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BSD 4_1c_2 release
[unix-history] / usr / src / usr.bin / yacc / y2.c
#ifndef lint
static char sccsid[] = "@(#)y2.c 4.1 (Berkeley) 2/11/83";
#endif not lint
# include "dextern"
# define IDENTIFIER 257
# define MARK 258
# define TERM 259
# define LEFT 260
# define RIGHT 261
# define BINARY 262
# define PREC 263
# define LCURLY 264
# define C_IDENTIFIER 265 /* name followed by colon */
# define NUMBER 266
# define START 267
# define TYPEDEF 268
# define TYPENAME 269
# define UNION 270
# define ENDFILE 0
/* communication variables between various I/O routines */
char *infile; /* input file name */
int numbval; /* value of an input number */
char tokname[NAMESIZE]; /* input token name */
/* storage of names */
char cnames[CNAMSZ]; /* place where token and nonterminal names are stored */
int cnamsz = CNAMSZ; /* size of cnames */
char * cnamp = cnames; /* place where next name is to be put in */
int ndefout = 3; /* number of defined symbols output */
/* storage of types */
int ntypes; /* number of types defined */
char * typeset[NTYPES]; /* pointers to type tags */
/* symbol tables for tokens and nonterminals */
int ntokens = 0;
struct toksymb tokset[NTERMS];
int toklev[NTERMS];
int nnonter = -1;
struct ntsymb nontrst[NNONTERM];
int start; /* start symbol */
/* assigned token type values */
int extval = 0;
/* input and output file descriptors */
FILE * finput; /* yacc input file */
FILE * faction; /* file for saving actions */
FILE * fdefine; /* file for # defines */
FILE * ftable; /* y.tab.c file */
FILE * ftemp; /* tempfile to pass 2 */
FILE * foutput; /* y.output file */
/* storage for grammar rules */
int mem0[MEMSIZE] ; /* production storage */
int *mem = mem0;
int nprod= 1; /* number of productions */
int *prdptr[NPROD]; /* pointers to descriptions of productions */
int levprd[NPROD] ; /* precedence levels for the productions */
setup(argc,argv) int argc; char *argv[];
{ int i,j,lev,t, ty;
int c;
int *p;
char actname[8];
foutput = NULL;
fdefine = NULL;
i = 1;
while( argc >= 2 && argv[1][0] == '-' ) {
while( *++(argv[1]) ){
switch( *argv[1] ){
case 'v':
case 'V':
foutput = fopen(FILEU, "w" );
if( foutput == NULL ) error( "cannot open y.output" );
continue;
case 'D':
case 'd':
fdefine = fopen( FILED, "w" );
continue;
case 'o':
case 'O':
fprintf( stderr, "`o' flag now default in yacc\n" );
continue;
case 'r':
case 'R':
error( "Ratfor Yacc is dead: sorry...\n" );
default:
error( "illegal option: %c", *argv[1]);
}
}
argv++;
argc--;
}
ftable = fopen( OFILE, "w" );
if( ftable == NULL ) error( "cannot open table file" );
ftemp = fopen( TEMPNAME, "w" );
faction = fopen( ACTNAME, "w" );
if( ftemp==NULL || faction==NULL ) error( "cannot open temp file" );
if( argc < 2 || ((finput=fopen( infile=argv[1], "r" )) == NULL ) ){
error( "cannot open input file" );
}
cnamp = cnames;
defin(0,"$end");
extval = 0400;
defin(0,"error");
defin(1,"$accept");
mem=mem0;
lev = 0;
ty = 0;
i=0;
/* sorry -- no yacc parser here.....
we must bootstrap somehow... */
for( t=gettok(); t!=MARK && t!= ENDFILE; ){
switch( t ){
case ';':
t = gettok();
break;
case START:
if( (t=gettok()) != IDENTIFIER ){
error( "bad %%start construction" );
}
start = chfind(1,tokname);
t = gettok();
continue;
case TYPEDEF:
if( (t=gettok()) != TYPENAME ) error( "bad syntax in %%type" );
ty = numbval;
for(;;){
t = gettok();
switch( t ){
case IDENTIFIER:
if( (t=chfind( 1, tokname ) ) < NTBASE ) {
j = TYPE( toklev[t] );
if( j!= 0 && j != ty ){
error( "type redeclaration of token %s",
tokset[t].name );
}
else SETTYPE( toklev[t],ty);
}
else {
j = nontrst[t-NTBASE].tvalue;
if( j != 0 && j != ty ){
error( "type redeclaration of nonterminal %s",
nontrst[t-NTBASE].name );
}
else nontrst[t-NTBASE].tvalue = ty;
}
case ',':
continue;
case ';':
t = gettok();
break;
default:
break;
}
break;
}
continue;
case UNION:
/* copy the union declaration to the output */
cpyunion();
t = gettok();
continue;
case LEFT:
case BINARY:
case RIGHT:
++i;
case TERM:
lev = t-TERM; /* nonzero means new prec. and assoc. */
ty = 0;
/* get identifiers so defined */
t = gettok();
if( t == TYPENAME ){ /* there is a type defined */
ty = numbval;
t = gettok();
}
for(;;) {
switch( t ){
case ',':
t = gettok();
continue;
case ';':
break;
case IDENTIFIER:
j = chfind(0,tokname);
if( lev ){
if( ASSOC(toklev[j]) ) error( "redeclaration of precedence of %s", tokname );
SETASC(toklev[j],lev);
SETPLEV(toklev[j],i);
}
if( ty ){
if( TYPE(toklev[j]) ) error( "redeclaration of type of %s", tokname );
SETTYPE(toklev[j],ty);
}
if( (t=gettok()) == NUMBER ){
tokset[j].value = numbval;
if( j < ndefout && j>2 ){
error( "please define type number of %s earlier",
tokset[j].name );
}
t=gettok();
}
continue;
}
break;
}
continue;
case LCURLY:
defout();
cpycode();
t = gettok();
continue;
default:
error( "syntax error" );
}
}
if( t == ENDFILE ){
error( "unexpected EOF before %%" );
}
/* t is MARK */
defout();
fprintf( ftable, "#define yyclearin yychar = -1\n" );
fprintf( ftable, "#define yyerrok yyerrflag = 0\n" );
fprintf( ftable, "extern int yychar;\nextern short yyerrflag;\n" );
fprintf( ftable, "#ifndef YYMAXDEPTH\n#define YYMAXDEPTH 150\n#endif\n" );
if( !ntypes ) fprintf( ftable, "#ifndef YYSTYPE\n#define YYSTYPE int\n#endif\n" );
fprintf( ftable, "YYSTYPE yylval, yyval;\n" );
prdptr[0]=mem;
/* added production */
*mem++ = NTBASE;
*mem++ = start; /* if start is 0, we will overwrite with the lhs of the first rule */
*mem++ = 1;
*mem++ = 0;
prdptr[1]=mem;
while( (t=gettok()) == LCURLY ) cpycode();
if( t != C_IDENTIFIER ) error( "bad syntax on first rule" );
if( !start ) prdptr[0][1] = chfind(1,tokname);
/* read rules */
while( t!=MARK && t!=ENDFILE ){
/* process a rule */
if( t == '|' ){
*mem++ = *prdptr[nprod-1];
}
else if( t == C_IDENTIFIER ){
*mem = chfind(1,tokname);
if( *mem < NTBASE ) error( "token illegal on LHS of grammar rule" );
++mem;
}
else error( "illegal rule: missing semicolon or | ?" );
/* read rule body */
t = gettok();
more_rule:
while( t == IDENTIFIER ) {
*mem = chfind(1,tokname);
if( *mem<NTBASE ) levprd[nprod] = toklev[*mem];
++mem;
t = gettok();
}
if( t == PREC ){
if( gettok()!=IDENTIFIER) error( "illegal %%prec syntax" );
j = chfind(2,tokname);
if( j>=NTBASE)error("nonterminal %s illegal after %%prec", nontrst[j-NTBASE].name);
levprd[nprod]=toklev[j];
t = gettok();
}
if( t == '=' ){
levprd[nprod] |= ACTFLAG;
fprintf( faction, "\ncase %d:", nprod );
cpyact( mem-prdptr[nprod]-1 );
fprintf( faction, " break;" );
if( (t=gettok()) == IDENTIFIER ){
/* action within rule... */
sprintf( actname, "$$%d", nprod );
j = chfind(1,actname); /* make it a nonterminal */
/* the current rule will become rule number nprod+1 */
/* move the contents down, and make room for the null */
for( p=mem; p>=prdptr[nprod]; --p ) p[2] = *p;
mem += 2;
/* enter null production for action */
p = prdptr[nprod];
*p++ = j;
*p++ = -nprod;
/* update the production information */
levprd[nprod+1] = levprd[nprod] & ~ACTFLAG;
levprd[nprod] = ACTFLAG;
if( ++nprod >= NPROD ) error( "more than %d rules", NPROD );
prdptr[nprod] = p;
/* make the action appear in the original rule */
*mem++ = j;
/* get some more of the rule */
goto more_rule;
}
}
while( t == ';' ) t = gettok();
*mem++ = -nprod;
/* check that default action is reasonable */
if( ntypes && !(levprd[nprod]&ACTFLAG) && nontrst[*prdptr[nprod]-NTBASE].tvalue ){
/* no explicit action, LHS has value */
register tempty;
tempty = prdptr[nprod][1];
if( tempty < 0 ) error( "must return a value, since LHS has a type" );
else if( tempty >= NTBASE ) tempty = nontrst[tempty-NTBASE].tvalue;
else tempty = TYPE( toklev[tempty] );
if( tempty != nontrst[*prdptr[nprod]-NTBASE].tvalue ){
error( "default action causes potential type clash" );
}
}
if( ++nprod >= NPROD ) error( "more than %d rules", NPROD );
prdptr[nprod] = mem;
levprd[nprod]=0;
}
/* end of all rules */
finact();
if( t == MARK ){
fprintf( ftable, "\n# line %d \"%s\"\n", lineno, infile );
while( (c=getc(finput)) != EOF ) putc( c, ftable );
}
fclose( finput );
}
finact(){
/* finish action routine */
fclose(faction);
fprintf( ftable, "# define YYERRCODE %d\n", tokset[2].value );
}
defin( t, s ) register char *s; {
/* define s to be a terminal if t=0
or a nonterminal if t=1 */
register val;
if (t) {
if( ++nnonter >= NNONTERM ) error("too many nonterminals, limit %d",NNONTERM);
nontrst[nnonter].name = cstash(s);
return( NTBASE + nnonter );
}
/* must be a token */
if( ++ntokens >= NTERMS ) error("too many terminals, limit %d",NTERMS );
tokset[ntokens].name = cstash(s);
/* establish value for token */
if( s[0]==' ' && s[2]=='\0' ) /* single character literal */
val = s[1];
else if ( s[0]==' ' && s[1]=='\\' ) { /* escape sequence */
if( s[3] == '\0' ){ /* single character escape sequence */
switch ( s[2] ){
/* character which is escaped */
case 'n': val = '\n'; break;
case 'r': val = '\r'; break;
case 'b': val = '\b'; break;
case 't': val = '\t'; break;
case 'f': val = '\f'; break;
case '\'': val = '\''; break;
case '"': val = '"'; break;
case '\\': val = '\\'; break;
default: error( "invalid escape" );
}
}
else if( s[2] <= '7' && s[2]>='0' ){ /* \nnn sequence */
if( s[3]<'0' || s[3] > '7' || s[4]<'0' ||
s[4]>'7' || s[5] != '\0' ) error("illegal \\nnn construction" );
val = 64*s[2] + 8*s[3] + s[4] - 73*'0';
if( val == 0 ) error( "'\\000' is illegal" );
}
}
else {
val = extval++;
}
tokset[ntokens].value = val;
toklev[ntokens] = 0;
return( ntokens );
}
defout(){ /* write out the defines (at the end of the declaration section) */
register int i, c;
register char *cp;
for( i=ndefout; i<=ntokens; ++i ){
cp = tokset[i].name;
if( *cp == ' ' ) ++cp; /* literals */
for( ; (c= *cp)!='\0'; ++cp ){
if( islower(c) || isupper(c) || isdigit(c) || c=='_' ); /* VOID */
else goto nodef;
}
fprintf( ftable, "# define %s %d\n", tokset[i].name, tokset[i].value );
if( fdefine != NULL ) fprintf( fdefine, "# define %s %d\n", tokset[i].name, tokset[i].value );
nodef: ;
}
ndefout = ntokens+1;
}
char *
cstash( s ) register char *s; {
char *temp;
temp = cnamp;
do {
if( cnamp >= &cnames[cnamsz] ) error("too many characters in id's and literals" );
else *cnamp++ = *s;
} while ( *s++ );
return( temp );
}
gettok() {
register i, base;
static int peekline; /* number of '\n' seen in lookahead */
register c, match, reserve;
begin:
reserve = 0;
lineno += peekline;
peekline = 0;
c = getc(finput);
while( c==' ' || c=='\n' || c=='\t' || c=='\f' ){
if( c == '\n' ) ++lineno;
c=getc(finput);
}
if( c == '/' ){ /* skip comment */
lineno += skipcom();
goto begin;
}
switch(c){
case EOF:
return(ENDFILE);
case '{':
ungetc( c, finput );
return( '=' ); /* action ... */
case '<': /* get, and look up, a type name (union member name) */
i = 0;
while( (c=getc(finput)) != '>' && c>=0 && c!= '\n' ){
tokname[i] = c;
if( ++i >= NAMESIZE ) --i;
}
if( c != '>' ) error( "unterminated < ... > clause" );
tokname[i] = '\0';
for( i=1; i<=ntypes; ++i ){
if( !strcmp( typeset[i], tokname ) ){
numbval = i;
return( TYPENAME );
}
}
typeset[numbval = ++ntypes] = cstash( tokname );
return( TYPENAME );
case '"':
case '\'':
match = c;
tokname[0] = ' ';
i = 1;
for(;;){
c = getc(finput);
if( c == '\n' || c == EOF )
error("illegal or missing ' or \"" );
if( c == '\\' ){
c = getc(finput);
tokname[i] = '\\';
if( ++i >= NAMESIZE ) --i;
}
else if( c == match ) break;
tokname[i] = c;
if( ++i >= NAMESIZE ) --i;
}
break;
case '%':
case '\\':
switch(c=getc(finput)) {
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( isdigit(c) ){ /* number */
numbval = c-'0' ;
base = (c=='0') ? 8 : 10 ;
for( c=getc(finput); isdigit(c) ; c=getc(finput) ){
numbval = numbval*base + c - '0';
}
ungetc( c, finput );
return(NUMBER);
}
else if( islower(c) || isupper(c) || c=='_' || c=='.' || c=='$' ){
i = 0;
while( islower(c) || isupper(c) || isdigit(c) || c=='_' || c=='.' || c=='$' ){
tokname[i] = c;
if( reserve && isupper(c) ) tokname[i] += 'a'-'A';
if( ++i >= NAMESIZE ) --i;
c = getc(finput);
}
}
else return(c);
ungetc( c, finput );
}
tokname[i] = '\0';
if( reserve ){ /* find a reserved word */
if( !strcmp(tokname,"term")) return( TERM );
if( !strcmp(tokname,"token")) return( TERM );
if( !strcmp(tokname,"left")) return( LEFT );
if( !strcmp(tokname,"nonassoc")) return( BINARY );
if( !strcmp(tokname,"binary")) return( BINARY );
if( !strcmp(tokname,"right")) return( RIGHT );
if( !strcmp(tokname,"prec")) return( PREC );
if( !strcmp(tokname,"start")) return( START );
if( !strcmp(tokname,"type")) return( TYPEDEF );
if( !strcmp(tokname,"union")) return( UNION );
error("invalid escape, or illegal reserved word: %s", tokname );
}
/* look ahead to distinguish IDENTIFIER from C_IDENTIFIER */
c = getc(finput);
while( c==' ' || c=='\t'|| c=='\n' || c=='\f' || c== '/' ) {
if( c == '\n' ) ++peekline;
else if( c == '/' ){ /* look for comments */
peekline += skipcom();
}
c = getc(finput);
}
if( c == ':' ) return( C_IDENTIFIER );
ungetc( c, finput );
return( IDENTIFIER );
}
fdtype( t ){ /* determine the type of a symbol */
register v;
if( t >= NTBASE ) v = nontrst[t-NTBASE].tvalue;
else v = TYPE( toklev[t] );
if( v <= 0 ) error( "must specify type for %s", (t>=NTBASE)?nontrst[t-NTBASE].name:
tokset[t].name );
return( v );
}
chfind( t, s ) register char *s; {
int i;
if (s[0]==' ')t=0;
TLOOP(i){
if(!strcmp(s,tokset[i].name)){
return( i );
}
}
NTLOOP(i){
if(!strcmp(s,nontrst[i].name)) {
return( i+NTBASE );
}
}
/* cannot find name */
if( t>1 )
error( "%s should have been defined earlier", s );
return( defin( t, s ) );
}
cpyunion(){
/* copy the union declaration to the output, and the define file if present */
int level, c;
fprintf( ftable, "\n# line %d \"%s\"\n", lineno, infile );
fprintf( ftable, "typedef union " );
if( fdefine ) fprintf( fdefine, "\ntypedef union " );
level = 0;
for(;;){
if( (c=getc(finput)) < 0 ) error( "EOF encountered while processing %%union" );
putc( c, ftable );
if( fdefine ) putc( c, fdefine );
switch( c ){
case '\n':
++lineno;
break;
case '{':
++level;
break;
case '}':
--level;
if( level == 0 ) { /* we are finished copying */
fprintf( ftable, " YYSTYPE;\n" );
if( fdefine ) fprintf( fdefine, " YYSTYPE;\nextern YYSTYPE yylval;\n" );
return;
}
}
}
}
cpycode(){ /* copies code between \{ and \} */
int c;
c = getc(finput);
if( c == '\n' ) {
c = getc(finput);
lineno++;
}
fprintf( ftable, "\n# line %d \"%s\"\n", lineno, infile );
while( c>=0 ){
if( c=='\\' )
if( (c=getc(finput)) == '}' ) return;
else putc('\\', ftable );
if( c=='%' )
if( (c=getc(finput)) == '}' ) return;
else putc('%', ftable );
putc( c , ftable );
if( c == '\n' ) ++lineno;
c = getc(finput);
}
error("eof before %%}" );
}
skipcom(){ /* skip over comments */
register c, i=0; /* i is the number of lines skipped */
/* skipcom is called after reading a / */
if( getc(finput) != '*' ) error( "illegal comment" );
c = getc(finput);
while( c != EOF ){
while( c == '*' ){
if( (c=getc(finput)) == '/' ) return( i );
}
if( c == '\n' ) ++i;
c = getc(finput);
}
error( "EOF inside comment" );
/* NOTREACHED */
}
cpyact(offset){ /* copy C action to the next ; or closing } */
int brac, c, match, j, s, tok;
fprintf( faction, "\n# line %d \"%s\"\n", lineno, infile );
brac = 0;
loop:
c = getc(finput);
swt:
switch( c ){
case ';':
if( brac == 0 ){
putc( c , faction );
return;
}
goto lcopy;
case '{':
brac++;
goto lcopy;
case '$':
s = 1;
tok = -1;
c = getc(finput);
if( c == '<' ){ /* type description */
ungetc( c, finput );
if( gettok() != TYPENAME ) error( "bad syntax on $<ident> clause" );
tok = numbval;
c = getc(finput);
}
if( c == '$' ){
fprintf( faction, "yyval");
if( ntypes ){ /* put out the proper tag... */
if( tok < 0 ) tok = fdtype( *prdptr[nprod] );
fprintf( faction, ".%s", typeset[tok] );
}
goto loop;
}
if( c == '-' ){
s = -s;
c = getc(finput);
}
if( isdigit(c) ){
j=0;
while( isdigit(c) ){
j= j*10+c-'0';
c = getc(finput);
}
j = j*s - offset;
if( j > 0 ){
error( "Illegal use of $%d", j+offset );
}
fprintf( faction, "yypvt[-%d]", -j );
if( ntypes ){ /* put out the proper tag */
if( j+offset <= 0 && tok < 0 ) error( "must specify type of $%d", j+offset );
if( tok < 0 ) tok = fdtype( prdptr[nprod][j+offset] );
fprintf( faction, ".%s", typeset[tok] );
}
goto swt;
}
putc( '$' , faction );
if( s<0 ) putc('-', faction );
goto swt;
case '}':
if( --brac ) goto lcopy;
putc( c, faction );
return;
case '/': /* look for comments */
putc( c , faction );
c = getc(finput);
if( c != '*' ) goto swt;
/* it really is a comment */
putc( c , faction );
c = getc(finput);
while( c != EOF ){
while( c=='*' ){
putc( c , faction );
if( (c=getc(finput)) == '/' ) goto lcopy;
}
putc( c , faction );
if( c == '\n' )++lineno;
c = getc(finput);
}
error( "EOF inside comment" );
case '\'': /* character constant */
match = '\'';
goto string;
case '"': /* character string */
match = '"';
string:
putc( c , faction );
while( c=getc(finput) ){
if( c=='\\' ){
putc( c , faction );
c=getc(finput);
if( c == '\n' ) ++lineno;
}
else if( c==match ) goto lcopy;
else if( c=='\n' ) error( "newline in string or char. const." );
putc( c , faction );
}
error( "EOF in string or character constant" );
case EOF:
error("action does not terminate" );
case '\n': ++lineno;
goto lcopy;
}
lcopy:
putc( c , faction );
goto loop;
}
Continuous source code history from original PDP-7 UNIX to FreeBSD 2, the first fully unencumbered FreeBSD release.