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<a class="el" href="dir_897b6a2d7bab147dd1db58381aad3984.html">src</a> » <a class="el" href="dir_832905b1f7f5feaf61a306b40c0ac817.html">sys</a> » <a class="el" href="dir_d9dcf62a8e8b4cc91cbf2445d76a799b.html">lib</a></div>
<h1>bcopy.c</h1><a href="bcopy_8c.html">Go to the documentation of this file.</a><div class="fragment"><pre class="fragment"><a name="l00001"></a>00001 <span class="comment">/*-</span>
<a name="l00002"></a>00002 <span class="comment"> * Copyright (c) 1990, 1993</span>
<a name="l00003"></a>00003 <span class="comment"> * The Regents of the University of California. All rights reserved.</span>
<a name="l00004"></a>00004 <span class="comment"> *</span>
<a name="l00005"></a>00005 <span class="comment"> * This code is derived from software contributed to Berkeley by</span>
<a name="l00006"></a>00006 <span class="comment"> * Chris Torek.</span>
<a name="l00007"></a>00007 <span class="comment"> *</span>
<a name="l00008"></a>00008 <span class="comment"> * Redistribution and use in source and binary forms, with or without</span>
<a name="l00009"></a>00009 <span class="comment"> * modification, are permitted provided that the following conditions</span>
<a name="l00010"></a>00010 <span class="comment"> * are met:</span>
<a name="l00011"></a>00011 <span class="comment"> * 1. Redistributions of source code must retain the above copyright</span>
<a name="l00012"></a>00012 <span class="comment"> * notice, this list of conditions and the following disclaimer.</span>
<a name="l00013"></a>00013 <span class="comment"> * 2. Redistributions in binary form must reproduce the above copyright</span>
<a name="l00014"></a>00014 <span class="comment"> * notice, this list of conditions and the following disclaimer in the</span>
<a name="l00015"></a>00015 <span class="comment"> * documentation and/or other materials provided with the distribution.</span>
<a name="l00016"></a>00016 <span class="comment"> * 3. All advertising materials mentioning features or use of this software</span>
<a name="l00017"></a>00017 <span class="comment"> * must display the following acknowledgement:</span>
<a name="l00018"></a>00018 <span class="comment"> * This product includes software developed by the University of</span>
<a name="l00019"></a>00019 <span class="comment"> * California, Berkeley and its contributors.</span>
<a name="l00020"></a>00020 <span class="comment"> * 4. Neither the name of the University nor the names of its contributors</span>
<a name="l00021"></a>00021 <span class="comment"> * may be used to endorse or promote products derived from this software</span>
<a name="l00022"></a>00022 <span class="comment"> * without specific prior written permission.</span>
<a name="l00023"></a>00023 <span class="comment"> *</span>
<a name="l00024"></a>00024 <span class="comment"> * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND</span>
<a name="l00025"></a>00025 <span class="comment"> * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE</span>
<a name="l00026"></a>00026 <span class="comment"> * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE</span>
<a name="l00027"></a>00027 <span class="comment"> * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE</span>
<a name="l00028"></a>00028 <span class="comment"> * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL</span>
<a name="l00029"></a>00029 <span class="comment"> * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS</span>
<a name="l00030"></a>00030 <span class="comment"> * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)</span>
<a name="l00031"></a>00031 <span class="comment"> * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT</span>
<a name="l00032"></a>00032 <span class="comment"> * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY</span>
<a name="l00033"></a>00033 <span class="comment"> * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF</span>
<a name="l00034"></a>00034 <span class="comment"> * SUCH DAMAGE.</span>
<a name="l00035"></a>00035 <span class="comment"> *</span>
<a name="l00036"></a>00036 <span class="comment"> * $ID: $</span>
<a name="l00037"></a>00037 <span class="comment"> */</span>
<a name="l00038"></a>00038
<a name="l00039"></a>00039 <span class="preprocessor">#include <<a class="code" href="types_8h.html">ubixos/types.h</a>></span>
<a name="l00040"></a>00040
<a name="l00041"></a>00041 <span class="comment">/*</span>
<a name="l00042"></a>00042 <span class="comment"> * sizeof(word) MUST BE A POWER OF TWO</span>
<a name="l00043"></a>00043 <span class="comment"> * SO THAT wmask BELOW IS ALL ONES</span>
<a name="l00044"></a>00044 <span class="comment"> */</span>
<a name="l00045"></a><a class="code" href="bcopy_8c.html#afc9a69535613ac225df2d6195518116">00045</a> <span class="keyword">typedef</span> <span class="keywordtype">int</span> <a class="code" href="bcopy_8c.html#afc9a69535613ac225df2d6195518116">word</a>; <span class="comment">/* "word" used for optimal copy speed */</span>
<a name="l00046"></a><a class="code" href="bcopy_8c.html#e8e8d04e2eddef3a5f57fe2f28c655fa">00046</a> <span class="keyword">typedef</span> <a class="code" href="types_8h.html#ba29fd78d95cce0ecb249c24b58d07da">u_int32_t</a> <a class="code" href="bcopy_8c.html#e8e8d04e2eddef3a5f57fe2f28c655fa">uintptr_t</a>;
<a name="l00047"></a>00047
<a name="l00048"></a><a class="code" href="bcopy_8c.html#01c6b59ca21f041b23efbb9845cc4e32">00048</a> <span class="preprocessor">#define wsize sizeof(word)</span>
<a name="l00049"></a><a class="code" href="bcopy_8c.html#b5deaef115ff5ca6ef1457d923d8331a">00049</a> <span class="preprocessor"></span><span class="preprocessor">#define wmask (wsize - 1)</span>
<a name="l00050"></a>00050 <span class="preprocessor"></span>
<a name="l00051"></a>00051 <span class="comment">/*</span>
<a name="l00052"></a>00052 <span class="comment"> * Copy a block of memory, handling overlap.</span>
<a name="l00053"></a>00053 <span class="comment"> * This is the routine that actually implements</span>
<a name="l00054"></a>00054 <span class="comment"> * (the portable versions of) bcopy, memcpy, and memmove.</span>
<a name="l00055"></a>00055 <span class="comment"> */</span>
<a name="l00056"></a>00056 <span class="preprocessor">#if defined(MEMCOPY) || defined(MEMMOVE)</span>
<a name="l00057"></a>00057 <span class="preprocessor"></span><span class="preprocessor">#include <<a class="code" href="string_8h.html">string.h</a>></span>
<a name="l00058"></a>00058
<a name="l00059"></a>00059 <span class="keywordtype">void</span> *
<a name="l00060"></a>00060 <span class="preprocessor">#ifdef MEMCOPY</span>
<a name="l00061"></a>00061 <span class="preprocessor"></span><a class="code" href="lib_2string_8h.html#e33b18edb618c656b9b795b9fce2316c">memcpy</a>
<a name="l00062"></a>00062 <span class="preprocessor">#else</span>
<a name="l00063"></a>00063 <span class="preprocessor"></span>memmove
<a name="l00064"></a>00064 <span class="preprocessor">#endif</span>
<a name="l00065"></a>00065 <span class="preprocessor"></span>(<span class="keywordtype">void</span> *dst0, <span class="keyword">const</span> <span class="keywordtype">void</span> *src0, <a class="code" href="types_8h.html#7619b847aeded8a6d14cbfa212b2cdfb">size_t</a> length)
<a name="l00066"></a>00066 #<span class="keywordflow">else</span>
<a name="l00067"></a>00067 #include <strings.h>
<a name="l00068"></a>00068
<a name="l00069"></a>00069 <span class="keywordtype">void</span>
<a name="l00070"></a><a class="code" href="bcopy_8c.html#7d2165a6aaf8577fe615ccf03eba693d">00070</a> <a class="code" href="bcopy_8c.html#7d2165a6aaf8577fe615ccf03eba693d">bcopy</a>(<span class="keyword">const</span> <span class="keywordtype">void</span> *src0, <span class="keywordtype">void</span> *dst0, <a class="code" href="types_8h.html#7619b847aeded8a6d14cbfa212b2cdfb">size_t</a> length)
<a name="l00071"></a>00071 <span class="preprocessor">#endif</span>
<a name="l00072"></a>00072 <span class="preprocessor"></span>{
<a name="l00073"></a>00073 <span class="keywordtype">char</span> *dst = dst0;
<a name="l00074"></a>00074 <span class="keyword">const</span> <span class="keywordtype">char</span> *src = src0;
<a name="l00075"></a>00075 <a class="code" href="types_8h.html#7619b847aeded8a6d14cbfa212b2cdfb">size_t</a> t;
<a name="l00076"></a>00076
<a name="l00077"></a>00077 <span class="keywordflow">if</span> (length == 0 || dst == src) <span class="comment">/* nothing to do */</span>
<a name="l00078"></a>00078 <span class="keywordflow">goto</span> <a class="code" href="fdc_8c.html#3041fe08ed5976302158f2668249f8b2">done</a>;
<a name="l00079"></a>00079
<a name="l00080"></a>00080 <span class="comment">/*</span>
<a name="l00081"></a>00081 <span class="comment"> * Macros: loop-t-times; and loop-t-times, t>0</span>
<a name="l00082"></a>00082 <span class="comment"> */</span>
<a name="l00083"></a>00083 <span class="preprocessor">#define TLOOP(s) if (t) TLOOP1(s)</span>
<a name="l00084"></a>00084 <span class="preprocessor"></span><span class="preprocessor">#define TLOOP1(s) do { s; } while (--t)</span>
<a name="l00085"></a>00085 <span class="preprocessor"></span>
<a name="l00086"></a>00086 <span class="keywordflow">if</span> ((<span class="keywordtype">unsigned</span> <span class="keywordtype">long</span>)dst < (<span class="keywordtype">unsigned</span> <span class="keywordtype">long</span>)src) {
<a name="l00087"></a>00087 <span class="comment">/*</span>
<a name="l00088"></a>00088 <span class="comment"> * Copy forward.</span>
<a name="l00089"></a>00089 <span class="comment"> */</span>
<a name="l00090"></a>00090 t = (<a class="code" href="bcopy_8c.html#e8e8d04e2eddef3a5f57fe2f28c655fa">uintptr_t</a>)src; <span class="comment">/* only need low bits */</span>
<a name="l00091"></a>00091 <span class="keywordflow">if</span> ((t | (<a class="code" href="bcopy_8c.html#e8e8d04e2eddef3a5f57fe2f28c655fa">uintptr_t</a>)dst) & <a class="code" href="bcopy_8c.html#b5deaef115ff5ca6ef1457d923d8331a">wmask</a>) {
<a name="l00092"></a>00092 <span class="comment">/*</span>
<a name="l00093"></a>00093 <span class="comment"> * Try to align operands. This cannot be done</span>
<a name="l00094"></a>00094 <span class="comment"> * unless the low bits match.</span>
<a name="l00095"></a>00095 <span class="comment"> */</span>
<a name="l00096"></a>00096 <span class="keywordflow">if</span> ((t ^ (<a class="code" href="bcopy_8c.html#e8e8d04e2eddef3a5f57fe2f28c655fa">uintptr_t</a>)dst) & wmask || length < <a class="code" href="bcopy_8c.html#01c6b59ca21f041b23efbb9845cc4e32">wsize</a>)
<a name="l00097"></a>00097 t = length;
<a name="l00098"></a>00098 <span class="keywordflow">else</span>
<a name="l00099"></a>00099 t = <a class="code" href="bcopy_8c.html#01c6b59ca21f041b23efbb9845cc4e32">wsize</a> - (t & wmask);
<a name="l00100"></a>00100 length -= t;
<a name="l00101"></a>00101 <a class="code" href="bcopy_8c.html#4d81791363bd2fd7e37c9a533be06f59">TLOOP1</a>(*dst++ = *src++);
<a name="l00102"></a>00102 }
<a name="l00103"></a>00103 <span class="comment">/*</span>
<a name="l00104"></a>00104 <span class="comment"> * Copy whole words, then mop up any trailing bytes.</span>
<a name="l00105"></a>00105 <span class="comment"> */</span>
<a name="l00106"></a>00106 t = length / <a class="code" href="bcopy_8c.html#01c6b59ca21f041b23efbb9845cc4e32">wsize</a>;
<a name="l00107"></a>00107 <a class="code" href="bcopy_8c.html#74d8274a661a711f2c9e05a7f19eaf0f">TLOOP</a>(*(<a class="code" href="bcopy_8c.html#afc9a69535613ac225df2d6195518116">word</a> *)dst = *(<a class="code" href="bcopy_8c.html#afc9a69535613ac225df2d6195518116">word</a> *)src; src += <a class="code" href="bcopy_8c.html#01c6b59ca21f041b23efbb9845cc4e32">wsize</a>; dst += <a class="code" href="bcopy_8c.html#01c6b59ca21f041b23efbb9845cc4e32">wsize</a>);
<a name="l00108"></a>00108 t = length & wmask;
<a name="l00109"></a>00109 <a class="code" href="bcopy_8c.html#74d8274a661a711f2c9e05a7f19eaf0f">TLOOP</a>(*dst++ = *src++);
<a name="l00110"></a>00110 } <span class="keywordflow">else</span> {
<a name="l00111"></a>00111 <span class="comment">/*</span>
<a name="l00112"></a>00112 <span class="comment"> * Copy backwards. Otherwise essentially the same.</span>
<a name="l00113"></a>00113 <span class="comment"> * Alignment works as before, except that it takes</span>
<a name="l00114"></a>00114 <span class="comment"> * (t&wmask) bytes to align, not wsize-(t&wmask).</span>
<a name="l00115"></a>00115 <span class="comment"> */</span>
<a name="l00116"></a>00116 src += length;
<a name="l00117"></a>00117 dst += length;
<a name="l00118"></a>00118 t = (<a class="code" href="bcopy_8c.html#e8e8d04e2eddef3a5f57fe2f28c655fa">uintptr_t</a>)src;
<a name="l00119"></a>00119 <span class="keywordflow">if</span> ((t | (<a class="code" href="bcopy_8c.html#e8e8d04e2eddef3a5f57fe2f28c655fa">uintptr_t</a>)dst) & <a class="code" href="bcopy_8c.html#b5deaef115ff5ca6ef1457d923d8331a">wmask</a>) {
<a name="l00120"></a>00120 <span class="keywordflow">if</span> ((t ^ (<a class="code" href="bcopy_8c.html#e8e8d04e2eddef3a5f57fe2f28c655fa">uintptr_t</a>)dst) & wmask || length <= <a class="code" href="bcopy_8c.html#01c6b59ca21f041b23efbb9845cc4e32">wsize</a>)
<a name="l00121"></a>00121 t = length;
<a name="l00122"></a>00122 <span class="keywordflow">else</span>
<a name="l00123"></a>00123 t &= wmask;
<a name="l00124"></a>00124 length -= t;
<a name="l00125"></a>00125 <a class="code" href="bcopy_8c.html#4d81791363bd2fd7e37c9a533be06f59">TLOOP1</a>(*--dst = *--src);
<a name="l00126"></a>00126 }
<a name="l00127"></a>00127 t = length / <a class="code" href="bcopy_8c.html#01c6b59ca21f041b23efbb9845cc4e32">wsize</a>;
<a name="l00128"></a>00128 <a class="code" href="bcopy_8c.html#74d8274a661a711f2c9e05a7f19eaf0f">TLOOP</a>(src -= <a class="code" href="bcopy_8c.html#01c6b59ca21f041b23efbb9845cc4e32">wsize</a>; dst -= <a class="code" href="bcopy_8c.html#01c6b59ca21f041b23efbb9845cc4e32">wsize</a>; *(<a class="code" href="bcopy_8c.html#afc9a69535613ac225df2d6195518116">word</a> *)dst = *(<a class="code" href="bcopy_8c.html#afc9a69535613ac225df2d6195518116">word</a> *)src);
<a name="l00129"></a>00129 t = length & wmask;
<a name="l00130"></a>00130 <a class="code" href="bcopy_8c.html#74d8274a661a711f2c9e05a7f19eaf0f">TLOOP</a>(*--dst = *--src);
<a name="l00131"></a>00131 }
<a name="l00132"></a>00132 <a class="code" href="fdc_8c.html#3041fe08ed5976302158f2668249f8b2">done</a>:
<a name="l00133"></a>00133 <span class="preprocessor">#if defined(MEMCOPY) || defined(MEMMOVE)</span>
<a name="l00134"></a>00134 <span class="preprocessor"></span> <span class="keywordflow">return</span> (dst0);
<a name="l00135"></a>00135 <span class="preprocessor">#else</span>
<a name="l00136"></a>00136 <span class="preprocessor"></span> <span class="keywordflow">return</span>;
<a name="l00137"></a>00137 <span class="preprocessor">#endif</span>
<a name="l00138"></a>00138 <span class="preprocessor"></span>}
</pre></div><hr size="1"><address style="align: right;"><small>Generated on Fri Dec 15 11:18:55 2006 for UbixOS V2 by
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