Author: pfg
Date: Sun Jul 20 20:05:39 2014
New Revision: 268924
URL: http://svnweb.freebsd.org/changeset/base/268924
Log:
Update fflush(3) to return success on a read-only stream.
This has small changes to what Apple uses for compliance
with SUSv3. The changes cause no secondary effects in the
gnulib tests (we pass them).
Obtained from: Apple Inc. (Libc 997.90.3 with changes)
Reviewed by: bde
Phabric: D440
Modified:
head/lib/libc/stdio/fflush.c
Modified: head/lib/libc/stdio/fflush.c
==============================================================================
--- head/lib/libc/stdio/fflush.c Sun Jul 20 18:44:56 2014
(r268923)
+++ head/lib/libc/stdio/fflush.c Sun Jul 20 20:05:39 2014
(r268924)
@@ -60,7 +60,7 @@ fflush(FILE *fp)
/*
* There is disagreement about the correct behaviour of fflush()
- * when passed a file which is not open for reading. According to
+ * when passed a file which is not open for writing. According to
* the ISO C standard, the behaviour is undefined.
* Under linux, such an fflush returns success and has no effect;
* under Windows, such an fflush is documented as behaving instead
@@ -68,11 +68,13 @@ fflush(FILE *fp)
* Given that applications may be written with the expectation of
* either of these two behaviours, the only safe (non-astonishing)
* option is to return EBADF and ask that applications be fixed.
+ * SUSv3 now requires that fflush() returns success on a read-only
+ * stream.
+ *
*/
- if ((fp->_flags & (__SWR | __SRW)) == 0) {
- errno = EBADF;
- retval = EOF;
- } else
+ if ((fp->_flags & (__SWR | __SRW)) == 0)
+ retval = 0;
+ else
retval = __sflush(fp);
FUNLOCKFILE(fp);
return (retval);
@@ -89,10 +91,9 @@ __fflush(FILE *fp)
if (fp == NULL)
return (_fwalk(sflush_locked));
- if ((fp->_flags & (__SWR | __SRW)) == 0) {
- errno = EBADF;
- retval = EOF;
- } else
+ if ((fp->_flags & (__SWR | __SRW)) == 0)
+ retval = 0;
+ else
retval = __sflush(fp);
return (retval);
}
@@ -122,6 +123,12 @@ __sflush(FILE *fp)
for (; n > 0; n -= t, p += t) {
t = _swrite(fp, (char *)p, n);
if (t <= 0) {
+ /* Reset _p and _w. */
+ if (p > fp->_p) /* Some was written. */
+ memmove(fp->_p, p, n);
+ fp->_p += n;
+ if ((fp->_flags & (__SLBF | __SNBF)) == 0)
+ fp->_w -= n;
fp->_flags |= __SERR;
return (EOF);
}
_______________________________________________
svn-src-head@freebsd.org mailing list
http://lists.freebsd.org/mailman/listinfo/svn-src-head
To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
