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stdio/FreeBSD/fread.c /dev/null Libc-1583.40.7
--- /dev/null
+++ Libc/Libc-1583.40.7/stdio/FreeBSD/fread.c
@@ -0,0 +1,166 @@
+/*-
+ * 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.
+ * 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)
+static char sccsid[] = "@(#)fread.c	8.2 (Berkeley) 12/11/93";
+#endif /* LIBC_SCCS and not lint */
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD: src/lib/libc/stdio/fread.c,v 1.16 2009/07/12 13:09:43 ed Exp $");
+
+#include "namespace.h"
+#include <stdio.h>
+#include <string.h>
+#include "un-namespace.h"
+#include "local.h"
+#include "libc_private.h"
+
+/*
+ * MT-safe version
+ */
+
+size_t
+fread(void * __restrict buf, size_t size, size_t count, FILE * __restrict fp)
+{
+	size_t ret;
+
+	FLOCKFILE(fp);
+	ret = __fread(buf, size, count, fp);
+	FUNLOCKFILE(fp);
+	return (ret);
+}
+
+/*
+ * The maximum amount to read to avoid integer overflow.  INT_MAX is odd,
+ * so it make sense to make it even.  We subtract (BUFSIZ - 1) to get a
+ * whole number of BUFSIZ chunks.
+ */
+#define MAXREAD	(INT_MAX - (BUFSIZ - 1))
+
+/* __fread0: int sized, with size = 1 */
+static inline int
+__fread0(void * __restrict buf, int count, FILE * __restrict fp)
+{
+	int resid;
+	char *p;
+	int r, ret;
+
+	resid = count;
+	p = buf;
+	/* first deal with anything left in buffer, plus any ungetc buffers */
+	while (resid > (r = fp->_r)) {
+		(void)memcpy((void *)p, (void *)fp->_p, (size_t)r);
+		fp->_p += r;
+		/* fp->_r = 0 ... done in __srefill */
+		p += r;
+		resid -= r;
+		if ((ret = __srefill0(fp)) > 0)
+			break;
+		else if (ret) {
+			/* no more input: return partial result */
+			return (count - resid);
+		}
+	}
+	/*
+	 * 5980080: don't use optimization if __SMBF not set (meaning setvbuf
+	 * was called, and the buffer belongs to the user).
+	 * 6180417: but for unbuffered (__SMBF is not set), so specifically
+	 * test for it.
+	 */
+	if ((fp->_flags & (__SMBF | __SNBF)) && resid > fp->_bf._size) {
+		struct __sbuf save;
+		size_t n;
+
+		save = fp->_bf;
+		fp->_bf._base = (unsigned char *)p;
+		fp->_bf._size = resid;
+		while (fp->_bf._size > 0) {
+			if ((ret = __srefill1(fp)) != 0) {
+				/* no more input: return partial result */
+				resid = fp->_bf._size;
+				fp->_bf = save;
+				fp->_p = fp->_bf._base;
+				/* fp->_r = 0;  already set in __srefill1 */
+				return (count - resid);
+			}
+			fp->_bf._base += fp->_r;
+			fp->_bf._size -= fp->_r;
+		}
+		fp->_bf = save;
+		n = fp->_bf._size * ((resid - 1) / fp->_bf._size);
+		r = resid - n;
+		(void)memcpy((void *)fp->_bf._base, (void *)(p + n), (size_t)r);
+		fp->_p = fp->_bf._base + r;
+		fp->_r = 0;
+	} else {
+		while (resid > (r = fp->_r)) {
+			(void)memcpy((void *)p, (void *)fp->_p, (size_t)r);
+			fp->_p += r;
+			/* fp->_r = 0 ... done in __srefill */
+			p += r;
+			resid -= r;
+			if (__srefill1(fp)) {
+				/* no more input: return partial result */
+				return (count - resid);
+			}
+		}
+		(void)memcpy((void *)p, (void *)fp->_p, resid);
+		fp->_r -= resid;
+		fp->_p += resid;
+	}
+	return (count);
+}
+
+size_t
+__fread(void * __restrict buf, size_t size, size_t count, FILE * __restrict fp)
+{
+	size_t resid;
+	int r, ret;
+	size_t total;
+
+	/*
+	 * ANSI and SUSv2 require a return value of 0 if size or count are 0.
+	 */
+	if ((resid = count * size) == 0)
+		return (0);
+	ORIENT(fp, -1);
+	if (fp->_r < 0)
+		fp->_r = 0;
+
+	for (total = resid; resid > 0; buf += r, resid -= r) {
+		r = resid > INT_MAX ? MAXREAD : (int)resid;
+		if ((ret = __fread0(buf, r, fp)) != r) {
+			count = (total - resid + ret) / size;
+			break;
+		}
+	}
+	return (count);
+}