gettok()
{
register i, base;
register c, match, reserve;
begin:
reserve = 0;
lineno += peekline;
peekline = 0;
c = unix_getc(finput);
while( c==' ' || c=='\n' || c=='\t' || c=='\f' || c=='\r')
{
if( c == '\n' ) ++lineno;
c=unix_getc(finput);
}
if( c == '/' )
{
/* skip comment */
lineno += skipcom();
goto begin;
}
switch(c)
{
case -1: /* EOF */
return(ENDFILE);
case '{':
ungetc( c, finput );
return( '=' ); /* action ... */
case '<': /* get, and look up, a type name (union member name) */
i = 0;
while( (c=unix_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 = unix_getc(finput);
if( c == '\n' || c == EOF )
error("illegal or missing ' or \"" );
if( c == '\\' )
{
c = unix_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=unix_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=unix_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 = unix_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 = unix_getc(finput);
while( c==' ' || c=='\t'|| c=='\n' || c=='\f' || c== '/' )
{
if( c == '\n' ) ++peekline;
else if( c == '/' )
{
/* look for comments */
peekline += skipcom();
}
c = unix_getc(finput);
}
if( c == ':' ) return( C_IDENTIFIER );
ungetc( c, finput );
return( IDENTIFIER );
}
int yylex(void)
{
char errmsg[80];
int keyword, c;
loop:
skipws();
xline = line;
xcolumn = column;
if (ch == '/')
{
getch();
if (ch == '/')
{
skipcom();
goto loop;
}
return '/';
}
if (ch == EOF)
return EOF;
if (isalpha(ch))
{
getword();
keyword = lookup(wbuf);
wpos = 0;
if (keyword >= 0)
return keyword;
snprintf(yylval.name, BUFSIZ, "%s", wbuf);
return LIDENT;
}
if (isdigit(ch))
{
getnum();
yylval.val = atoi(wbuf);
wpos = 0;
return LNUMBER;
}
c = ch;
getch();
if (c == '#')
{
gethex();
yylval.val = hex(wbuf+1);
wpos = 0;
return LHEX;
}
switch (c)
{
case '+':
case '-':
case '{':
case '}':
case ',':
case '*':
case '%':
case '|':
case '&':
case '^':
case '~':
case '(':
case ')':
return c;
}
snprintf(errmsg, sizeof(errmsg), "unknown symbol: %c", c);
yyerror(errmsg);
return 0;
}
