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/*-
* Copyright (c) 1990, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Chris Torek.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#if defined(LIBC_SCCS) && !defined(lint)
#if 0
static char sccsid
[] = "@(#)fvwrite.c 8.1 (Berkeley) 6/4/93";
#endif
static const char rcsid
[] =
"$\Id: fvwrite.c,v 1.3 1996/06/22 10:33:27 jraynard Exp $";
#endif /* LIBC_SCCS and not lint */
#include <stdio.h>
#include <string.h>
#include "local.h"
#include "fvwrite.h"
/*
* Write some memory regions. Return zero on success, EOF on error.
*
* This routine is large and unsightly, but most of the ugliness due
* to the three different kinds of output buffering is handled here.
*/
int
__sfvwrite
(fp
, uio
)
register FILE
*fp
;
register struct __suio
*uio
;
{
register size_t len
;
register char *p
;
register struct __siov
*iov
;
register int w
, s
;
char *nl
;
int nlknown
, nldist
;
if ((len
= uio
->uio_resid
) == 0)
return (0);
/* make sure we can write */
if (cantwrite
(fp
))
return (EOF
);
#define MIN(a, b) ((a) < (b) ? (a) : (b))
#define COPY(n) (void)memcpy((void *)fp->_p, (void *)p, (size_t)(n))
iov
= uio
->uio_iov
;
p
= iov
->iov_base
;
len
= iov
->iov_len
;
iov
++;
#define GETIOV(extra_work) \
while (len == 0) { \
extra_work; \
p = iov->iov_base; \
len = iov->iov_len; \
iov++; \
}
if (fp
->_flags
& __SNBF
) {
/*
* Unbuffered: write up to BUFSIZ bytes at a time.
*/
do {
GETIOV
(;);
w
= (*fp
->_write
)(fp
->_cookie
, p
, MIN
(len
, BUFSIZ
));
if (w
<= 0)
goto err
;
p
+= w
;
len
-= w
;
} while ((uio
->uio_resid
-= w
) != 0);
} else if ((fp
->_flags
& __SLBF
) == 0) {
/*
* Fully buffered: fill partially full buffer, if any,
* and then flush. If there is no partial buffer, write
* one _bf._size byte chunk directly (without copying).
*
* String output is a special case: write as many bytes
* as fit, but pretend we wrote everything. This makes
* snprintf() return the number of bytes needed, rather
* than the number used, and avoids its write function
* (so that the write function can be invalid).
*/
do {
GETIOV
(;);
w
= fp
->_w
;
if (fp
->_flags
& __SSTR
) {
if (len
< w
)
w
= len
;
COPY
(w
); /* copy MIN(fp->_w,len), */
fp
->_w
-= w
;
fp
->_p
+= w
;
w
= len
; /* but pretend copied all */
} else if (fp
->_p
> fp
->_bf._base
&& len
> w
) {
/* fill and flush */
COPY
(w
);
/* fp->_w -= w; */ /* unneeded */
fp
->_p
+= w
;
if (fflush(fp
))
goto err
;
} else if (len
>= (w
= fp
->_bf._size
)) {
/* write directly */
w
= (*fp
->_write
)(fp
->_cookie
, p
, w
);
if (w
<= 0)
goto err
;
} else {
/* fill and done */
w
= len
;
COPY
(w
);
fp
->_w
-= w
;
fp
->_p
+= w
;
}
p
+= w
;
len
-= w
;
} while ((uio
->uio_resid
-= w
) != 0);
} else {
/*
* Line buffered: like fully buffered, but we
* must check for newlines. Compute the distance
* to the first newline (including the newline),
* or `infinity' if there is none, then pretend
* that the amount to write is MIN(len,nldist).
*/
nlknown
= 0;
nldist
= 0; /* XXX just to keep gcc happy */
do {
GETIOV
(nlknown
= 0);
if (!nlknown
) {
nl
= memchr((void *)p
, '\n', len
);
nldist
= nl
? nl
+ 1 - p
: len
+ 1;
nlknown
= 1;
}
s
= MIN
(len
, nldist
);
w
= fp
->_w
+ fp
->_bf._size
;
if (fp
->_p
> fp
->_bf._base
&& s
> w
) {
COPY
(w
);
/* fp->_w -= w; */
fp
->_p
+= w
;
if (fflush(fp
))
goto err
;
} else if (s
>= (w
= fp
->_bf._size
)) {
w
= (*fp
->_write
)(fp
->_cookie
, p
, w
);
if (w
<= 0)
goto err
;
} else {
w
= s
;
COPY
(w
);
fp
->_w
-= w
;
fp
->_p
+= w
;
}
if ((nldist
-= w
) == 0) {
/* copied the newline: flush and forget */
if (fflush(fp
))
goto err
;
nlknown
= 0;
}
p
+= w
;
len
-= w
;
} while ((uio
->uio_resid
-= w
) != 0);
}
return (0);
err
:
fp
->_flags
|= __SERR
;
return (EOF
);
}