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  16         <p>Next: <a href="pswgen05.html">05 - Building Generator Module</a>, Previous: <a href="pswgen03.html">03 - Generator Module</a></p>
  17
  18         <h1>eVaf Tutorial</h1>
  19
  20         <h2>04 - Generator Module</h2>
  21
  22         <p>Now we are going to implement all the classes declared in the <tt>module.h</tt>. Create the <tt>module.cpp</tt> file
  23         in the <tt>src/apps/PswGen/Generator</tt> directory. We obviously include the <tt>module.h</tt> header file, but also
  24         the <tt>QtCore</tt> header file for any non-GUI Qt classes.</p>
  25
  26 <pre class="hl"><span class="hl com">/**</span>
  27 <span class="hl com"> * &#64;file src/apps/PswGen/Generator/module.cpp</span>
  28 <span class="hl com"> */</span>
  29
  30 <span class="hl ppc">#include</span> <span class="hl pps">&quot;module.h&quot;</span><span class="hl ppc"></span>
  31
  32 <span class="hl ppc">#include &lt;QtCore&gt;</span></pre>
  33
  34         <p>All the eVaf modules need to include version information. This is common for all the modules and we can simply
  35         copy existing version info files from another eVaf module:</p>
  36
  37         <pre>evaf/src/apps/PswGen/Generator $ <code>cp ../../../plugins/SdiWindow/version.{h,rc} .</code></pre>
  38
  39         <p>The <tt>version.h</tt> file contains version information for the module. The <tt>version.rc</tt> is for Windows
  40         builds only and embeds the same version information into the dll or exe file. Modify the copied <tt>version.h</tt>
  41         file for our new module. The <tt>version.rc</tt> file uses the values from the <tt>version.h</tt> and does not
  42         need to be touched.</p>
  43
  44 <pre class="hl"><span class="hl com">/**</span>
  45 <span class="hl com"> * &#64;file src/apps/PswGen/Generator/version.h</span>
  46 <span class="hl com"> */</span>
  47 <span class="hl ppc">#ifndef __PSWGEN_GENERATOR_VERSION_H</span>
  48 <span class="hl ppc">#define __PSWGEN_GENERATOR_VERSION_H</span>
  49
  50 <span class="hl ppc">#include &lt;version_rc.h&gt;</span>
  51
  52 <span class="hl com">/**</span>
  53 <span class="hl com"> * Module/library version number in the form major,minor,release,build</span>
  54 <span class="hl com"> */</span>
  55 <span class="hl ppc">#define VER_FILE_VERSION                0,1,1,1</span>
  56
  57 <span class="hl com">/**</span>
  58 <span class="hl com"> * Module/library version number in the string format (shall end with \0)</span>
  59 <span class="hl com"> */</span>
  60 <span class="hl ppc">#define VER_FILE_VERSION_STR</span>            <span class="hl pps">&quot;0.1.1.1\0&quot;</span><span class="hl ppc"></span>
  61
  62 <span class="hl com">/**</span>
  63 <span class="hl com"> * Module/library name (shall end with \0)</span>
  64 <span class="hl com"> */</span>
  65 <span class="hl ppc">#define VER_MODULE_NAME_STR</span>             <span class="hl pps">&quot;PswGen\0&quot;</span><span class="hl ppc"></span>
  66
  67 <span class="hl com">/**</span>
  68 <span class="hl com"> * Module type (see version_rc.h for all the types)</span>
  69 <span class="hl com"> */</span>
  70 <span class="hl ppc">#define VER_MODULE_TYPE                 MT_GENERIC</span>
  71
  72 <span class="hl com">/**</span>
  73 <span class="hl com"> * Module type in the string format (see version_rc for all the types)</span>
  74 <span class="hl com"> */</span>
  75 <span class="hl ppc">#define VER_MODULE_TYPE_STR             MT_GENERIC</span>
  76
  77 <span class="hl com">/**</span>
  78 <span class="hl com"> * Original file name for windows (shall end with \0)</span>
  79 <span class="hl com"> */</span>
  80 <span class="hl ppc">#define VER_ORIGINAL_FILE_NAME_STR</span>      <span class="hl pps">&quot;PswGen.dll\0&quot;</span><span class="hl ppc"></span>
  81
  82 <span class="hl com">/**</span>
  83 <span class="hl com"> * Description of the module/library (shall end with \0)</span>
  84 <span class="hl com"> */</span>
  85 <span class="hl ppc">#define VER_FILE_DESCRIPTION_STR</span>         <span class="hl pps">&quot;Module that generates strong passwords using MD5 hashes.\0&quot;</span><span class="hl ppc"></span>
  86
  87 <span class="hl ppc">#endif</span> <span class="hl slc">// version.h</span><span class="hl ppc"></span></pre>
  88
  89         <p>Then include the version info file in the <tt>module.cpp</tt> file and use the <tt>VER_EXPORT_VERSION_INFO()</tt> macro
  90         to export version information from the module. This macro defines a public function that all the eVaf modules export and
  91         is used to collect version information from them. In your modules you only need to modify the <tt>version.h</tt> file and then
  92         use the <tt>VER_EXPORT_VERSION_INFO()</tt> macro once somewhere in your code.</p>
  93
  94 <pre class="hl"><span class="hl ppc">#include</span> <span class="hl pps">&quot;version.h&quot;</span><span class="hl ppc"></span>
  95
  96 <span class="hl kwd">VER_EXPORT_VERSION_INFO</span><span class="hl opt">()</span></pre>
  97
  98         <p>To make the <tt>Module</tt> class a proper Qt plugin, we use the <tt>Q_EXPORT_PLUGIN2</tt> macro. The name of the module is already
  99         defined in the <tt>version.h</tt> header file as <tt>VER_MODULE_NAME_STR</tt>.
 100
 101         <pre class="hl"><span class="hl kwd">Q_EXPORT_PLUGIN2</span><span class="hl opt">(</span>VER_MODULE_NAME_STR<span class="hl opt">,</span> eVaf<span class="hl opt">::</span>PswGen<span class="hl opt">::</span>Generator<span class="hl opt">::</span>Module<span class="hl opt">)</span></pre>
 102
 103         <p>We make our life easier with several <tt>using namespace</tt> keywords:</p>
 104
 105 <pre class="hl"><span class="hl kwa">using namespace</span> eVaf<span class="hl opt">;</span>
 106 <span class="hl kwa">using namespace</span> eVaf<span class="hl opt">::</span>PswGen<span class="hl opt">;</span>
 107 <span class="hl kwa">using namespace</span> eVaf<span class="hl opt">::</span>PswGen<span class="hl opt">::</span>Generator<span class="hl opt">;</span></pre>
 108
 109         <p>The Module class needs to instantiate the <tt>iGenerator</tt> interface in the constructor. We also need to set
 110         the QObject's name property to the name of the plugin by combining the name of the module with the name of the class.
 111         While the application would work without the name property, it makes our life much easier if the name property is set.</p>
 112
 113         <p>Finally, we output an info message telling that the object was created. Every eVaf module and class is expected to
 114         output info messages when they are created, destroyed, initialized or destroyed.</p>
 115
 116 <pre class="hl">Module<span class="hl opt">::</span><span class="hl kwd">Module</span><span class="hl opt">()</span>
 117     <span class="hl opt">:</span> Plugins<span class="hl opt">::</span><span class="hl kwd">iPlugin</span><span class="hl opt">()</span>
 118 <span class="hl opt">{</span>
 119     <span class="hl kwd">setObjectName</span><span class="hl opt">(</span><span class="hl kwd">QString</span><span class="hl opt">(</span><span class="hl str">&quot;%1.%2&quot;</span><span class="hl opt">).</span><span class="hl kwd">arg</span><span class="hl opt">(</span>VER_MODULE_NAME_STR<span class="hl opt">).</span><span class="hl kwd">arg</span><span class="hl opt">(</span>__FUNCTION__<span class="hl opt">));</span>
 120
 121     mGenerator <span class="hl opt">=</span> <span class="hl kwa">new</span> Internal<span class="hl opt">::</span>GeneratorImpl<span class="hl opt">;</span>
 122
 123     <span class="hl kwd">EVAF_INFO</span><span class="hl opt">(</span><span class="hl str">&quot;%s created&quot;</span><span class="hl opt">,</span> <span class="hl kwd">qPrintable</span><span class="hl opt">(</span><span class="hl kwd">objectName</span><span class="hl opt">()));</span>
 124 <span class="hl opt">}</span></pre>
 125
 126         <p>The <tt>EVAF_INFO</tt> macro comes from the <tt>Common/iLogger</tt> header file ane we need to include it:</p>
 127
 128 <pre class="hl"><span class="hl ppc">#include &lt;Common/iLogger&gt;</span></pre>
 129
 130         <p>The destructor should delete the <tt>iGenerator</tt> interface object, which we created in the constructor. The common
 131         rule is that any resources allocated in the constructor shall be released in the destructor, preferrably in the opposite
 132         order, ie. the first resource allocated in the constructor is released last in the destructor.</tt>
 133
 134 <pre class="hl">Module<span class="hl opt">::~</span><span class="hl kwd">Module</span><span class="hl opt">()</span>
 135 <span class="hl opt">{</span>
 136     <span class="hl kwa">delete</span> mGenerator<span class="hl opt">;</span>
 137
 138     <span class="hl kwd">EVAF_INFO</span><span class="hl opt">(</span><span class="hl str">&quot;%s destroyed&quot;</span><span class="hl opt">,</span> <span class="hl kwd">qPrintable</span><span class="hl opt">(</span><span class="hl kwd">objectName</span><span class="hl opt">()));</span>
 139 <span class="hl opt">}</span></pre>
 140
 141         <p>We also need to implement <tt>init()</tt> and <tt>done()</tt> functions, which are used to initialize and finalize modules.
 142         They are similar to the constructor and destructor with two major differences:</p>
 143         <ol>
 144             <li>The <tt>init()</tt> function can fail and return <tt>false</tt> to indicate a failure. eVaf does not use exceptions and
 145             this is the only way for a module to fail without terminating the whole application. A failed module will be disabled
 146             and the rest of the application can still run if it can.</li>
 147             <li>eVaf modules are loaded in two steps. At first, all the modules are created, which means that all the objects
 148             are constructed. Only then will eVaf call <tt>init()</tt> functions meaning that when the <tt>init()</tt> function is
 149             called, all the modules are already loaded and instantiated. Interfaces and resources from other modules that might be not
 150             available when the object is created, are available when the <tt>init()</tt> function is called.</li>
 151         </ol>
 152
 153         <p>The rule for <tt>init()</tt> and <tt>done()</tt> functions is the same than for constructors and destructors -- any resource
 154         allocated in the <tt>init()</tt> function shall be released in the <tt>done()</tt> function and preferrably in the opposite
 155         order.</p>
 156
 157         <p>This simple module needs no extra resources to be allocated and our <tt>init()</tt> and <tt>done()</tt> functions can be
 158         the following:</p>
 159
 160 <pre class="hl"><span class="hl kwb">bool</span> Module<span class="hl opt">::</span><span class="hl kwd">init</span><span class="hl opt">(</span>QString <span class="hl kwb">const</span> <span class="hl opt">&amp;</span> args<span class="hl opt">)</span>
 161 <span class="hl opt">{</span>
 162     <span class="hl kwd">Q_UNUSED</span><span class="hl opt">(</span>args<span class="hl opt">);</span>
 163
 164     <span class="hl kwd">EVAF_INFO</span><span class="hl opt">(</span><span class="hl str">&quot;%s initialized&quot;</span><span class="hl opt">,</span> <span class="hl kwd">qPrintable</span><span class="hl opt">(</span><span class="hl kwd">objectName</span><span class="hl opt">()));</span>
 165
 166     <span class="hl kwa">return true</span><span class="hl opt">;</span>
 167 <span class="hl opt">}</span>
 168
 169 <span class="hl kwb">void</span> Module<span class="hl opt">::</span><span class="hl kwd">done</span><span class="hl opt">()</span>
 170 <span class="hl opt">{</span>
 171     <span class="hl kwd">EVAF_INFO</span><span class="hl opt">(</span><span class="hl str">&quot;%s finalized&quot;</span><span class="hl opt">,</span> <span class="hl kwd">qPrintable</span><span class="hl opt">(</span><span class="hl kwd">objectName</span><span class="hl opt">()));</span>
 172 <span class="hl opt">}</span></pre>
 173
 174         <p>We continue by implementing the <tt>iGenerator</tt> interface. There are no resources to be allocated in the constructor
 175         and we just set the QObject's name property and output the info message.</p>
 176
 177         <p>We also register the <tt>iGenerator</tt> interface in the global registry so that other modules can query for it and
 178         use our interface. This is done by using the <tt>Common::iRegistry</tt> interface, which we need to include:</p>
 179
 180 <pre class="hl"><span class="hl ppc">#include &lt;Common/iRegistry&gt;</span></pre>
 181
 182         <p>The <tt>GeneratorImpl</tt> class was declared in the <tt>eVaf::PswGen::Generator::Internal</tt> namespace, so we need
 183         another <tt>using namespace</tt> keyword before the implementation of the class:</p>
 184
 185 <pre class="hl"><span class="hl kwa">using namespace</span> eVaf<span class="hl opt">::</span>PswGen<span class="hl opt">::</span>Generator<span class="hl opt">::</span>Internal<span class="hl opt">;</span>
 186
 187 GeneratorImpl<span class="hl opt">::</span><span class="hl kwd">GeneratorImpl</span><span class="hl opt">()</span>
 188     <span class="hl opt">:</span> <span class="hl kwd">iGenerator</span><span class="hl opt">()</span>
 189 <span class="hl opt">{</span>
 190     <span class="hl kwd">setObjectName</span><span class="hl opt">(</span><span class="hl kwd">QString</span><span class="hl opt">(</span><span class="hl str">&quot;%1.iGenerator&quot;</span><span class="hl opt">).</span><span class="hl kwd">arg</span><span class="hl opt">(</span>VER_MODULE_NAME_STR<span class="hl opt">));</span>
 191
 192     Common<span class="hl opt">::</span>iRegistry<span class="hl opt">::</span><span class="hl kwd">instance</span><span class="hl opt">()-&gt;</span><span class="hl kwd">registerInterface</span><span class="hl opt">(</span><span class="hl str">&quot;iGenerator&quot;</span><span class="hl opt">,</span> <span class="hl kwa">this</span><span class="hl opt">);</span>
 193
 194     <span class="hl kwd">EVAF_INFO</span><span class="hl opt">(</span><span class="hl str">&quot;%s created&quot;</span><span class="hl opt">,</span> <span class="hl kwd">qPrintable</span><span class="hl opt">(</span><span class="hl kwd">objectName</span><span class="hl opt">()));</span>
 195 <span class="hl opt">}</span>
 196
 197 GeneratorImpl<span class="hl opt">::~</span><span class="hl kwd">GeneratorImpl</span><span class="hl opt">()</span>
 198 <span class="hl opt">{</span>
 199     <span class="hl kwd">EVAF_INFO</span><span class="hl opt">(</span><span class="hl str">&quot;%s destroyed&quot;</span><span class="hl opt">,</span> <span class="hl kwd">qPrintable</span><span class="hl opt">(</span><span class="hl kwd">objectName</span><span class="hl opt">()));</span>
 200 <span class="hl opt">}</span></pre>
 201
 202     <p>Finally, we write the <tt>generatePassword</tt> function that does the actual job of the module.</p>
 203
 204     <p>We use the MD5 cryptographic hash function to calculate a hash value over the <tt>name</tt> and <tt>masterPassword</tt> values.
 205     The result, which is a binary blob, needs to be convert into something that can be used as a password and we use base 64 encoding
 206     for this and cut the result to the requested length:</p>
 207
 208 <pre class="hl">QString GeneratorImpl<span class="hl opt">::</span><span class="hl kwd">generatePassword</span><span class="hl opt">(</span>QString <span class="hl kwb">const</span> <span class="hl opt">&amp;</span> name<span class="hl opt">,</span> QString <span class="hl kwb">const</span> <span class="hl opt">&amp;</span> masterPassword<span class="hl opt">,</span> <span class="hl kwb">int</span> length<span class="hl opt">,</span> uint flags<span class="hl opt">)</span> <span class="hl kwb">const</span>
 209 <span class="hl opt">{</span>
 210     <span class="hl kwd">Q_UNUSED</span><span class="hl opt">(</span>flags<span class="hl opt">);</span>
 211
 212     QByteArray inputString <span class="hl opt">=</span> <span class="hl kwd">QString</span><span class="hl opt">(</span><span class="hl str">&quot;%1%2&quot;</span><span class="hl opt">).</span><span class="hl kwd">arg</span><span class="hl opt">(</span>name<span class="hl opt">).</span><span class="hl kwd">arg</span><span class="hl opt">(</span>masterPassword<span class="hl opt">).</span><span class="hl kwd">toLatin1</span><span class="hl opt">();</span>
 213     QCryptographicHash <span class="hl kwd">hash</span><span class="hl opt">(</span>QCryptographicHash<span class="hl opt">::</span>Md5<span class="hl opt">);</span>
 214     hash<span class="hl opt">.</span><span class="hl kwd">addData</span><span class="hl opt">(</span>inputString<span class="hl opt">);</span>
 215     QByteArray result <span class="hl opt">=</span> hash<span class="hl opt">.</span><span class="hl kwd">result</span><span class="hl opt">().</span><span class="hl kwd">toBase64</span><span class="hl opt">();</span>
 216     <span class="hl kwa">if</span> <span class="hl opt">(</span>length <span class="hl opt">&gt;</span> <span class="hl num">0</span><span class="hl opt">)</span>
 217         <span class="hl kwa">return</span> result<span class="hl opt">.</span><span class="hl kwd">left</span><span class="hl opt">(</span>length<span class="hl opt">);</span>
 218     <span class="hl kwa">else</span>
 219         <span class="hl kwa">return</span> result<span class="hl opt">;</span>
 220 <span class="hl opt">}</span></pre>
 221
 222     <p>We also know now the maximum length of the generated password, which is 24. Go back to the <tt>module.h</tt> header file and
 223     modify the <tt>GeneratorImpl::maxLength()</tt> function:</p>
 224
 225 <pre class="hl"><span class="hl kwc">virtual</span> <span class="hl kwb">int</span> <span class="hl kwd">maxLength</span><span class="hl opt">()</span> <span class="hl kwb">const</span> <span class="hl opt">{</span> <span class="hl kwa">return</span> <span class="hl num">24</span><span class="hl opt">; }</span></pre>
 226
 227     <p>Here is the final <tt>module.cpp</tt> file:</p>
 228
 229 <pre class="hl"><span class="hl com">/**</span>
 230 <span class="hl com"> * &#64;file src/apps/PswGen/Generator/module.cpp</span>
 231 <span class="hl com"> */</span>
 232
 233 <span class="hl ppc">#include</span> <span class="hl pps">&quot;module.h&quot;</span><span class="hl ppc"></span>
 234 <span class="hl ppc">#include</span> <span class="hl pps">&quot;version.h&quot;</span><span class="hl ppc"></span>
 235
 236 <span class="hl ppc">#include &lt;Common/iLogger&gt;</span>
 237 <span class="hl ppc">#include &lt;Common/iRegistry&gt;</span>
 238
 239 <span class="hl ppc">#include &lt;QtCore&gt;</span>
 240
 241 <span class="hl kwd">VER_EXPORT_VERSION_INFO</span><span class="hl opt">()</span>
 242 <span class="hl kwd">Q_EXPORT_PLUGIN2</span><span class="hl opt">(</span>VER_MODULE_NAME_STR<span class="hl opt">,</span> eVaf<span class="hl opt">::</span>PswGen<span class="hl opt">::</span>Generator<span class="hl opt">::</span>Module<span class="hl opt">)</span>
 243
 244 <span class="hl kwa">using namespace</span> eVaf<span class="hl opt">;</span>
 245 <span class="hl kwa">using namespace</span> eVaf<span class="hl opt">::</span>PswGen<span class="hl opt">;</span>
 246 <span class="hl kwa">using namespace</span> eVaf<span class="hl opt">::</span>PswGen<span class="hl opt">::</span>Generator<span class="hl opt">;</span>
 247
 248 Module<span class="hl opt">::</span><span class="hl kwd">Module</span><span class="hl opt">()</span>
 249     <span class="hl opt">:</span> Plugins<span class="hl opt">::</span><span class="hl kwd">iPlugin</span><span class="hl opt">()</span>
 250 <span class="hl opt">{</span>
 251     <span class="hl kwd">setObjectName</span><span class="hl opt">(</span><span class="hl kwd">QString</span><span class="hl opt">(</span><span class="hl str">&quot;%1.%2&quot;</span><span class="hl opt">).</span><span class="hl kwd">arg</span><span class="hl opt">(</span>VER_MODULE_NAME_STR<span class="hl opt">).</span><span class="hl kwd">arg</span><span class="hl opt">(</span>__FUNCTION__<span class="hl opt">));</span>
 252
 253     mGenerator <span class="hl opt">=</span> <span class="hl kwa">new</span> Internal<span class="hl opt">::</span>GeneratorImpl<span class="hl opt">;</span>
 254
 255     <span class="hl kwd">EVAF_INFO</span><span class="hl opt">(</span><span class="hl str">&quot;%s created&quot;</span><span class="hl opt">,</span> <span class="hl kwd">qPrintable</span><span class="hl opt">(</span><span class="hl kwd">objectName</span><span class="hl opt">()));</span>
 256 <span class="hl opt">}</span>
 257
 258 Module<span class="hl opt">::~</span><span class="hl kwd">Module</span><span class="hl opt">()</span>
 259 <span class="hl opt">{</span>
 260     <span class="hl kwa">delete</span> mGenerator<span class="hl opt">;</span>
 261
 262     <span class="hl kwd">EVAF_INFO</span><span class="hl opt">(</span><span class="hl str">&quot;%s destroyed&quot;</span><span class="hl opt">,</span> <span class="hl kwd">qPrintable</span><span class="hl opt">(</span><span class="hl kwd">objectName</span><span class="hl opt">()));</span>
 263 <span class="hl opt">}</span>
 264
 265 <span class="hl kwb">bool</span> Module<span class="hl opt">::</span><span class="hl kwd">init</span><span class="hl opt">(</span>QString <span class="hl kwb">const</span> <span class="hl opt">&amp;</span> args<span class="hl opt">)</span>
 266 <span class="hl opt">{</span>
 267     <span class="hl kwd">Q_UNUSED</span><span class="hl opt">(</span>args<span class="hl opt">);</span>
 268
 269     <span class="hl kwd">EVAF_INFO</span><span class="hl opt">(</span><span class="hl str">&quot;%s initialized&quot;</span><span class="hl opt">,</span> <span class="hl kwd">qPrintable</span><span class="hl opt">(</span><span class="hl kwd">objectName</span><span class="hl opt">()));</span>
 270
 271     <span class="hl kwa">return true</span><span class="hl opt">;</span>
 272 <span class="hl opt">}</span>
 273
 274 <span class="hl kwb">void</span> Module<span class="hl opt">::</span><span class="hl kwd">done</span><span class="hl opt">()</span>
 275 <span class="hl opt">{</span>
 276     <span class="hl kwd">EVAF_INFO</span><span class="hl opt">(</span><span class="hl str">&quot;%s finalized&quot;</span><span class="hl opt">,</span> <span class="hl kwd">qPrintable</span><span class="hl opt">(</span><span class="hl kwd">objectName</span><span class="hl opt">()));</span>
 277 <span class="hl opt">}</span>
 278
 279 <span class="hl kwa">using namespace</span> eVaf<span class="hl opt">::</span>PswGen<span class="hl opt">::</span>Generator<span class="hl opt">::</span>Internal<span class="hl opt">;</span>
 280
 281 GeneratorImpl<span class="hl opt">::</span><span class="hl kwd">GeneratorImpl</span><span class="hl opt">()</span>
 282     <span class="hl opt">:</span> <span class="hl kwd">iGenerator</span><span class="hl opt">()</span>
 283 <span class="hl opt">{</span>
 284     <span class="hl kwd">setObjectName</span><span class="hl opt">(</span><span class="hl kwd">QString</span><span class="hl opt">(</span><span class="hl str">&quot;%1.iGenerator&quot;</span><span class="hl opt">).</span><span class="hl kwd">arg</span><span class="hl opt">(</span>VER_MODULE_NAME_STR<span class="hl opt">));</span>
 285
 286     Common<span class="hl opt">::</span>iRegistry<span class="hl opt">::</span><span class="hl kwd">instance</span><span class="hl opt">()-&gt;</span><span class="hl kwd">registerInterface</span><span class="hl opt">(</span><span class="hl str">&quot;iGenerator&quot;</span><span class="hl opt">,</span> <span class="hl kwa">this</span><span class="hl opt">);</span>
 287
 288     <span class="hl kwd">EVAF_INFO</span><span class="hl opt">(</span><span class="hl str">&quot;%s created&quot;</span><span class="hl opt">,</span> <span class="hl kwd">qPrintable</span><span class="hl opt">(</span><span class="hl kwd">objectName</span><span class="hl opt">()));</span>
 289 <span class="hl opt">}</span>
 290
 291 GeneratorImpl<span class="hl opt">::~</span><span class="hl kwd">GeneratorImpl</span><span class="hl opt">()</span>
 292 <span class="hl opt">{</span>
 293     <span class="hl kwd">EVAF_INFO</span><span class="hl opt">(</span><span class="hl str">&quot;%s destroyed&quot;</span><span class="hl opt">,</span> <span class="hl kwd">qPrintable</span><span class="hl opt">(</span><span class="hl kwd">objectName</span><span class="hl opt">()));</span>
 294 <span class="hl opt">}</span>
 295
 296 QString GeneratorImpl<span class="hl opt">::</span><span class="hl kwd">generatePassword</span><span class="hl opt">(</span>QString <span class="hl kwb">const</span> <span class="hl opt">&amp;</span> name<span class="hl opt">,</span> QString <span class="hl kwb">const</span> <span class="hl opt">&amp;</span> masterPassword<span class="hl opt">,</span> <span class="hl kwb">int</span> length<span class="hl opt">,</span> uint flags<span class="hl opt">)</span> <span class="hl kwb">const</span>
 297 <span class="hl opt">{</span>
 298     <span class="hl kwd">Q_UNUSED</span><span class="hl opt">(</span>flags<span class="hl opt">);</span>
 299
 300     QByteArray inputString <span class="hl opt">=</span> <span class="hl kwd">QString</span><span class="hl opt">(</span><span class="hl str">&quot;%1%2&quot;</span><span class="hl opt">).</span><span class="hl kwd">arg</span><span class="hl opt">(</span>name<span class="hl opt">).</span><span class="hl kwd">arg</span><span class="hl opt">(</span>masterPassword<span class="hl opt">).</span><span class="hl kwd">toLatin1</span><span class="hl opt">();</span>
 301     QCryptographicHash <span class="hl kwd">hash</span><span class="hl opt">(</span>QCryptographicHash<span class="hl opt">::</span>Md5<span class="hl opt">);</span>
 302     hash<span class="hl opt">.</span><span class="hl kwd">addData</span><span class="hl opt">(</span>inputString<span class="hl opt">);</span>
 303     QByteArray result <span class="hl opt">=</span> hash<span class="hl opt">.</span><span class="hl kwd">result</span><span class="hl opt">().</span><span class="hl kwd">toBase64</span><span class="hl opt">();</span>
 304     <span class="hl kwa">if</span> <span class="hl opt">(</span>length <span class="hl opt">&gt;</span> <span class="hl num">0</span><span class="hl opt">)</span>
 305         <span class="hl kwa">return</span> result<span class="hl opt">.</span><span class="hl kwd">left</span><span class="hl opt">(</span>length<span class="hl opt">);</span>
 306     <span class="hl kwa">else</span>
 307         <span class="hl kwa">return</span> result<span class="hl opt">;</span>
 308 <span class="hl opt">}</span></pre>
 309
 310         <p>Next -- <a href="pswgen05.html">05 - Building Generator Module</a>.</p>
 311
 312     </body>
 313 </html>