kolibrios/programs/develop/scc/cc2.c
jacekm 1967c25fac scc 0.5.3
git-svn-id: svn://kolibrios.org@718 a494cfbc-eb01-0410-851d-a64ba20cac60
2008-02-08 11:41:42 +00:00

558 lines
11 KiB
C

/*
** Small-C Compiler -- Part 2 -- Front End and Miscellaneous.
** Copyright 1982, 1983, 1985, 1988 J. E. Hendrix
** Copyright 1998 H T Walheim
** All rights reserved.
*/
#include <stdio.h>
#include "cc.h"
extern char
*symtab, *macn, *macq, *pline, *mline, optimize,
alarm, *glbptr, *line, *lptr, *cptr, *cptr2, *cptr3,
*locptr, msname[NAMESIZE], pause, quote[2];
extern int
*wq, ccode, ch, csp, eof, errflag, iflevel,
input, input2, listfp, macptr, nch,
nxtlab, op[16], opindex, opsize, output, pptr,
skiplevel, *wqptr;
/********************** input functions **********************/
preprocess() {
int k;
char c;
if(ccode) {
line = mline;
ifline();
if(eof) return;
}
else {
inline();
return;
}
pptr = -1;
while(ch != NEWLINE && ch) {
if(white()) {
keepch(' ');
while(white()) gch();
}
else if(ch == '"') {
keepch(ch);
gch();
while(ch != '"' || (*(lptr-1) == 92 && *(lptr-2) != 92)) {
if(ch == NULL) {
error("no quote");
break;
}
keepch(gch());
}
gch();
keepch('"');
}
else if(ch == 39) {
keepch(39);
gch();
while(ch != 39 || (*(lptr-1) == 92 && *(lptr-2) != 92)) {
if(ch == NULL) {
error("no apostrophe");
break;
}
keepch(gch());
}
gch();
keepch(39);
}
else if(ch == '/' && nch == '*')
{
bump(2);
while((ch == '*' && nch == '/') == 0)
{
if(ch)
bump(1);
else
{
ifline();
if(eof)
break;
}
}
bump(2);
}
else if(ch == '/' && nch == '/')
{
bump(2);
while(ch != NEWLINE)
{
if(ch)
bump(1);
else
{
if(eof)
break;
}
}
bump(1);
}
else if(an(ch)) {
k = 0;
while(an(ch) && k < NAMEMAX) {
msname[k++] = ch;
gch();
}
msname[k] = NULL;
if(search(msname, macn, NAMESIZE+2, MACNEND, MACNBR, 0)) {
k = getint(cptr+NAMESIZE, 2/*INTSIZE*/);
while(c = macq[k++]) keepch(c);
while(an(ch)) gch();
}
else {
k = 0;
while(c = msname[k++]) keepch(c);
}
}
else keepch(gch());
}
if(pptr >= LINEMAX) error("line too long");
keepch(NULL);
line = pline;
bump(0);
}
keepch(c) char c; {
if(pptr < LINEMAX) pline[++pptr] = c;
}
ifline() {
while(1) {
inline();
if(eof) return;
if(match("#ifdef")) {
++iflevel;
if(skiplevel) continue;
symname(msname);
if(search(msname, macn, NAMESIZE+2, MACNEND, MACNBR, 0) == 0)
skiplevel = iflevel;
continue;
}
if(match("#ifndef")) {
++iflevel;
if(skiplevel) continue;
symname(msname);
if(search(msname, macn, NAMESIZE+2, MACNEND, MACNBR, 0))
skiplevel = iflevel;
continue;
}
if(match("#else")) {
if(iflevel) {
if(skiplevel == iflevel) skiplevel = 0;
else if(skiplevel == 0) skiplevel = iflevel;
}
else noiferr();
continue;
}
if(match("#endif")) {
if(iflevel) {
if(skiplevel == iflevel) skiplevel = 0;
--iflevel;
}
else noiferr();
continue;
}
if(skiplevel) continue;
if(ch == 0) continue;
break;
}
}
inline() { /* numerous revisions */
int k, unit;
if(input == EOF) openfile();
if(eof) return;
if((unit = input2) == EOF) unit = input;
if(fgets(line, LINEMAX, unit) == NULL) {
fclose(unit);
if(input2 != EOF)
input2 = EOF;
else input = EOF;
*line = NULL;
}
else if(listfp)
{
if(listfp == output) fputc(';', output);
fputs(line, listfp);
}
#ifdef _MSC_VER
else
{
fputc(';', output);
fputs(line, output);
}
#endif
bump(0);
}
inbyte() {
while(ch == 0) {
if(eof) return 0;
preprocess();
}
return gch();
}
/********************* scanning functions ********************/
/*
** test if next input string is legal symbol name
*/
symname(sname) char *sname; {
int k;char c;
blanks();
if(alpha(ch) == 0) return (*sname = 0);
k = 0;
while(an(ch)) {
sname[k] = gch();
if(k < NAMEMAX) ++k;
}
sname[k] = 0;
return 1;
}
need(str) char *str; {
if(match(str) == 0) error("missing token");
}
ns() {
if(match(";") == 0) error("no semicolon");
else errflag = 0;
}
match(lit) char *lit; {
int k;
blanks();
if(k = streq(lptr, lit)) {
bump(k);
return 1;
}
return 0;
}
streq(str1, str2) char str1[], str2[]; {
int k;
k = 0;
while (str2[k]) {
if(str1[k] != str2[k]) return 0;
++k;
}
return k;
}
amatch(lit, len) char *lit; int len; {
int k;
blanks();
if(k = astreq(lptr, lit, len)) {
bump(k);
return 1;
}
return 0;
}
astreq(str1, str2, len) char str1[], str2[]; int len; {
int k;
k = 0;
while (k < len) {
if(str1[k] != str2[k]) break;
/*
** must detect end of symbol table names terminated by
** symbol length in binary
*/
if(str2[k] < ' ') break;
if(str1[k] < ' ') break;
++k;
}
if(an(str1[k]) || an(str2[k])) return 0;
return k;
}
nextop(list) char *list; {
char op[4];
opindex = 0;
blanks();
while(1) {
opsize = 0;
while(*list > ' ') op[opsize++] = *list++;
op[opsize] = 0;
if(opsize = streq(lptr, op))
if(*(lptr+opsize) != '=' &&
*(lptr+opsize) != *(lptr+opsize-1))
return 1;
if(*list) {
++list;
++opindex;
}
else return 0;
}
}
blanks() {
while(1) {
while(ch) {
if(white()) gch();
else return;
}
if(line == mline) return;
preprocess();
if(eof) break;
}
}
white() {
return (*lptr <= ' ' && *lptr);
}
gch() {
int c;
if(c = ch) bump(1);
return c;
}
bump(n) int n; {
if(n) lptr += n;
else lptr = line;
if(ch = nch = *lptr) nch = *(lptr+1);
}
kill() {
*line = 0;
bump(0);
}
skip() {
if(an(inbyte()))
while(an(ch)) gch();
else while(an(ch) == 0) {
if(ch == 0) break;
gch();
}
blanks();
}
endst() {
blanks();
return (streq(lptr, ";") || ch == 0);
}
/*********** symbol table management functions ***********/
addsym(sname, id, type, size, value, lgpp, class)
char *sname, id, type;
int size, value, *lgpp, class;
{
if(lgpp == &glbptr)
{
if(cptr2 = findglb(sname))
return cptr2;
if(cptr == 0)
{
error("global symbol table overflow");
return 0;
}
}
else
{
if(locptr > (ENDLOC-SYMMAX))
{
error("local symbol table overflow");
exit(ERRCODE);
}
cptr = *lgpp;
}
cptr[IDENT] = id;
cptr[TYPE] = type;
cptr[CLASS] = class;
putint(size, cptr + SIZE, INTSIZE);
putint(value, cptr + OFFSET, INTSIZE);
cptr3 = cptr2 = cptr + NAME;
while(an(*sname))
*cptr2++ = *sname++;
if(lgpp == &locptr)
{
*cptr2 = cptr2 - cptr3; /* set length */
*lgpp = ++cptr2;
}
return cptr;
}
/*
** search for symbol match
** on return cptr points to slot found or empty slot
*/
search(sname, buf, len, end, max, off)
char *sname, *buf, *end; int len, max, off; {
cptr =
cptr2 = buf+((hash(sname)%(max-1))*len);
while(*cptr != NULL) {
if(astreq(sname, cptr+off, NAMEMAX)) return 1;
if((cptr = cptr+len) >= end) cptr = buf;
if(cptr == cptr2) return (cptr = 0);
}
return 0;
}
hash(sname) char *sname; {
int i, c;
i = 0;
while(c = *sname++) i = (i << 1) + c;
return i;
}
findglb(sname) char *sname; {
if(search(sname, STARTGLB, SYMMAX, ENDGLB, NUMGLBS, NAME))
return cptr;
return 0;
}
findloc(sname) char *sname; {
cptr = locptr - 1; /* search backward for block locals */
while(cptr > STARTLOC) {
cptr = cptr - *cptr;
if(astreq(sname, cptr, NAMEMAX)) return (cptr - NAME);
cptr = cptr - NAME - 1;
}
return 0;
}
nextsym(entry) char *entry; {
entry = entry + NAME;
while(*entry++ >= ' '); /* find length byte */
return entry;
}
/******** while queue management functions *********/
addwhile(ptr) int ptr[]; {
int k;
ptr[WQSP] = csp; /* and stk ptr */
ptr[WQLOOP] = getlabel(); /* and looping label */
ptr[WQEXIT] = getlabel(); /* and exit label */
if(wqptr == WQMAX) {
error("control statement nesting limit");
exit(ERRCODE);
}
k = 0;
while (k < WQSIZ) *wqptr++ = ptr[k++];
}
readwhile(ptr) int *ptr; {
if(ptr <= wq) {
error("out of context");
return 0;
}
else return (ptr - WQSIZ);
}
delwhile() {
if(wqptr > wq) wqptr -= WQSIZ;
}
/****************** utility functions ********************/
/*
** test if c is alphabetic
*/
alpha(c) char c; {
return (isalpha(c) || c == '_');
}
/*
** test if given character is alphanumeric
*/
an(c) char c; {
return (alpha(c) || isdigit(c));
}
/*
** return next avail internal label number
*/
getlabel() {
return(++nxtlab);
}
/*
** get integer of length len from address addr
** (byte sequence set by "putint")
*/
getint(addr, len) char *addr; int len; {
int i;
i = *(addr + --len); /* high order byte sign extended */
while(len--) i = (i << 8) | *(addr + len) & 255;
return i;
}
/*
** put integer i of length len into address addr
** (low byte first)
*/
putint(i, addr, len) char *addr; int i, len; {
while(len--) {
*addr++ = i;
i = i >> 8;
}
}
lout(line, fd) char *line; int fd; {
fputs(line, fd);
fputc(NEWLINE, fd);
}
/******************* error functions *********************/
illname() {
error("illegal symbol");
skip();
}
multidef(sname) char *sname; {
error("already defined");
}
needlval() {
error("must be lvalue");
}
noiferr() {
error("no matching #if...");
errflag = 0;
}
error(msg)
char msg[];
{
if(errflag)
return;
else
errflag = 1;
lout(line, stderr);
errout(msg, stderr);
if(alarm)
fputc(7, stderr);
if(pause)
while(fgetc(stderr) != NEWLINE);
if(listfp > 0)
errout(msg, listfp);
}
errout(msg, fp) char msg[]; int fp; {
int k;
k = line+2;
while(k++ <= lptr) fputc(' ', fp);
lout("/\\", fp);
fputs("**** ", fp); lout(msg, fp);
}