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yylex.c
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C/C++ Source or Header
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1980-02-17
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6KB
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349 lines
/* Copyright (c) 1979 Regents of the University of California */
#
/*
* pi - Pascal interpreter code translator
*
* Charles Haley, Bill Joy UCB
* Version 1.2 January 1979
*
*
* pxp - Pascal execution profiler
*
* Bill Joy UCB
* Version 1.2 January 1979
*/
#include "0.h"
#include "yy.h"
/*
* Scanner
*/
int yylacnt;
#define YYLASIZ 10
struct yytok Yla[YYLASIZ];
unyylex(y)
struct yylex *y;
{
if (yylacnt == YYLASIZ)
panic("unyylex");
copy(&Yla[yylacnt], y, sizeof Yla[0]);
yylacnt++;
}
yylex()
{
register c;
register **ip;
register char *cp;
int f;
char delim;
if (yylacnt != 0) {
yylacnt--;
copy(&Y, &Yla[yylacnt], sizeof Y);
return (yychar);
}
if (c = yysavc)
yysavc = 0;
else
c = getchar();
#ifdef PXP
yytokcnt++;
#endif
next:
/*
* skip white space
*/
#ifdef PXP
yywhcnt = 0;
#endif
while (c == ' ' || c == '\t') {
#ifdef PXP
if (c == '\t')
yywhcnt++;
yywhcnt++;
#endif
c = getchar();
}
yyecol = yycol;
yyeline = yyline;
yyefile = filename;
yyeseqid = yyseqid;
yyseekp = yylinpt;
cp = token;
yylval = yyline;
switch (c) {
case 'a': case 'b': case 'c': case 'd': case 'e': case 'f': case 'g':
case 'h': case 'i': case 'j': case 'k': case 'l': case 'm': case 'n':
case 'o': case 'p': case 'q': case 'r': case 's': case 't': case 'u':
case 'v': case 'w': case 'x': case 'y': case 'z':
case 'A': case 'B': case 'C': case 'D': case 'E': case 'F': case 'G':
case 'H': case 'I': case 'J': case 'K': case 'L': case 'M': case 'N':
case 'O': case 'P': case 'Q': case 'R': case 'S': case 'T': case 'U':
case 'V': case 'W': case 'X': case 'Y': case 'Z':
do {
*cp++ = c;
c = getchar();
} while (alph(c) || digit(c));
*cp = 0;
if (opt('s'))
for (cp = token; *cp; cp++)
if (*cp >= 'A' && *cp <= 'Z') {
*cp =| ' ';
}
yysavc = c;
ip = hash(0, 1);
if (*ip < yykey || *ip >= lastkey) {
yylval = *ip;
return (YID);
}
yylval = yyline;
/*
* For keywords
* the lexical token
* is magically retrieved
* from the keyword table.
*/
return ((*ip)[1]);
case '0': case '1': case '2': case '3': case '4':
case '5': case '6': case '7': case '8': case '9':
f = 0;
do {
*cp++ = c;
c = getchar();
} while (digit(c));
if (c == 'b' || c == 'B') {
/*
* nonstandard - octal constants
*/
if (opt('s')) {
standard();
yerror("Octal constants are non-standard");
}
*cp = 0;
yylval = copystr(token);
return (YBINT);
}
if (c == '.') {
c = getchar();
if (c == '.') {
*cp = 0;
yysavc = YDOTDOT;
yylval = copystr(token);
return (YINT);
}
infpnumb:
f++;
*cp++ = '.';
if (!digit(c)) {
yyset();
recovered();
yerror("Digits required after decimal point");
*cp++ = '0';
} else
while (digit(c)) {
*cp++ = c;
c = getchar();
}
}
if (c == 'e' || c == 'E') {
f++;
*cp++ = c;
if ((c = yysavc) == 0)
c = getchar();
if (c == '+' || c == '-') {
*cp++ = c;
c = getchar();
}
if (!digit(c)) {
yyset();
yerror("Digits required in exponent");
*cp++ = '0';
} else
while (digit(c)) {
*cp++ = c;
c = getchar();
}
}
*cp = 0;
yysavc = c;
yylval = copystr(token);
if (f)
return (YNUMB);
return (YINT);
case '"':
case '`':
if (!any(bufp + 1, c))
goto illch;
if (!dquote) {
recovered();
dquote++;
yerror("Character/string delimiter is '");
}
case '\'':
case '#':
delim = c;
do {
do {
c = getchar();
if (c == '\n') {
yerror("Unmatched %c for string", delim);
if (cp == token)
*cp++ = ' ', cp++;
break;
}
*cp++ = c;
} while (c != delim);
c = getchar();
} while (c == delim);
*--cp = 0;
if (cp == token) {
yerror("Null string not allowed");
*cp++ = ' ';
*cp++ = 0;
}
yysavc = c;
yylval = copystr(token);
return (YSTRING);
case '.':
c = getchar();
if (c == '.')
return (YDOTDOT);
if (digit(c)) {
recovered();
yerror("Digits required before decimal point");
*cp++ = '0';
goto infpnumb;
}
yysavc = c;
return ('.');
case '{':
/*
* { ... } comment
*/
#ifdef PXP
getcm(c);
#endif
#ifdef PI
c = options();
while (c != '}') {
if (c <= 0)
goto nonterm;
if (c == '{') {
warning();
yyset();
yerror("{ in a { ... } comment");
}
c = getchar();
}
#endif
c = getchar();
goto next;
case '(':
if ((c = getchar()) == '*') {
/*
* (* ... *) comment
*/
#ifdef PXP
getcm(c);
c = getchar();
goto next;
#endif
#ifdef PI
c = options();
for (;;) {
if (c < 0) {
nonterm:
yerror("Comment does not terminate - QUIT");
pexit(ERRS);
}
if (c == '(' && (c = getchar()) == '*') {
warning();
yyset();
yerror("(* in a (* ... *) comment");
}
if (c == '*') {
if ((c = getchar()) != ')')
continue;
c = getchar();
goto next;
}
c = getchar();
}
#endif
}
yysavc = c;
c = '(';
case ';':
case ',':
case ':':
case '=':
case '*':
case '+':
case '/':
case '-':
case '|':
case '&':
case ')':
case '[':
case ']':
case '<':
case '>':
case '~':
case '^':
return (c);
default:
switch (c) {
case YDOTDOT:
return (c);
case '\n':
c = getchar();
#ifdef PXP
yytokcnt++;
#endif
goto next;
case '\f':
c = getchar();
goto next;
}
if (c <= 0)
return (YEOF);
illch:
do
yysavc = getchar();
while (yysavc == c);
yylval = c;
return (YILLCH);
}
}
yyset()
{
yyecol = yycol;
yyeline = yyline;
yyefile = filename;
yyseekp = yylinpt;
}
/*
* Setuflg trims the current
* input line to at most 72 chars
* for the u option.
*/
setuflg()
{
if (charbuf[71] != '\n') {
charbuf[72] = '\n';
charbuf[73] = 0;
}
}