added more error codes. consolidated exception classes into one. moved over more places to use error_code instead of strings. fixed proper error handling for torrent_info
This commit is contained in:
Arvid Norberg
180
docs/manual.html
180
docs/manual.html
@@ -220,44 +220,46 @@
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<li><a class="reference internal" href="#invalid-torrent-file" id="id173">invalid_torrent_file</a></li>
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</ul>
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</li>
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<li><a class="reference internal" href="#storage-interface" id="id174">storage_interface</a><ul>
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<li><a class="reference internal" href="#initialize" id="id175">initialize()</a></li>
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<li><a class="reference internal" href="#readv-writev" id="id176">readv() writev()</a></li>
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<li><a class="reference internal" href="#id12" id="id177">move_storage()</a></li>
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<li><a class="reference internal" href="#verify-resume-data" id="id178">verify_resume_data()</a></li>
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<li><a class="reference internal" href="#write-resume-data" id="id179">write_resume_data()</a></li>
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<li><a class="reference internal" href="#move-slot" id="id180">move_slot()</a></li>
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<li><a class="reference internal" href="#swap-slots" id="id181">swap_slots()</a></li>
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<li><a class="reference internal" href="#swap-slots3" id="id182">swap_slots3()</a></li>
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<li><a class="reference internal" href="#hash-for-slot" id="id183">hash_for_slot()</a></li>
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<li><a class="reference internal" href="#id13" id="id184">rename_file()</a></li>
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<li><a class="reference internal" href="#release-files" id="id185">release_files()</a></li>
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<li><a class="reference internal" href="#delete-files" id="id186">delete_files()</a></li>
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<li><a class="reference internal" href="#error-code" id="id174">error_code</a></li>
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<li><a class="reference internal" href="#storage-interface" id="id175">storage_interface</a><ul>
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<li><a class="reference internal" href="#initialize" id="id176">initialize()</a></li>
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<li><a class="reference internal" href="#readv-writev" id="id177">readv() writev()</a></li>
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<li><a class="reference internal" href="#sparse-end" id="id178">sparse_end()</a></li>
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<li><a class="reference internal" href="#id12" id="id179">move_storage()</a></li>
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<li><a class="reference internal" href="#verify-resume-data" id="id180">verify_resume_data()</a></li>
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<li><a class="reference internal" href="#write-resume-data" id="id181">write_resume_data()</a></li>
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<li><a class="reference internal" href="#move-slot" id="id182">move_slot()</a></li>
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<li><a class="reference internal" href="#swap-slots" id="id183">swap_slots()</a></li>
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<li><a class="reference internal" href="#swap-slots3" id="id184">swap_slots3()</a></li>
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<li><a class="reference internal" href="#hash-for-slot" id="id185">hash_for_slot()</a></li>
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<li><a class="reference internal" href="#id13" id="id186">rename_file()</a></li>
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<li><a class="reference internal" href="#release-files" id="id187">release_files()</a></li>
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<li><a class="reference internal" href="#delete-files" id="id188">delete_files()</a></li>
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</ul>
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</li>
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<li><a class="reference internal" href="#magnet-links" id="id187">magnet links</a></li>
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<li><a class="reference internal" href="#queuing" id="id188">queuing</a><ul>
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<li><a class="reference internal" href="#downloading" id="id189">downloading</a></li>
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<li><a class="reference internal" href="#seeding" id="id190">seeding</a></li>
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<li><a class="reference internal" href="#magnet-links" id="id189">magnet links</a></li>
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<li><a class="reference internal" href="#queuing" id="id190">queuing</a><ul>
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<li><a class="reference internal" href="#downloading" id="id191">downloading</a></li>
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<li><a class="reference internal" href="#seeding" id="id192">seeding</a></li>
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</ul>
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</li>
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<li><a class="reference internal" href="#fast-resume" id="id191">fast resume</a><ul>
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<li><a class="reference internal" href="#file-format" id="id192">file format</a></li>
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<li><a class="reference internal" href="#fast-resume" id="id193">fast resume</a><ul>
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<li><a class="reference internal" href="#file-format" id="id194">file format</a></li>
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</ul>
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</li>
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<li><a class="reference internal" href="#threads" id="id193">threads</a></li>
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<li><a class="reference internal" href="#storage-allocation" id="id194">storage allocation</a><ul>
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<li><a class="reference internal" href="#sparse-allocation" id="id195">sparse allocation</a></li>
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<li><a class="reference internal" href="#full-allocation" id="id196">full allocation</a></li>
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<li><a class="reference internal" href="#compact-allocation" id="id197">compact allocation</a></li>
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<li><a class="reference internal" href="#threads" id="id195">threads</a></li>
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<li><a class="reference internal" href="#storage-allocation" id="id196">storage allocation</a><ul>
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<li><a class="reference internal" href="#sparse-allocation" id="id197">sparse allocation</a></li>
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<li><a class="reference internal" href="#full-allocation" id="id198">full allocation</a></li>
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<li><a class="reference internal" href="#compact-allocation" id="id199">compact allocation</a></li>
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</ul>
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</li>
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<li><a class="reference internal" href="#extensions" id="id198">extensions</a><ul>
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<li><a class="reference internal" href="#metadata-from-peers" id="id199">metadata from peers</a></li>
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<li><a class="reference internal" href="#http-seeding" id="id200">HTTP seeding</a></li>
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<li><a class="reference internal" href="#extensions" id="id200">extensions</a><ul>
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<li><a class="reference internal" href="#metadata-from-peers" id="id201">metadata from peers</a></li>
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<li><a class="reference internal" href="#http-seeding" id="id202">HTTP seeding</a></li>
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</ul>
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</li>
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<li><a class="reference internal" href="#filename-checks" id="id201">filename checks</a></li>
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<li><a class="reference internal" href="#filename-checks" id="id203">filename checks</a></li>
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</ul>
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</div>
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<div class="section" id="overview">
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@@ -1394,12 +1396,20 @@ class torrent_info
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{
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public:
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// these constructors throws exceptions on error
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torrent_info(sha1_hash const& info_hash);
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torrent_info(lazy_entry const& torrent_file);
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torrent_info(char const* buffer, int size);
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torrent_info(boost::filesystem::path const& filename);
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torrent_info(boost::filesystem::wpath const& filename);
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// these constructors sets the error code on error
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torrent_info(sha1_hash const& info_hash, error_code& ec);
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torrent_info(lazy_entry const& torrent_file, error_code& ec);
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torrent_info(char const* buffer, int size, error_code& ec);
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torrent_info(fs::path const& filename, error_code& ec);
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torrent_info(fs::wpath const& filename, error_code& ec);
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void add_tracker(std::string const& url, int tier = 0);
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std::vector<announce_entry> const& trackers() const;
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@@ -1463,6 +1473,12 @@ torrent_info(lazy_entry const& torrent_file);
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torrent_info(char const* buffer, int size);
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torrent_info(boost::filesystem::path const& filename);
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torrent_info(boost::filesystem::wpath const& filename);
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torrent_info(sha1_hash const& info_hash, error_code& ec);
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torrent_info(lazy_entry const& torrent_file, error_code& ec);
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torrent_info(char const* buffer, int size, error_code& ec);
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torrent_info(fs::path const& filename, error_code& ec);
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torrent_info(fs::wpath const& filename, error_code& ec);
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</pre>
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</blockquote>
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<p>The constructor that takes an info-hash will initialize the info-hash to the given value,
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@@ -1478,6 +1494,11 @@ initialize the torrent_info object for you.</p>
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<p>The version that takes a filename will simply load the torrent file and decode it inside
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the constructor, for convenience. This might not be the most suitable for applications that
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want to be able to report detailed errors on what might go wrong.</p>
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<p>The overloads that takes an <tt class="docutils literal"><span class="pre">error_code</span> <span class="pre">const&</span></tt> never throws if an error occur, they
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will simply set the error code to describe what went wrong and not fully initialize the
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torrent_info object. The overloads that do not take the extra <a class="reference internal" href="#error-code">error_code</a> parameter will
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always throw if an error occurs. These overloads are not available when building without
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exception support.</p>
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</div>
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<div class="section" id="add-tracker">
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<h2>add_tracker()</h2>
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@@ -4774,10 +4795,100 @@ doesn't meet the requirements on what information has to be present in a torrent
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struct invalid_torrent_file: std::exception
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{
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const char* what() const throw();
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boost::system::error_code error() const;
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};
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</pre>
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</div>
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</div>
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<div class="section" id="error-code">
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<h1>error_code</h1>
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<p>libtorrent uses boost.system's <tt class="docutils literal"><span class="pre">error_code</span></tt> class to represent errors. libtorrent has
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its own error category (<tt class="docutils literal"><span class="pre">libtorrent::libtorrent_category</span></tt>) whith the following error
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codes:</p>
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<table border="1" class="docutils">
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<colgroup>
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<col width="6%" />
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<col width="28%" />
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<col width="66%" />
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</colgroup>
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<thead valign="bottom">
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<tr><th class="head">code</th>
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<th class="head">symbol</th>
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<th class="head">description</th>
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</tr>
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</thead>
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<tbody valign="top">
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<tr><td>0</td>
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<td>no_error</td>
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<td>Not an error</td>
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</tr>
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<tr><td>1</td>
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<td>file_collision</td>
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<td>Two torrents has files which end up overwriting each other</td>
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</tr>
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<tr><td>2</td>
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<td>failed_hash_check</td>
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<td>A piece did not match its piece hash</td>
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</tr>
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<tr><td>3</td>
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<td>torrent_is_no_dict</td>
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<td>The .torrent file does not contain a bencoded dictionary at
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its top level</td>
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</tr>
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<tr><td>4</td>
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<td>torrent_missing_info</td>
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<td>The .torrent file does not have an <tt class="docutils literal"><span class="pre">info</span></tt> dictionary</td>
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</tr>
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<tr><td>5</td>
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<td>torrent_info_no_dict</td>
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<td>The .torrent file's <tt class="docutils literal"><span class="pre">info</span></tt> entry is not a dictionary</td>
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</tr>
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<tr><td>6</td>
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<td>torrent_missing_piece_length</td>
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<td>The .torrent file does not have a <tt class="docutils literal"><span class="pre">piece</span> <span class="pre">length</span></tt> entry</td>
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</tr>
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<tr><td>7</td>
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<td>torrent_missing_name</td>
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<td>The .torrent file does not have a <tt class="docutils literal"><span class="pre">name</span></tt> entry</td>
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</tr>
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<tr><td>8</td>
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<td>torrent_invalid_name</td>
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<td>The .torrent file's name entry is invalid</td>
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</tr>
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<tr><td>9</td>
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<td>torrent_invalid_length</td>
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<td>The length of a file, or of the whole .torrent file is invalid.
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Either negative or not an integer</td>
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</tr>
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<tr><td>10</td>
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<td>torrent_file_parse_failed</td>
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<td>Failed to parse a file entry in the .torrent</td>
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</tr>
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<tr><td>11</td>
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<td>torrent_missing_pieces</td>
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<td>The <tt class="docutils literal"><span class="pre">pieces</span></tt> field is missing or invalid in the .torrent file</td>
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</tr>
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<tr><td>12</td>
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<td>torrent_invalid_hashes</td>
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<td>The <tt class="docutils literal"><span class="pre">pieces</span></tt> string has incorrect length</td>
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</tr>
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<tr><td>13</td>
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<td>too_many_pieces_in_torrent</td>
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<td>The .torrent file has more pieces than is supported by libtorrent</td>
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</tr>
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<tr><td>14</td>
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<td>invalid_swarm_metadata</td>
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<td>The metadata (.torrent file) that was received from the swarm
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matched the info-hash, but failed to be parsed</td>
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</tr>
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<tr><td>15</td>
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<td>invalid_bencoding</td>
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<td>The file or buffer is not correctly bencoded</td>
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</tr>
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</tbody>
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</table>
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<p>The names of these error codes are declared in then <tt class="docutils literal"><span class="pre">libtorrent::errors</span></tt> namespace.</p>
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</div>
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<div class="section" id="storage-interface">
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<h1>storage_interface</h1>
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<p>The storage interface is a pure virtual class that can be implemented to
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@@ -4789,6 +4900,7 @@ struct storage_interface
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virtual bool initialize(bool allocate_files) = 0;
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virtual int readv(file::iovec_t const* bufs, int slot, int offset, int num_bufs) = 0;
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virtual int writev(file::iovec_t const* bufs, int slot, int offset, int num_bufs) = 0;
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virtual int sparse_end(int start) const;
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virtual bool move_storage(fs::path save_path) = 0;
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virtual bool verify_resume_data(lazy_entry const& rd, std::string& error) = 0;
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virtual bool write_resume_data(entry& rd) const = 0;
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@@ -4851,6 +4963,18 @@ exceptions when it's not. Specifically if the read cache is disabled/or full and
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client requests unaligned data, or the file itself is not aligned in the torrent.
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Most clients request aligned data.</p>
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</div>
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<div class="section" id="sparse-end">
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<h2>sparse_end()</h2>
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<blockquote>
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<pre class="literal-block">
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int sparse_end(int start) const;
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</pre>
|
||||
</blockquote>
|
||||
<p>This function is optional. It is supposed to return the first piece, starting at
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<tt class="docutils literal"><span class="pre">start</span></tt> that is fully contained within a data-region on disk (i.e. non-sparse
|
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region). The purpose of this is to skip parts of files that can be known to contain
|
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zeros when checking files.</p>
|
||||
</div>
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<div class="section" id="id12">
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<h2>move_storage()</h2>
|
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<blockquote>
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||||
|
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152
docs/manual.rst
152
docs/manual.rst
@@ -1255,12 +1255,20 @@ The ``torrent_info`` has the following synopsis::
|
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{
|
||||
public:
|
||||
|
||||
// these constructors throws exceptions on error
|
||||
torrent_info(sha1_hash const& info_hash);
|
||||
torrent_info(lazy_entry const& torrent_file);
|
||||
torrent_info(char const* buffer, int size);
|
||||
torrent_info(boost::filesystem::path const& filename);
|
||||
torrent_info(boost::filesystem::wpath const& filename);
|
||||
|
||||
// these constructors sets the error code on error
|
||||
torrent_info(sha1_hash const& info_hash, error_code& ec);
|
||||
torrent_info(lazy_entry const& torrent_file, error_code& ec);
|
||||
torrent_info(char const* buffer, int size, error_code& ec);
|
||||
torrent_info(fs::path const& filename, error_code& ec);
|
||||
torrent_info(fs::wpath const& filename, error_code& ec);
|
||||
|
||||
void add_tracker(std::string const& url, int tier = 0);
|
||||
std::vector<announce_entry> const& trackers() const;
|
||||
|
||||
@@ -1326,6 +1334,12 @@ torrent_info()
|
||||
torrent_info(boost::filesystem::path const& filename);
|
||||
torrent_info(boost::filesystem::wpath const& filename);
|
||||
|
||||
torrent_info(sha1_hash const& info_hash, error_code& ec);
|
||||
torrent_info(lazy_entry const& torrent_file, error_code& ec);
|
||||
torrent_info(char const* buffer, int size, error_code& ec);
|
||||
torrent_info(fs::path const& filename, error_code& ec);
|
||||
torrent_info(fs::wpath const& filename, error_code& ec);
|
||||
|
||||
The constructor that takes an info-hash will initialize the info-hash to the given value,
|
||||
but leave all other fields empty. This is used internally when downloading torrents without
|
||||
the metadata. The metadata will be created by libtorrent as soon as it has been downloaded
|
||||
@@ -1343,6 +1357,12 @@ The version that takes a filename will simply load the torrent file and decode i
|
||||
the constructor, for convenience. This might not be the most suitable for applications that
|
||||
want to be able to report detailed errors on what might go wrong.
|
||||
|
||||
The overloads that takes an ``error_code const&`` never throws if an error occur, they
|
||||
will simply set the error code to describe what went wrong and not fully initialize the
|
||||
torrent_info object. The overloads that do not take the extra error_code_ parameter will
|
||||
always throw if an error occurs. These overloads are not available when building without
|
||||
exception support.
|
||||
|
||||
|
||||
add_tracker()
|
||||
-------------
|
||||
@@ -4914,80 +4934,84 @@ including ``<libtorrent/alert.hpp>``.
|
||||
exceptions
|
||||
==========
|
||||
|
||||
There are a number of exceptions that can be thrown from different places in libtorrent,
|
||||
here's a complete list with description.
|
||||
Many functions in libtorrent have two versions, one that throws exceptions on
|
||||
errors and one that takes an ``error_code`` reference which is filled with the
|
||||
error code on errors.
|
||||
|
||||
There is one exception class that is used for errors in libtorrent, it is based
|
||||
on boost.system's ``error_code`` class to carry the error code.
|
||||
|
||||
invalid_handle
|
||||
--------------
|
||||
|
||||
This exception is thrown when querying information from a torrent_handle_ that hasn't
|
||||
been initialized or that has become invalid.
|
||||
|
||||
::
|
||||
|
||||
struct invalid_handle: std::exception
|
||||
{
|
||||
const char* what() const throw();
|
||||
};
|
||||
|
||||
|
||||
duplicate_torrent
|
||||
-----------------
|
||||
|
||||
This is thrown by `add_torrent()`_ if the torrent already has been added to
|
||||
the session. Since `remove_torrent()`_ is asynchronous, this exception may
|
||||
be thrown if the torrent is removed and then immediately added again.
|
||||
|
||||
::
|
||||
|
||||
struct duplicate_torrent: std::exception
|
||||
{
|
||||
const char* what() const throw();
|
||||
};
|
||||
|
||||
|
||||
invalid_encoding
|
||||
----------------
|
||||
|
||||
This is thrown by ``bdecode()`` if the input data is not a valid bencoding.
|
||||
|
||||
::
|
||||
|
||||
struct invalid_encoding: std::exception
|
||||
{
|
||||
const char* what() const throw();
|
||||
};
|
||||
|
||||
|
||||
type_error
|
||||
----------
|
||||
|
||||
This is thrown from the accessors of ``entry`` if the data type of the ``entry`` doesn't
|
||||
match the type you want to extract from it.
|
||||
|
||||
::
|
||||
|
||||
struct type_error: std::runtime_error
|
||||
{
|
||||
type_error(const char* error);
|
||||
};
|
||||
|
||||
|
||||
invalid_torrent_file
|
||||
libtorrent_exception
|
||||
--------------------
|
||||
|
||||
This exception is thrown from the constructor of ``torrent_info`` if the given bencoded information
|
||||
doesn't meet the requirements on what information has to be present in a torrent file.
|
||||
|
||||
::
|
||||
|
||||
struct invalid_torrent_file: std::exception
|
||||
struct libtorrent_exception: std::exception
|
||||
{
|
||||
const char* what() const throw();
|
||||
libtorrent_exception(error_code const& s);
|
||||
virtual const char* what() const throw();
|
||||
virtual ~libtorrent_exception() throw() {}
|
||||
boost::system::error_code error() const;
|
||||
};
|
||||
|
||||
|
||||
error_code
|
||||
==========
|
||||
|
||||
libtorrent uses boost.system's ``error_code`` class to represent errors. libtorrent has
|
||||
its own error category (``libtorrent::libtorrent_category``) whith the following error
|
||||
codes:
|
||||
|
||||
====== ============================ =================================================================
|
||||
code symbol description
|
||||
====== ============================ =================================================================
|
||||
0 no_error Not an error
|
||||
------ ---------------------------- -----------------------------------------------------------------
|
||||
1 file_collision Two torrents has files which end up overwriting each other
|
||||
------ ---------------------------- -----------------------------------------------------------------
|
||||
2 failed_hash_check A piece did not match its piece hash
|
||||
------ ---------------------------- -----------------------------------------------------------------
|
||||
3 torrent_is_no_dict The .torrent file does not contain a bencoded dictionary at
|
||||
its top level
|
||||
------ ---------------------------- -----------------------------------------------------------------
|
||||
4 torrent_missing_info The .torrent file does not have an ``info`` dictionary
|
||||
------ ---------------------------- -----------------------------------------------------------------
|
||||
5 torrent_info_no_dict The .torrent file's ``info`` entry is not a dictionary
|
||||
------ ---------------------------- -----------------------------------------------------------------
|
||||
6 torrent_missing_piece_length The .torrent file does not have a ``piece length`` entry
|
||||
------ ---------------------------- -----------------------------------------------------------------
|
||||
7 torrent_missing_name The .torrent file does not have a ``name`` entry
|
||||
------ ---------------------------- -----------------------------------------------------------------
|
||||
8 torrent_invalid_name The .torrent file's name entry is invalid
|
||||
------ ---------------------------- -----------------------------------------------------------------
|
||||
9 torrent_invalid_length The length of a file, or of the whole .torrent file is invalid.
|
||||
Either negative or not an integer
|
||||
------ ---------------------------- -----------------------------------------------------------------
|
||||
10 torrent_file_parse_failed Failed to parse a file entry in the .torrent
|
||||
------ ---------------------------- -----------------------------------------------------------------
|
||||
11 torrent_missing_pieces The ``pieces`` field is missing or invalid in the .torrent file
|
||||
------ ---------------------------- -----------------------------------------------------------------
|
||||
12 torrent_invalid_hashes The ``pieces`` string has incorrect length
|
||||
------ ---------------------------- -----------------------------------------------------------------
|
||||
13 too_many_pieces_in_torrent The .torrent file has more pieces than is supported by libtorrent
|
||||
------ ---------------------------- -----------------------------------------------------------------
|
||||
14 invalid_swarm_metadata The metadata (.torrent file) that was received from the swarm
|
||||
matched the info-hash, but failed to be parsed
|
||||
------ ---------------------------- -----------------------------------------------------------------
|
||||
15 invalid_bencoding The file or buffer is not correctly bencoded
|
||||
------ ---------------------------- -----------------------------------------------------------------
|
||||
16 no_files_in_torrent The .torrent file does not contain any files
|
||||
------ ---------------------------- -----------------------------------------------------------------
|
||||
17 invalid_escaped_string The string was not properly url-encoded as expected
|
||||
------ ---------------------------- -----------------------------------------------------------------
|
||||
18 session_is_closing Operation is not permitted since the session is shutting down
|
||||
------ ---------------------------- -----------------------------------------------------------------
|
||||
19 duplicate_torrent There's already a torrent with that info-hash added to the
|
||||
session
|
||||
====== ============================ =================================================================
|
||||
|
||||
The names of these error codes are declared in then ``libtorrent::errors`` namespace.
|
||||
|
||||
storage_interface
|
||||
=================
|
||||
|
||||
|
||||
Reference in New Issue
Block a user