#sccs "@(#)yacc:yaccpar 1.1" /* ** Skeleton parser driver for yacc output */ /* ** yacc user known macros and defines */ #define YYERROR goto yyerrlab #define YYACCEPT return(0) #define YYABORT return(1) #define YYBACKUP( newtoken, newvalue )\ {\ if ( yychar >= 0 || ( yyr2[ yytmp ] >> 1 ) != 1 )\ {\ yyerror( "syntax error - cannot backup" );\ goto yyerrlab;\ }\ yychar = newtoken;\ yystate = *yyps;\ yylval = newvalue;\ goto yynewstate;\ } #define YYRECOVERING() (!!yyerrflag) #ifndef YYDEBUG # define YYDEBUG 1 /* make debugging available */ #endif /* ** user known globals */ int yydebug; /* set to 1 to get debugging */ /* ** driver internal defines */ #define YYFLAG (-1000) /* ** global variables used by the parser */ YYSTYPE yyv[ YYMAXDEPTH ]; /* value stack */ int yys[ YYMAXDEPTH ]; /* state stack */ YYSTYPE *yypv; /* top of value stack */ int *yyps; /* top of state stack */ int yystate; /* current state */ int yytmp; /* extra var (lasts between blocks) */ int yynerrs; /* number of errors */ int yyerrflag; /* error recovery flag */ int yychar; /* current input token number */ /* ** yyparse - return 0 if worked, 1 if syntax error not recovered from */ int yyparse() { register YYSTYPE *yypvt; /* top of value stack for $vars */ /* ** Initialize externals - yyparse may be called more than once */ yypv = &yyv[-1]; yyps = &yys[-1]; yystate = 0; yytmp = 0; yynerrs = 0; yyerrflag = 0; yychar = -1; goto yystack; { register YYSTYPE *yy_pv; /* top of value stack */ register int *yy_ps; /* top of state stack */ register int yy_state; /* current state */ register int yy_n; /* internal state number info */ /* ** get globals into registers. ** branch to here only if YYBACKUP was called. */ yynewstate: yy_pv = yypv; yy_ps = yyps; yy_state = yystate; goto yy_newstate; /* ** get globals into registers. ** either we just started, or we just finished a reduction */ yystack: yy_pv = yypv; yy_ps = yyps; yy_state = yystate; /* ** top of for (;;) loop while no reductions done */ yy_stack: /* ** put a state and value onto the stacks */ #if YYDEBUG /* ** if debugging, look up token value in list of value vs. ** name pairs. 0 and negative (-1) are special values. ** Note: linear search is used since time is not a real ** consideration while debugging. */ if ( yydebug ) { register int yy_i; printf( "State %d, token ", yy_state ); if ( yychar == 0 ) printf( "end-of-file\n" ); else if ( yychar < 0 ) printf( "-none-\n" ); else { for ( yy_i = 0; yytoks[yy_i].t_val >= 0; yy_i++ ) { if ( yytoks[yy_i].t_val == yychar ) break; } printf( "%s\n", yytoks[yy_i].t_name ); } } #endif /* YYDEBUG */ if ( ++yy_ps >= &yys[ YYMAXDEPTH ] ) /* room on stack? */ { yyerror( "yacc stack overflow" ); YYABORT; } *yy_ps = yy_state; *++yy_pv = yyval; /* ** we have a new state - find out what to do */ yy_newstate: if ( ( yy_n = yypact[ yy_state ] ) <= YYFLAG ) goto yydefault; /* simple state */ #if YYDEBUG /* ** if debugging, need to mark whether new token grabbed */ yytmp = yychar < 0; #endif if ( ( yychar < 0 ) && ( ( yychar = yylex() ) < 0 ) ) yychar = 0; /* reached EOF */ #if YYDEBUG if ( yydebug && yytmp ) { register int yy_i; printf( "Received token " ); if ( yychar == 0 ) printf( "end-of-file\n" ); else if ( yychar < 0 ) printf( "-none-\n" ); else { for ( yy_i = 0; yytoks[yy_i].t_val >= 0; yy_i++ ) { if ( yytoks[yy_i].t_val == yychar ) break; } printf( "%s\n", yytoks[yy_i].t_name ); } } #endif /* YYDEBUG */ if ( ( ( yy_n += yychar ) < 0 ) || ( yy_n >= YYLAST ) ) goto yydefault; if ( yychk[ yy_n = yyact[ yy_n ] ] == yychar ) /*valid shift*/ { yychar = -1; yyval = yylval; yy_state = yy_n; if ( yyerrflag > 0 ) yyerrflag--; goto yy_stack; } yydefault: if ( ( yy_n = yydef[ yy_state ] ) == -2 ) { #if YYDEBUG yytmp = yychar < 0; #endif if ( ( yychar < 0 ) && ( ( yychar = yylex() ) < 0 ) ) yychar = 0; /* reached EOF */ #if YYDEBUG if ( yydebug && yytmp ) { register int yy_i; printf( "Received token " ); if ( yychar == 0 ) printf( "end-of-file\n" ); else if ( yychar < 0 ) printf( "-none-\n" ); else { for ( yy_i = 0; yytoks[yy_i].t_val >= 0; yy_i++ ) { if ( yytoks[yy_i].t_val == yychar ) { break; } } printf( "%s\n", yytoks[yy_i].t_name ); } } #endif /* YYDEBUG */ /* ** look through exception table */ { register int *yyxi = yyexca; while ( ( *yyxi != -1 ) || ( yyxi[1] != yy_state ) ) { yyxi += 2; } while ( ( *(yyxi += 2) >= 0 ) && ( *yyxi != yychar ) ) ; if ( ( yy_n = yyxi[1] ) < 0 ) YYACCEPT; } } /* ** check for syntax error */ if ( yy_n == 0 ) /* have an error */ { /* no worry about speed here! */ switch ( yyerrflag ) { case 0: /* new error */ yyerror( "syntax error" ); goto skip_init; yyerrlab: /* ** get globals into registers. ** we have a user generated syntax type error */ yy_pv = yypv; yy_ps = yyps; yy_state = yystate; yynerrs++; skip_init: case 1: case 2: /* incompletely recovered error */ /* try again... */ yyerrflag = 3; /* ** find state where "error" is a legal ** shift action */ while ( yy_ps >= yys ) { yy_n = yypact[ *yy_ps ] + YYERRCODE; if ( yy_n >= 0 && yy_n < YYLAST && yychk[yyact[yy_n]] == YYERRCODE) { /* ** simulate shift of "error" */ yy_state = yyact[ yy_n ]; goto yy_stack; } /* ** current state has no shift on ** "error", pop stack */ #if YYDEBUG # define _POP_ "Error recovery pops state %d, uncovers state %d\n" if ( yydebug ) printf( _POP_, *yy_ps, yy_ps[-1] ); # undef _POP_ #endif yy_ps--; yy_pv--; } /* ** there is no state on stack with "error" as ** a valid shift. give up. */ YYABORT; case 3: /* no shift yet; eat a token */ #if YYDEBUG /* ** if debugging, look up token in list of ** pairs. 0 and negative shouldn't occur, ** but since timing doesn't matter when ** debugging, it doesn't hurt to leave the ** tests here. */ if ( yydebug ) { register int yy_i; printf( "Error recovery discards " ); if ( yychar == 0 ) printf( "token end-of-file\n" ); else if ( yychar < 0 ) printf( "token -none-\n" ); else { for ( yy_i = 0; yytoks[yy_i].t_val >= 0; yy_i++ ) { if ( yytoks[yy_i].t_val == yychar ) { break; } } printf( "token %s\n", yytoks[yy_i].t_name ); } } #endif /* YYDEBUG */ if ( yychar == 0 ) /* reached EOF. quit */ YYABORT; yychar = -1; goto yy_newstate; } }/* end if ( yy_n == 0 ) */ /* ** reduction by production yy_n ** put stack tops, etc. so things right after switch */ #if YYDEBUG /* ** if debugging, print the string that is the user's ** specification of the reduction which is just about ** to be done. */ if ( yydebug ) printf( "Reduce by (%d) \"%s\"\n", yy_n, yyreds[ yy_n ] ); #endif yytmp = yy_n; /* value to switch over */ yypvt = yy_pv; /* $vars top of value stack */ /* ** Look in goto table for next state ** Sorry about using yy_state here as temporary ** register variable, but why not, if it works... ** If yyr2[ yy_n ] doesn't have the low order bit ** set, then there is no action to be done for ** this reduction. So, no saving & unsaving of ** registers done. The only difference between the ** code just after the if and the body of the if is ** the goto yy_stack in the body. This way the test ** can be made before the choice of what to do is needed. */ { /* length of production doubled with extra bit */ register int yy_len = yyr2[ yy_n ]; if ( !( yy_len & 01 ) ) { yy_len >>= 1; yyval = ( yy_pv -= yy_len )[1]; /* $$ = $1 */ yy_state = yypgo[ yy_n = yyr1[ yy_n ] ] + *( yy_ps -= yy_len ) + 1; if ( yy_state >= YYLAST || yychk[ yy_state = yyact[ yy_state ] ] != -yy_n ) { yy_state = yyact[ yypgo[ yy_n ] ]; } goto yy_stack; } yy_len >>= 1; yyval = ( yy_pv -= yy_len )[1]; /* $$ = $1 */ yy_state = yypgo[ yy_n = yyr1[ yy_n ] ] + *( yy_ps -= yy_len ) + 1; if ( yy_state >= YYLAST || yychk[ yy_state = yyact[ yy_state ] ] != -yy_n ) { yy_state = yyact[ yypgo[ yy_n ] ]; } } /* save until reenter driver code */ yystate = yy_state; yyps = yy_ps; yypv = yy_pv; } /* ** code supplied by user is placed in this switch */ switch( yytmp ) { $A } goto yystack; /* reset registers in driver code */ }