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ey2.c
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C/C++ Source or Header
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1980-02-17
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12KB
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536 lines
/* (c) 1979 Regents of the University of California */
# include "ey.h"
# define IDENTIFIER 257
# define MARK 258
# define TERM 259
# define LEFT 260
# define BINARY 261
# define RIGHT 262
# define PREC 263
# define LCURLY 264
# define C_IDENTIFIER 265 /* name followed by colon */
# define NUMBER 266
setup(argc,argv) int argc; char *argv[];
{ int i,j,lev,t;
int c;
foutput = -2;
i = 1;
while( argc >= 2 && argv[1][0] == '-' ) {
while( *++(argv[1]) ){
switch( *argv[1] ){
case 'v':
case 'V':
foutput = copen("y.output", 'w' );
if( foutput < 0 ) error( "cannot open y.output");
continue;
case 'o':
case 'O':
oflag = 1;
continue;
case 'r':
case 'R':
oflag = 1;
rflag = 1;
continue;
default: error( "illegal option: %c", *argv[1]);
}
}
argv++;
argc--;
}
ftable = copen( oflag ? "yacc.tmp" : "y.tab.c" , 'w' );
if( ftable<0 ) error( "cannot open table file" );
if( argc > 1 ) cin = copen( argv[1], 'r' );
if( cin < 0 ) error( "cannot open input" );
settab();
printf("#\n");
ctokn = "$end";
defin(0); /* eof */
extval = 0400; /* beginning of assigned values */
ctokn = "error";
defin(0);
ctokn = "$accept";
defin(1);
mem=mem0;
cnamp = cnames;
lev=0;
i=0;
while( t = gettok() ){
switch( t ){
case IDENTIFIER: j = chfind(0);
trmlev[j] = lev;
continue;
case ',':
case ';': continue;
case TERM: lev=0; continue;
case LEFT: lev=(++i<<3)|01; continue;
case BINARY: lev=(++i<<3)|02; continue;
case RIGHT: lev=(++i<<3)|03; continue;
case MARK:
defout();
if( rflag ){ /* RATFOR */
printf( "define yyerrok yyerrf = 0\n" );
printf( "define yyclearin yychar = -1\n" );
printf( "subroutine yyactr(yyprdn)\n");
printf( "common/yycomn/yylval,yyval,yypv,yyvalv(150)\n" );
printf( "common/yylcom/yychar,yyerrf,yydebu\n" );
printf( "integer yychar, yyerrf, yydebu\n" );
printf( "integer yyprdn,yyval,yylval,yypv,yyvalv\n" );
}
else {
printf( "#define yyclearin yychar = -1\n" );
printf( "#define yyerrok yyerrflag = 0\n" );
printf( "extern int yychar, yyerrflag;\n" );
printf("\nint yyval 0;\nint *yypv;\nint yylval 0;");
printf("\nyyactr(__np__){\n");
}
break;
case LCURLY: defout();
cpycode();
continue;
case NUMBER:
trmset[j].value = numbval;
if( j < ndefout && j>2 )
error("please define type # of %s earlier", trmset[j].name );
continue;
default: error("bad precedence syntax, input %d", t );
}
break;
}
prdptr[0]=mem;
/* added production */
*mem++ = NTBASE;
*mem++ = NTBASE+1;
*mem++ = 1;
*mem++ = 0;
prdptr[1]=mem;
i=0;
/* i is 0 when a rule can begin, 1 otherwise */
for(;;) switch( t=gettok() ) {
case C_IDENTIFIER: if( mem == prdptr[1] ) { /* first time */
if( rflag ){
printf( "goto 1000\n" );
}
else printf("\nswitch(__np__){\n");
}
if( i != 0 ) error( "previous rule not terminated" );
*mem = chfind(1);
if( *mem < NTBASE )error( "token illegal on lhs of grammar rule" );
i=1;
++mem;
continue;
case IDENTIFIER:
*mem=chfind(1);
if(*mem < NTBASE)levprd[nprod]=trmlev[*mem];
mem++;
if(i==0) error("missing :");
continue;
case '=': levprd[nprod] =| 04;
if( i==0 ) error("semicolon preceeds action");
printf( rflag?"\n%d ":"\ncase %d:", nprod );
cpyact();
printf( rflag ? " return" : " break;" );
case '|':
case ';': if(i){
*mem++ = -nprod;
prdptr[++nprod] = mem;
levprd[nprod]=0;
i=0;}
if (t=='|'){i=1;*mem++ = *prdptr[nprod-1];}
continue;
case 0: /* End Of File */
case MARK: if( i != 0 ) error( "rule not terminated before %%%% or EOF" );
settab();
finact();
/* copy the programs which follow the rules */
if( t == MARK ){
while (c=getchar()) putchar(c);
}
return;
case PREC:
if( i==0 ) error( "%%prec must appear inside rule" );
if( gettok()!=IDENTIFIER)error("illegal %%prec syntax" );
j=chfind(2);
if(j>=NTBASE)error("nonterminal %s illegal after %%prec", nontrst[j-NTBASE].name);
levprd[nprod]=trmlev[j];
continue;
case LCURLY:
if( i!=0 ) error( "%%{ appears within a rule" );
cpycode();
continue;
default: error( "syntax error, input %d", t );
}
}
finact(){
/* finish action routine */
register i;
if( rflag ){
printf( "\n1000 goto(" );
for( i=1; i<nprod; ++i ){
printf( "%d,", (levprd[i]&04)==0?999:i );
}
printf( "999),yyprdn\n" );
printf( "999 return\nend\n" );
printf( "define YYERRCODE %d\n", trmset[2].value );
}
else {
printf( "\n}\n}\n" );
printf( "int yyerrval %d;\n", trmset[2].value );
}
}
defin(t) {
/* define ctokn to be a terminal if t=0
or a nonterminal if t=1 */
char *cp,*p;
int c;
if (t) {
if( ++nnonter >= ntlim ) error("too many nonterminals, limit %d",ntlim);
nontrst[nnonter].name = ctokn;
return( NTBASE + nnonter );
}
else {
if( ++nterms >= tlim ) error("too many terminals, limit %d",tlim );
trmset[nterms].name = ctokn;
if( ctokn[0]==' ' && ctokn[2]=='\0' ) /* single character literal */
trmset[nterms].value = ctokn[1];
else if ( ctokn[0]==' ' && ctokn[1]=='\\' ) { /* escape sequence */
if( ctokn[3] == '\0' ){ /* single character escape sequence */
switch ( ctokn[2] ){
/* character which is escaped */
case 'n': trmset[nterms].value = '\n'; break;
case 'r': trmset[nterms].value = '\r'; break;
case 'b': trmset[nterms].value = '\b'; break;
case 't': trmset[nterms].value = '\t'; break;
case '\'': trmset[nterms].value = '\''; break;
case '"': trmset[nterms].value = '"'; break;
case '\\': trmset[nterms].value = '\\'; break;
default: error( "invalid escape" );
}
}
else if( ctokn[2] <= '7' && ctokn[2]>='0' ){ /* \nnn sequence */
if( ctokn[3]<'0' || ctokn[3] > '7' || ctokn[4]<'0' ||
ctokn[4]>'7' || ctokn[5] != '\0' ) error("illegal \\nnn construction" );
trmset[nterms].value = 64*(ctokn[2]-'0')+8*(ctokn[3]-'0')+ctokn[4]-'0';
if( trmset[nterms].value == 0 ) error( "'\\000' is illegal" );
}
}
else {
trmset[nterms].value = extval++;
}
trmlev[nterms] = 0;
return( nterms );
}
}
defout(){ /* write out the defines (at the end of the declaration section) */
_REGISTER int i, c;
_REGISTER char *cp;
for( i=ndefout; i<=nterms; ++i ){
cp = trmset[i].name;
if( *cp == ' ' ) ++cp; /* literals */
for( ; (c= *cp)!='\0'; ++cp ){
if( c>='a' && c<='z' ||
c>='A' && c<='Z' ||
c>='0' && c<='9' ||
c=='_' ) ; /* VOID */
else goto nodef;
}
/* define it */
printf( "%c define %s %d\n", rflag?' ':'#', trmset[i].name, trmset[i].value );
nodef: ;
}
ndefout = nterms+1;
}
chstash( c ){
/* put character away into cnames */
if( cnamp >= &cnames[cnamsz] ) error("too many characters in id's and literals" );
else *cnamp++ = c;
}
int gettok() {
int j, base;
static int peekline; /* number of '\n' seen in lookahead */
auto int c, match, reserve;
begin:
reserve = 0;
if( peekc>=0 ) {
c = peekc;
lineno =+ peekline;
peekc = -1;
peekline = 0;
}
else c = getchar();
while( c==' ' || c=='\n' || c=='\t' || c == '\014'){
if( c == '\n' ) ++lineno;
c=getchar();
}
if (c=='/')
{if (getchar()!='*')error("illegal /");
c=getchar();
while(c) {
if( c == '\n' ) ++lineno;
if (c=='*')
{if((c=getchar())=='/')break;}
else c=getchar();}
if (!c) return(0);
goto begin;}
j=0;
switch(c){
case '"':
case '\'': match = c;
ctokn = cnamp;
chstash( ' ' );
while(1){
c = getchar();
if( c == '\n' || c == '\0' )
error("illegal or missing ' or \"");
if( c == '\\' ){
c = getchar();
chstash( '\\' );
}
else if( c == match ) break;
chstash( c );
}
break;
case '%':
case '\\': switch(c=getchar())
{case '0': return(TERM);
case '<': return(LEFT);
case '2': return(BINARY);
case '>': return(RIGHT);
case '%':
case '\\': return(MARK);
case '=': return(PREC);
case '{': return(LCURLY);
default: reserve = 1;
}
default: if( c >= '0' && c <= '9' ){ /* number */
numbval = c-'0' ;
base = (c=='0') ? 8 : 10 ;
for( c=getchar(); c>='0' && c<='9'; c=getchar() ){
numbval = numbval*base + c - '0';
}
peekc = c;
return(NUMBER);
}
else if( (c>='a'&&c<='z')||(c>='A'&&c<='Z')||c=='_'||c=='.'||c=='$'){
ctokn = cnamp;
while( (c>='a'&&c<='z') ||
(c>='A'&&c<='Z') ||
(c>='0'&&c<='9') ||
c=='_' || c=='.' || c=='$' ) {
chstash( c );
if( peekc>=0 ) { c = peekc; peekc = -1; }
else c = getchar();
}
}
else return(c);
peekc=c;
}
chstash( '\0' );
if( reserve ){ /* find a reserved word */
if( compare("term")) return( TERM );
if( compare("TERM")) return( TERM );
if( compare("token")) return( TERM );
if( compare("TOKEN")) return( TERM );
if( compare("left")) return( LEFT );
if( compare("LEFT")) return( LEFT );
if( compare("nonassoc")) return( BINARY );
if( compare("NONASSOC")) return( BINARY );
if( compare("binary")) return( BINARY );
if( compare("BINARY")) return( BINARY );
if( compare("right")) return( RIGHT );
if( compare("RIGHT")) return( RIGHT );
if( compare("prec")) return( PREC );
if( compare("PREC")) return( PREC );
error("invalid escape, or illegal reserved word: %s", ctokn );
}
/* look ahead to distinguish IDENTIFIER from C_IDENTIFIER */
look:
while( peekc==' ' || peekc=='\t' || peekc == '\n' || peekc == '\014' )
{
if( peekc == '\n' ) ++peekline;
peekc = getchar();
}
if( peekc != ':' ) return( IDENTIFIER );
peekc = -1;
lineno =+ peekline;
peekline = 0;
return( C_IDENTIFIER );
}
chfind(t)
{ int i,j;
if (ctokn[0]==' ')t=0;
for(i=1;i<=nterms;i++)
if(compare(trmset[i].name)){
cnamp = ctokn;
return( i );
}
for(i=1;i<=nnonter;i++)
if(compare(nontrst[i].name)) {
cnamp = ctokn;
return( i+NTBASE );
}
/* cannot find name */
if( t>1 && ctokn[0] != ' ' )
error( "%s should have been defined earlier", ctokn );
return( defin( t ) );
}
cpycode(){ /* copies code between \{ and \} */
int c;
c = getchar();
if( c == '\n' ) {
c = getchar();
lineno++;
}
while( c ){
if( c=='\\' )
if( (c=getchar()) == '}' ) return;
else putchar('\\');
if( c=='%' )
if( (c=getchar()) == '}' ) return;
else putchar('%');
putchar( c );
if( c == '\n' ) ++lineno;
c = getchar();
}
error("eof before %%}");
}
cpyact(){ /* copy C action to the next ; or closing } */
int brac, c, match, *i, j, s;
brac = 0;
loop:
c = getchar();
swt:
switch( c ){
case ';':
if( brac == 0 ){
putchar( c );
return;
}
goto lcopy;
case '{':
brac++;
goto lcopy;
case '$':
s = 1;
c = getchar();
if( c == '$' ){
printf("yyval");
goto loop;
}
if( c == '-' ){
s = -s;
c = getchar();
}
if( c>='0' && c <= '9' ){
j=0;
while( c>='0' && c<= '9' ){
j= j*10+c-'0';
c = getchar();
}
if( rflag ) printf( "yyvalv(yypv%c%d)", s==1?'+':'-', j );
else printf("yypv[%d]", s*j );
goto swt;
}
putchar( '$' );
if( s<0 ) putchar('-');
goto swt;
case '}':
brac--;
if( brac == 0 ){
putchar( c );
return;
}
goto lcopy;
case '/': /* look for comments */
putchar( c );
c = getchar();
if( c != '*' ) goto swt;
/* it really is a comment */
putchar( c );
while( c=getchar() ){
if( c=='*' ){
putchar( c );
if( (c=getchar()) == '/' ) goto lcopy;
}
putchar( c );
}
error( "EOF inside comment" );
case '\'': /* character constant */
match = '\'';
goto string;
case '"': /* character string */
match = '"';
string:
putchar( c );
while( c=getchar() ){
if( c=='\\' ){
putchar( c );
c=getchar();
}
else if( c==match ) goto lcopy;
putchar( c );
}
error( "EOF in string or character constant" );
case '\0':
error("action does not terminate");
case '\n': ++lineno;
goto lcopy;
}
lcopy:
putchar( c );
goto loop;
}