<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "https://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/xhtml;charset=UTF-8"/> <meta http-equiv="X-UA-Compatible" content="IE=9"/> <meta name="generator" content="Doxygen 1.8.15"/> <meta name="viewport" content="width=device-width, initial-scale=1"/> <title>apt: Acquire system {{{</title> <link href="tabs.css" rel="stylesheet" type="text/css"/> <script type="text/javascript" src="jquery.js"></script> <script type="text/javascript" src="dynsections.js"></script> <link href="doxygen.css" rel="stylesheet" type="text/css" /> </head> <body> <div id="top"><!-- do not remove this div, it is closed by doxygen! --> <div id="titlearea"> <table cellspacing="0" cellpadding="0"> <tbody> <tr style="height: 56px;"> <td id="projectalign" style="padding-left: 0.5em;"> <div id="projectname">apt  <span id="projectnumber">1.4.6</span> </div> <div id="projectbrief">commandline package manager</div> </td> </tr> </tbody> </table> </div> <!-- end header part --> <!-- Generated by Doxygen 1.8.15 --> <script type="text/javascript" src="menudata.js"></script> <script type="text/javascript" src="menu.js"></script> <script type="text/javascript"> /* @license magnet:?xt=urn:btih:cf05388f2679ee054f2beb29a391d25f4e673ac3&dn=gpl-2.0.txt GPL-v2 */ $(function() { initMenu('',false,false,'search.php','Search'); }); /* @license-end */</script> <div id="main-nav"></div> </div><!-- top --> <div class="header"> <div class="summary"> <a href="#files">Files</a> | <a href="#nested-classes">Classes</a> </div> <div class="headertitle"> <div class="title">Acquire system {{{</div> </div> </div><!--header--> <div class="contents"> <p>The Acquire system is responsible for retrieving files from local or remote URIs and postprocessing them (for instance, verifying their authenticity). The core class in this system is <a class="el" href="classpkgAcquire.xhtml" title="The core download scheduler. {{{.">pkgAcquire</a>, which is responsible for managing the download queues during the download. There is at least one download queue for each supported protocol; protocols such as http may provide one queue per host. <a href="#details">More...</a></p> <table class="memberdecls"> <tr class="heading"><td colspan="2"><h2 class="groupheader"><a name="files"></a> Files</h2></td></tr> <tr class="memitem:acquire-item_8h"><td class="memItemLeft" align="right" valign="top">file  </td><td class="memItemRight" valign="bottom"><a class="el" href="acquire-item_8h.xhtml">acquire-item.h</a></td></tr> <tr class="separator:"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:acquire-method_8h"><td class="memItemLeft" align="right" valign="top">file  </td><td class="memItemRight" valign="bottom"><a class="el" href="acquire-method_8h.xhtml">acquire-method.h</a></td></tr> <tr class="separator:"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:acquire-worker_8h"><td class="memItemLeft" align="right" valign="top">file  </td><td class="memItemRight" valign="bottom"><a class="el" href="acquire-worker_8h.xhtml">acquire-worker.h</a></td></tr> <tr class="separator:"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:acquire_8h"><td class="memItemLeft" align="right" valign="top">file  </td><td class="memItemRight" valign="bottom"><a class="el" href="acquire_8h.xhtml">acquire.h</a></td></tr> <tr class="separator:"><td class="memSeparator" colspan="2"> </td></tr> </table><table class="memberdecls"> <tr class="heading"><td colspan="2"><h2 class="groupheader"><a name="nested-classes"></a> Classes</h2></td></tr> <tr class="memitem:"><td class="memItemLeft" align="right" valign="top">class  </td><td class="memItemRight" valign="bottom"><a class="el" href="classpkgAcquire_1_1Item.xhtml">pkgAcquire::Item</a></td></tr> <tr class="memdesc:"><td class="mdescLeft"> </td><td class="mdescRight">Represents the process by which a <a class="el" href="classpkgAcquire.xhtml" title="The core download scheduler. {{{.">pkgAcquire</a> object should retrieve a file or a collection of files. <a href="classpkgAcquire_1_1Item.xhtml#details">More...</a><br /></td></tr> <tr class="separator:"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:"><td class="memItemLeft" align="right" valign="top">class  </td><td class="memItemRight" valign="bottom"><a class="el" href="classpkgAcqTransactionItem.xhtml">pkgAcqTransactionItem</a></td></tr> <tr class="memdesc:"><td class="mdescLeft"> </td><td class="mdescRight">baseclass for the indexes files to manage them all together <a href="classpkgAcqTransactionItem.xhtml#details">More...</a><br /></td></tr> <tr class="separator:"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:"><td class="memItemLeft" align="right" valign="top">class  </td><td class="memItemRight" valign="bottom"><a class="el" href="classpkgAcqMetaBase.xhtml">pkgAcqMetaBase</a></td></tr> <tr class="memdesc:"><td class="mdescLeft"> </td><td class="mdescRight">the manager of a transaction <a href="classpkgAcqMetaBase.xhtml#details">More...</a><br /></td></tr> <tr class="separator:"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:"><td class="memItemLeft" align="right" valign="top">class  </td><td class="memItemRight" valign="bottom"><a class="el" href="classpkgAcqMetaIndex.xhtml">pkgAcqMetaIndex</a></td></tr> <tr class="memdesc:"><td class="mdescLeft"> </td><td class="mdescRight">An item that is responsible for downloading the meta-index {{{ file (i.e., Release) itself and verifying its signature. <a href="classpkgAcqMetaIndex.xhtml#details">More...</a><br /></td></tr> <tr class="separator:"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:"><td class="memItemLeft" align="right" valign="top">class  </td><td class="memItemRight" valign="bottom"><a class="el" href="classpkgAcqMetaSig.xhtml">pkgAcqMetaSig</a></td></tr> <tr class="memdesc:"><td class="mdescLeft"> </td><td class="mdescRight">An acquire item that downloads the detached signature {{{ of a meta-index (Release) file, then queues up the release file itself. <a href="classpkgAcqMetaSig.xhtml#details">More...</a><br /></td></tr> <tr class="separator:"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:"><td class="memItemLeft" align="right" valign="top">class  </td><td class="memItemRight" valign="bottom"><a class="el" href="classpkgAcqMetaClearSig.xhtml">pkgAcqMetaClearSig</a></td></tr> <tr class="memdesc:"><td class="mdescLeft"> </td><td class="mdescRight">An item repsonsible for downloading clearsigned metaindexes {{{. <a href="classpkgAcqMetaClearSig.xhtml#details">More...</a><br /></td></tr> <tr class="separator:"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:"><td class="memItemLeft" align="right" valign="top">class  </td><td class="memItemRight" valign="bottom"><a class="el" href="classpkgAcqBaseIndex.xhtml">pkgAcqBaseIndex</a></td></tr> <tr class="memdesc:"><td class="mdescLeft"> </td><td class="mdescRight">Common base class for all classes that deal with fetching indexes {{{. <a href="classpkgAcqBaseIndex.xhtml#details">More...</a><br /></td></tr> <tr class="separator:"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:"><td class="memItemLeft" align="right" valign="top">class  </td><td class="memItemRight" valign="bottom"><a class="el" href="classpkgAcqIndex.xhtml">pkgAcqIndex</a></td></tr> <tr class="memdesc:"><td class="mdescLeft"> </td><td class="mdescRight">An acquire item that is responsible for fetching an index {{{ file (e.g., Packages or Sources). <a href="classpkgAcqIndex.xhtml#details">More...</a><br /></td></tr> <tr class="separator:"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:"><td class="memItemLeft" align="right" valign="top">class  </td><td class="memItemRight" valign="bottom"><a class="el" href="classpkgAcqDiffIndex.xhtml">pkgAcqDiffIndex</a></td></tr> <tr class="memdesc:"><td class="mdescLeft"> </td><td class="mdescRight">An item that is responsible for fetching an index file of {{{ package list diffs and starting the package list's download. <a href="classpkgAcqDiffIndex.xhtml#details">More...</a><br /></td></tr> <tr class="separator:"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:"><td class="memItemLeft" align="right" valign="top">struct  </td><td class="memItemRight" valign="bottom"><a class="el" href="structDiffInfo.xhtml">DiffInfo</a></td></tr> <tr class="separator:"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:"><td class="memItemLeft" align="right" valign="top">class  </td><td class="memItemRight" valign="bottom"><a class="el" href="classpkgAcqIndexMergeDiffs.xhtml">pkgAcqIndexMergeDiffs</a></td></tr> <tr class="memdesc:"><td class="mdescLeft"> </td><td class="mdescRight">An item that is responsible for fetching client-merge patches {{{ that need to be applied to a given package index file. <a href="classpkgAcqIndexMergeDiffs.xhtml#details">More...</a><br /></td></tr> <tr class="separator:"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:"><td class="memItemLeft" align="right" valign="top">class  </td><td class="memItemRight" valign="bottom"><a class="el" href="classpkgAcqIndexDiffs.xhtml">pkgAcqIndexDiffs</a></td></tr> <tr class="memdesc:"><td class="mdescLeft"> </td><td class="mdescRight">An item that is responsible for fetching server-merge patches {{{ that need to be applied to a given package index file. <a href="classpkgAcqIndexDiffs.xhtml#details">More...</a><br /></td></tr> <tr class="separator:"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:"><td class="memItemLeft" align="right" valign="top">class  </td><td class="memItemRight" valign="bottom"><a class="el" href="classpkgAcqArchive.xhtml">pkgAcqArchive</a></td></tr> <tr class="memdesc:"><td class="mdescLeft"> </td><td class="mdescRight">An item that is responsible for fetching a package file. {{{. <a href="classpkgAcqArchive.xhtml#details">More...</a><br /></td></tr> <tr class="separator:"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:"><td class="memItemLeft" align="right" valign="top">class  </td><td class="memItemRight" valign="bottom"><a class="el" href="classpkgAcqChangelog.xhtml">pkgAcqChangelog</a></td></tr> <tr class="memdesc:"><td class="mdescLeft"> </td><td class="mdescRight">Retrieve the changelog for the given version {{{. <a href="classpkgAcqChangelog.xhtml#details">More...</a><br /></td></tr> <tr class="separator:"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:"><td class="memItemLeft" align="right" valign="top">class  </td><td class="memItemRight" valign="bottom"><a class="el" href="classpkgAcqFile.xhtml">pkgAcqFile</a></td></tr> <tr class="memdesc:"><td class="mdescLeft"> </td><td class="mdescRight">Retrieve an arbitrary file to the current directory. {{{. <a href="classpkgAcqFile.xhtml#details">More...</a><br /></td></tr> <tr class="separator:"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:"><td class="memItemLeft" align="right" valign="top">class  </td><td class="memItemRight" valign="bottom"><a class="el" href="classpkgAcqMethod.xhtml">pkgAcqMethod</a></td></tr> <tr class="separator:"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:"><td class="memItemLeft" align="right" valign="top">class  </td><td class="memItemRight" valign="bottom"><a class="el" href="classpkgAcquire_1_1Worker.xhtml">pkgAcquire::Worker</a></td></tr> <tr class="memdesc:"><td class="mdescLeft"> </td><td class="mdescRight">A fetch subprocess. <a href="classpkgAcquire_1_1Worker.xhtml#details">More...</a><br /></td></tr> <tr class="separator:"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:"><td class="memItemLeft" align="right" valign="top">class  </td><td class="memItemRight" valign="bottom"><a class="el" href="classpkgAcquire.xhtml">pkgAcquire</a></td></tr> <tr class="memdesc:"><td class="mdescLeft"> </td><td class="mdescRight">The core download scheduler. {{{. <a href="classpkgAcquire.xhtml#details">More...</a><br /></td></tr> <tr class="separator:"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:"><td class="memItemLeft" align="right" valign="top">struct  </td><td class="memItemRight" valign="bottom"><a class="el" href="structpkgAcquire_1_1MethodConfig.xhtml">pkgAcquire::MethodConfig</a></td></tr> <tr class="memdesc:"><td class="mdescLeft"> </td><td class="mdescRight">Information about the properties of a single acquire method. {{{. <a href="structpkgAcquire_1_1MethodConfig.xhtml#details">More...</a><br /></td></tr> <tr class="separator:"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:"><td class="memItemLeft" align="right" valign="top">class  </td><td class="memItemRight" valign="bottom"><a class="el" href="classpkgAcquire_1_1UriIterator.xhtml">pkgAcquire::UriIterator</a></td></tr> <tr class="memdesc:"><td class="mdescLeft"> </td><td class="mdescRight">Iterates over all the URIs being fetched by a <a class="el" href="classpkgAcquire.xhtml" title="The core download scheduler. {{{.">pkgAcquire</a> object. {{{. <a href="classpkgAcquire_1_1UriIterator.xhtml#details">More...</a><br /></td></tr> <tr class="separator:"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:"><td class="memItemLeft" align="right" valign="top">class  </td><td class="memItemRight" valign="bottom"><a class="el" href="classpkgAcquire_1_1Queue.xhtml">pkgAcquire::Queue</a></td></tr> <tr class="memdesc:"><td class="mdescLeft"> </td><td class="mdescRight">A single download queue in a <a class="el" href="classpkgAcquire.xhtml" title="The core download scheduler. {{{.">pkgAcquire</a> object. {{{. <a href="classpkgAcquire_1_1Queue.xhtml#details">More...</a><br /></td></tr> <tr class="separator:"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:"><td class="memItemLeft" align="right" valign="top">struct  </td><td class="memItemRight" valign="bottom"><a class="el" href="structpkgAcquire_1_1ItemDesc.xhtml">pkgAcquire::ItemDesc</a></td></tr> <tr class="memdesc:"><td class="mdescLeft"> </td><td class="mdescRight">Represents a single download source from which an item should be downloaded. <a href="structpkgAcquire_1_1ItemDesc.xhtml#details">More...</a><br /></td></tr> <tr class="separator:"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:"><td class="memItemLeft" align="right" valign="top">class  </td><td class="memItemRight" valign="bottom"><a class="el" href="classpkgAcquireStatus.xhtml">pkgAcquireStatus</a></td></tr> <tr class="memdesc:"><td class="mdescLeft"> </td><td class="mdescRight">A monitor object for downloads controlled by the <a class="el" href="classpkgAcquire.xhtml" title="The core download scheduler. {{{.">pkgAcquire</a> class. {{{. <a href="classpkgAcquireStatus.xhtml#details">More...</a><br /></td></tr> <tr class="separator:"><td class="memSeparator" colspan="2"> </td></tr> </table> <a name="details" id="details"></a><h2 class="groupheader">Detailed Description</h2> <p>The Acquire system is responsible for retrieving files from local or remote URIs and postprocessing them (for instance, verifying their authenticity). The core class in this system is <a class="el" href="classpkgAcquire.xhtml" title="The core download scheduler. {{{.">pkgAcquire</a>, which is responsible for managing the download queues during the download. There is at least one download queue for each supported protocol; protocols such as http may provide one queue per host. </p> <p>Each file to download is represented by a subclass of <a class="el" href="classpkgAcquire_1_1Item.xhtml" title="Represents the process by which a pkgAcquire object should retrieve a file or a collection of files.">pkgAcquire::Item</a>. The files add themselves to the download queue(s) by providing their <a class="el" href="classURI.xhtml">URI</a> information to <a class="el" href="classpkgAcquire_1_1Item.xhtml#a3d592ee597936699b45a5b4356740c33" title="Insert this item into its owner's queue.">pkgAcquire::Item::QueueURI</a>, which calls <a class="el" href="classpkgAcquire.xhtml#adff4865b0b932d7c8dae0aee44006c13" title="Insert the given fetch request into the appropriate queue.">pkgAcquire::Enqueue</a>.</p> <p>Once the system is set up, the Run method will spawn subprocesses to handle the enqueued URIs; the scheduler will then take items from the queues and feed them into the handlers until the queues are empty.</p> <dl class="todo"><dt><b><a class="el" href="todo.xhtml#_todo000015">Todo:</a></b></dt><dd>Acquire supports inserting an object into several queues at once, but it is not clear what its behavior in this case is, and no subclass of <a class="el" href="classpkgAcquire_1_1Item.xhtml" title="Represents the process by which a pkgAcquire object should retrieve a file or a collection of files.">pkgAcquire::Item</a> seems to actually use this capability. </dd></dl> </div><!-- contents --> <!-- start footer part --> <hr class="footer"/><address class="footer"><small> Generated by  <a href="http://www.doxygen.org/index.html"> <img class="footer" src="doxygen.png" alt="doxygen"/> </a> 1.8.15 </small></address> </body> </html>