_item( Junction *q )
#else
has_guess_block_as_last_item( q )
Junction *q;
#endif
{
	Junction *alt;

    if (q == NULL) return 0;
	for (alt=q; alt->p2 != NULL && !( (Junction *) alt->p2)->ignore; alt= (Junction *) alt->p2 ) {};
    return first_item_is_guess_block( (Junction *) alt->p1) != NULL;
}

/* return NULL if 1st item of alt is NOT (...)? block; else return ptr to aSubBlk node
 * of (...)?;  This function ignores actions and predicates.
 */
Junction *
#ifdef __USE_PROTOS
first_item_is_guess_block( Junction *q )
#else
first_item_is_guess_block( q )
Junction *q;
#endif
{
    /* MR14  Couldnt' find aSubBlock which was a guess block when it lay
             behind aLoopBlk.  The aLoopBlk only appear in conjunction with
             aLoopBegin, but the routine didn't know that.  I think.
    */

	while ( q!=NULL &&
          ( q->ntype==nAction ) ||
          ( q->ntype==nJunction && (q->jtype==Generic || q->jtype == aLoopBlk )) )
	{
		if ( q->ntype==nJunction ) q = (Junction *)q->p1;
		else q = (Junction *) ((ActionNode *)q)->next;
	}

	if ( q==NULL ) return NULL;
	if ( q->ntype!=nJunction ) return NULL;
	if ( q->jtype!=aSubBlk ) return NULL;
	if ( !q->guess ) return NULL;
	return q;
}

/* MR1				                 					    */
/* MR1  10-Apr-97 MR1 Routine to stringize failed semantic predicates msgs  */
/* MR1				                                                        */

#define STRINGIZEBUFSIZE 1024

static char stringizeBuf[STRINGIZEBUFSIZE];
char *
#ifdef __USE_PROTOS
stringize(char * s)
#else
stringize(s)
char *s;
#endif

{
  char		*p;
  char		*stop;

  p=stringizeBuf;
  stop=&stringizeBuf[1015];

  if (s != 0) {
    while (*s != 0) {
      if (p >= stop) {
	goto stringizeStop;
      } else if (*s == '\n') {
        *p++='\\';
        *p++='n';
        *p++='\\';
	*p++=*s++;
      } else if (*s == '\\') {
	*p++=*s;
	*p++=*s++;
      } else if (*s == '\"') {
        *p++='\\';
	*p++=*s++;
        while (*s != 0) {
          if (p >= stop) {
	     goto stringizeStop;
	  } else if (*s == '\n') {
	    *p++='\\';
	    *p++=*s++;
	  } else if (*s == '\\') {
	    *p++=*s++;
	    *p++=*s++;
	  } else if (*s == '\"') {
	    *p++='\\';
	    *p++=*s++;
	    break;
	  } else {
	    *p++=*s++;
          };
        };
      } else if (*s == '\'') {
	*p++=*s++;
        while (*s != 0) {
          if (p >= stop) {
	     goto stringizeStop;
	  } else if (*s == '\'') {
	    *p++=*s++;
	    break;
	  } else if (*s == '\\') {
	    *p++=*s++;
	    *p++=*s++;
	  } else if (*s == '\"') {
	    *p++='\\';
	    *p++=*s++;
	    break;
	  } else {
	    *p++=*s++;
          };
        };
      } else {
        *p++=*s++;
      };
    };
  };
  goto stringizeExit;
stringizeStop:
  *p++='.';        	
  *p++='.';        	
  *p++='.';        	
stringizeExit:
  *p=0;
  return stringizeBuf;
}

#ifdef __STDC__
int isNullAction(char *s)
#else
int isNullAction(s)
  char  *s;
#endif
{
  char  *p;
  for (p=s; *p != '\0' ; p++) {
    if (*p != ';' && *p !=' ') return 0;
  };
  return 1;
}
/* MR1									                                    */
/* MR1	End of Routine to stringize code for failed predicates msgs         */
/* MR1				                                                        */

/* Generate an action.  Don't if action is NULL which means that it was already
 * handled as an init action.
 */
void
#ifdef __USE_PROTOS
genAction( ActionNode *p )
#else
genAction( p )
ActionNode *p;
#endif
{
	require(p!=NULL,			"genAction: invalid node and/or rule");
	require(p->ntype==nAction,	"genAction: not action");
	
	if ( !p->done )  /* MR10 */ /* MR11 */
	{
		if ( p->is_predicate)
		{
			if ( p->guardpred != NULL )
			{
                Predicate *guardDup=predicate_dup(p->guardpred); /* MR10 */
                gen("if (!");
       			guardDup=genPredTreeMain(guardDup, (Node *)p);
                predicate_free(guardDup);
			}
/* MR10 */  else if (p->ampersandPred != NULL) {
/* MR10 */      gen("if (!");
/* MR10 */      p->ampersandPred=genPredTreeMain(p->ampersandPred, (Node *)p);
/* MR10 */  }
			else
			{
				gen("if (!(");
				/* make sure that '#line n' is on front of line */
				if ( GenLineInfo && p->file != -1 ) _gen("\n");
				dumpPredAction(p,p->action, output, 0, p->file, p->line, 0);
				_gen(")");
			}
			if ( p->pred_fail != NULL )
			{
				_gen(")\n");
				tabs++;
/* MR1				                                                        */
/* MR1  10-Apr-97 MR1  Put {...} envelope around failed semantic predicates */
/* MR1				                                                        */
				gen1("{%s};\n", p->pred_fail);	                     /* MR1 */
				tabs--;
			}
/* MR1						                                                */
/* MR1  10-Apr-97 MR1	Properly stringize failed semantic predicates 	    */
/* MR1				                                                        */
			else _gen1(") {zzfailed_pred(\"%s\");}\n",               /* MR1 */
					stringize(p->action));	                     /* MR1 */
		}
		else    /* not a predicate */
		{
            if (! isNullAction(p->action) && !p->noHoist) {
  	  		  if ( FoundGuessBlk ) {
				if ( GenCC ) {
                  gen("if ( !guessing ) {\n");
                } else {
				  gen("zzNON_GUESS_MODE {\n");
                };
              };
			  dumpAction(p->action, output, tabs, p->file, p->line, 1);
			  if ( FoundGuessBlk ) gen("}\n");
            };
		}
	}
	TRANS(p->next)
}

/*
 *		if invoking rule has !noAST pass zzSTR to rule ref and zzlink it in
 *		else pass addr of temp root ptr (&_ast) (don't zzlink it in).
 *
 *		if ! modifies rule-ref, then never link it in and never pass zzSTR.
 *		Always pass address of temp root ptr.
 */
void
#ifdef __USE_PROTOS
genRuleRef( RuleRefNode *p )
#else
genRuleRef( p )
RuleRefNode *p;
#endif
{
	Junction *q;
	char *handler_id = "";
	RuleEntry *r, *r2;
	char *parm = "", *exsig = "";

    int     genRuleRef_emittedGuessGuard=0;     /* MR10 */

	require(p!=NULL,			"genRuleRef: invalid node and/or rule");
	require(p->ntype==nRuleRef, "genRuleRef: not rule reference");
	
	if ( p->altstart!=NULL && p->altstart->exception_label!=NULL )
		handler_id = p->altstart->exception_label;

	r = (RuleEntry *) hash_get(Rname, p->text);
	if ( r == NULL )
	{
		warnFL( eMsg1("rule %s not defined",
					  p->text), FileStr[p->file], p->line );
		return;
	}

/* MR8 5-Aug-97     Reported by [e-mail]                  */
/*                  Don't do assign when no return values declared          */
/*                  Move definition of q up and use it to guard p->assign   */

	q = RulePtr[r->rulenum];	/* find definition of ref'd rule */  /* MR8 */

	r2 = (RuleEntry *) hash_get(Rname, p->rname);
	if ( r2 == NULL ) {warnNoFL("Rule hash table is screwed up beyond belief"); return;}

    OutLineInfo(output,p->line,FileStr[p->file]);

	if ( GenCC && GenAST ) {
		gen("_ast = NULL;\n");
	}

	if ( FoundGuessBlk && p->assign!=NULL && q->ret != NULL ) {      /* MR8 */
		if ( GenCC ) {
          gen("if ( !guessing ) {\n");
        } else {
          gen("zzNON_GUESS_MODE {\n");
        };
        tabs++;                                                      /* MR11 */
        genRuleRef_emittedGuessGuard=1;                              /* MR11 */
    };

	if ( FoundException ) exsig = "&_signal";

	tab();
	if ( GenAST )
	{
		if ( GenCC ) {
/****			if ( r2->noAST || p->astnode==ASTexclude )
****/
			{
/****				_gen("_ast = NULL;\n");
****/
				parm = "&_ast";
			}
/*** we always want to set just a pointer now, then set correct
pointer after

			else {
				_gen("_astp =
(_tail==NULL)?(&_sibling):(&(_tail->_right));\n");
				parm = "_astp";
			}
****/
		}
		else {
			if ( r2->noAST || p->astnode==ASTexclude )
			{
				_gen("_ast = NULL; ");
				parm = "&_ast";
			}
			else parm = "zzSTR";
		}
		if ( p->assign!=NULL && q->ret!=NULL )                       /* MR8 */
		{
			if ( !HasComma(p->assign) ) {_gen1("%s = ",p->assign);}
			else _gen1("{ struct _rv%d _trv; _trv = ", r->rulenum);
		}
		if ( FoundException ) {
			_gen5("%s%s(%s,&_signal%s%s); ",
				  RulePrefix,
				  p->text,
				  parm,
				  (p->parms!=NULL)?",":"",
				  (p->parms!=NULL)?p->parms:"");
			if ( p->ex_group!=NULL ) {
				_gen("\n");
				gen("if (_signal) {\n");
				tabs++;
				dumpException(p->ex_group, 0);
				tabs--;
				gen("}");
			}
			else {
				_gen1("if (_signal) goto %s_handler;", handler_id);
			}
		}
		else {
			_gen5("%s%s(%s%s%s);",
				  RulePrefix,
				  p->text,
				  parm,
				  (p->parms!=NULL)?",":"",
				  (p->parms!=NULL)?p->parms:"");
		}
		if ( GenCC && (r2->noAST || p->astnode==ASTexclude) )
		{
			/* rule has a ! or element does */
			/* still need to assign to #i so we can play with it */
			_gen("\n");
			gen2("_ast%d%d = (AST *)_ast;", BlkLevel-1, p->elnum);
		}