blob: 471ab7e33bd46adf953a1386fa2753fc876e2010 (
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#include <errno.h>
#include <unistd.h>
#include <string.h>
#include "lib.h"
#include "sys9.h"
#include <stdio.h>
ssize_t
read(int d, void *buf, size_t nbytes)
{
int n, noblock, isbuf;
Fdinfo *f;
if(d<0 || d>=OPEN_MAX || !((f = &_fdinfo[d])->flags&FD_ISOPEN)){
errno = EBADF;
return -1;
}
if(nbytes <= 0)
return 0;
if(buf == 0){
errno = EFAULT;
return -1;
}
f = &_fdinfo[d];
noblock = f->oflags&O_NONBLOCK;
isbuf = f->flags&(FD_BUFFERED|FD_BUFFEREDX);
if(noblock || isbuf){
if(f->flags&FD_BUFFEREDX) {
errno = EIO;
return -1;
}
if(!isbuf) {
if(_startbuf(d) != 0) {
errno = EIO;
return -1;
}
}
n = _readbuf(d, buf, nbytes, noblock);
}else{
n = _READ(d, buf, nbytes);
if(n < 0)
_syserrno();
}
return n;
}
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