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Diffstat (limited to 'StdLib/LibC/Stdio/setvbuf.c')
| -rw-r--r-- | StdLib/LibC/Stdio/setvbuf.c | 176 |
1 files changed, 176 insertions, 0 deletions
diff --git a/StdLib/LibC/Stdio/setvbuf.c b/StdLib/LibC/Stdio/setvbuf.c new file mode 100644 index 0000000000..3ea96ff6da --- /dev/null +++ b/StdLib/LibC/Stdio/setvbuf.c @@ -0,0 +1,176 @@ +/** @file
+ Implementation of setvbuf as declared in <stdio.h>.
+
+ Copyright (c) 2010, Intel Corporation. All rights reserved.<BR>
+ This program and the accompanying materials are licensed and made available
+ under the terms and conditions of the BSD License that accompanies this
+ distribution. The full text of the license may be found at
+ http://opensource.org/licenses/bsd-license.php.
+
+ THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+ 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:
+ - Redistributions of source code must retain the above copyright
+ notice, this list of conditions and the following disclaimer.
+ - 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.
+ - 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 COPYRIGHT HOLDERS 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 COPYRIGHT HOLDERS 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.
+
+ NetBSD: setvbuf.c,v 1.17 2003/08/07 16:43:31 agc Exp
+ setvbuf.c 8.2 (Berkeley) 11/16/93
+**/
+#include <LibConfig.h>
+
+#include <assert.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <wchar.h>
+#include "reentrant.h"
+#include "local.h"
+#include <MainData.h>
+
+/*
+ * Set one of the three kinds of buffering, optionally including
+ * a buffer.
+ */
+int
+setvbuf(FILE *fp, char *buf, int mode, size_t size)
+{
+ int ret, flags;
+ size_t iosize;
+ int ttyflag;
+
+ _DIAGASSERT(fp != NULL);
+ /* buf may be NULL */
+
+ /*
+ * Verify arguments. The `int' limit on `size' is due to this
+ * particular implementation. Note, buf and size are ignored
+ * when setting _IONBF.
+ */
+ if (mode != _IONBF)
+ if ((mode != _IOFBF && mode != _IOLBF) || (int)size < 0)
+ return (-1);
+
+ FLOCKFILE(fp);
+ /*
+ * Write current buffer, if any. Discard unread input (including
+ * ungetc data), cancel line buffering, and free old buffer if
+ * malloc()ed. We also clear any eof condition, as if this were
+ * a seek.
+ */
+ ret = 0;
+ (void)__sflush(fp);
+ if (HASUB(fp))
+ FREEUB(fp);
+ WCIO_FREE(fp);
+ fp->_r = fp->_lbfsize = 0;
+ flags = fp->_flags;
+ if (flags & __SMBF)
+ free((void *)fp->_bf._base);
+ flags &= ~(__SLBF | __SNBF | __SMBF | __SOPT | __SNPT | __SEOF);
+
+ /* If setting unbuffered mode, skip all the hard work. */
+ if (mode == _IONBF)
+ goto nbf;
+
+ /*
+ * Find optimal I/O size for seek optimization. This also returns
+ * a `tty flag' to suggest that we check isatty(fd), but we do not
+ * care since our caller told us how to buffer.
+ */
+ flags |= __swhatbuf(fp, &iosize, &ttyflag);
+ if (size == 0) {
+ buf = NULL; /* force local allocation */
+ size = iosize;
+ }
+
+ /* Allocate buffer if needed. */
+ if (buf == NULL) {
+ if ((buf = malloc(size)) == NULL) {
+ /*
+ * Unable to honor user's request. We will return
+ * failure, but try again with file system size.
+ */
+ ret = -1;
+ if (size != iosize) {
+ size = iosize;
+ buf = malloc(size);
+ }
+ }
+ if (buf == NULL) {
+ /* No luck; switch to unbuffered I/O. */
+nbf:
+ fp->_flags = (unsigned short)(flags | __SNBF);
+ fp->_w = 0;
+ fp->_bf._base = fp->_p = fp->_nbuf;
+ fp->_bf._size = 1;
+ FUNLOCKFILE(fp);
+ return (ret);
+ }
+ flags |= __SMBF;
+ }
+
+ /*
+ * Kill any seek optimization if the buffer is not the
+ * right size.
+ *
+ * SHOULD WE ALLOW MULTIPLES HERE (i.e., ok iff (size % iosize) == 0)?
+ */
+ if (size != iosize)
+ flags |= __SNPT;
+
+ /*
+ * Fix up the FILE fields, and set gMD->cleanup for output flush on
+ * exit (since we are buffered in some way).
+ */
+ if (mode == _IOLBF)
+ flags |= __SLBF;
+ fp->_flags = (unsigned short)flags;
+ fp->_bf._base = fp->_p = (unsigned char *)buf;
+ fp->_bf._size = (int)size;
+ /* fp->_lbfsize is still 0 */
+ if (flags & __SWR) {
+ /*
+ * Begin or continue writing: see __swsetup(). Note
+ * that __SNBF is impossible (it was handled earlier).
+ */
+ if (flags & __SLBF) {
+ fp->_w = 0;
+ fp->_lbfsize = -fp->_bf._size;
+ } else
+ fp->_w = (int)size;
+ } else {
+ /* begin/continue reading, or stay in intermediate state */
+ fp->_w = 0;
+ }
+ gMD->cleanup = _cleanup;
+
+ FUNLOCKFILE(fp);
+ return (ret);
+}
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