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diff --git a/contrib/vorbis/doc/vorbisfile/callbacks.html b/contrib/vorbis/doc/vorbisfile/callbacks.html deleted file mode 100644 index 20ae55a..0000000 --- a/contrib/vorbis/doc/vorbisfile/callbacks.html +++ /dev/null @@ -1,121 +0,0 @@ -<html> - -<head> -<title>Vorbisfile - Callbacks and non-stdio I/O</title> -<link rel=stylesheet href="style.css" type="text/css"> -</head> - -<body bgcolor=white text=black link="#5555ff" alink="#5555ff" vlink="#5555ff"> -<table border=0 width=100%> -<tr> -<td><p class=tiny>Vorbisfile documentation</p></td> -<td align=right><p class=tiny>vorbisfile version 1.3.2 - 20101101</p></td> -</tr> -</table> - -<h1>Callbacks and non-stdio I/O</h1> - -Although stdio is convenient and nearly universally implemented as per -ANSI C, it is not suited to all or even most potential uses of Vorbis. -For additional flexibility, embedded applications may provide their -own I/O functions for use with Vorbisfile when stdio is unavailable or not -suitable. One common example is decoding a Vorbis stream from a -memory buffer.<p> - -Use custom I/O functions by populating an <a -href="ov_callbacks.html">ov_callbacks</a> structure and calling <a -href="ov_open_callbacks.html">ov_open_callbacks()</a> or <a -href="ov_test_callbacks.html">ov_test_callbacks()</a> rather than the -typical <a href="ov_open.html">ov_open()</a> or <a -href="ov_test.html">ov_test()</a>. Past the open call, use of -libvorbisfile is identical to using it with stdio. - -<h2>Read function</h2> - -The read-like function provided in the <tt>read_func</tt> field is -used to fetch the requested amount of data. It expects the fetch -operation to function similar to file-access, that is, a multiple read -operations will retrieve contiguous sequential pieces of data, -advancing a position cursor after each read.<p> - -The following behaviors are also expected:<p> -<ul> -<li>a return of '0' indicates end-of-data (if the by-thread errno is unset) -<li>short reads mean nothing special (short reads are not treated as error conditions) -<li>a return of zero with the by-thread errno set to nonzero indicates a read error -</ul> -<p> - -<h2>Seek function</h2> - -The seek-like function provided in the <tt>seek_func</tt> field is -used to request non-sequential data access by libvorbisfile, moving -the access cursor to the requested position. The seek function is -optional; if callbacks are only to handle non-seeking (streaming) data -or the application wishes to force streaming behavior, -<tt>seek_func</tt> and <tt>tell_func</tt> should be set to NULL. If -the seek function is non-NULL, libvorbisfile mandates the following -behavior: - -<ul> -<li>The seek function must always return -1 (failure) if the given -data abstraction is not seekable. It may choose to always return -1 -if the application desires libvorbisfile to treat the Vorbis data -strictly as a stream (which makes for a less expensive open -operation).<p> - -<li>If the seek function initially indicates seekability, it must -always succeed upon being given a valid seek request.<p> - -<li>The seek function must implement all of SEEK_SET, SEEK_CUR and -SEEK_END. The implementation of SEEK_END should set the access cursor -one past the last byte of accessible data, as would stdio -<tt>fseek()</tt><p> -</ul> - -<h2>Close function</h2> - -The close function should deallocate any access state used by the -passed in instance of the data access abstraction and invalidate the -instance handle. The close function is assumed to succeed; its return -code is not checked.<p> - -The <tt>close_func</tt> may be set to NULL to indicate that libvorbis -should not attempt to close the file/data handle in <a -href="ov_clear.html">ov_clear</a> but allow the application to handle -file/data access cleanup itself. For example, by passing the normal -stdio calls as callback functions, but passing a <tt>close_func</tt> -that is NULL or does nothing (as in the case of OV_CALLBACKS_NOCLOSE), an -application may call <a href="ov_clear.html">ov_clear()</a> and then -later <tt>fclose()</tt> the file originally passed to libvorbisfile. - -<h2>Tell function</h2> - -The tell function is intended to mimic the -behavior of <tt>ftell()</tt> and must return the byte position of the -next data byte that would be read. If the data access cursor is at -the end of the 'file' (pointing to one past the last byte of data, as -it would be after calling <tt>fseek(file,SEEK_END,0)</tt>), the tell -function must return the data position (and thus the total file size), -not an error.<p> - -The tell function need not be provided if the data IO abstraction is -not seekable, or the application wishes to force streaming -behavior. In this case, the <tt>tell_func</tt> and <tt>seek_func</tt> -fields should be set to NULL.<p> - -<br><br> -<hr noshade> -<table border=0 width=100%> -<tr valign=top> -<td><p class=tiny>copyright © 2000-2010 Xiph.Org</p></td> -<td align=right><p class=tiny><a href="http://www.xiph.org/ogg/vorbis/">Ogg Vorbis</a></p></td> -</tr><tr> -<td><p class=tiny>Vorbisfile documentation</p></td> -<td align=right><p class=tiny>vorbisfile version 1.3.2 - 20101101</p></td> -</tr> -</table> - -</body> - -</html> |