int ungetc(int c, FILE *f){
if(c==EOF) return EOF;
switch(f->state){
default: /* WR */
f->state=ERR;
return EOF;
case CLOSED:
case ERR:
return EOF;
case OPEN:
_IO_setvbuf(f);
case RDWR:
case END:
f->wp=f->buf;
if(f->bufl==0)
f->wp += 1;
else
f->wp += f->bufl;
f->rp = f->wp;
f->state=RD;
case RD:
if(f->rp==f->buf) return EOF;
if(f->flags&STRING)
f->rp--;
else
*--f->rp=c;
return (char)c;
}
}
int _IO_getc(FILE *f){
int cnt, n;
switch(f->state){
default: /* CLOSED, WR, ERR, EOF */
return EOF;
case OPEN:
_IO_setvbuf(f);
case RDWR:
case RD:
if(f->flags&STRING) return EOF;
if(f->buf == f->unbuf)
n = 1;
else
n = f->bufl;
cnt=read(f->fd, f->buf, n);
switch(cnt){
case -1: f->state=ERR; return EOF;
case 0: f->state=END; return EOF;
default:
f->state=RD;
f->rp=f->buf;
f->wp=f->buf+cnt;
return (*f->rp++)&_IO_CHMASK;
}
}
}
void
setlinebuf (_IO_FILE *stream)
{
_IO_setvbuf (stream, NULL, 1, 0);
}
/*
* Look this over for simplification
*/
int _IO_putc(int c, FILE *f){
int cnt;
static int first=1;
switch(f->state){
case RD:
f->state=ERR;
case ERR:
case CLOSED:
return EOF;
case OPEN:
_IO_setvbuf(f);
/* fall through */
case RDWR:
case END:
f->rp=f->buf+f->bufl;
if(f->flags&LINEBUF){
f->wp=f->rp;
f->lp=f->buf;
}
else
f->wp=f->buf;
break;
}
if(first){
atexit(_IO_cleanup);
first=0;
}
if(f->flags&STRING){
f->rp=f->buf+f->bufl;
if(f->wp==f->rp){
if(f->flags&BALLOC)
f->buf=realloc(f->buf, f->bufl+BUFSIZ);
else{
f->state=ERR;
return EOF;
}
if(f->buf==NULL){
f->state=ERR;
return EOF;
}
f->rp=f->buf+f->bufl;
f->bufl+=BUFSIZ;
}
*f->wp++=c;
}
else if(f->flags&LINEBUF){
if(f->lp==f->rp){
cnt=f->lp-f->buf;
if(f->flags&APPEND) lseek(f->fd, 0L, SEEK_END);
if(cnt!=0 && write(f->fd, f->buf, cnt)!=cnt){
f->state=ERR;
return EOF;
}
f->lp=f->buf;
}
*f->lp++=c;
if(c=='\n'){
cnt=f->lp-f->buf;
if(f->flags&APPEND) lseek(f->fd, 0L, SEEK_END);
if(cnt!=0 && write(f->fd, f->buf, cnt)!=cnt){
f->state=ERR;
return EOF;
}
f->lp=f->buf;
}
}
else if(f->buf==f->unbuf){
f->unbuf[0]=c;
if(f->flags&APPEND) lseek(f->fd, 0L, SEEK_END);
if(write(f->fd, f->buf, 1)!=1){
f->state=ERR;
return EOF;
}
}
else{
if(f->wp==f->rp){
cnt=f->wp-f->buf;
if(f->flags&APPEND) lseek(f->fd, 0L, SEEK_END);
if(cnt!=0 && write(f->fd, f->buf, cnt)!=cnt){
f->state=ERR;
return EOF;
}
f->wp=f->buf;
f->rp=f->buf+f->bufl;
}
*f->wp++=c;
}
f->state=WR;
/*
* Make sure EOF looks different from putc(-1)
* Should be able to cast to unsigned char, but
* there's a vc bug preventing that from working
*/
return c&0xff;
}
