/***********************************************************************
* *
* This software is part of the ast package *
* Copyright (c) 1989-2011 AT&T Intellectual Property *
* and is licensed under the *
* Eclipse Public License, Version 1.0 *
* by AT&T Intellectual Property *
* *
* A copy of the License is available at *
* http://www.eclipse.org/org/documents/epl-v10.html *
* (with md5 checksum b35adb5213ca9657e911e9befb180842) *
* *
* Information and Software Systems Research *
* AT&T Research *
* Florham Park NJ *
* *
* Glenn Fowler <gsf@research.att.com> *
* David Korn <dgk@research.att.com> *
* Eduardo Krell <ekrell@adexus.cl> *
* *
***********************************************************************/
#pragma prototyped
#include "3d.h"
#include <cs.h>
/*
* peek siz chars from fd into buf
* if not peekable but seekable then chars are peeked at offset 0
*/
ssize_t
peek(int fd, void* buf, size_t siz)
{
register int n;
n = cspeek(&cs, fd, buf, siz);
if (n >= 0)
return(n);
cspeek(&cs, -1, NiL, 0);
if (!FSTAT(fd, &state.path.st) && state.path.st.st_size <= siz)
{
while ((n = read(fd, buf, siz)) != state.path.st.st_size && lseek(fd, 0L, 1) > 0 && lseek(fd, 0L, 0) == 0);
if (n == state.path.st.st_size || n > 0 && !state.path.st.st_size)
return(n);
}
return(-1);
}