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-rw-r--r--lib/libc/stdio/fread.c81
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diff --git a/lib/libc/stdio/fread.c b/lib/libc/stdio/fread.c
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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)
+static char sccsid[] = "@(#)fread.c 8.2 (Berkeley) 12/11/93";
+#endif /* LIBC_SCCS and not lint */
+
+#include <stdio.h>
+#include <string.h>
+
+size_t
+fread(buf, size, count, fp)
+ void *buf;
+ size_t size, count;
+ register FILE *fp;
+{
+ register size_t resid;
+ register char *p;
+ register int r;
+ size_t total;
+
+ /*
+ * The ANSI standard requires a return value of 0 for a count
+ * or a size of 0. Peculiarily, it imposes no such requirements
+ * on fwrite; it only requires fread to be broken.
+ */
+ if ((resid = count * size) == 0)
+ return (0);
+ if (fp->_r < 0)
+ fp->_r = 0;
+ total = resid;
+ p = buf;
+ 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 (__srefill(fp)) {
+ /* no more input: return partial result */
+ return ((total - resid) / size);
+ }
+ }
+ (void)memcpy((void *)p, (void *)fp->_p, resid);
+ fp->_r -= resid;
+ fp->_p += resid;
+ return (count);
+}
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