1 #if defined(__sun) && !defined(__SVR4)
2 /*-
3  * Copyright (c) 1990, 1993
4  *  The Regents of the University of California.  All rights reserved.
5  *
6  * This code is derived from software contributed to Berkeley by
7  * Chris Torek.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. ***REMOVED*** - see
18  *    ftp://ftp.cs.berkeley.edu/pub/4bsd/README.Impt.License.Change
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #if defined(LIBC_SCCS) && !defined(lint)
37 static char sccsid[] = "@(#)bcopy.c 8.1 (Berkeley) 6/4/93";
38 #endif /* LIBC_SCCS and not lint */
39 
40 #include <string.h>
41 
42 /*
43  * sizeof(word) MUST BE A POWER OF TWO
44  * SO THAT wmask BELOW IS ALL ONES
45  */
46 typedef int word; /* "word" used for optimal copy speed */
47 
48 #define wsize sizeof(word)
49 #define wmask (wsize - 1)
50 
51 /*
52  * Copy a block of memory, handling overlap.
53  * This is the routine that actually implements
54  * (the portable versions of) bcopy, memcpy, and memmove.
55  */
56 #ifdef MEMCOPY
57 void *
memcpy(dst0,src0,length)58     memcpy(dst0, src0, length)
59 #else
60 #ifdef MEMMOVE
61 void *
62     memmove(dst0, src0, length)
63 #else
64 void
65     bcopy(src0, dst0, length)
66 #endif
67 #endif
68         void *dst0;
69 const void *src0;
70 register size_t length;
71 {
72     register char *dst = dst0;
73     register const char *src = src0;
74     register size_t t;
75 
76     if (length == 0 || dst == src) /* nothing to do */
77         goto done;
78 
79 /*
80      * Macros: loop-t-times; and loop-t-times, t>0
81      */
82 #define TLOOP(s) \
83     if (t)       \
84     TLOOP1(s)
85 #define TLOOP1(s) \
86     do {          \
87         s;        \
88     } while (--t)
89 
90     if ((unsigned long)dst < (unsigned long)src) {
91         /*
92          * Copy forward.
93          */
94         t = (int)src; /* only need low bits */
95         if ((t | (int)dst) & wmask) {
96             /*
97              * Try to align operands.  This cannot be done
98              * unless the low bits match.
99              */
100             if ((t ^ (int)dst) & wmask || length < wsize)
101                 t = length;
102             else
103                 t = wsize - (t & wmask);
104             length -= t;
105             TLOOP1(*dst++ = *src++);
106         }
107         /*
108          * Copy whole words, then mop up any trailing bytes.
109          */
110         t = length / wsize;
111         TLOOP(*(word *)dst = *(word *)src; src += wsize; dst += wsize);
112         t = length & wmask;
113         TLOOP(*dst++ = *src++);
114     } else {
115         /*
116          * Copy backwards.  Otherwise essentially the same.
117          * Alignment works as before, except that it takes
118          * (t&wmask) bytes to align, not wsize-(t&wmask).
119          */
120         src += length;
121         dst += length;
122         t = (int)src;
123         if ((t | (int)dst) & wmask) {
124             if ((t ^ (int)dst) & wmask || length <= wsize)
125                 t = length;
126             else
127                 t &= wmask;
128             length -= t;
129             TLOOP1(*--dst = *--src);
130         }
131         t = length / wsize;
132         TLOOP(src -= wsize; dst -= wsize; *(word *)dst = *(word *)src);
133         t = length & wmask;
134         TLOOP(*--dst = *--src);
135     }
136 done:
137 #if defined(MEMCOPY) || defined(MEMMOVE)
138     return (dst0);
139 #else
140     return;
141 #endif
142 }
143 #endif /* no __sgi */
144 
145 /* Some compilers don't like an empty source file. */
146 static int dummy = 0;
147