BSD 4_3_Net_2 release

[unix-history] / usr / src / lib / libc / stdio / fread.c

diff --git a/usr/src/lib/libc/stdio/fread.c b/usr/src/lib/libc/stdio/fread.c
index b78d7d0..affdef9 100644 (file)
--- a/usr/src/lib/libc/stdio/fread.c
+++ b/usr/src/lib/libc/stdio/fread.c
@@ -1,46 +1,75 @@
-/*
- * Copyright (c) 1980 Regents of the University of California.
- * All rights reserved.  The Berkeley software License Agreement
- * specifies the terms and conditions for redistribution.
+/*-
+ * Copyright (c) 1990 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 defined(LIBC_SCCS) && !defined(lint)

-static char sccsid[] = "@(#)fread.c    5.2 (Berkeley) 3/9/86";
-#endif LIBC_SCCS and not lint
+static char sccsid[] = "@(#)fread.c    5.4 (Berkeley) 5/4/91";
+#endif /* LIBC_SCCS and not lint */

 
 

-#include       <stdio.h>
+#include <stdio.h>
+#include <string.h>

 
 

-fread(ptr, size, count, iop)
-       register char *ptr;
-       unsigned size, count;
-       register FILE *iop;
+fread(buf, size, count, fp)
+       void *buf;
+       size_t size, count;
+       register FILE *fp;

 {
 {

-       register int s;
-       int c;
+       register size_t resid;
+       register char *p;
+       register int r;
+       size_t total;

 
 

-       s = size * count;
-       while (s > 0) {
-               if (iop->_cnt < s) {
-                       if (iop->_cnt > 0) {
-                               bcopy(iop->_ptr, ptr, iop->_cnt);
-                               ptr += iop->_cnt;
-                               s -= iop->_cnt;
-                       }
-                       /*
-                        * filbuf clobbers _cnt & _ptr,
-                        * so don't waste time setting them.
-                        */
-                       if ((c = _filbuf(iop)) == EOF)
-                               break;
-                       *ptr++ = c;
-                       s--;
-               }
-               if (iop->_cnt >= s) {
-                       bcopy(iop->_ptr, ptr, s);
-                       iop->_ptr += s;
-                       iop->_cnt -= s;
-                       return (count);
+       if ((resid = count * size) == 0)
+               return (count);
+       if (fp->_r < 0)
+               fp->_r = 0;
+       total = resid;
+       p = buf;
+       while (resid > (r = fp->_r)) {
+               (void) bcopy((void *)fp->_p, (void *)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);

                }
        }
                }
        }

-       return (size != 0 ? count - ((s + size - 1) / size) : 0);
+       (void) bcopy((void *)fp->_p, (void *)p, resid);
+       fp->_r -= resid;
+       fp->_p += resid;
+       return (count);

 }
 }