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<li ><a href="#method-i-each_entry">#each_entry</a>
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<li ><a href="#method-i-seek">#seek</a>
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<h1 id="class-Gem::Package::TarReader" class="class">
class Gem::Package::TarReader
</h1>
<section class="description">
<p><a href="TarReader.html"><code>TarReader</code></a> reads tar files and allows iteration over their items</p>
</section>
<section id="5Buntitled-5D" class="documentation-section">
<section id="public-class-5Buntitled-5D-method-details" class="method-section">
<header>
<h3>Public Class Methods</h3>
</header>
<div id="method-c-new" class="method-detail ">
<div class="method-heading">
<span class="method-name">new</span><span
class="method-args">(io)</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<p>Creates a new tar file reader on <code>io</code> which needs to respond to pos, eof?, read, getc and pos=</p>
<div class="method-source-code" id="new-source">
<pre><span class="ruby-comment"># File lib/rubygems/package/tar_reader.rb, line 40</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">initialize</span>(<span class="ruby-identifier">io</span>)
<span class="ruby-ivar">@io</span> = <span class="ruby-identifier">io</span>
<span class="ruby-ivar">@init_pos</span> = <span class="ruby-identifier">io</span>.<span class="ruby-identifier">pos</span>
<span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
<div id="method-c-new" class="method-detail ">
<div class="method-heading">
<span class="method-name">new</span><span
class="method-args">(io) { |reader| ... }</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<p>Creates a new <a href="TarReader.html"><code>TarReader</code></a> on <code>io</code> and yields it to the block, if given.</p>
<div class="method-calls-super">
Calls superclass method
<a href="../../BasicObject.html#method-c-new"><code>BasicObject::new</code></a>
</div>
<div class="method-source-code" id="new-source">
<pre><span class="ruby-comment"># File lib/rubygems/package/tar_reader.rb, line 22</span>
<span class="ruby-keyword">def</span> <span class="ruby-keyword">self</span>.<span class="ruby-identifier ruby-title">new</span>(<span class="ruby-identifier">io</span>)
<span class="ruby-identifier">reader</span> = <span class="ruby-keyword">super</span>
<span class="ruby-keyword">return</span> <span class="ruby-identifier">reader</span> <span class="ruby-keyword">unless</span> <span class="ruby-identifier">block_given?</span>
<span class="ruby-keyword">begin</span>
<span class="ruby-keyword">yield</span> <span class="ruby-identifier">reader</span>
<span class="ruby-keyword">ensure</span>
<span class="ruby-identifier">reader</span>.<span class="ruby-identifier">close</span>
<span class="ruby-keyword">end</span>
<span class="ruby-keyword">nil</span>
<span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
</section>
<section id="public-instance-5Buntitled-5D-method-details" class="method-section">
<header>
<h3>Public Instance Methods</h3>
</header>
<div id="method-i-close" class="method-detail ">
<div class="method-heading">
<span class="method-name">close</span><span
class="method-args">()</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<p>Close the tar file</p>
<div class="method-source-code" id="close-source">
<pre><span class="ruby-comment"># File lib/rubygems/package/tar_reader.rb, line 48</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">close</span>
<span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
<div id="method-i-each" class="method-detail ">
<div class="method-heading">
<span class="method-name">each</span><span
class="method-args">() { |entry| ... }</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<p>Iterates over files in the tarball yielding each entry</p>
<div class="method-source-code" id="each-source">
<pre><span class="ruby-comment"># File lib/rubygems/package/tar_reader.rb, line 54</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">each</span>
<span class="ruby-keyword">return</span> <span class="ruby-identifier">enum_for</span> <span class="ruby-identifier">__method__</span> <span class="ruby-keyword">unless</span> <span class="ruby-identifier">block_given?</span>
<span class="ruby-identifier">use_seek</span> = <span class="ruby-ivar">@io</span>.<span class="ruby-identifier">respond_to?</span>(<span class="ruby-value">:seek</span>)
<span class="ruby-keyword">until</span> <span class="ruby-ivar">@io</span>.<span class="ruby-identifier">eof?</span> <span class="ruby-keyword">do</span>
<span class="ruby-identifier">header</span> = <span class="ruby-constant">Gem</span><span class="ruby-operator">::</span><span class="ruby-constant">Package</span><span class="ruby-operator">::</span><span class="ruby-constant">TarHeader</span>.<span class="ruby-identifier">from</span> <span class="ruby-ivar">@io</span>
<span class="ruby-keyword">return</span> <span class="ruby-keyword">if</span> <span class="ruby-identifier">header</span>.<span class="ruby-identifier">empty?</span>
<span class="ruby-identifier">entry</span> = <span class="ruby-constant">Gem</span><span class="ruby-operator">::</span><span class="ruby-constant">Package</span><span class="ruby-operator">::</span><span class="ruby-constant">TarReader</span><span class="ruby-operator">::</span><span class="ruby-constant">Entry</span>.<span class="ruby-identifier">new</span> <span class="ruby-identifier">header</span>, <span class="ruby-ivar">@io</span>
<span class="ruby-identifier">size</span> = <span class="ruby-identifier">entry</span>.<span class="ruby-identifier">header</span>.<span class="ruby-identifier">size</span>
<span class="ruby-keyword">yield</span> <span class="ruby-identifier">entry</span>
<span class="ruby-identifier">skip</span> = (<span class="ruby-value">512</span> <span class="ruby-operator">-</span> (<span class="ruby-identifier">size</span> <span class="ruby-operator">%</span> <span class="ruby-value">512</span>)) <span class="ruby-operator">%</span> <span class="ruby-value">512</span>
<span class="ruby-identifier">pending</span> = <span class="ruby-identifier">size</span> <span class="ruby-operator">-</span> <span class="ruby-identifier">entry</span>.<span class="ruby-identifier">bytes_read</span>
<span class="ruby-keyword">if</span> <span class="ruby-identifier">use_seek</span>
<span class="ruby-keyword">begin</span>
<span class="ruby-comment"># avoid reading if the @io supports seeking</span>
<span class="ruby-ivar">@io</span>.<span class="ruby-identifier">seek</span> <span class="ruby-identifier">pending</span>, <span class="ruby-constant">IO</span><span class="ruby-operator">::</span><span class="ruby-constant">SEEK_CUR</span>
<span class="ruby-identifier">pending</span> = <span class="ruby-value">0</span>
<span class="ruby-keyword">rescue</span> <span class="ruby-constant">Errno</span><span class="ruby-operator">::</span><span class="ruby-constant">EINVAL</span>
<span class="ruby-keyword">end</span>
<span class="ruby-keyword">end</span>
<span class="ruby-comment"># if seeking isn't supported or failed</span>
<span class="ruby-keyword">while</span> <span class="ruby-identifier">pending</span> <span class="ruby-operator">></span> <span class="ruby-value">0</span> <span class="ruby-keyword">do</span>
<span class="ruby-identifier">bytes_read</span> = <span class="ruby-ivar">@io</span>.<span class="ruby-identifier">read</span>([<span class="ruby-identifier">pending</span>, <span class="ruby-value">4096</span>].<span class="ruby-identifier">min</span>).<span class="ruby-identifier">size</span>
<span class="ruby-identifier">raise</span> <span class="ruby-constant">UnexpectedEOF</span> <span class="ruby-keyword">if</span> <span class="ruby-ivar">@io</span>.<span class="ruby-identifier">eof?</span>
<span class="ruby-identifier">pending</span> <span class="ruby-operator">-=</span> <span class="ruby-identifier">bytes_read</span>
<span class="ruby-keyword">end</span>
<span class="ruby-ivar">@io</span>.<span class="ruby-identifier">read</span> <span class="ruby-identifier">skip</span> <span class="ruby-comment"># discard trailing zeros</span>
<span class="ruby-comment"># make sure nobody can use #read, #getc or #rewind anymore</span>
<span class="ruby-identifier">entry</span>.<span class="ruby-identifier">close</span>
<span class="ruby-keyword">end</span>
<span class="ruby-keyword">end</span></pre>
</div>
</div>
<div class="aliases">
Also aliased as: <a href="TarReader.html#method-i-each_entry">each_entry</a>
</div>
</div>
<div id="method-i-each_entry" class="method-detail method-alias">
<div class="method-heading">
<span class="method-name">each_entry</span><span
class="method-args">()</span>
</div>
<div class="method-description">
</div>
<div class="aliases">
Alias for: <a href="TarReader.html#method-i-each">each</a>
</div>
</div>
<div id="method-i-rewind" class="method-detail ">
<div class="method-heading">
<span class="method-name">rewind</span><span
class="method-args">()</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<p>NOTE: Do not call <a href="TarReader.html#method-i-rewind"><code>rewind</code></a> during <a href="TarReader.html#method-i-each"><code>each</code></a></p>
<div class="method-source-code" id="rewind-source">
<pre><span class="ruby-comment"># File lib/rubygems/package/tar_reader.rb, line 99</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">rewind</span>
<span class="ruby-keyword">if</span> <span class="ruby-ivar">@init_pos</span> <span class="ruby-operator">==</span> <span class="ruby-value">0</span>
<span class="ruby-ivar">@io</span>.<span class="ruby-identifier">rewind</span>
<span class="ruby-keyword">else</span>
<span class="ruby-ivar">@io</span>.<span class="ruby-identifier">pos</span> = <span class="ruby-ivar">@init_pos</span>
<span class="ruby-keyword">end</span>
<span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
<div id="method-i-seek" class="method-detail ">
<div class="method-heading">
<span class="method-name">seek</span><span
class="method-args">(name) { |entry| ... }</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<p>Seeks through the tar file until it finds the <code>entry</code> with <code>name</code> and yields it. Rewinds the tar file to the beginning when the block terminates.</p>
<div class="method-source-code" id="seek-source">
<pre><span class="ruby-comment"># File lib/rubygems/package/tar_reader.rb, line 112</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">seek</span>(<span class="ruby-identifier">name</span>) <span class="ruby-comment"># :yields: entry</span>
<span class="ruby-identifier">found</span> = <span class="ruby-identifier">find</span> <span class="ruby-keyword">do</span> <span class="ruby-operator">|</span><span class="ruby-identifier">entry</span><span class="ruby-operator">|</span>
<span class="ruby-identifier">entry</span>.<span class="ruby-identifier">full_name</span> <span class="ruby-operator">==</span> <span class="ruby-identifier">name</span>
<span class="ruby-keyword">end</span>
<span class="ruby-keyword">return</span> <span class="ruby-keyword">unless</span> <span class="ruby-identifier">found</span>
<span class="ruby-keyword">return</span> <span class="ruby-keyword">yield</span> <span class="ruby-identifier">found</span>
<span class="ruby-keyword">ensure</span>
<span class="ruby-identifier">rewind</span>
<span class="ruby-keyword">end</span></pre>
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