71803c8c1b9b6ca9ea293382ddead557adb8bbd1
[m6w6/libmemcached] / libmemcached / memcached_generate_hash_value.html
1
2
3 <!DOCTYPE html>
4 <!--[if IE 8]><html class="no-js lt-ie9" lang="en" > <![endif]-->
5 <!--[if gt IE 8]><!--> <html class="no-js" lang="en" > <!--<![endif]-->
6 <head>
7 <meta charset="utf-8">
8
9 <meta name="viewport" content="width=device-width, initial-scale=1.0">
10
11 <title>Generating hash values directly &mdash; libmemcached 1.0.99 documentation</title>
12
13
14
15
16
17
18
19
20 <script type="text/javascript" src="../_static/js/modernizr.min.js"></script>
21
22
23 <script type="text/javascript" id="documentation_options" data-url_root="../" src="../_static/documentation_options.js"></script>
24 <script src="../_static/jquery.js"></script>
25 <script src="../_static/underscore.js"></script>
26 <script src="../_static/doctools.js"></script>
27 <script src="../_static/language_data.js"></script>
28
29 <script type="text/javascript" src="../_static/js/theme.js"></script>
30
31
32
33
34 <link rel="stylesheet" href="../_static/css/theme.css" type="text/css" />
35 <link rel="stylesheet" href="../_static/pygments.css" type="text/css" />
36 <link rel="index" title="Index" href="../genindex.html" />
37 <link rel="search" title="Search" href="../search.html" />
38 <link rel="copyright" title="Copyright" href="../copyright.html" />
39 <link rel="next" title="SASL support" href="memcached_sasl.html" />
40 <link rel="prev" title="Set encryption key" href="memcached_set_encoding_key.html" />
41 </head>
42
43 <body class="wy-body-for-nav">
44
45
46 <div class="wy-grid-for-nav">
47
48 <nav data-toggle="wy-nav-shift" class="wy-nav-side">
49 <div class="wy-side-scroll">
50 <div class="wy-side-nav-search" >
51
52
53
54 <a href="../index.html" class="icon icon-home"> libmemcached
55
56
57
58 </a>
59
60
61
62
63 <div class="version">
64 1.0
65 </div>
66
67
68
69
70 <div role="search">
71 <form id="rtd-search-form" class="wy-form" action="../search.html" method="get">
72 <input type="text" name="q" placeholder="Search docs" />
73 <input type="hidden" name="check_keywords" value="yes" />
74 <input type="hidden" name="area" value="default" />
75 </form>
76 </div>
77
78
79 </div>
80
81 <div class="wy-menu wy-menu-vertical" data-spy="affix" role="navigation" aria-label="main navigation">
82
83
84
85
86
87
88 <p class="caption"><span class="caption-text">libmemcached</span></p>
89 <ul class="current">
90 <li class="toctree-l1"><a class="reference internal" href="../libmemcached.html">Introduction</a></li>
91 <li class="toctree-l1 current"><a class="reference internal" href="index.html">libmemcached API</a><ul class="current">
92 <li class="toctree-l2"><a class="reference internal" href="index_basics.html">Basics</a></li>
93 <li class="toctree-l2"><a class="reference internal" href="index_data.html">Working with Data</a></li>
94 <li class="toctree-l2"><a class="reference internal" href="index_errors.html">Messages and Errors</a></li>
95 <li class="toctree-l2 current"><a class="reference internal" href="index_advanced.html">Advanced Topics</a><ul class="current">
96 <li class="toctree-l3"><a class="reference internal" href="index_advanced_internals.html">Internal Behavior</a></li>
97 <li class="toctree-l3 current"><a class="reference internal" href="index_advanced_aeh.html">Authentication, Encryption &amp; Hashing</a><ul class="current">
98 <li class="toctree-l4"><a class="reference internal" href="memcached_set_encoding_key.html">Set encryption key</a></li>
99 <li class="toctree-l4 current"><a class="current reference internal" href="#">Generating hash values directly</a></li>
100 <li class="toctree-l4"><a class="reference internal" href="memcached_sasl.html">SASL support</a></li>
101 </ul>
102 </li>
103 <li class="toctree-l3"><a class="reference internal" href="index_advanced_servers.html">Servers and Server Lists</a></li>
104 <li class="toctree-l3"><a class="reference internal" href="index_advanced_daemon.html">Affecting the memcached Daemon</a></li>
105 <li class="toctree-l3"><a class="reference internal" href="index_advanced_stats.html">Statistics</a></li>
106 </ul>
107 </li>
108 <li class="toctree-l2"><a class="reference internal" href="index_deprecated.html">Deprecated Functionality</a></li>
109 </ul>
110 </li>
111 <li class="toctree-l1"><a class="reference internal" href="index_misc.html">Misc</a></li>
112 </ul>
113 <p class="caption"><span class="caption-text">libmemcachedutil</span></p>
114 <ul>
115 <li class="toctree-l1"><a class="reference internal" href="../libmemcachedutil.html">Introduction</a></li>
116 <li class="toctree-l1"><a class="reference internal" href="../libmemcachedutil/index.html">libmemcachedutil API</a></li>
117 </ul>
118 <p class="caption"><span class="caption-text">libhashkit</span></p>
119 <ul>
120 <li class="toctree-l1"><a class="reference internal" href="../libhashkit.html">Introduction</a></li>
121 <li class="toctree-l1"><a class="reference internal" href="../libhashkit/index.html">libhashkit API</a></li>
122 </ul>
123 <p class="caption"><span class="caption-text">Client Applications</span></p>
124 <ul>
125 <li class="toctree-l1"><a class="reference internal" href="../bin/index.html">Client Applications</a></li>
126 </ul>
127 <p class="caption"><span class="caption-text">Copyright</span></p>
128 <ul>
129 <li class="toctree-l1"><a class="reference internal" href="../copyright.html">Copyright</a></li>
130 </ul>
131
132
133
134 </div>
135 </div>
136 </nav>
137
138 <section data-toggle="wy-nav-shift" class="wy-nav-content-wrap">
139
140
141 <nav class="wy-nav-top" aria-label="top navigation">
142
143 <i data-toggle="wy-nav-top" class="fa fa-bars"></i>
144 <a href="../index.html">libmemcached</a>
145
146 </nav>
147
148
149 <div class="wy-nav-content">
150
151 <div class="rst-content">
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169 <div role="navigation" aria-label="breadcrumbs navigation">
170
171 <ul class="wy-breadcrumbs">
172
173 <li><a href="../index.html">Docs</a> &raquo;</li>
174
175 <li><a href="index.html">libmemcached API</a> &raquo;</li>
176
177 <li><a href="index_advanced.html">Advanced Topics</a> &raquo;</li>
178
179 <li><a href="index_advanced_aeh.html">Authentication, Encryption &amp; Hashing</a> &raquo;</li>
180
181 <li>Generating hash values directly</li>
182
183
184 <li class="wy-breadcrumbs-aside">
185
186
187
188 </li>
189
190 </ul>
191
192
193 <hr/>
194 </div>
195 <div role="main" class="document" itemscope="itemscope" itemtype="http://schema.org/Article">
196 <div itemprop="articleBody">
197
198 <div class="section" id="generating-hash-values-directly">
199 <h1>Generating hash values directly<a class="headerlink" href="#generating-hash-values-directly" title="Permalink to this headline"></a></h1>
200 <p id="index-0">Hash a key value</p>
201 <div class="section" id="synopsis">
202 <h2>SYNOPSIS<a class="headerlink" href="#synopsis" title="Permalink to this headline"></a></h2>
203 <p>#include &lt;libmemcached/memcached.h&gt;</p>
204 <dl class="cpp type">
205 <dt id="_CPPv416memcached_hash_t">
206 <span id="_CPPv316memcached_hash_t"></span><span id="_CPPv216memcached_hash_t"></span><span id="memcached_hash_t"></span><em class="property">type </em><code class="sig-name descname">memcached_hash_t</code><a class="headerlink" href="#_CPPv416memcached_hash_t" title="Permalink to this definition"></a><br /></dt>
207 <dd></dd></dl>
208
209 <dl class="cpp function">
210 <dt id="_CPPv429memcached_generate_hash_valuePKc6size_t16memcached_hash_t">
211 <span id="_CPPv329memcached_generate_hash_valuePKc6size_t16memcached_hash_t"></span><span id="_CPPv229memcached_generate_hash_valuePKc6size_t16memcached_hash_t"></span><span id="memcached_generate_hash_value__cCP.s.memcached_hash_t"></span>uint32_t <code class="sig-name descname">memcached_generate_hash_value</code><span class="sig-paren">(</span><em class="property">const</em> char *<em>key</em>, size_t <em>key_length</em>, <a class="reference internal" href="#_CPPv416memcached_hash_t" title="memcached_hash_t">memcached_hash_t</a> <em>hash_algorithm</em><span class="sig-paren">)</span><a class="headerlink" href="#_CPPv429memcached_generate_hash_valuePKc6size_t16memcached_hash_t" title="Permalink to this definition"></a><br /></dt>
212 <dd></dd></dl>
213
214 <dl class="cpp function">
215 <dt id="_CPPv423memcached_generate_hashP12memcached_stPKc6size_t">
216 <span id="_CPPv323memcached_generate_hashP12memcached_stPKc6size_t"></span><span id="_CPPv223memcached_generate_hashP12memcached_stPKc6size_t"></span><span id="memcached_generate_hash__memcached_stP.cCP.s"></span>uint32_t <code class="sig-name descname">memcached_generate_hash</code><span class="sig-paren">(</span><a class="reference internal" href="memcached_create.html#_CPPv412memcached_st" title="memcached_st">memcached_st</a> *<em>ptr</em>, <em class="property">const</em> char *<em>key</em>, size_t <em>key_length</em><span class="sig-paren">)</span><a class="headerlink" href="#_CPPv423memcached_generate_hashP12memcached_stPKc6size_t" title="Permalink to this definition"></a><br /></dt>
217 <dd></dd></dl>
218
219 <dl class="cpp type">
220 <dt id="_CPPv422MEMCACHED_HASH_DEFAULT">
221 <span id="_CPPv322MEMCACHED_HASH_DEFAULT"></span><span id="_CPPv222MEMCACHED_HASH_DEFAULT"></span><span id="MEMCACHED_HASH_DEFAULT"></span><em class="property">type </em><code class="sig-name descname">MEMCACHED_HASH_DEFAULT</code><a class="headerlink" href="#_CPPv422MEMCACHED_HASH_DEFAULT" title="Permalink to this definition"></a><br /></dt>
222 <dd></dd></dl>
223
224 <dl class="cpp type">
225 <dt id="_CPPv418MEMCACHED_HASH_MD5">
226 <span id="_CPPv318MEMCACHED_HASH_MD5"></span><span id="_CPPv218MEMCACHED_HASH_MD5"></span><span id="MEMCACHED_HASH_MD5"></span><em class="property">type </em><code class="sig-name descname">MEMCACHED_HASH_MD5</code><a class="headerlink" href="#_CPPv418MEMCACHED_HASH_MD5" title="Permalink to this definition"></a><br /></dt>
227 <dd></dd></dl>
228
229 <dl class="cpp type">
230 <dt id="_CPPv418MEMCACHED_HASH_CRC">
231 <span id="_CPPv318MEMCACHED_HASH_CRC"></span><span id="_CPPv218MEMCACHED_HASH_CRC"></span><span id="MEMCACHED_HASH_CRC"></span><em class="property">type </em><code class="sig-name descname">MEMCACHED_HASH_CRC</code><a class="headerlink" href="#_CPPv418MEMCACHED_HASH_CRC" title="Permalink to this definition"></a><br /></dt>
232 <dd></dd></dl>
233
234 <dl class="cpp type">
235 <dt id="_CPPv422MEMCACHED_HASH_FNV1_64">
236 <span id="_CPPv322MEMCACHED_HASH_FNV1_64"></span><span id="_CPPv222MEMCACHED_HASH_FNV1_64"></span><span id="MEMCACHED_HASH_FNV1_64"></span><em class="property">type </em><code class="sig-name descname">MEMCACHED_HASH_FNV1_64</code><a class="headerlink" href="#_CPPv422MEMCACHED_HASH_FNV1_64" title="Permalink to this definition"></a><br /></dt>
237 <dd></dd></dl>
238
239 <dl class="cpp type">
240 <dt id="_CPPv423MEMCACHED_HASH_FNV1A_64">
241 <span id="_CPPv323MEMCACHED_HASH_FNV1A_64"></span><span id="_CPPv223MEMCACHED_HASH_FNV1A_64"></span><span id="MEMCACHED_HASH_FNV1A_64"></span><em class="property">type </em><code class="sig-name descname">MEMCACHED_HASH_FNV1A_64</code><a class="headerlink" href="#_CPPv423MEMCACHED_HASH_FNV1A_64" title="Permalink to this definition"></a><br /></dt>
242 <dd></dd></dl>
243
244 <dl class="cpp type">
245 <dt id="_CPPv422MEMCACHED_HASH_FNV1_32">
246 <span id="_CPPv322MEMCACHED_HASH_FNV1_32"></span><span id="_CPPv222MEMCACHED_HASH_FNV1_32"></span><span id="MEMCACHED_HASH_FNV1_32"></span><em class="property">type </em><code class="sig-name descname">MEMCACHED_HASH_FNV1_32</code><a class="headerlink" href="#_CPPv422MEMCACHED_HASH_FNV1_32" title="Permalink to this definition"></a><br /></dt>
247 <dd></dd></dl>
248
249 <dl class="cpp type">
250 <dt id="_CPPv423MEMCACHED_HASH_FNV1A_32">
251 <span id="_CPPv323MEMCACHED_HASH_FNV1A_32"></span><span id="_CPPv223MEMCACHED_HASH_FNV1A_32"></span><span id="MEMCACHED_HASH_FNV1A_32"></span><em class="property">type </em><code class="sig-name descname">MEMCACHED_HASH_FNV1A_32</code><a class="headerlink" href="#_CPPv423MEMCACHED_HASH_FNV1A_32" title="Permalink to this definition"></a><br /></dt>
252 <dd></dd></dl>
253
254 <dl class="cpp type">
255 <dt id="_CPPv422MEMCACHED_HASH_JENKINS">
256 <span id="_CPPv322MEMCACHED_HASH_JENKINS"></span><span id="_CPPv222MEMCACHED_HASH_JENKINS"></span><span id="MEMCACHED_HASH_JENKINS"></span><em class="property">type </em><code class="sig-name descname">MEMCACHED_HASH_JENKINS</code><a class="headerlink" href="#_CPPv422MEMCACHED_HASH_JENKINS" title="Permalink to this definition"></a><br /></dt>
257 <dd></dd></dl>
258
259 <dl class="cpp type">
260 <dt id="_CPPv421MEMCACHED_HASH_MURMUR">
261 <span id="_CPPv321MEMCACHED_HASH_MURMUR"></span><span id="_CPPv221MEMCACHED_HASH_MURMUR"></span><span id="MEMCACHED_HASH_MURMUR"></span><em class="property">type </em><code class="sig-name descname">MEMCACHED_HASH_MURMUR</code><a class="headerlink" href="#_CPPv421MEMCACHED_HASH_MURMUR" title="Permalink to this definition"></a><br /></dt>
262 <dd></dd></dl>
263
264 <dl class="cpp type">
265 <dt id="_CPPv420MEMCACHED_HASH_HSIEH">
266 <span id="_CPPv320MEMCACHED_HASH_HSIEH"></span><span id="_CPPv220MEMCACHED_HASH_HSIEH"></span><span id="MEMCACHED_HASH_HSIEH"></span><em class="property">type </em><code class="sig-name descname">MEMCACHED_HASH_HSIEH</code><a class="headerlink" href="#_CPPv420MEMCACHED_HASH_HSIEH" title="Permalink to this definition"></a><br /></dt>
267 <dd></dd></dl>
268
269 <dl class="cpp type">
270 <dt id="_CPPv422MEMCACHED_HASH_MURMUR3">
271 <span id="_CPPv322MEMCACHED_HASH_MURMUR3"></span><span id="_CPPv222MEMCACHED_HASH_MURMUR3"></span><span id="MEMCACHED_HASH_MURMUR3"></span><em class="property">type </em><code class="sig-name descname">MEMCACHED_HASH_MURMUR3</code><a class="headerlink" href="#_CPPv422MEMCACHED_HASH_MURMUR3" title="Permalink to this definition"></a><br /></dt>
272 <dd></dd></dl>
273
274 <p>Compile and link with -lmemcachedutil -lmemcached</p>
275 </div>
276 <div class="section" id="description">
277 <h2>DESCRIPTION<a class="headerlink" href="#description" title="Permalink to this headline"></a></h2>
278 <p><a class="reference internal" href="#_CPPv429memcached_generate_hash_valuePKc6size_t16memcached_hash_t" title="memcached_generate_hash_value"><code class="xref cpp cpp-func docutils literal notranslate"><span class="pre">memcached_generate_hash_value()</span></code></a> allows you to hash a key using one of
279 the hash functions defined in the library. This method is provided for
280 the convenience of higher-level language bindings and is not necessary
281 for normal memcache operations.</p>
282 <p>The allowed hash algorithm constants are listed in the manpage for
283 <a class="reference internal" href="memcached_behavior.html#_CPPv422memcached_behavior_setP12memcached_st20memcached_behavior_t8uint64_t" title="memcached_behavior_set"><code class="xref cpp cpp-func docutils literal notranslate"><span class="pre">memcached_behavior_set()</span></code></a>.</p>
284 <p><a class="reference internal" href="#_CPPv423memcached_generate_hashP12memcached_stPKc6size_t" title="memcached_generate_hash"><code class="xref cpp cpp-func docutils literal notranslate"><span class="pre">memcached_generate_hash()</span></code></a> takes a <a class="reference internal" href="memcached_create.html#_CPPv412memcached_st" title="memcached_st"><code class="xref cpp cpp-type docutils literal notranslate"><span class="pre">memcached_st</span></code></a> structure
285 and produces the hash value that would have been generated based on the
286 defaults of <a class="reference internal" href="memcached_create.html#_CPPv412memcached_st" title="memcached_st"><code class="xref cpp cpp-type docutils literal notranslate"><span class="pre">memcached_st</span></code></a>.</p>
287 <p>As of version 0.36 all hash methods have been placed into the library
288 libhashkit(3) which is linked with libmemcached(3). For more information please see its documentation.</p>
289 </div>
290 <div class="section" id="return-value">
291 <h2>RETURN VALUE<a class="headerlink" href="#return-value" title="Permalink to this headline"></a></h2>
292 <p>A 32-bit integer which is the result of hashing the given key.
293 For 64-bit hash algorithms, only the least-significant 32 bits are
294 returned.</p>
295 </div>
296 <div class="section" id="see-also">
297 <h2>SEE ALSO<a class="headerlink" href="#see-also" title="Permalink to this headline"></a></h2>
298 </div>
299 </div>
300
301
302 </div>
303
304 </div>
305 <footer>
306
307 <div class="rst-footer-buttons" role="navigation" aria-label="footer navigation">
308
309 <a href="memcached_sasl.html" class="btn btn-neutral float-right" title="SASL support" accesskey="n" rel="next">Next <span class="fa fa-arrow-circle-right"></span></a>
310
311
312 <a href="memcached_set_encoding_key.html" class="btn btn-neutral float-left" title="Set encryption key" accesskey="p" rel="prev"><span class="fa fa-arrow-circle-left"></span> Previous</a>
313
314 </div>
315
316
317 <hr/>
318
319 <div role="contentinfo">
320 <p>
321 &copy; <a href="../copyright.html">Copyright</a>
322
323 </p>
324 </div>
325 Built with <a href="http://sphinx-doc.org/">Sphinx</a> using a <a href="https://github.com/rtfd/sphinx_rtd_theme">theme</a> provided by <a href="https://readthedocs.org">Read the Docs</a>.
326
327 </footer>
328
329 </div>
330 </div>
331
332 </section>
333
334 </div>
335
336
337
338 <script type="text/javascript">
339 jQuery(function () {
340 SphinxRtdTheme.Navigation.enable(true);
341 });
342 </script>
343
344
345
346
347
348
349 </body>
350 </html>