317 lines
51 KiB
HTML
317 lines
51 KiB
HTML
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
|
|
<html>
|
|
<head>
|
|
<title>Binary Files</title>
|
|
<meta name="viewport" content="width=device-width initial-scale=1">
|
|
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
|
|
<meta http-equiv="Content-Language" content="en-gb">
|
|
<link href="../inweb.css" rel="stylesheet" rev="stylesheet" type="text/css">
|
|
|
|
</head>
|
|
<body>
|
|
<nav role="navigation">
|
|
<h1><a href="../index.html">
|
|
<img src="../..//docs/docs-src/Figures/Octagram184x184.png" width=72 height=72">
|
|
</a></h1>
|
|
<ul><li><a href="../inweb/index.html">inweb</a></li>
|
|
</ul><h2>Foundation Module</h2><ul>
|
|
<li><a href="index.html"><span class="selectedlink">foundation</span></a></li>
|
|
<li><a href="../foundation-test/index.html">foundation-test</a></li>
|
|
</ul><h2>Example Webs</h2><ul>
|
|
<li><a href="../goldbach/index.html">goldbach</a></li>
|
|
<li><a href="../twinprimes/twinprimes.html">twinprimes</a></li>
|
|
</ul><h2>External</h2><ul>
|
|
<li><a href="https://github.com/ganelson/inweb">github</a></li>
|
|
|
|
</ul>
|
|
</nav>
|
|
<main role="main">
|
|
|
|
<!--Weave of 'Binary Files' generated by 7-->
|
|
<ul class="crumbs"><li><a href="../index.html">Home</a></li><li><a href="index.html">foundation</a></li><li><a href="index.html#6">Chapter 6: Media</a></li><li><b>Binary Files</b></li></ul><p class="purpose">Routines for reading raw data from binary files.</p>
|
|
|
|
<ul class="toc"><li><a href="#SP1">§1. Reading binary data</a></li><li><a href="#SP7">§7. Size</a></li><li><a href="#SP8">§8. Opening</a></li><li><a href="#SP9">§9. Copying</a></li></ul><hr class="tocbar">
|
|
|
|
<p class="inwebparagraph"><a id="SP1"></a><b>§1. Reading binary data. </b>To begin with, integers of 8, 16, 32 and 64 bit widths respectively,
|
|
arranged with most significant byte (MSB) first.
|
|
</p>
|
|
|
|
<pre class="display">
|
|
<span class="reserved">int</span><span class="plain"> </span><span class="functiontext">BinaryFiles::read_int8<button class="popup" onclick="togglePopup('usagePopup444')">...<span class="popuptext" id="usagePopup444">Usage of <b>BinaryFiles::read_int8</b>:<br>Sound Durations - <a href="6-sd.html#SP2">§2</a>, <a href="6-sd.html#SP3">§3</a></span></button></span><span class="plain">(</span><span class="reserved">FILE</span><span class="plain"> *</span><span class="identifier">binary_file</span><span class="plain">, </span><span class="reserved">unsigned</span><span class="plain"> </span><span class="reserved">int</span><span class="plain"> *</span><span class="identifier">result</span><span class="plain">) {</span>
|
|
<span class="reserved">int</span><span class="plain"> </span><span class="identifier">c1</span><span class="plain"> = </span><span class="identifier">getc</span><span class="plain">(</span><span class="identifier">binary_file</span><span class="plain">);</span>
|
|
<span class="reserved">if</span><span class="plain"> (</span><span class="identifier">c1</span><span class="plain"> == </span><span class="identifier">EOF</span><span class="plain">) </span><span class="reserved">return</span><span class="plain"> </span><span class="constant">FALSE</span><span class="plain">;</span>
|
|
|
|
<span class="plain">*</span><span class="identifier">result</span><span class="plain"> = (</span><span class="reserved">unsigned</span><span class="plain"> </span><span class="reserved">int</span><span class="plain">) </span><span class="identifier">c1</span><span class="plain">;</span>
|
|
<span class="reserved">return</span><span class="plain"> </span><span class="constant">TRUE</span><span class="plain">;</span>
|
|
<span class="plain">}</span>
|
|
|
|
<span class="reserved">int</span><span class="plain"> </span><span class="functiontext">BinaryFiles::read_int16<button class="popup" onclick="togglePopup('usagePopup445')">...<span class="popuptext" id="usagePopup445">Usage of <b>BinaryFiles::read_int16</b>:<br>Image Dimensions - <a href="6-id.html#SP1">§1</a><br>Sound Durations - <a href="6-sd.html#SP1">§1</a>, <a href="6-sd.html#SP2">§2</a>, <a href="6-sd.html#SP3">§3</a></span></button></span><span class="plain">(</span><span class="reserved">FILE</span><span class="plain"> *</span><span class="identifier">binary_file</span><span class="plain">, </span><span class="reserved">unsigned</span><span class="plain"> </span><span class="reserved">int</span><span class="plain"> *</span><span class="identifier">result</span><span class="plain">) {</span>
|
|
<span class="reserved">int</span><span class="plain"> </span><span class="identifier">c1</span><span class="plain">, </span><span class="identifier">c2</span><span class="plain">;</span>
|
|
|
|
<span class="identifier">c1</span><span class="plain"> = </span><span class="identifier">getc</span><span class="plain">(</span><span class="identifier">binary_file</span><span class="plain">);</span>
|
|
<span class="identifier">c2</span><span class="plain"> = </span><span class="identifier">getc</span><span class="plain">(</span><span class="identifier">binary_file</span><span class="plain">);</span>
|
|
<span class="reserved">if</span><span class="plain"> (</span><span class="identifier">c1</span><span class="plain"> == </span><span class="identifier">EOF</span><span class="plain"> || </span><span class="identifier">c2</span><span class="plain"> == </span><span class="identifier">EOF</span><span class="plain">) </span><span class="reserved">return</span><span class="plain"> </span><span class="constant">FALSE</span><span class="plain">;</span>
|
|
|
|
<span class="plain">*</span><span class="identifier">result</span><span class="plain"> = (((</span><span class="reserved">unsigned</span><span class="plain"> </span><span class="reserved">int</span><span class="plain">) </span><span class="identifier">c1</span><span class="plain">) << </span><span class="constant">8</span><span class="plain">) + ((</span><span class="reserved">unsigned</span><span class="plain"> </span><span class="reserved">int</span><span class="plain">) </span><span class="identifier">c2</span><span class="plain">);</span>
|
|
<span class="reserved">return</span><span class="plain"> </span><span class="constant">TRUE</span><span class="plain">;</span>
|
|
<span class="plain">}</span>
|
|
|
|
<span class="reserved">int</span><span class="plain"> </span><span class="functiontext">BinaryFiles::read_int32<button class="popup" onclick="togglePopup('usagePopup446')">...<span class="popuptext" id="usagePopup446">Usage of <b>BinaryFiles::read_int32</b>:<br><a href="#SP5">§5</a>, Image Dimensions - <a href="6-id.html#SP2">§2</a><br>Sound Durations - <a href="6-sd.html#SP1">§1</a>, <a href="6-sd.html#SP2">§2</a>, <a href="6-sd.html#SP3">§3</a></span></button></span><span class="plain">(</span><span class="reserved">FILE</span><span class="plain"> *</span><span class="identifier">binary_file</span><span class="plain">, </span><span class="reserved">unsigned</span><span class="plain"> </span><span class="reserved">int</span><span class="plain"> *</span><span class="identifier">result</span><span class="plain">) {</span>
|
|
<span class="reserved">int</span><span class="plain"> </span><span class="identifier">c1</span><span class="plain">, </span><span class="identifier">c2</span><span class="plain">, </span><span class="identifier">c3</span><span class="plain">, </span><span class="identifier">c4</span><span class="plain">;</span>
|
|
|
|
<span class="identifier">c1</span><span class="plain"> = </span><span class="identifier">getc</span><span class="plain">(</span><span class="identifier">binary_file</span><span class="plain">);</span>
|
|
<span class="identifier">c2</span><span class="plain"> = </span><span class="identifier">getc</span><span class="plain">(</span><span class="identifier">binary_file</span><span class="plain">);</span>
|
|
<span class="identifier">c3</span><span class="plain"> = </span><span class="identifier">getc</span><span class="plain">(</span><span class="identifier">binary_file</span><span class="plain">);</span>
|
|
<span class="identifier">c4</span><span class="plain"> = </span><span class="identifier">getc</span><span class="plain">(</span><span class="identifier">binary_file</span><span class="plain">);</span>
|
|
<span class="reserved">if</span><span class="plain"> (</span><span class="identifier">c1</span><span class="plain"> == </span><span class="identifier">EOF</span><span class="plain"> || </span><span class="identifier">c2</span><span class="plain"> == </span><span class="identifier">EOF</span><span class="plain"> || </span><span class="identifier">c3</span><span class="plain"> == </span><span class="identifier">EOF</span><span class="plain"> || </span><span class="identifier">c4</span><span class="plain"> == </span><span class="identifier">EOF</span><span class="plain">) </span><span class="reserved">return</span><span class="plain"> </span><span class="constant">FALSE</span><span class="plain">;</span>
|
|
|
|
<span class="plain">*</span><span class="identifier">result</span><span class="plain"> = (((</span><span class="reserved">unsigned</span><span class="plain"> </span><span class="reserved">int</span><span class="plain">) </span><span class="identifier">c1</span><span class="plain">) << </span><span class="constant">24</span><span class="plain">) +</span>
|
|
<span class="plain">(((</span><span class="reserved">unsigned</span><span class="plain"> </span><span class="reserved">int</span><span class="plain">) </span><span class="identifier">c2</span><span class="plain">) << </span><span class="constant">16</span><span class="plain">) +</span>
|
|
<span class="plain">(((</span><span class="reserved">unsigned</span><span class="plain"> </span><span class="reserved">int</span><span class="plain">) </span><span class="identifier">c3</span><span class="plain">) << </span><span class="constant">8</span><span class="plain">) + ((</span><span class="reserved">unsigned</span><span class="plain"> </span><span class="reserved">int</span><span class="plain">) </span><span class="identifier">c4</span><span class="plain">);</span>
|
|
<span class="reserved">return</span><span class="plain"> </span><span class="constant">TRUE</span><span class="plain">;</span>
|
|
<span class="plain">}</span>
|
|
|
|
<span class="reserved">int</span><span class="plain"> </span><span class="functiontext">BinaryFiles::read_int64<button class="popup" onclick="togglePopup('usagePopup447')">...<span class="popuptext" id="usagePopup447">Usage of <b>BinaryFiles::read_int64</b>:<br>Sound Durations - <a href="6-sd.html#SP2">§2</a></span></button></span><span class="plain">(</span><span class="reserved">FILE</span><span class="plain"> *</span><span class="identifier">binary_file</span><span class="plain">, </span><span class="reserved">unsigned</span><span class="plain"> </span><span class="reserved">long</span><span class="plain"> </span><span class="reserved">long</span><span class="plain"> *</span><span class="identifier">result</span><span class="plain">) {</span>
|
|
<span class="reserved">int</span><span class="plain"> </span><span class="identifier">c1</span><span class="plain">, </span><span class="identifier">c2</span><span class="plain">, </span><span class="identifier">c3</span><span class="plain">, </span><span class="identifier">c4</span><span class="plain">, </span><span class="identifier">c5</span><span class="plain">, </span><span class="identifier">c6</span><span class="plain">, </span><span class="identifier">c7</span><span class="plain">, </span><span class="identifier">c8</span><span class="plain">;</span>
|
|
|
|
<span class="identifier">c1</span><span class="plain"> = </span><span class="identifier">getc</span><span class="plain">(</span><span class="identifier">binary_file</span><span class="plain">);</span>
|
|
<span class="identifier">c2</span><span class="plain"> = </span><span class="identifier">getc</span><span class="plain">(</span><span class="identifier">binary_file</span><span class="plain">);</span>
|
|
<span class="identifier">c3</span><span class="plain"> = </span><span class="identifier">getc</span><span class="plain">(</span><span class="identifier">binary_file</span><span class="plain">);</span>
|
|
<span class="identifier">c4</span><span class="plain"> = </span><span class="identifier">getc</span><span class="plain">(</span><span class="identifier">binary_file</span><span class="plain">);</span>
|
|
<span class="identifier">c5</span><span class="plain"> = </span><span class="identifier">getc</span><span class="plain">(</span><span class="identifier">binary_file</span><span class="plain">);</span>
|
|
<span class="identifier">c6</span><span class="plain"> = </span><span class="identifier">getc</span><span class="plain">(</span><span class="identifier">binary_file</span><span class="plain">);</span>
|
|
<span class="identifier">c7</span><span class="plain"> = </span><span class="identifier">getc</span><span class="plain">(</span><span class="identifier">binary_file</span><span class="plain">);</span>
|
|
<span class="identifier">c8</span><span class="plain"> = </span><span class="identifier">getc</span><span class="plain">(</span><span class="identifier">binary_file</span><span class="plain">);</span>
|
|
<span class="reserved">if</span><span class="plain"> (</span><span class="identifier">c1</span><span class="plain"> == </span><span class="identifier">EOF</span><span class="plain"> || </span><span class="identifier">c2</span><span class="plain"> == </span><span class="identifier">EOF</span><span class="plain"> || </span><span class="identifier">c3</span><span class="plain"> == </span><span class="identifier">EOF</span><span class="plain"> || </span><span class="identifier">c4</span><span class="plain"> == </span><span class="identifier">EOF</span><span class="plain"> || </span><span class="identifier">c5</span><span class="plain"> == </span><span class="identifier">EOF</span>
|
|
<span class="plain">|| </span><span class="identifier">c6</span><span class="plain"> == </span><span class="identifier">EOF</span><span class="plain"> || </span><span class="identifier">c7</span><span class="plain"> == </span><span class="identifier">EOF</span><span class="plain"> || </span><span class="identifier">c8</span><span class="plain"> == </span><span class="identifier">EOF</span><span class="plain">) </span><span class="reserved">return</span><span class="plain"> </span><span class="constant">FALSE</span><span class="plain">;</span>
|
|
|
|
<span class="plain">*</span><span class="identifier">result</span><span class="plain"> = (((</span><span class="reserved">unsigned</span><span class="plain"> </span><span class="reserved">long</span><span class="plain"> </span><span class="reserved">long</span><span class="plain">) </span><span class="identifier">c1</span><span class="plain">) << </span><span class="constant">56</span><span class="plain">) +</span>
|
|
<span class="plain"> (((</span><span class="reserved">unsigned</span><span class="plain"> </span><span class="reserved">long</span><span class="plain"> </span><span class="reserved">long</span><span class="plain">) </span><span class="identifier">c2</span><span class="plain">) << </span><span class="constant">48</span><span class="plain">) +</span>
|
|
<span class="plain"> (((</span><span class="reserved">unsigned</span><span class="plain"> </span><span class="reserved">long</span><span class="plain"> </span><span class="reserved">long</span><span class="plain">) </span><span class="identifier">c3</span><span class="plain">) << </span><span class="constant">40</span><span class="plain">) +</span>
|
|
<span class="plain"> (((</span><span class="reserved">unsigned</span><span class="plain"> </span><span class="reserved">long</span><span class="plain"> </span><span class="reserved">long</span><span class="plain">) </span><span class="identifier">c4</span><span class="plain">) << </span><span class="constant">32</span><span class="plain">) +</span>
|
|
<span class="plain"> (((</span><span class="reserved">unsigned</span><span class="plain"> </span><span class="reserved">long</span><span class="plain"> </span><span class="reserved">long</span><span class="plain">) </span><span class="identifier">c5</span><span class="plain">) << </span><span class="constant">24</span><span class="plain">) +</span>
|
|
<span class="plain"> (((</span><span class="reserved">unsigned</span><span class="plain"> </span><span class="reserved">long</span><span class="plain"> </span><span class="reserved">long</span><span class="plain">) </span><span class="identifier">c6</span><span class="plain">) << </span><span class="constant">16</span><span class="plain">) +</span>
|
|
<span class="plain"> (((</span><span class="reserved">unsigned</span><span class="plain"> </span><span class="reserved">long</span><span class="plain"> </span><span class="reserved">long</span><span class="plain">) </span><span class="identifier">c7</span><span class="plain">) << </span><span class="constant">8</span><span class="plain">) +</span>
|
|
<span class="plain">((</span><span class="reserved">unsigned</span><span class="plain"> </span><span class="reserved">long</span><span class="plain"> </span><span class="reserved">long</span><span class="plain">) </span><span class="identifier">c8</span><span class="plain">);</span>
|
|
<span class="reserved">return</span><span class="plain"> </span><span class="constant">TRUE</span><span class="plain">;</span>
|
|
<span class="plain">}</span>
|
|
</pre>
|
|
|
|
<p class="inwebparagraph"></p>
|
|
|
|
<p class="inwebparagraph"><a id="SP2"></a><b>§2. </b></p>
|
|
|
|
<pre class="display">
|
|
<span class="reserved">int</span><span class="plain"> </span><span class="functiontext">BinaryFiles::write_int32<button class="popup" onclick="togglePopup('usagePopup448')">...<span class="popuptext" id="usagePopup448">Usage of <b>BinaryFiles::write_int32</b>:<br>none</span></button></span><span class="plain">(</span><span class="reserved">FILE</span><span class="plain"> *</span><span class="identifier">binary_file</span><span class="plain">, </span><span class="reserved">unsigned</span><span class="plain"> </span><span class="reserved">int</span><span class="plain"> </span><span class="identifier">val</span><span class="plain">) {</span>
|
|
<span class="reserved">int</span><span class="plain"> </span><span class="identifier">c1</span><span class="plain"> = (</span><span class="reserved">int</span><span class="plain">) ((</span><span class="identifier">val</span><span class="plain"> >> </span><span class="constant">24</span><span class="plain">) & </span><span class="constant">0xFF</span><span class="plain">);</span>
|
|
<span class="reserved">int</span><span class="plain"> </span><span class="identifier">c2</span><span class="plain"> = (</span><span class="reserved">int</span><span class="plain">) ((</span><span class="identifier">val</span><span class="plain"> >> </span><span class="constant">16</span><span class="plain">) & </span><span class="constant">0xFF</span><span class="plain">);</span>
|
|
<span class="reserved">int</span><span class="plain"> </span><span class="identifier">c3</span><span class="plain"> = (</span><span class="reserved">int</span><span class="plain">) ((</span><span class="identifier">val</span><span class="plain"> >> </span><span class="constant">8</span><span class="plain">) & </span><span class="constant">0xFF</span><span class="plain">);</span>
|
|
<span class="reserved">int</span><span class="plain"> </span><span class="identifier">c4</span><span class="plain"> = (</span><span class="reserved">int</span><span class="plain">) (</span><span class="identifier">val</span><span class="plain"> & </span><span class="constant">0xFF</span><span class="plain">);</span>
|
|
<span class="reserved">if</span><span class="plain"> (</span><span class="identifier">putc</span><span class="plain">(</span><span class="identifier">c1</span><span class="plain">, </span><span class="identifier">binary_file</span><span class="plain">) == </span><span class="identifier">EOF</span><span class="plain">) </span><span class="reserved">return</span><span class="plain"> </span><span class="constant">FALSE</span><span class="plain">;</span>
|
|
<span class="reserved">if</span><span class="plain"> (</span><span class="identifier">putc</span><span class="plain">(</span><span class="identifier">c2</span><span class="plain">, </span><span class="identifier">binary_file</span><span class="plain">) == </span><span class="identifier">EOF</span><span class="plain">) </span><span class="reserved">return</span><span class="plain"> </span><span class="constant">FALSE</span><span class="plain">;</span>
|
|
<span class="reserved">if</span><span class="plain"> (</span><span class="identifier">putc</span><span class="plain">(</span><span class="identifier">c3</span><span class="plain">, </span><span class="identifier">binary_file</span><span class="plain">) == </span><span class="identifier">EOF</span><span class="plain">) </span><span class="reserved">return</span><span class="plain"> </span><span class="constant">FALSE</span><span class="plain">;</span>
|
|
<span class="reserved">if</span><span class="plain"> (</span><span class="identifier">putc</span><span class="plain">(</span><span class="identifier">c4</span><span class="plain">, </span><span class="identifier">binary_file</span><span class="plain">) == </span><span class="identifier">EOF</span><span class="plain">) </span><span class="reserved">return</span><span class="plain"> </span><span class="constant">FALSE</span><span class="plain">;</span>
|
|
|
|
<span class="reserved">return</span><span class="plain"> </span><span class="constant">TRUE</span><span class="plain">;</span>
|
|
<span class="plain">}</span>
|
|
</pre>
|
|
|
|
<p class="inwebparagraph"></p>
|
|
|
|
<p class="inwebparagraph"><a id="SP3"></a><b>§3. </b>We will sometimes need to toggle between MSB and LSB representation of
|
|
integers 32 or 64 bits wide:
|
|
</p>
|
|
|
|
<pre class="display">
|
|
<span class="reserved">void</span><span class="plain"> </span><span class="functiontext">BinaryFiles::swap_bytes32<button class="popup" onclick="togglePopup('usagePopup449')">...<span class="popuptext" id="usagePopup449">Usage of <b>BinaryFiles::swap_bytes32</b>:<br>Sound Durations - <a href="6-sd.html#SP2">§2</a></span></button></span><span class="plain">(</span><span class="reserved">unsigned</span><span class="plain"> </span><span class="reserved">int</span><span class="plain"> *</span><span class="identifier">value</span><span class="plain">) {</span>
|
|
<span class="reserved">unsigned</span><span class="plain"> </span><span class="reserved">int</span><span class="plain"> </span><span class="identifier">result</span><span class="plain"> = (((*</span><span class="identifier">value</span><span class="plain"> & </span><span class="constant">0xff</span><span class="plain">) << </span><span class="constant">24</span><span class="plain">) +</span>
|
|
<span class="plain">((*</span><span class="identifier">value</span><span class="plain"> & </span><span class="constant">0xff00</span><span class="plain">) << </span><span class="constant">8</span><span class="plain">) +</span>
|
|
<span class="plain">((*</span><span class="identifier">value</span><span class="plain"> & </span><span class="constant">0xff0000</span><span class="plain">) >> </span><span class="constant">8</span><span class="plain">) +</span>
|
|
<span class="plain">((*</span><span class="identifier">value</span><span class="plain"> & </span><span class="constant">0xff000000</span><span class="plain">) >> </span><span class="constant">24</span><span class="plain"> ) );</span>
|
|
<span class="plain">*</span><span class="identifier">value</span><span class="plain"> = </span><span class="identifier">result</span><span class="plain">;</span>
|
|
<span class="plain">}</span>
|
|
|
|
<span class="reserved">void</span><span class="plain"> </span><span class="functiontext">BinaryFiles::swap_bytes64<button class="popup" onclick="togglePopup('usagePopup450')">...<span class="popuptext" id="usagePopup450">Usage of <b>BinaryFiles::swap_bytes64</b>:<br>Sound Durations - <a href="6-sd.html#SP2">§2</a></span></button></span><span class="plain">(</span><span class="reserved">unsigned</span><span class="plain"> </span><span class="reserved">long</span><span class="plain"> </span><span class="reserved">long</span><span class="plain"> *</span><span class="identifier">value</span><span class="plain">) {</span>
|
|
<span class="reserved">unsigned</span><span class="plain"> </span><span class="reserved">long</span><span class="plain"> </span><span class="reserved">long</span><span class="plain"> </span><span class="identifier">result</span><span class="plain"> = (((*</span><span class="identifier">value</span><span class="plain"> & </span><span class="constant">0xff</span><span class="plain">) << </span><span class="constant">56</span><span class="plain">) +</span>
|
|
<span class="plain"> ((*</span><span class="identifier">value</span><span class="plain"> & </span><span class="constant">0xff00</span><span class="plain">) << </span><span class="constant">40</span><span class="plain">) +</span>
|
|
<span class="plain"> ((*</span><span class="identifier">value</span><span class="plain"> & </span><span class="constant">0xff0000</span><span class="plain">) << </span><span class="constant">24</span><span class="plain">) +</span>
|
|
<span class="plain"> ((*</span><span class="identifier">value</span><span class="plain"> & </span><span class="constant">0xff000000</span><span class="plain">) << </span><span class="constant">8</span><span class="plain">) +</span>
|
|
<span class="plain"> ((*</span><span class="identifier">value</span><span class="plain"> >> </span><span class="constant">8</span><span class="plain">) & </span><span class="constant">0xff000000</span><span class="plain">) +</span>
|
|
<span class="plain"> ((*</span><span class="identifier">value</span><span class="plain"> >> </span><span class="constant">24</span><span class="plain">) & </span><span class="constant">0xff0000</span><span class="plain">) +</span>
|
|
<span class="plain"> ((*</span><span class="identifier">value</span><span class="plain"> >> </span><span class="constant">40</span><span class="plain">) & </span><span class="constant">0xff00</span><span class="plain">) +</span>
|
|
<span class="plain"> ((*</span><span class="identifier">value</span><span class="plain"> >> </span><span class="constant">56</span><span class="plain">) & </span><span class="constant">0xff</span><span class="plain">) );</span>
|
|
<span class="plain">*</span><span class="identifier">value</span><span class="plain"> = </span><span class="identifier">result</span><span class="plain">;</span>
|
|
<span class="plain">}</span>
|
|
</pre>
|
|
|
|
<p class="inwebparagraph"></p>
|
|
|
|
<p class="inwebparagraph"><a id="SP4"></a><b>§4. </b>Some file formats also have variable-sized integers, as a sequence of
|
|
bytes (most significant first) in which each byte consists of seven bits
|
|
of data plus a most significant bit which marks that a continuation byte
|
|
follows:
|
|
</p>
|
|
|
|
<pre class="display">
|
|
<span class="reserved">int</span><span class="plain"> </span><span class="functiontext">BinaryFiles::read_variable_length_integer<button class="popup" onclick="togglePopup('usagePopup451')">...<span class="popuptext" id="usagePopup451">Usage of <b>BinaryFiles::read_variable_length_integer</b>:<br>Sound Durations - <a href="6-sd.html#SP3">§3</a></span></button></span><span class="plain">(</span><span class="reserved">FILE</span><span class="plain"> *</span><span class="identifier">binary_file</span><span class="plain">, </span><span class="reserved">unsigned</span><span class="plain"> </span><span class="reserved">int</span><span class="plain"> *</span><span class="identifier">result</span><span class="plain">) {</span>
|
|
<span class="reserved">int</span><span class="plain"> </span><span class="identifier">c</span><span class="plain">;</span>
|
|
|
|
<span class="plain">*</span><span class="identifier">result</span><span class="plain"> = </span><span class="constant">0</span><span class="plain">;</span>
|
|
<span class="reserved">do</span><span class="plain"> {</span>
|
|
<span class="identifier">c</span><span class="plain"> = </span><span class="identifier">getc</span><span class="plain">(</span><span class="identifier">binary_file</span><span class="plain">);</span>
|
|
<span class="reserved">if</span><span class="plain"> (</span><span class="identifier">c</span><span class="plain"> == </span><span class="identifier">EOF</span><span class="plain">) </span><span class="reserved">return</span><span class="plain"> </span><span class="constant">FALSE</span><span class="plain">;</span>
|
|
<span class="plain">*</span><span class="identifier">result</span><span class="plain"> = (*</span><span class="identifier">result</span><span class="plain"> << </span><span class="constant">7</span><span class="plain">) + (((</span><span class="reserved">unsigned</span><span class="plain"> </span><span class="reserved">char</span><span class="plain">) </span><span class="identifier">c</span><span class="plain">) & </span><span class="constant">0x7F</span><span class="plain">);</span>
|
|
<span class="plain">} </span><span class="reserved">while</span><span class="plain"> (((</span><span class="reserved">unsigned</span><span class="plain"> </span><span class="reserved">char</span><span class="plain">) </span><span class="identifier">c</span><span class="plain">) & </span><span class="constant">0x80</span><span class="plain">);</span>
|
|
|
|
<span class="reserved">return</span><span class="plain"> </span><span class="constant">TRUE</span><span class="plain">;</span>
|
|
<span class="plain">}</span>
|
|
</pre>
|
|
|
|
<p class="inwebparagraph"></p>
|
|
|
|
<p class="inwebparagraph"><a id="SP5"></a><b>§5. </b>Here we read just the mantissa of a particular representation of
|
|
floating-point numbers:
|
|
</p>
|
|
|
|
<pre class="display">
|
|
<span class="reserved">int</span><span class="plain"> </span><span class="functiontext">BinaryFiles::read_float80<button class="popup" onclick="togglePopup('usagePopup452')">...<span class="popuptext" id="usagePopup452">Usage of <b>BinaryFiles::read_float80</b>:<br>Sound Durations - <a href="6-sd.html#SP1">§1</a></span></button></span><span class="plain">(</span><span class="reserved">FILE</span><span class="plain"> *</span><span class="identifier">binary_file</span><span class="plain">, </span><span class="reserved">unsigned</span><span class="plain"> </span><span class="reserved">int</span><span class="plain"> *</span><span class="identifier">result</span><span class="plain">) {</span>
|
|
<span class="reserved">int</span><span class="plain"> </span><span class="identifier">c1</span><span class="plain">, </span><span class="identifier">c2</span><span class="plain">, </span><span class="identifier">exp</span><span class="plain">;</span>
|
|
<span class="reserved">unsigned</span><span class="plain"> </span><span class="reserved">int</span><span class="plain"> </span><span class="identifier">prev</span><span class="plain"> = </span><span class="constant">0</span><span class="plain">, </span><span class="identifier">mantissa</span><span class="plain">;</span>
|
|
|
|
<span class="identifier">c1</span><span class="plain"> = </span><span class="identifier">getc</span><span class="plain">(</span><span class="identifier">binary_file</span><span class="plain">);</span>
|
|
<span class="identifier">c2</span><span class="plain"> = </span><span class="identifier">getc</span><span class="plain">(</span><span class="identifier">binary_file</span><span class="plain">);</span>
|
|
<span class="reserved">if</span><span class="plain"> (</span><span class="identifier">c1</span><span class="plain"> == </span><span class="identifier">EOF</span><span class="plain"> || </span><span class="identifier">c2</span><span class="plain"> == </span><span class="identifier">EOF</span><span class="plain">) </span><span class="reserved">return</span><span class="plain"> </span><span class="constant">FALSE</span><span class="plain">;</span>
|
|
<span class="reserved">if</span><span class="plain"> (!</span><span class="functiontext"><a href="#SP1">BinaryFiles::read_int32</a></span><span class="plain">(</span><span class="identifier">binary_file</span><span class="plain">, &</span><span class="identifier">mantissa</span><span class="plain">)) </span><span class="reserved">return</span><span class="plain"> </span><span class="constant">FALSE</span><span class="plain">;</span>
|
|
|
|
<span class="identifier">exp</span><span class="plain"> = </span><span class="constant">30</span><span class="plain"> - </span><span class="identifier">c2</span><span class="plain">;</span>
|
|
<span class="reserved">while</span><span class="plain"> (</span><span class="identifier">exp</span><span class="plain">--) {</span>
|
|
<span class="identifier">prev</span><span class="plain"> = </span><span class="identifier">mantissa</span><span class="plain">;</span>
|
|
<span class="identifier">mantissa</span><span class="plain"> >>= </span><span class="constant">1</span><span class="plain">;</span>
|
|
<span class="plain">}</span>
|
|
<span class="reserved">if</span><span class="plain"> (</span><span class="identifier">prev</span><span class="plain"> & </span><span class="constant">1</span><span class="plain">) </span><span class="identifier">mantissa</span><span class="plain">++;</span>
|
|
|
|
<span class="plain">*</span><span class="identifier">result</span><span class="plain"> = (</span><span class="reserved">unsigned</span><span class="plain"> </span><span class="reserved">int</span><span class="plain">) </span><span class="identifier">mantissa</span><span class="plain">;</span>
|
|
<span class="reserved">return</span><span class="plain"> </span><span class="constant">TRUE</span><span class="plain">;</span>
|
|
<span class="plain">}</span>
|
|
</pre>
|
|
|
|
<p class="inwebparagraph"></p>
|
|
|
|
<p class="inwebparagraph"><a id="SP6"></a><b>§6. </b>And lastly we read a string of a supplied length from the file, and
|
|
then null terminate it to make it valid C string. (<code class="display"><span class="extract">string</span></code> must therefore
|
|
be at least <code class="display"><span class="extract">length</span></code> plus 1 bytes long.)
|
|
</p>
|
|
|
|
<pre class="display">
|
|
<span class="reserved">int</span><span class="plain"> </span><span class="functiontext">BinaryFiles::read_string<button class="popup" onclick="togglePopup('usagePopup453')">...<span class="popuptext" id="usagePopup453">Usage of <b>BinaryFiles::read_string</b>:<br>Sound Durations - <a href="6-sd.html#SP3">§3</a></span></button></span><span class="plain">(</span><span class="reserved">FILE</span><span class="plain"> *</span><span class="identifier">binary_file</span><span class="plain">, </span><span class="reserved">char</span><span class="plain"> *</span><span class="identifier">string</span><span class="plain">, </span><span class="reserved">unsigned</span><span class="plain"> </span><span class="reserved">int</span><span class="plain"> </span><span class="identifier">length</span><span class="plain">) {</span>
|
|
<span class="reserved">if</span><span class="plain"> (</span><span class="identifier">length</span><span class="plain"> > </span><span class="constant">0</span><span class="plain">) {</span>
|
|
<span class="reserved">if</span><span class="plain"> (</span><span class="identifier">fread</span><span class="plain">(</span><span class="identifier">string</span><span class="plain">, </span><span class="constant">1</span><span class="plain">, </span><span class="identifier">length</span><span class="plain">, </span><span class="identifier">binary_file</span><span class="plain">) != </span><span class="identifier">length</span><span class="plain">) </span><span class="reserved">return</span><span class="plain"> </span><span class="constant">FALSE</span><span class="plain">;</span>
|
|
<span class="plain">}</span>
|
|
<span class="identifier">string</span><span class="plain">[</span><span class="identifier">length</span><span class="plain">] = </span><span class="constant">0</span><span class="plain">;</span>
|
|
|
|
<span class="reserved">return</span><span class="plain"> </span><span class="constant">TRUE</span><span class="plain">;</span>
|
|
<span class="plain">}</span>
|
|
</pre>
|
|
|
|
<p class="inwebparagraph"></p>
|
|
|
|
<p class="inwebparagraph"><a id="SP7"></a><b>§7. Size. </b></p>
|
|
|
|
<pre class="display">
|
|
<span class="reserved">long</span><span class="plain"> </span><span class="reserved">int</span><span class="plain"> </span><span class="functiontext">BinaryFiles::size<button class="popup" onclick="togglePopup('usagePopup454')">...<span class="popuptext" id="usagePopup454">Usage of <b>BinaryFiles::size</b>:<br>none</span></button></span><span class="plain">(</span><span class="reserved">filename</span><span class="plain"> *</span><span class="identifier">F</span><span class="plain">) {</span>
|
|
<span class="reserved">FILE</span><span class="plain"> *</span><span class="identifier">TEST_FILE</span><span class="plain"> = </span><span class="functiontext"><a href="#SP8">BinaryFiles::try_to_open_for_reading</a></span><span class="plain">(</span><span class="identifier">F</span><span class="plain">);</span>
|
|
<span class="reserved">if</span><span class="plain"> (</span><span class="identifier">TEST_FILE</span><span class="plain">) {</span>
|
|
<span class="reserved">if</span><span class="plain"> (</span><span class="identifier">fseek</span><span class="plain">(</span><span class="identifier">TEST_FILE</span><span class="plain">, </span><span class="constant">0</span><span class="plain">, </span><span class="identifier">SEEK_END</span><span class="plain">) == </span><span class="constant">0</span><span class="plain">) {</span>
|
|
<span class="reserved">long</span><span class="plain"> </span><span class="reserved">int</span><span class="plain"> </span><span class="identifier">file_size</span><span class="plain"> = </span><span class="identifier">ftell</span><span class="plain">(</span><span class="identifier">TEST_FILE</span><span class="plain">);</span>
|
|
<span class="reserved">if</span><span class="plain"> (</span><span class="identifier">file_size</span><span class="plain"> == -1</span><span class="identifier">L</span><span class="plain">) </span><span class="functiontext"><a href="3-em.html#SP2">Errors::fatal_with_file</a></span><span class="plain">(</span><span class="string">"ftell failed on linked file"</span><span class="plain">, </span><span class="identifier">F</span><span class="plain">);</span>
|
|
<span class="functiontext"><a href="#SP8">BinaryFiles::close</a></span><span class="plain">(</span><span class="identifier">TEST_FILE</span><span class="plain">);</span>
|
|
<span class="reserved">return</span><span class="plain"> </span><span class="identifier">file_size</span><span class="plain">;</span>
|
|
<span class="plain">} </span><span class="reserved">else</span><span class="plain"> </span><span class="functiontext"><a href="3-em.html#SP2">Errors::fatal_with_file</a></span><span class="plain">(</span><span class="string">"fseek failed on linked file"</span><span class="plain">, </span><span class="identifier">F</span><span class="plain">);</span>
|
|
<span class="functiontext"><a href="#SP8">BinaryFiles::close</a></span><span class="plain">(</span><span class="identifier">TEST_FILE</span><span class="plain">);</span>
|
|
<span class="plain">}</span>
|
|
<span class="reserved">return</span><span class="plain"> -1</span><span class="identifier">L</span><span class="plain">;</span>
|
|
<span class="plain">}</span>
|
|
</pre>
|
|
|
|
<p class="inwebparagraph"></p>
|
|
|
|
<p class="inwebparagraph"><a id="SP8"></a><b>§8. Opening. </b></p>
|
|
|
|
<pre class="display">
|
|
<span class="reserved">FILE</span><span class="plain"> *</span><span class="functiontext">BinaryFiles::open_for_reading<button class="popup" onclick="togglePopup('usagePopup455')">...<span class="popuptext" id="usagePopup455">Usage of <b>BinaryFiles::open_for_reading</b>:<br>none</span></button></span><span class="plain">(</span><span class="reserved">filename</span><span class="plain"> *</span><span class="identifier">F</span><span class="plain">) {</span>
|
|
<span class="reserved">FILE</span><span class="plain"> *</span><span class="identifier">handle</span><span class="plain"> = </span><span class="functiontext"><a href="3-fln.html#SP10">Filenames::fopen</a></span><span class="plain">(</span><span class="identifier">F</span><span class="plain">, </span><span class="string">"rb"</span><span class="plain">);</span>
|
|
<span class="reserved">if</span><span class="plain"> (</span><span class="identifier">handle</span><span class="plain"> == </span><span class="identifier">NULL</span><span class="plain">) </span><span class="functiontext"><a href="3-em.html#SP2">Errors::fatal_with_file</a></span><span class="plain">(</span><span class="string">"unable to read file"</span><span class="plain">, </span><span class="identifier">F</span><span class="plain">);</span>
|
|
<span class="reserved">return</span><span class="plain"> </span><span class="identifier">handle</span><span class="plain">;</span>
|
|
<span class="plain">}</span>
|
|
|
|
<span class="reserved">FILE</span><span class="plain"> *</span><span class="functiontext">BinaryFiles::try_to_open_for_reading<button class="popup" onclick="togglePopup('usagePopup456')">...<span class="popuptext" id="usagePopup456">Usage of <b>BinaryFiles::try_to_open_for_reading</b>:<br><a href="#SP7">§7</a>, <a href="#SP9">§9</a></span></button></span><span class="plain">(</span><span class="reserved">filename</span><span class="plain"> *</span><span class="identifier">F</span><span class="plain">) {</span>
|
|
<span class="reserved">return</span><span class="plain"> </span><span class="functiontext"><a href="3-fln.html#SP10">Filenames::fopen</a></span><span class="plain">(</span><span class="identifier">F</span><span class="plain">, </span><span class="string">"rb"</span><span class="plain">);</span>
|
|
<span class="plain">}</span>
|
|
|
|
<span class="reserved">FILE</span><span class="plain"> *</span><span class="functiontext">BinaryFiles::open_for_writing<button class="popup" onclick="togglePopup('usagePopup457')">...<span class="popuptext" id="usagePopup457">Usage of <b>BinaryFiles::open_for_writing</b>:<br>none</span></button></span><span class="plain">(</span><span class="reserved">filename</span><span class="plain"> *</span><span class="identifier">F</span><span class="plain">) {</span>
|
|
<span class="reserved">FILE</span><span class="plain"> *</span><span class="identifier">handle</span><span class="plain"> = </span><span class="functiontext"><a href="3-fln.html#SP10">Filenames::fopen</a></span><span class="plain">(</span><span class="identifier">F</span><span class="plain">, </span><span class="string">"wb"</span><span class="plain">);</span>
|
|
<span class="reserved">if</span><span class="plain"> (</span><span class="identifier">handle</span><span class="plain"> == </span><span class="identifier">NULL</span><span class="plain">) </span><span class="functiontext"><a href="3-em.html#SP2">Errors::fatal_with_file</a></span><span class="plain">(</span><span class="string">"unable to write file"</span><span class="plain">, </span><span class="identifier">F</span><span class="plain">);</span>
|
|
<span class="reserved">return</span><span class="plain"> </span><span class="identifier">handle</span><span class="plain">;</span>
|
|
<span class="plain">}</span>
|
|
|
|
<span class="reserved">FILE</span><span class="plain"> *</span><span class="functiontext">BinaryFiles::try_to_open_for_writing<button class="popup" onclick="togglePopup('usagePopup458')">...<span class="popuptext" id="usagePopup458">Usage of <b>BinaryFiles::try_to_open_for_writing</b>:<br><a href="#SP9">§9</a></span></button></span><span class="plain">(</span><span class="reserved">filename</span><span class="plain"> *</span><span class="identifier">F</span><span class="plain">) {</span>
|
|
<span class="reserved">return</span><span class="plain"> </span><span class="functiontext"><a href="3-fln.html#SP10">Filenames::fopen</a></span><span class="plain">(</span><span class="identifier">F</span><span class="plain">, </span><span class="string">"wb"</span><span class="plain">);</span>
|
|
<span class="plain">}</span>
|
|
|
|
<span class="reserved">void</span><span class="plain"> </span><span class="functiontext">BinaryFiles::close<button class="popup" onclick="togglePopup('usagePopup459')">...<span class="popuptext" id="usagePopup459">Usage of <b>BinaryFiles::close</b>:<br><a href="#SP7">§7</a>, <a href="#SP9">§9</a></span></button></span><span class="plain">(</span><span class="reserved">FILE</span><span class="plain"> *</span><span class="identifier">handle</span><span class="plain">) {</span>
|
|
<span class="identifier">fclose</span><span class="plain">(</span><span class="identifier">handle</span><span class="plain">);</span>
|
|
<span class="plain">}</span>
|
|
</pre>
|
|
|
|
<p class="inwebparagraph"></p>
|
|
|
|
<p class="inwebparagraph"><a id="SP9"></a><b>§9. Copying. </b>This achieves a binary copy of a file when we haven't got access to the shell,
|
|
or to system APIs.
|
|
</p>
|
|
|
|
<pre class="display">
|
|
<span class="reserved">int</span><span class="plain"> </span><span class="functiontext">BinaryFiles::copy<button class="popup" onclick="togglePopup('usagePopup460')">...<span class="popuptext" id="usagePopup460">Usage of <b>BinaryFiles::copy</b>:<br>none</span></button></span><span class="plain">(</span><span class="reserved">filename</span><span class="plain"> *</span><span class="identifier">from</span><span class="plain">, </span><span class="reserved">filename</span><span class="plain"> *</span><span class="identifier">to</span><span class="plain">, </span><span class="reserved">int</span><span class="plain"> </span><span class="identifier">suppress_error</span><span class="plain">) {</span>
|
|
<span class="reserved">if</span><span class="plain"> ((</span><span class="identifier">from</span><span class="plain"> == </span><span class="identifier">NULL</span><span class="plain">) || (</span><span class="identifier">to</span><span class="plain"> == </span><span class="identifier">NULL</span><span class="plain">))</span>
|
|
<span class="functiontext"><a href="3-em.html#SP2">Errors::fatal</a></span><span class="plain">(</span><span class="string">"files confused in copier"</span><span class="plain">);</span>
|
|
|
|
<span class="reserved">FILE</span><span class="plain"> *</span><span class="identifier">FROM</span><span class="plain"> = </span><span class="functiontext"><a href="#SP8">BinaryFiles::try_to_open_for_reading</a></span><span class="plain">(</span><span class="identifier">from</span><span class="plain">);</span>
|
|
<span class="reserved">if</span><span class="plain"> (</span><span class="identifier">FROM</span><span class="plain"> == </span><span class="identifier">NULL</span><span class="plain">) {</span>
|
|
<span class="reserved">if</span><span class="plain"> (</span><span class="identifier">suppress_error</span><span class="plain"> == </span><span class="constant">FALSE</span><span class="plain">) </span><span class="functiontext"><a href="3-em.html#SP2">Errors::fatal_with_file</a></span><span class="plain">(</span><span class="string">"unable to read file"</span><span class="plain">, </span><span class="identifier">from</span><span class="plain">);</span>
|
|
<span class="reserved">return</span><span class="plain"> -1;</span>
|
|
<span class="plain">}</span>
|
|
<span class="reserved">FILE</span><span class="plain"> *</span><span class="identifier">TO</span><span class="plain"> = </span><span class="functiontext"><a href="#SP8">BinaryFiles::try_to_open_for_writing</a></span><span class="plain">(</span><span class="identifier">to</span><span class="plain">);</span>
|
|
<span class="reserved">if</span><span class="plain"> (</span><span class="identifier">TO</span><span class="plain"> == </span><span class="identifier">NULL</span><span class="plain">) {</span>
|
|
<span class="reserved">if</span><span class="plain"> (</span><span class="identifier">suppress_error</span><span class="plain"> == </span><span class="constant">FALSE</span><span class="plain">) </span><span class="functiontext"><a href="3-em.html#SP2">Errors::fatal_with_file</a></span><span class="plain">(</span><span class="string">"unable to write to file"</span><span class="plain">, </span><span class="identifier">to</span><span class="plain">);</span>
|
|
<span class="reserved">return</span><span class="plain"> -1;</span>
|
|
<span class="plain">}</span>
|
|
|
|
<span class="reserved">int</span><span class="plain"> </span><span class="identifier">size</span><span class="plain"> = </span><span class="constant">0</span><span class="plain">;</span>
|
|
<span class="reserved">while</span><span class="plain"> (</span><span class="constant">TRUE</span><span class="plain">) {</span>
|
|
<span class="reserved">int</span><span class="plain"> </span><span class="identifier">c</span><span class="plain"> = </span><span class="identifier">fgetc</span><span class="plain">(</span><span class="identifier">FROM</span><span class="plain">);</span>
|
|
<span class="reserved">if</span><span class="plain"> (</span><span class="identifier">c</span><span class="plain"> == </span><span class="identifier">EOF</span><span class="plain">) </span><span class="reserved">break</span><span class="plain">;</span>
|
|
<span class="identifier">size</span><span class="plain">++;</span>
|
|
<span class="identifier">putc</span><span class="plain">(</span><span class="identifier">c</span><span class="plain">, </span><span class="identifier">TO</span><span class="plain">);</span>
|
|
<span class="plain">}</span>
|
|
|
|
<span class="functiontext"><a href="#SP8">BinaryFiles::close</a></span><span class="plain">(</span><span class="identifier">FROM</span><span class="plain">); </span><span class="functiontext"><a href="#SP8">BinaryFiles::close</a></span><span class="plain">(</span><span class="identifier">TO</span><span class="plain">);</span>
|
|
<span class="reserved">return</span><span class="plain"> </span><span class="identifier">size</span><span class="plain">;</span>
|
|
<span class="plain">}</span>
|
|
</pre>
|
|
|
|
<p class="inwebparagraph"></p>
|
|
|
|
<hr class="tocbar">
|
|
<ul class="toc"><li><i>(This section begins Chapter 6: Media.)</i></li><li><a href="6-id.html">Continue with 'Image Dimensions'</a></li></ul><hr class="tocbar">
|
|
<!--End of weave-->
|
|
<script>
|
|
function togglePopup(material_id) {
|
|
var popup = document.getElementById(material_id);
|
|
popup.classList.toggle("show");
|
|
}
|
|
</script>
|
|
|
|
<link href="Popups.css" rel="stylesheet" rev="stylesheet" type="text/css">
|
|
</main>
|
|
</body>
|
|
</html>
|
|
|