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Beman
2015-02-23 08:06:31 -05:00
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@@ -1,4 +1,4 @@
<html> <html>
<head> <head>
<meta http-equiv="Content-Language" content="en-us"> <meta http-equiv="Content-Language" content="en-us">
@@ -86,19 +86,25 @@ endian</b></i> and <i><b>little endian</b></i>.</p>
<p>Boost endian integers provide the same full set of C++ assignment, <p>Boost endian integers provide the same full set of C++ assignment,
arithmetic, and relational operators&nbsp;as C++ standard integral types, with arithmetic, and relational operators&nbsp;as C++ standard integral types, with
the standard semantics.</p> the standard semantics.</p>
<p>Unary arithmetic operators are <code>+</code>, <code>-</code>, <code>~</code>, <p>Unary arithmetic operators are <b> <code><font face="Courier New">+</font></code></b>,
<code>!</code>, prefix and postfix <code>--</code> and <code>++</code>. Binary <b> <code>-</code></b>, <b> <code>~</code></b>, <b>
arithmetic operators are <code>+</code>, <code>+=</code>, <code>-</code>, <code> <code>!</code></b>, plus both prefix and postfix <b> <code>--</code></b> and <b> <code>++</code></b>. Binary
-=</code>, <code>*</code>, <code>*=</code>, <code>/</code>, <code>/=</code>, arithmetic operators are <b> <code>+</code></b>, <b> <code>+=</code></b>, <b> <code>-</code></b>,
<code>%/ %=</code>, <code>&amp;</code>, <code>&amp;=</code>, <code>|</code>, <code>|=</code>, <b> <code>
<code>^</code>, <code>^=</code>, <code>&lt;&lt;</code>, <code>&lt;&lt;=</code>, <code>&gt;&gt;</code>, -=</code></b>, <b> <code>*</code></b>, <b> <code>*=</code></b>, <b> <code>/</code></b>,
<code>&gt;&gt;=</code>. Binary relational operators are <code>==</code>, <code>!=</code>, <b> <code>/=</code></b>, <b> <code>&amp;</code></b>, <b> <code>&amp;=</code></b>,
<code>&lt;</code>, <code>&lt;=</code>, <code>&gt;</code>, <code>&gt;=</code>.</p> <b> <code>|</code></b>, <b> <code>|=</code></b>, <b>
<p>Automatic implicit conversion to the underlying value type is provided. A <code>^</code></b>, <b> <code>^=</code></b>, <b> <code>&lt;&lt;</code></b>, <b> <code>&lt;&lt;=</code></b>, <code>
conversion constructor from the underlying value type is provided. </p> <b>&gt;&gt;</b></code>, and <b>
<code>&gt;&gt;=</code></b>. Binary relational operators are <b> <code>==</code></b>,
<b> <code>!=</code></b>, <b>
<code>&lt;</code></b>, <b> <code>&lt;=</code></b>, <b> <code>&gt;</code></b>,
and <b> <code>&gt;=</code></b>.</p>
<p>Implicit conversion to the underlying value type is provided. An implicit
constructor converting from the underlying value type is provided. </p>
<h2><a name="Example">Example</a></h2> <h2><a name="Example">Example</a></h2>
<p>The <a href="../example/endian_example.cpp">endian_example.cpp</a> program writes a <p>The <a href="../example/endian_example.cpp">endian_example.cpp</a> program writes a
binary file containing four byte big-endian and little-endian integers:</p> binary file containing four-byte, big-endian and little-endian integers:</p>
<blockquote> <blockquote>
<pre>#include &lt;iostream&gt; <pre>#include &lt;iostream&gt;
#include &lt;cstdio&gt; #include &lt;cstdio&gt;
@@ -128,10 +134,10 @@ namespace
int main(int, char* []) int main(int, char* [])
{ {
BOOST_STATIC_ASSERT(sizeof(header) == 16U); // reality check
header h; header h;
BOOST_STATIC_ASSERT(sizeof(h) == 16U); // reality check
h.file_code = 0x01020304; h.file_code = 0x01020304;
h.file_length = sizeof(header); h.file_length = sizeof(header);
h.version = 1; h.version = 1;
@@ -181,14 +187,14 @@ is some other value, compilation will result in an <code>#error</code>. This
restriction is in place because the design, implementation, testing, and restriction is in place because the design, implementation, testing, and
documentation has only considered issues related to 8-bit bytes, and there have documentation has only considered issues related to 8-bit bytes, and there have
been no real-world use cases presented for other sizes.</p> been no real-world use cases presented for other sizes.</p>
<p>In C++03, <code>endian</code> does not meet the requirements for POD types <p>In C++03, <code>endian_arithmetic</code> does not meet the requirements for POD types
because it has constructors, private data members, and a base class. This means because it has constructors, private data members, and a base class. This means
that common use cases are relying on unspecified behavior in that the C++ that common use cases are relying on unspecified behavior in that the C++
Standard does not guarantee memory layout for non-POD types. This has not been a Standard does not guarantee memory layout for non-POD types. This has not been a
problem in practice since all known C++ compilers do layout memory as if <code> problem in practice since all known C++ compilers lay out memory as if <code>
endian</code> were a POD type. In C++11, it is possible to specify the endian</code> were a POD type. In C++11, it is possible to specify the
default constructor as trivial, and private data members and base classes will default constructor as trivial, and private data members and base classes no longer disqualify a type from being a POD
no longer disqualify a type from being a POD. Thus under C++11, <code>endian</code> type. Thus under C++11, <code>endian_arithmetic</code>
will no longer be relying on unspecified behavior.</p> will no longer be relying on unspecified behavior.</p>
<h2><a name="Feature-set">Feature set</a></h2> <h2><a name="Feature-set">Feature set</a></h2>
<ul> <ul>
@@ -196,7 +202,7 @@ will no longer be relying on unspecified behavior.</p>
<li>Signed | unsigned</li> <li>Signed | unsigned</li>
<li>Unaligned | aligned</li> <li>Unaligned | aligned</li>
<li>Integer | floating point</li> <li>Integer | floating point</li>
<li>1-8 byte (unaligned) | 2, 4, 8 byte (aligned)</li> <li>1-8 byte (unaligned) | 1, 2, 4, 8 byte (aligned)</li>
<li>Choice of value type</li> <li>Choice of value type</li>
</ul> </ul>
<h2>Enums and t<a name="Types">ypedefs</a></h2> <h2>Enums and t<a name="Types">ypedefs</a></h2>
@@ -213,7 +219,7 @@ enum class align {no, yes}; </pre>
class endian_arithmetic; class endian_arithmetic;
</pre> </pre>
</blockquote> </blockquote>
<p>Typedefs, such as <code>big_int32_ut</code>, provide convenient naming <p>Typedefs, such as <code>big_int32_t</code>, provide convenient naming
conventions for common use cases:</p> conventions for common use cases:</p>
<blockquote> <blockquote>
<table border="1" cellpadding="5" cellspacing="0" style="border-collapse: collapse" bordercolor="#111111" width="49%"> <table border="1" cellpadding="5" cellspacing="0" style="border-collapse: collapse" bordercolor="#111111" width="49%">
@@ -225,112 +231,112 @@ conventions for common use cases:</p>
<td width="15%" align="center"><b><i>Sizes in bits (n)</i></b></td> <td width="15%" align="center"><b><i>Sizes in bits (n)</i></b></td>
</tr> </tr>
<tr> <tr>
<td width="18%"><code>big_int</code><b><i>n</i></b><code>_ut</code></td> <td width="18%"><code>big_int</code><b><i>n</i></b><code>_t</code></td>
<td width="49%" align="center"><code>no</code></td> <td width="49%" align="center"><code>no</code></td>
<td width="10%" align="center"><code>big</code></td> <td width="10%" align="center"><code>big</code></td>
<td width="10%" align="center">signed</td> <td width="10%" align="center">signed</td>
<td width="15%">8,16,24,32,40,48,56,64</td> <td width="15%">8,16,24,32,40,48,56,64</td>
</tr> </tr>
<tr>
<td width="18%"><code>big_uint</code><i><b>n</b></i><code>_ut</code></td>
<td width="49%" align="center"><code>no</code></td>
<td width="10%" align="center"><code>big</code></td>
<td width="10%" align="center">unsigned</td>
<td width="15%">8,16,24,32,40,48,56,64</td>
</tr>
<tr>
<td width="18%"><code>big_float</code><i><b>n</b></i><code>_ut</code></td>
<td width="49%" align="center"><code>no</code></td>
<td width="10%" align="center"><code>big</code></td>
<td width="10%" align="center">signed</td>
<td width="15%">32,64</td>
</tr>
<tr>
<td width="18%"><code>little_int</code><i><b>n</b></i><code>_ut</code></td>
<td width="49%" align="center"><code>no</code></td>
<td width="10%" align="center"><code>little</code></td>
<td width="10%" align="center">signed</td>
<td width="15%">8,16,24,32,40,48,56,64</td>
</tr>
<tr>
<td width="18%"><code>little_uint</code><i><b>n</b></i><code>_ut</code></td>
<td width="49%" align="center"><code>no</code></td>
<td width="10%" align="center"><code>little</code></td>
<td width="10%" align="center">unsigned</td>
<td width="15%">8,16,24,32,40,48,56,64</td>
</tr>
<tr>
<td width="18%"><code>little_float</code><i><b>n</b></i><code>_ut</code></td>
<td width="49%" align="center"><code>no</code></td>
<td width="10%" align="center"><code>little</code></td>
<td width="10%" align="center">signed</td>
<td width="15%">32,64</td>
</tr>
<tr>
<td width="18%"><code>native_int</code><i><b>n</b></i><code>_ut</code></td>
<td width="49%" align="center"><code>no</code></td>
<td width="10%" align="center"><code>native</code></td>
<td width="10%" align="center">signed</td>
<td width="15%">8,16,24,32,40,48,56,64</td>
</tr>
<tr>
<td width="18%"><code>native_uint</code><i><b>n</b></i><code>_ut</code></td>
<td width="49%" align="center"><code>no</code></td>
<td width="10%" align="center"><code>native</code></td>
<td width="10%" align="center">unsigned</td>
<td width="15%">8,16,24,32,40,48,56,64</td>
</tr>
<tr>
<td width="18%"><code>native_float</code><i><b>n</b></i><code>_ut</code></td>
<td width="49%" align="center"><code>no</code></td>
<td width="10%" align="center"><code>native</code></td>
<td width="10%" align="center">signed</td>
<td width="15%">32,64</td>
</tr>
<tr>
<td width="18%"><code>big_int</code><i><b>n</b></i><code>_t</code></td>
<td width="49%" align="center"><code>yes</code></td>
<td width="10%" align="center"><code>big</code></td>
<td width="10%" align="center">signed</td>
<td width="15%">8,16,32,64</td>
</tr>
<tr> <tr>
<td width="18%"><code>big_uint</code><i><b>n</b></i><code>_t</code></td> <td width="18%"><code>big_uint</code><i><b>n</b></i><code>_t</code></td>
<td width="49%" align="center"><code>no</code></td>
<td width="10%" align="center"><code>big</code></td>
<td width="10%" align="center">unsigned</td>
<td width="15%">8,16,24,32,40,48,56,64</td>
</tr>
<tr>
<td width="18%"><code>big_float</code><i><b>n</b></i><code>_t</code></td>
<td width="49%" align="center"><code>no</code></td>
<td width="10%" align="center"><code>big</code></td>
<td width="10%" align="center">signed</td>
<td width="15%">32,64</td>
</tr>
<tr>
<td width="18%"><code>little_int</code><i><b>n</b></i><code>_t</code></td>
<td width="49%" align="center"><code>no</code></td>
<td width="10%" align="center"><code>little</code></td>
<td width="10%" align="center">signed</td>
<td width="15%">8,16,24,32,40,48,56,64</td>
</tr>
<tr>
<td width="18%"><code>little_uint</code><i><b>n</b></i><code>_t</code></td>
<td width="49%" align="center"><code>no</code></td>
<td width="10%" align="center"><code>little</code></td>
<td width="10%" align="center">unsigned</td>
<td width="15%">8,16,24,32,40,48,56,64</td>
</tr>
<tr>
<td width="18%"><code>little_float</code><i><b>n</b></i><code>_t</code></td>
<td width="49%" align="center"><code>no</code></td>
<td width="10%" align="center"><code>little</code></td>
<td width="10%" align="center">signed</td>
<td width="15%">32,64</td>
</tr>
<tr>
<td width="18%"><code>native_int</code><i><b>n</b></i><code>_t</code></td>
<td width="49%" align="center"><code>no</code></td>
<td width="10%" align="center"><code>native</code></td>
<td width="10%" align="center">signed</td>
<td width="15%">8,16,24,32,40,48,56,64</td>
</tr>
<tr>
<td width="18%"><code>native_uint</code><i><b>n</b></i><code>_t</code></td>
<td width="49%" align="center"><code>no</code></td>
<td width="10%" align="center"><code>native</code></td>
<td width="10%" align="center">unsigned</td>
<td width="15%">8,16,24,32,40,48,56,64</td>
</tr>
<tr>
<td width="18%"><code>native_float</code><i><b>n</b></i><code>_t</code></td>
<td width="49%" align="center"><code>no</code></td>
<td width="10%" align="center"><code>native</code></td>
<td width="10%" align="center">signed</td>
<td width="15%">32,64</td>
</tr>
<tr>
<td width="18%"><code>big_int</code><i><b>n</b></i><code>_at</code></td>
<td width="49%" align="center"><code>yes</code></td>
<td width="10%" align="center"><code>big</code></td>
<td width="10%" align="center">signed</td>
<td width="15%">8,16,32,64</td>
</tr>
<tr>
<td width="18%"><code>big_uint</code><i><b>n</b></i><code>_at</code></td>
<td width="49%" align="center"><code>yes</code></td> <td width="49%" align="center"><code>yes</code></td>
<td width="10%" align="center"><code>big</code></td> <td width="10%" align="center"><code>big</code></td>
<td width="10%" align="center">unsigned</td> <td width="10%" align="center">unsigned</td>
<td width="15%">8,16,32,64</td> <td width="15%">8,16,32,64</td>
</tr> </tr>
<tr> <tr>
<td width="18%"><code>big_float</code><i><b>n</b></i><code>_t</code></td> <td width="18%"><code>big_float</code><i><b>n</b></i><code>_at</code></td>
<td width="49%" align="center"><code>yes</code></td> <td width="49%" align="center"><code>yes</code></td>
<td width="10%" align="center"><code>big</code></td> <td width="10%" align="center"><code>big</code></td>
<td width="10%" align="center">signed</td> <td width="10%" align="center">signed</td>
<td width="15%">32,64</td> <td width="15%">32,64</td>
</tr> </tr>
<tr> <tr>
<td width="18%" dir="ltr"><code>little_int</code><i><b>n</b></i><code>_t</code></td> <td width="18%" dir="ltr"><code>little_int</code><i><b>n</b></i><code>_at</code></td>
<td width="49%" align="center" dir="ltr"><code>yes</code></td> <td width="49%" align="center" dir="ltr"><code>yes</code></td>
<td width="10%" align="center" dir="ltr"><code>little</code></td> <td width="10%" align="center" dir="ltr"><code>little</code></td>
<td width="10%" align="center" dir="ltr">signed</td> <td width="10%" align="center" dir="ltr">signed</td>
<td width="15%" dir="ltr">8,16,32,64</td> <td width="15%" dir="ltr">8,16,32,64</td>
</tr> </tr>
<tr> <tr>
<td width="18%" dir="ltr"><code>little_uint</code><i><b>n</b></i><code>_t</code></td> <td width="18%" dir="ltr"><code>little_uint</code><i><b>n</b></i><code>_at</code></td>
<td width="49%" align="center" dir="ltr"><code>yes</code></td> <td width="49%" align="center" dir="ltr"><code>yes</code></td>
<td width="10%" align="center" dir="ltr"><code>little</code></td> <td width="10%" align="center" dir="ltr"><code>little</code></td>
<td width="10%" align="center" dir="ltr">unsigned</td> <td width="10%" align="center" dir="ltr">unsigned</td>
<td width="15%" dir="ltr">8,16,32,64</td> <td width="15%" dir="ltr">8,16,32,64</td>
</tr> </tr>
<tr> <tr>
<td width="18%" dir="ltr"><code>little_float</code><i><b>n</b></i><code>_t</code></td> <td width="18%" dir="ltr"><code>little_float</code><i><b>n</b></i><code>_at</code></td>
<td width="49%" align="center" dir="ltr"><code>yes</code></td> <td width="49%" align="center" dir="ltr"><code>yes</code></td>
<td width="10%" align="center" dir="ltr"><code>little</code></td> <td width="10%" align="center" dir="ltr"><code>little</code></td>
<td width="10%" align="center" dir="ltr">signed</td> <td width="10%" align="center" dir="ltr">signed</td>
<td width="15%" dir="ltr">32,64</td> <td width="15%" dir="ltr">32,64</td>
</tr> </tr>
<tr> <tr>
<td width="18%"><code>native_float</code><i><b>n</b></i><code>_t</code></td> <td width="18%"><code>native_float</code><i><b>n</b></i><code>_at</code></td>
<td width="49%" align="center"><code>yes</code></td> <td width="49%" align="center"><code>yes</code></td>
<td width="10%" align="center"><code>native</code></td> <td width="10%" align="center"><code>native</code></td>
<td width="10%" align="center">signed</td> <td width="10%" align="center">signed</td>
@@ -347,14 +353,14 @@ requirements vary between hardware architectures and because alignment may be
affected by compiler switches or pragmas. For example, alignment of an 64-bit affected by compiler switches or pragmas. For example, alignment of an 64-bit
integer may be to a 32-bit boundary on a 32-bit machine. Furthermore, aligned types integer may be to a 32-bit boundary on a 32-bit machine. Furthermore, aligned types
are only available on architectures with 8, 16, 32, and 64-bit integer types.</p> are only available on architectures with 8, 16, 32, and 64-bit integer types.</p>
<p><i><b>Recommendation:</b></i> Prefer unaligned endian types.</p> <p><i><b>Recommendation:</b></i> Prefer unaligned arithmetic types.</p>
<p><i><b>Recommendation:</b></i> Protect yourself against alignment ills. For <p><i><b>Recommendation:</b></i> Protect yourself against alignment ills. For
example:</p> example:</p>
<blockquote> <blockquote>
<pre>static_assert(sizeof(containing_struct) == 12, &quot;sizeof(containing_struct) is wrong&quot;); </pre> <pre>static_assert(sizeof(containing_struct) == 12, &quot;sizeof(containing_struct) is wrong&quot;); </pre>
</blockquote> </blockquote>
<p><b><i>Note:</i></b> One-byte big and little buffer types <p><b><i>Note:</i></b> <b><i>Note:</i></b> One-byte arithmetic types
never actually reverse endianness. They are provided to enable generic code, and have identical layout on all platforms, so they never actually reverse endianness. They are provided to enable generic code, and
to improve code readability and searchability.</p> to improve code readability and searchability.</p>
<h2><a name="Class_template_endian">Class template <code>endian</code></a><code>_arithmetic</code></h2> <h2><a name="Class_template_endian">Class template <code>endian</code></a><code>_arithmetic</code></h2>
<p>An endian is an integer byte-holder with user-specified <a href="#endianness"> <p>An endian is an integer byte-holder with user-specified <a href="#endianness">
@@ -427,109 +433,109 @@ usual operations on integers are supplied.</p>
// typedefs // typedefs
// aligned big endian floating point types // unaligned big endian signed integer types
typedef endian&lt;order::big, float, 32, align::yes&gt; big_float32_t; typedef endian&lt;order::big, int_least8_t, 8&gt; big_int8_t;
typedef endian&lt;order::big, double, 64, align::yes&gt; big_float64_t; typedef endian&lt;order::big, int_least16_t, 16&gt; big_int16_t;
typedef endian&lt;order::big, int_least32_t, 24&gt; big_int24_t;
typedef endian&lt;order::big, int_least32_t, 32&gt; big_int32_t;
typedef endian&lt;order::big, int_least64_t, 40&gt; big_int40_t;
typedef endian&lt;order::big, int_least64_t, 48&gt; big_int48_t;
typedef endian&lt;order::big, int_least64_t, 56&gt; big_int56_t;
typedef endian&lt;order::big, int_least64_t, 64&gt; big_int64_t;
// aligned little endian floating point types // unaligned big endian unsigned integer types
typedef endian&lt;order::little, float, 32, align::yes&gt; little_float32_t; typedef endian&lt;order::big, uint_least8_t, 8&gt; big_uint8_t;
typedef endian&lt;order::little, double, 64, align::yes&gt; little_float64_t; typedef endian&lt;order::big, uint_least16_t, 16&gt; big_uint16_t;
typedef endian&lt;order::big, uint_least32_t, 24&gt; big_uint24_t;
typedef endian&lt;order::big, uint_least32_t, 32&gt; big_uint32_t;
typedef endian&lt;order::big, uint_least64_t, 40&gt; big_uint40_t;
typedef endian&lt;order::big, uint_least64_t, 48&gt; big_uint48_t;
typedef endian&lt;order::big, uint_least64_t, 56&gt; big_uint56_t;
typedef endian&lt;order::big, uint_least64_t, 64&gt; big_uint64_t;
// unaligned big endian floating point types // unaligned big endian floating point types
typedef endian&lt;order::big, float, 32, align::no&gt; big_float32_ut; typedef endian&lt;order::big, float, 32&gt; big_float32_t;
typedef endian&lt;order::big, double, 64, align::no&gt; big_float64_ut; typedef endian&lt;order::big, double, 64&gt; big_float64_t;
// unaligned little endian signed integer types
typedef endian&lt;order::little, int_least8_t, 8&gt; little_int8_t;
typedef endian&lt;order::little, int_least16_t, 16&gt; little_int16_t;
typedef endian&lt;order::little, int_least32_t, 24&gt; little_int24_t;
typedef endian&lt;order::little, int_least32_t, 32&gt; little_int32_t;
typedef endian&lt;order::little, int_least64_t, 40&gt; little_int40_t;
typedef endian&lt;order::little, int_least64_t, 48&gt; little_int48_t;
typedef endian&lt;order::little, int_least64_t, 56&gt; little_int56_t;
typedef endian&lt;order::little, int_least64_t, 64&gt; little_int64_t;
// unaligned little endian unsigned integer types
typedef endian&lt;order::little, uint_least8_t, 8&gt; little_uint8_t;
typedef endian&lt;order::little, uint_least16_t, 16&gt; little_uint16_t;
typedef endian&lt;order::little, uint_least32_t, 24&gt; little_uint24_t;
typedef endian&lt;order::little, uint_least32_t, 32&gt; little_uint32_t;
typedef endian&lt;order::little, uint_least64_t, 40&gt; little_uint40_t;
typedef endian&lt;order::little, uint_least64_t, 48&gt; little_uint48_t;
typedef endian&lt;order::little, uint_least64_t, 56&gt; little_uint56_t;
typedef endian&lt;order::little, uint_least64_t, 64&gt; little_uint64_t;
// unaligned little endian floating point types // unaligned little endian floating point types
typedef endian&lt;order::little, float, 32, align::no&gt; little_float32_ut; typedef endian&lt;order::little, float, 32, align::no&gt; little_float32_t;
typedef endian&lt;order::little, double, 64, align::no&gt; little_float64_ut; typedef endian&lt;order::little, double, 64, align::no&gt; little_float64_t;
// unaligned native endian signed integer types
typedef <b><i>implementation-defined</i></b>_int8_t native_int8_t;
typedef <b><i>implementation-defined</i></b>_int16_t native_int16_t;
typedef <b><i>implementation-defined</i></b>_int24_t native_int24_t;
typedef <b><i>implementation-defined</i></b>_int32_t native_int32_t;
typedef <b><i>implementation-defined</i></b>_int40_t native_int40_t;
typedef <b><i>implementation-defined</i></b>_int48_t native_int48_t;
typedef <b><i>implementation-defined</i></b>_int56_t native_int56_t;
typedef <b><i>implementation-defined</i></b>_int64_t native_int64_t;
// unaligned native endian unsigned integer types
typedef <b><i>implementation-defined</i></b>_uint8_t native_uint8_t;
typedef <b><i>implementation-defined</i></b>_uint16_t native_uint16_t;
typedef <b><i>implementation-defined</i></b>_uint24_t native_uint24_t;
typedef <b><i>implementation-defined</i></b>_uint32_t native_uint32_t;
typedef <b><i>implementation-defined</i></b>_uint40_t native_uint40_t;
typedef <b><i>implementation-defined</i></b>_uint48_t native_uint48_t;
typedef <b><i>implementation-defined</i></b>_uint56_t native_uint56_t;
typedef <b><i>implementation-defined</i></b>_uint64_t native_uint64_t;
// aligned big endian signed integer types // aligned big endian signed integer types
typedef endian&lt;order::big, int8_t, 8, align::yes&gt; big_int8_t; typedef endian&lt;order::big, int8_t, 8, align::yes&gt; big_int8_at;
typedef endian&lt;order::big, int16_t, 16, align::yes&gt; big_int16_t; typedef endian&lt;order::big, int16_t, 16, align::yes&gt; big_int16_at;
typedef endian&lt;order::big, int32_t, 32, align::yes&gt; big_int32_t; typedef endian&lt;order::big, int32_t, 32, align::yes&gt; big_int32_at;
typedef endian&lt;order::big, int64_t, 64, align::yes&gt; big_int64_t; typedef endian&lt;order::big, int64_t, 64, align::yes&gt; big_int64_at;
// aligned big endian unsigned integer types // aligned big endian unsigned integer types
typedef endian&lt;order::big, uint8_t, 8, align::yes&gt; big_uint8_t; typedef endian&lt;order::big, uint8_t, 8, align::yes&gt; big_uint8_at;
typedef endian&lt;order::big, uint16_t, 16, align::yes&gt; big_uint16_t; typedef endian&lt;order::big, uint16_t, 16, align::yes&gt; big_uint16_at;
typedef endian&lt;order::big, uint32_t, 32, align::yes&gt; big_uint32_t; typedef endian&lt;order::big, uint32_t, 32, align::yes&gt; big_uint32_at;
typedef endian&lt;order::big, uint64_t, 64, align::yes&gt; big_uint64_t; typedef endian&lt;order::big, uint64_t, 64, align::yes&gt; big_uint64_at;
// aligned big endian floating point types
typedef endian&lt;order::big, float, 32, align::yes&gt; big_float32_at;
typedef endian&lt;order::big, double, 64, align::yes&gt; big_float64_at;
// aligned little endian signed integer types // aligned little endian signed integer types
typedef endian&lt;order::little, int8_t, 8, align::yes&gt; little_int8_t; typedef endian&lt;order::little, int8_t, 8, align::yes&gt; little_int8_at;
typedef endian&lt;order::little, int16_t, 16, align::yes&gt; little_int16_t; typedef endian&lt;order::little, int16_t, 16, align::yes&gt; little_int16_at;
typedef endian&lt;order::little, int32_t, 32, align::yes&gt; little_int32_t; typedef endian&lt;order::little, int32_t, 32, align::yes&gt; little_int32_at;
typedef endian&lt;order::little, int64_t, 64, align::yes&gt; little_int64_t; typedef endian&lt;order::little, int64_t, 64, align::yes&gt; little_int64_at;
// aligned little endian unsigned integer types // aligned little endian unsigned integer types
typedef endian&lt;order::little, uint8_t, 8, align::yes&gt; little_uint8_t; typedef endian&lt;order::little, uint8_t, 8, align::yes&gt; little_uint8_at;
typedef endian&lt;order::little, uint16_t, 16, align::yes&gt; little_uint16_t; typedef endian&lt;order::little, uint16_t, 16, align::yes&gt; little_uint16_at;
typedef endian&lt;order::little, uint32_t, 32, align::yes&gt; little_uint32_t; typedef endian&lt;order::little, uint32_t, 32, align::yes&gt; little_uint32_at;
typedef endian&lt;order::little, uint64_t, 64, align::yes&gt; little_uint64_t; typedef endian&lt;order::little, uint64_t, 64, align::yes&gt; little_uint64_at;
// aligned little endian floating point types
typedef endian&lt;order::little, float, 32, align::yes&gt; little_float32_at;
typedef endian&lt;order::little, double, 64, align::yes&gt; little_float64_at;
// aligned native endian typedefs are not provided because // aligned native endian typedefs are not provided because
// &lt;cstdint&gt; types are superior for that use case // &lt;cstdint&gt; types are superior for that use case
// unaligned big endian signed integer types
typedef endian&lt;order::big, int_least8_t, 8&gt; big_int8_ut;
typedef endian&lt;order::big, int_least16_t, 16&gt; big_int16_ut;
typedef endian&lt;order::big, int_least32_t, 24&gt; big_int24_ut;
typedef endian&lt;order::big, int_least32_t, 32&gt; big_int32_ut;
typedef endian&lt;order::big, int_least64_t, 40&gt; big_int40_ut;
typedef endian&lt;order::big, int_least64_t, 48&gt; big_int48_ut;
typedef endian&lt;order::big, int_least64_t, 56&gt; big_int56_ut;
typedef endian&lt;order::big, int_least64_t, 64&gt; big_int64_ut;
// unaligned big endian unsigned integer types
typedef endian&lt;order::big, uint_least8_t, 8&gt; big_uint8_ut;
typedef endian&lt;order::big, uint_least16_t, 16&gt; big_uint16_ut;
typedef endian&lt;order::big, uint_least32_t, 24&gt; big_uint24_ut;
typedef endian&lt;order::big, uint_least32_t, 32&gt; big_uint32_ut;
typedef endian&lt;order::big, uint_least64_t, 40&gt; big_uint40_ut;
typedef endian&lt;order::big, uint_least64_t, 48&gt; big_uint48_ut;
typedef endian&lt;order::big, uint_least64_t, 56&gt; big_uint56_ut;
typedef endian&lt;order::big, uint_least64_t, 64&gt; big_uint64_ut;
// unaligned little endian signed integer types
typedef endian&lt;order::little, int_least8_t, 8&gt; little_int8_ut;
typedef endian&lt;order::little, int_least16_t, 16&gt; little_int16_ut;
typedef endian&lt;order::little, int_least32_t, 24&gt; little_int24_ut;
typedef endian&lt;order::little, int_least32_t, 32&gt; little_int32_ut;
typedef endian&lt;order::little, int_least64_t, 40&gt; little_int40_ut;
typedef endian&lt;order::little, int_least64_t, 48&gt; little_int48_ut;
typedef endian&lt;order::little, int_least64_t, 56&gt; little_int56_ut;
typedef endian&lt;order::little, int_least64_t, 64&gt; little_int64_ut;
// unaligned little endian unsigned integer types
typedef endian&lt;order::little, uint_least8_t, 8&gt; little_uint8_ut;
typedef endian&lt;order::little, uint_least16_t, 16&gt; little_uint16_ut;
typedef endian&lt;order::little, uint_least32_t, 24&gt; little_uint24_ut;
typedef endian&lt;order::little, uint_least32_t, 32&gt; little_uint32_ut;
typedef endian&lt;order::little, uint_least64_t, 40&gt; little_uint40_ut;
typedef endian&lt;order::little, uint_least64_t, 48&gt; little_uint48_ut;
typedef endian&lt;order::little, uint_least64_t, 56&gt; little_uint56_ut;
typedef endian&lt;order::little, uint_least64_t, 64&gt; little_uint64_ut;
// unaligned native endian signed integer types
typedef <b><i>implementation-defined</i></b>_int8_t native_int8_ut;
typedef <b><i>implementation-defined</i></b>_int16_t native_int16_ut;
typedef <b><i>implementation-defined</i></b>_int24_t native_int24_ut;
typedef <b><i>implementation-defined</i></b>_int32_t native_int32_ut;
typedef <b><i>implementation-defined</i></b>_int40_t native_int40_ut;
typedef <b><i>implementation-defined</i></b>_int48_t native_int48_ut;
typedef <b><i>implementation-defined</i></b>_int56_t native_int56_ut;
typedef <b><i>implementation-defined</i></b>_int64_t native_int64_ut;
// unaligned native endian unsigned integer types
typedef <b><i>implementation-defined</i></b>_uint8_t native_uint8_ut;
typedef <b><i>implementation-defined</i></b>_uint16_t native_uint16_ut;
typedef <b><i>implementation-defined</i></b>_uint24_t native_uint24_ut;
typedef <b><i>implementation-defined</i></b>_uint32_t native_uint32_ut;
typedef <b><i>implementation-defined</i></b>_uint40_t native_uint40_ut;
typedef <b><i>implementation-defined</i></b>_uint48_t native_uint48_ut;
typedef <b><i>implementation-defined</i></b>_uint56_t native_uint56_ut;
typedef <b><i>implementation-defined</i></b>_uint64_t native_uint64_ut;
} // namespace endian } // namespace endian
} // namespace boost</pre> } // namespace boost</pre>
<p>The <i><b><code>implementation-defined</code></b></i> text above is either <p>The <i><b><code>implementation-defined</code></b></i> text above is either
@@ -540,11 +546,11 @@ platform.</p>
<pre><code><a name="endian">endian</a>() = default; // C++03: endian(){}</code></pre> <pre><code><a name="endian">endian</a>() = default; // C++03: endian(){}</code></pre>
</div> </div>
<blockquote> <blockquote>
<p><i>Effects:</i> Constructs an object of type <code>endian&lt;E, T, n_bits, A&gt;</code>.</p> <p><i>Effects:</i> Constructs an uninitialized object of type <code>endian_arithmetic&lt;E, T, n_bits, A&gt;</code>.</p>
</blockquote> </blockquote>
<pre><code><a name="explicit-endian">endian</a>(T v);</code></pre> <pre><code><a name="explicit-endian">endian</a>(T v);</code></pre>
<blockquote> <blockquote>
<p><i>Effects:</i> Constructs an object of type <code>endian&lt;E, T, n_bits, A&gt;</code>.</p> <p><i>Effects:</i> Constructs an object of type <code>endian_arithmetic&lt;E, T, n_bits, A&gt;</code>.</p>
<p><i>Postcondition:</i> <code>x == v,</code> where <code>x</code> is the <p><i>Postcondition:</i> <code>x == v,</code> where <code>x</code> is the
constructed object.</p> constructed object.</p>
</blockquote> </blockquote>
@@ -613,8 +619,7 @@ programming.</p>
<p><b>Why bother with the aligned endian types?</b> Aligned integer operations <p><b>Why bother with the aligned endian types?</b> Aligned integer operations
may be faster (as much as 10 to 20 times faster) if the endianness and alignment of may be faster (as much as 10 to 20 times faster) if the endianness and alignment of
the type matches the endianness and alignment requirements of the machine. The code, the type matches the endianness and alignment requirements of the machine. The code,
however, is however, will be somewhat less portable than with the unaligned types.</p>
likely to be somewhat less portable than with the unaligned types.</p>
<p><b>Why provide the arithmetic operations?</b> Providing a full set of operations reduces program <p><b>Why provide the arithmetic operations?</b> Providing a full set of operations reduces program
clutter and makes code both easier to write and to read. Consider clutter and makes code both easier to write and to read. Consider
incrementing a variable in a record. It is very convenient to write:</p> incrementing a variable in a record. It is very convenient to write:</p>
@@ -688,7 +693,7 @@ differs from endian representation size. Vicente Botet and other reviewers
suggested supporting floating point types.</p> suggested supporting floating point types.</p>
<hr> <hr>
<p>Last revised: <p>Last revised:
<!--webbot bot="Timestamp" s-type="EDITED" s-format="%d %B, %Y" startspan -->17 February, 2015<!--webbot bot="Timestamp" endspan i-checksum="40541" --></p> <!--webbot bot="Timestamp" s-type="EDITED" s-format="%d %B, %Y" startspan -->23 February, 2015<!--webbot bot="Timestamp" endspan i-checksum="40534" --></p>
<p>© Copyright Beman Dawes, 2006-2009, 2013</p> <p>© Copyright Beman Dawes, 2006-2009, 2013</p>
<p>Distributed under the Boost Software License, Version 1.0. See <p>Distributed under the Boost Software License, Version 1.0. See
<a href="http://www.boost.org/LICENSE_1_0.txt">www.boost.org/ LICENSE_1_0.txt</a></p> <a href="http://www.boost.org/LICENSE_1_0.txt">www.boost.org/ LICENSE_1_0.txt</a></p>

212
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@@ -1,4 +1,4 @@
<html> <html>
<head> <head>
<meta http-equiv="Content-Language" content="en-us"> <meta http-equiv="Content-Language" content="en-us">
@@ -184,7 +184,7 @@ will no longer be relying on unspecified behavior.</p>
<li>Signed | unsigned</li> <li>Signed | unsigned</li>
<li>Unaligned | aligned</li> <li>Unaligned | aligned</li>
<li>Integer | floating point</li> <li>Integer | floating point</li>
<li>1-8 byte (unaligned) | 2, 4, 8 byte (aligned)</li> <li>1-8 byte (unaligned) | 1, 2, 4, 8 byte (aligned)</li>
<li>Choice of value type</li> <li>Choice of value type</li>
</ul> </ul>
<h2>Enums and t<a name="Types">ypedefs</a></h2> <h2>Enums and t<a name="Types">ypedefs</a></h2>
@@ -201,7 +201,7 @@ enum class align {no, yes}; </pre>
class endian_buffer; class endian_buffer;
</pre> </pre>
</blockquote> </blockquote>
<p>Typedefs, such as <code>big_int32_buf_ut</code>, provide convenient naming <p>Typedefs, such as <code>big_int32_buf_t</code>, provide convenient naming
conventions for common use cases:</p> conventions for common use cases:</p>
<blockquote> <blockquote>
<table border="1" cellpadding="5" cellspacing="0" style="border-collapse: collapse" bordercolor="#111111" width="49%"> <table border="1" cellpadding="5" cellspacing="0" style="border-collapse: collapse" bordercolor="#111111" width="49%">
@@ -213,112 +213,112 @@ conventions for common use cases:</p>
<td width="15%" align="center"><b><i>Sizes in bits (n)</i></b></td> <td width="15%" align="center"><b><i>Sizes in bits (n)</i></b></td>
</tr> </tr>
<tr> <tr>
<td width="18%" dir="ltr"><code>big_int</code><b><i>n</i></b><code>_buf_ut</code></td> <td width="18%" dir="ltr"><code>big_int</code><b><i>n</i></b><code>_buf_t</code></td>
<td width="49%" align="center" dir="ltr"><code>no</code></td> <td width="49%" align="center" dir="ltr"><code>no</code></td>
<td width="10%" align="center" dir="ltr"><code>big</code></td> <td width="10%" align="center" dir="ltr"><code>big</code></td>
<td width="10%" align="center" dir="ltr">signed</td> <td width="10%" align="center" dir="ltr">signed</td>
<td width="15%" dir="ltr">8,16,24,32,40,48,56,64</td> <td width="15%" dir="ltr">8,16,24,32,40,48,56,64</td>
</tr> </tr>
<tr> <tr>
<td width="18%" dir="ltr"><code>big_uint</code><i><b>n</b></i><code>_buf_ut</code></td> <td width="18%" dir="ltr"><code>big_uint</code><i><b>n</b></i><code>_buf_t</code></td>
<td width="49%" align="center" dir="ltr"><code>no</code></td> <td width="49%" align="center" dir="ltr"><code>no</code></td>
<td width="10%" align="center" dir="ltr"><code>big</code></td> <td width="10%" align="center" dir="ltr"><code>big</code></td>
<td width="10%" align="center" dir="ltr">unsigned</td> <td width="10%" align="center" dir="ltr">unsigned</td>
<td width="15%" dir="ltr">8,16,24,32,40,48,56,64</td> <td width="15%" dir="ltr">8,16,24,32,40,48,56,64</td>
</tr> </tr>
<tr> <tr>
<td width="18%" dir="ltr"><code>big_float</code><i><b>n</b></i><code>_buf_ut</code></td> <td width="18%" dir="ltr"><code>big_float</code><i><b>n</b></i><code>_buf_t</code></td>
<td width="49%" align="center" dir="ltr"><code>no</code></td> <td width="49%" align="center" dir="ltr"><code>no</code></td>
<td width="10%" align="center" dir="ltr"><code>big</code></td> <td width="10%" align="center" dir="ltr"><code>big</code></td>
<td width="10%" align="center" dir="ltr">signed</td> <td width="10%" align="center" dir="ltr">signed</td>
<td width="15%" dir="ltr">32,64</td> <td width="15%" dir="ltr">32,64</td>
</tr> </tr>
<tr> <tr>
<td width="18%"><code>little_int</code><i><b>n</b></i><code>_buf_ut</code></td> <td width="18%"><code>little_int</code><i><b>n</b></i><code>_buf_t</code></td>
<td width="49%" align="center"><code>no</code></td> <td width="49%" align="center"><code>no</code></td>
<td width="10%" align="center"><code>little</code></td> <td width="10%" align="center"><code>little</code></td>
<td width="10%" align="center">signed</td> <td width="10%" align="center">signed</td>
<td width="15%">8,16,24,32,40,48,56,64</td> <td width="15%">8,16,24,32,40,48,56,64</td>
</tr> </tr>
<tr> <tr>
<td width="18%"><code>little_uint</code><i><b>n</b></i><code>_buf_ut</code></td> <td width="18%"><code>little_uint</code><i><b>n</b></i><code>_buf_t</code></td>
<td width="49%" align="center"><code>no</code></td> <td width="49%" align="center"><code>no</code></td>
<td width="10%" align="center"><code>little</code></td> <td width="10%" align="center"><code>little</code></td>
<td width="10%" align="center">unsigned</td> <td width="10%" align="center">unsigned</td>
<td width="15%">8,16,24,32,40,48,56,64</td> <td width="15%">8,16,24,32,40,48,56,64</td>
</tr> </tr>
<tr> <tr>
<td width="18%"><code>little_float</code><i><b>n</b></i><code>_buf_ut</code></td> <td width="18%"><code>little_float</code><i><b>n</b></i><code>_buf_t</code></td>
<td width="49%" align="center"><code>no</code></td> <td width="49%" align="center"><code>no</code></td>
<td width="10%" align="center"><code>little</code></td> <td width="10%" align="center"><code>little</code></td>
<td width="10%" align="center">signed</td> <td width="10%" align="center">signed</td>
<td width="15%">32,64</td> <td width="15%">32,64</td>
</tr> </tr>
<tr> <tr>
<td width="18%"><code>native_int</code><i><b>n</b></i><code>_buf_ut</code></td> <td width="18%"><code>native_int</code><i><b>n</b></i><code>_buf_t</code></td>
<td width="49%" align="center"><code>no</code></td> <td width="49%" align="center"><code>no</code></td>
<td width="10%" align="center"><code>native</code></td> <td width="10%" align="center"><code>native</code></td>
<td width="10%" align="center">signed</td> <td width="10%" align="center">signed</td>
<td width="15%">8,16,24,32,40,48,56,64</td> <td width="15%">8,16,24,32,40,48,56,64</td>
</tr> </tr>
<tr> <tr>
<td width="18%"><code>native_uint</code><i><b>n</b></i><code>_buf_ut</code></td> <td width="18%"><code>native_uint</code><i><b>n</b></i><code>_buf_t</code></td>
<td width="49%" align="center"><code>no</code></td> <td width="49%" align="center"><code>no</code></td>
<td width="10%" align="center"><code>native</code></td> <td width="10%" align="center"><code>native</code></td>
<td width="10%" align="center">unsigned</td> <td width="10%" align="center">unsigned</td>
<td width="15%">8,16,24,32,40,48,56,64</td> <td width="15%">8,16,24,32,40,48,56,64</td>
</tr> </tr>
<tr> <tr>
<td width="18%"><code>native_float</code><i><b>n</b></i><code>_buf_ut</code></td> <td width="18%"><code>native_float</code><i><b>n</b></i><code>_buf_t</code></td>
<td width="49%" align="center"><code>no</code></td> <td width="49%" align="center"><code>no</code></td>
<td width="10%" align="center"><code>native</code></td> <td width="10%" align="center"><code>native</code></td>
<td width="10%" align="center">signed</td> <td width="10%" align="center">signed</td>
<td width="15%">32,64</td> <td width="15%">32,64</td>
</tr> </tr>
<tr> <tr>
<td width="18%"><code>big_int</code><i><b>n</b></i><code>_buf_t</code></td> <td width="18%"><code>big_int</code><i><b>n</b></i><code>_buf_at</code></td>
<td width="49%" align="center"><code>yes</code></td> <td width="49%" align="center"><code>yes</code></td>
<td width="10%" align="center"><code>big</code></td> <td width="10%" align="center"><code>big</code></td>
<td width="10%" align="center">signed</td> <td width="10%" align="center">signed</td>
<td width="15%">8,16,32,64</td> <td width="15%">8,16,32,64</td>
</tr> </tr>
<tr> <tr>
<td width="18%"><code>big_uint</code><i><b>n</b></i><code>_</code><code>buf_</code><code>t</code></td> <td width="18%"><code>big_uint</code><i><b>n</b></i><code>_</code><code>buf_at</code></td>
<td width="49%" align="center"><code>yes</code></td> <td width="49%" align="center"><code>yes</code></td>
<td width="10%" align="center"><code>big</code></td> <td width="10%" align="center"><code>big</code></td>
<td width="10%" align="center">unsigned</td> <td width="10%" align="center">unsigned</td>
<td width="15%">8,16,32,64</td> <td width="15%">8,16,32,64</td>
</tr> </tr>
<tr> <tr>
<td width="18%"><code>big_float</code><i><b>n</b></i><code>_</code><code>buf_</code><code>t</code></td> <td width="18%"><code>big_float</code><i><b>n</b></i><code>_</code><code>buf_at</code></td>
<td width="49%" align="center"><code>yes</code></td> <td width="49%" align="center"><code>yes</code></td>
<td width="10%" align="center"><code>big</code></td> <td width="10%" align="center"><code>big</code></td>
<td width="10%" align="center">signed</td> <td width="10%" align="center">signed</td>
<td width="15%">32,64</td> <td width="15%">32,64</td>
</tr> </tr>
<tr> <tr>
<td width="18%"><code>little_int</code><i><b>n</b></i><code>_</code><code>buf_</code><code>t</code></td> <td width="18%"><code>little_int</code><i><b>n</b></i><code>_</code><code>buf_at</code></td>
<td width="49%" align="center"><code>yes</code></td> <td width="49%" align="center"><code>yes</code></td>
<td width="10%" align="center"><code>little</code></td> <td width="10%" align="center"><code>little</code></td>
<td width="10%" align="center">signed</td> <td width="10%" align="center">signed</td>
<td width="15%">8,16,32,64</td> <td width="15%">8,16,32,64</td>
</tr> </tr>
<tr> <tr>
<td width="18%"><code>little_uint</code><i><b>n</b></i><code>_</code><code>buf_</code><code>t</code></td> <td width="18%"><code>little_uint</code><i><b>n</b></i><code>_</code><code>buf_at</code></td>
<td width="49%" align="center"><code>yes</code></td> <td width="49%" align="center"><code>yes</code></td>
<td width="10%" align="center"><code>little</code></td> <td width="10%" align="center"><code>little</code></td>
<td width="10%" align="center">unsigned</td> <td width="10%" align="center">unsigned</td>
<td width="15%">8,16,32,64</td> <td width="15%">8,16,32,64</td>
</tr> </tr>
<tr> <tr>
<td width="18%"><code>little_float</code><i><b>n</b></i><code>_</code><code>buf_</code><code>t</code></td> <td width="18%"><code>little_float</code><i><b>n</b></i><code>_</code><code>buf_at</code></td>
<td width="49%" align="center"><code>yes</code></td> <td width="49%" align="center"><code>yes</code></td>
<td width="10%" align="center"><code>little</code></td> <td width="10%" align="center"><code>little</code></td>
<td width="10%" align="center">signed</td> <td width="10%" align="center">signed</td>
<td width="15%">32,64</td> <td width="15%">32,64</td>
</tr> </tr>
<tr> <tr>
<td width="18%"><code>native_float</code><i><b>n</b></i><code>_</code><code>buf_</code><code>t</code></td> <td width="18%"><code>native_float</code><i><b>n</b></i><code>_</code><code>buf_at</code></td>
<td width="49%" align="center"><code>yes</code></td> <td width="49%" align="center"><code>yes</code></td>
<td width="10%" align="center"><code>native</code></td> <td width="10%" align="center"><code>native</code></td>
<td width="10%" align="center">signed</td> <td width="10%" align="center">signed</td>
@@ -336,7 +336,7 @@ affected by compiler switches or pragmas. For example, alignment of an 64-bit
integer may be to a 32-bit boundary on a 32-bit machine and to a 64-bit boundary integer may be to a 32-bit boundary on a 32-bit machine and to a 64-bit boundary
on a 64-bit machine. Furthermore, aligned types on a 64-bit machine. Furthermore, aligned types
are only available on architectures with 8, 16, 32, and 64-bit integer types. </p> are only available on architectures with 8, 16, 32, and 64-bit integer types. </p>
<p><i><b>Recommendation:</b></i> Prefer unaligned endian types.</p> <p><i><b>Recommendation:</b></i> Prefer unaligned buffer types.</p>
<p><i><b>Recommendation:</b></i> Protect yourself against alignment ills. For <p><i><b>Recommendation:</b></i> Protect yourself against alignment ills. For
example:</p> example:</p>
<blockquote> <blockquote>
@@ -398,105 +398,109 @@ usual operations on integers are supplied.</p>
// typedefs // typedefs
// aligned big endian floating point buffers // unaligned big endian signed integer buffers
typedef endian_buffer&lt;order::big, float, 32, align::yes&gt; big_float32_buf_t; typedef endian_buffer&lt;order::big, int_least8_t, 8&gt; big_int8_buf_t;
typedef endian_buffer&lt;order::big, double, 64, align::yes&gt; big_float64_buf_t; typedef endian_buffer&lt;order::big, int_least16_t, 16&gt; big_int16_buf_t;
typedef endian_buffer&lt;order::big, int_least32_t, 24&gt; big_int24_buf_t;
typedef endian_buffer&lt;order::big, int_least32_t, 32&gt; big_int32_buf_t;
typedef endian_buffer&lt;order::big, int_least64_t, 40&gt; big_int40_buf_t;
typedef endian_buffer&lt;order::big, int_least64_t, 48&gt; big_int48_buf_t;
typedef endian_buffer&lt;order::big, int_least64_t, 56&gt; big_int56_buf_t;
typedef endian_buffer&lt;order::big, int_least64_t, 64&gt; big_int64_buf_t;
// aligned little endian floating point buffers // unaligned big endian unsigned integer buffers
typedef endian_buffer&lt;order::little, float, 32, align::yes&gt; little_float32_buf_t; typedef endian_buffer&lt;order::big, uint_least8_t, 8&gt; big_uint8_buf_t;
typedef endian_buffer&lt;order::little, double, 64, align::yes&gt; little_float64_buf_t; typedef endian_buffer&lt;order::big, uint_least16_t, 16&gt; big_uint16_buf_t;
typedef endian_buffer&lt;order::big, uint_least32_t, 24&gt; big_uint24_buf_t;
typedef endian_buffer&lt;order::big, uint_least32_t, 32&gt; big_uint32_buf_t;
typedef endian_buffer&lt;order::big, uint_least64_t, 40&gt; big_uint40_buf_t;
typedef endian_buffer&lt;order::big, uint_least64_t, 48&gt; big_uint48_buf_t;
typedef endian_buffer&lt;order::big, uint_least64_t, 56&gt; big_uint56_buf_t;
typedef endian_buffer&lt;order::big, uint_least64_t, 64&gt; big_uint64_buf_t;
// unaligned big endian floating point buffers // unaligned big endian floating point buffers
typedef endian_buffer&lt;order::big, float, 32, align::no&gt; big_float32_buf_ut; typedef endian_buffer&lt;order::big, float, 32&gt; big_float32_buf_t;
typedef endian_buffer&lt;order::big, double, 64, align::no&gt; big_float64_buf_ut; typedef endian_buffer&lt;order::big, double, 64&gt; big_float64_buf_t;
// unaligned little endian signed integer buffers
typedef endian_buffer&lt;order::little, int_least8_t, 8&gt; little_int8_buf_t;
typedef endian_buffer&lt;order::little, int_least16_t, 16&gt; little_int16_buf_t;
typedef endian_buffer&lt;order::little, int_least32_t, 24&gt; little_int24_buf_t;
typedef endian_buffer&lt;order::little, int_least32_t, 32&gt; little_int32_buf_t;
typedef endian_buffer&lt;order::little, int_least64_t, 40&gt; little_int40_buf_t;
typedef endian_buffer&lt;order::little, int_least64_t, 48&gt; little_int48_buf_t;
typedef endian_buffer&lt;order::little, int_least64_t, 56&gt; little_int56_buf_t;
typedef endian_buffer&lt;order::little, int_least64_t, 64&gt; little_int64_buf_t;
// unaligned little endian unsigned integer buffers
typedef endian_buffer&lt;order::little, uint_least8_t, 8&gt; little_uint8_buf_t;
typedef endian_buffer&lt;order::little, uint_least16_t, 16&gt; little_uint16_buf_t;
typedef endian_buffer&lt;order::little, uint_least32_t, 24&gt; little_uint24_buf_t;
typedef endian_buffer&lt;order::little, uint_least32_t, 32&gt; little_uint32_buf_t;
typedef endian_buffer&lt;order::little, uint_least64_t, 40&gt; little_uint40_buf_t;
typedef endian_buffer&lt;order::little, uint_least64_t, 48&gt; little_uint48_buf_t;
typedef endian_buffer&lt;order::little, uint_least64_t, 56&gt; little_uint56_buf_t;
typedef endian_buffer&lt;order::little, uint_least64_t, 64&gt; little_uint64_buf_t;
// unaligned little endian floating point buffers // unaligned little endian floating point buffers
typedef endian_buffer&lt;order::little, float, 32, align::no&gt; little_float32_buf_ut; typedef endian_buffer&lt;order::little, float, 32&gt; little_float32_buf_t;
typedef endian_buffer&lt;order::little, double, 64, align::no&gt; little_float64_buf_ut; typedef endian_buffer&lt;order::little, double, 64&gt; little_float64_buf_t;
// unaligned native endian signed integer types
typedef <b><i>implementation-defined</i></b>_int8_buf_t native_int8_buf_t;
typedef <b><i>implementation-defined</i></b>_int16_buf_t native_int16_buf_t;
typedef <b><i>implementation-defined</i></b>_int24_buf_t native_int24_buf_t;
typedef <b><i>implementation-defined</i></b>_int32_buf_t native_int32_buf_t;
typedef <b><i>implementation-defined</i></b>_int40_buf_t native_int40_buf_t;
typedef <b><i>implementation-defined</i></b>_int48_buf_t native_int48_buf_t;
typedef <b><i>implementation-defined</i></b>_int56_buf_t native_int56_buf_t;
typedef <b><i>implementation-defined</i></b>_int64_buf_t native_int64_buf_t;
// unaligned native endian unsigned integer types
typedef <b><i>implementation-defined</i></b>_uint8_buf_t native_uint8_buf_t;
typedef <b><i>implementation-defined</i></b>_uint16_buf_t native_uint16_buf_t;
typedef <b><i>implementation-defined</i></b>_uint24_buf_t native_uint24_buf_t;
typedef <b><i>implementation-defined</i></b>_uint32_buf_t native_uint32_buf_t;
typedef <b><i>implementation-defined</i></b>_uint40_buf_t native_uint40_buf_t;
typedef <b><i>implementation-defined</i></b>_uint48_buf_t native_uint48_buf_t;
typedef <b><i>implementation-defined</i></b>_uint56_buf_t native_uint56_buf_t;
typedef <b><i>implementation-defined</i></b>_uint64_buf_t native_uint64_buf_t;
// aligned big endian signed integer buffers // aligned big endian signed integer buffers
typedef endian_buffer&lt;order::big, int16_t, 16, align::yes&gt; big_int16_buf_t; typedef endian_buffer&lt;order::big, int8_t, 8, align::yes&gt; big_int8_buf_at;
typedef endian_buffer&lt;order::big, int32_t, 32, align::yes&gt; big_int32_buf_t; typedef endian_buffer&lt;order::big, int16_t, 16, align::yes&gt; big_int16_buf_at;
typedef endian_buffer&lt;order::big, int64_t, 64, align::yes&gt; big_int64_buf_t; typedef endian_buffer&lt;order::big, int32_t, 32, align::yes&gt; big_int32_buf_at;
typedef endian_buffer&lt;order::big, int64_t, 64, align::yes&gt; big_int64_buf_at;
// aligned big endian unsigned integer buffers // aligned big endian unsigned integer buffers
typedef endian_buffer&lt;order::big, uint16_t, 16, align::yes&gt; big_uint16_buf_t; typedef endian_buffer&lt;order::big, uint8_t, 8, align::yes&gt; big_uint8_buf_at;
typedef endian_buffer&lt;order::big, uint32_t, 32, align::yes&gt; big_uint32_buf_t; typedef endian_buffer&lt;order::big, uint16_t, 16, align::yes&gt; big_uint16_buf_at;
typedef endian_buffer&lt;order::big, uint64_t, 64, align::yes&gt; big_uint64_buf_t; typedef endian_buffer&lt;order::big, uint32_t, 32, align::yes&gt; big_uint32_buf_at;
typedef endian_buffer&lt;order::big, uint64_t, 64, align::yes&gt; big_uint64_buf_at;
// aligned big endian floating point buffers
typedef endian_buffer&lt;order::big, float, 32, align::yes&gt; big_float32_buf_at;
typedef endian_buffer&lt;order::big, double, 64, align::yes&gt; big_float64_buf_at;
// aligned little endian signed integer buffers // aligned little endian signed integer buffers
typedef endian_buffer&lt;order::little, int16_t, 16, align::yes&gt; little_int16_buf_t; typedef endian_buffer&lt;order::little, int8_t, 8, align::yes&gt; little_int8_buf_at;
typedef endian_buffer&lt;order::little, int32_t, 32, align::yes&gt; little_int32_buf_t; typedef endian_buffer&lt;order::little, int16_t, 16, align::yes&gt; little_int16_buf_at;
typedef endian_buffer&lt;order::little, int64_t, 64, align::yes&gt; little_int64_buf_t; typedef endian_buffer&lt;order::little, int32_t, 32, align::yes&gt; little_int32_buf_at;
typedef endian_buffer&lt;order::little, int64_t, 64, align::yes&gt; little_int64_buf_at;
// aligned little endian unsigned integer buffers // aligned little endian unsigned integer buffers
typedef endian_buffer&lt;order::little, uint16_t, 16, align::yes&gt; little_uint16_buf_t; typedef endian_buffer&lt;order::little, uint8_t, 8, align::yes&gt; little_uint8_buf_at;
typedef endian_buffer&lt;order::little, uint32_t, 32, align::yes&gt; little_uint32_buf_t; typedef endian_buffer&lt;order::little, uint16_t, 16, align::yes&gt; little_uint16_buf_at;
typedef endian_buffer&lt;order::little, uint64_t, 64, align::yes&gt; little_uint64_buf_t; typedef endian_buffer&lt;order::little, uint32_t, 32, align::yes&gt; little_uint32_buf_at;
typedef endian_buffer&lt;order::little, uint64_t, 64, align::yes&gt; little_uint64_buf_at;
// aligned little endian floating point buffers
typedef endian_buffer&lt;order::little, float, 32, align::yes&gt; little_float32_buf_at;
typedef endian_buffer&lt;order::little, double, 64, align::yes&gt; little_float64_buf_at;
// aligned native endian typedefs are not provided because // aligned native endian typedefs are not provided because
// &lt;cstdint&gt; types are superior for this use case // &lt;cstdint&gt; types are superior for this use case
// unaligned big endian signed integer buffers
typedef endian_buffer&lt;order::big, int_least8_t, 8&gt; big_int8_buf_ut;
typedef endian_buffer&lt;order::big, int_least16_t, 16&gt; big_int16_buf_ut;
typedef endian_buffer&lt;order::big, int_least32_t, 24&gt; big_int24_buf_ut;
typedef endian_buffer&lt;order::big, int_least32_t, 32&gt; big_int32_buf_ut;
typedef endian_buffer&lt;order::big, int_least64_t, 40&gt; big_int40_buf_ut;
typedef endian_buffer&lt;order::big, int_least64_t, 48&gt; big_int48_buf_ut;
typedef endian_buffer&lt;order::big, int_least64_t, 56&gt; big_int56_buf_ut;
typedef endian_buffer&lt;order::big, int_least64_t, 64&gt; big_int64_buf_ut;
// unaligned big endian unsigned integer buffers
typedef endian_buffer&lt;order::big, uint_least8_t, 8&gt; big_uint8_buf_ut;
typedef endian_buffer&lt;order::big, uint_least16_t, 16&gt; big_uint16_buf_ut;
typedef endian_buffer&lt;order::big, uint_least32_t, 24&gt; big_uint24_buf_ut;
typedef endian_buffer&lt;order::big, uint_least32_t, 32&gt; big_uint32_buf_ut;
typedef endian_buffer&lt;order::big, uint_least64_t, 40&gt; big_uint40_buf_ut;
typedef endian_buffer&lt;order::big, uint_least64_t, 48&gt; big_uint48_buf_ut;
typedef endian_buffer&lt;order::big, uint_least64_t, 56&gt; big_uint56_buf_ut;
typedef endian_buffer&lt;order::big, uint_least64_t, 64&gt; big_uint64_buf_ut;
// unaligned little endian signed integer buffers
typedef endian_buffer&lt;order::little, int_least8_t, 8&gt; little_int8_buf_ut;
typedef endian_buffer&lt;order::little, int_least16_t, 16&gt; little_int16_buf_ut;
typedef endian_buffer&lt;order::little, int_least32_t, 24&gt; little_int24_buf_ut;
typedef endian_buffer&lt;order::little, int_least32_t, 32&gt; little_int32_buf_ut;
typedef endian_buffer&lt;order::little, int_least64_t, 40&gt; little_int40_buf_ut;
typedef endian_buffer&lt;order::little, int_least64_t, 48&gt; little_int48_buf_ut;
typedef endian_buffer&lt;order::little, int_least64_t, 56&gt; little_int56_buf_ut;
typedef endian_buffer&lt;order::little, int_least64_t, 64&gt; little_int64_buf_ut;
// unaligned little endian unsigned integer buffers
typedef endian_buffer&lt;order::little, uint_least8_t, 8&gt; little_uint8_buf_ut;
typedef endian_buffer&lt;order::little, uint_least16_t, 16&gt; little_uint16_buf_ut;
typedef endian_buffer&lt;order::little, uint_least32_t, 24&gt; little_uint24_buf_ut;
typedef endian_buffer&lt;order::little, uint_least32_t, 32&gt; little_uint32_buf_ut;
typedef endian_buffer&lt;order::little, uint_least64_t, 40&gt; little_uint40_buf_ut;
typedef endian_buffer&lt;order::little, uint_least64_t, 48&gt; little_uint48_buf_ut;
typedef endian_buffer&lt;order::little, uint_least64_t, 56&gt; little_uint56_buf_ut;
typedef endian_buffer&lt;order::little, uint_least64_t, 64&gt; little_uint64_buf_ut;
// unaligned native endian signed integer types
typedef <b><i>implementation-defined</i></b>_int8_buf_ut native_int8_buf_ut;
typedef <b><i>implementation-defined</i></b>_int16_buf_ut native_int16_buf_ut;
typedef <b><i>implementation-defined</i></b>_int24_buf_ut native_int24_buf_ut;
typedef <b><i>implementation-defined</i></b>_int32_buf_ut native_int32_buf_ut;
typedef <b><i>implementation-defined</i></b>_int40_buf_ut native_int40_buf_ut;
typedef <b><i>implementation-defined</i></b>_int48_buf_ut native_int48_buf_ut;
typedef <b><i>implementation-defined</i></b>_int56_buf_ut native_int56_buf_ut;
typedef <b><i>implementation-defined</i></b>_int64_buf_ut native_int64_buf_ut;
// unaligned native endian unsigned integer types
typedef <b><i>implementation-defined</i></b>_uint8_buf_ut native_uint8_buf_ut;
typedef <b><i>implementation-defined</i></b>_uint16_buf_ut native_uint16_buf_ut;
typedef <b><i>implementation-defined</i></b>_uint24_buf_ut native_uint24_buf_ut;
typedef <b><i>implementation-defined</i></b>_uint32_buf_ut native_uint32_buf_ut;
typedef <b><i>implementation-defined</i></b>_uint40_buf_ut native_uint40_buf_ut;
typedef <b><i>implementation-defined</i></b>_uint48_buf_ut native_uint48_buf_ut;
typedef <b><i>implementation-defined</i></b>_uint56_buf_ut native_uint56_buf_ut;
typedef <b><i>implementation-defined</i></b>_uint64_buf_ut native_uint64_buf_ut;
} // namespace endian } // namespace endian
} // namespace boost</pre> } // namespace boost</pre>
<p>The <i><b><code>implementation-defined</code></b></i> text in typedefs above is either <p>The <i><b><code>implementation-defined</code></b></i> text in typedefs above is either
@@ -546,7 +550,7 @@ boost::endian::endian_reverse</code>.</p>
</blockquote> </blockquote>
<pre>value_type <a name="value">value</a>()<code> const noexcept;</code></pre> <pre>value_type <a name="value">value</a>()<code> const noexcept;</code></pre>
<blockquote> <blockquote>
<p><i>Returns:</i> <code>endian_value</code>, converted to <code>value_type</code> <p><i>Returns:</i> <code>endian_value</code>, converted to <code>value_type</code>,
if required, and having the endianness of the native platform.</p> if required, and having the endianness of the native platform.</p>
<p><i>Remarks:</i> If <code>Align</code> is <code>align::yes</code> then <p><i>Remarks:</i> If <code>Align</code> is <code>align::yes</code> then
endianness conversion, if required, is performed by <code> endianness conversion, if required, is performed by <code>
@@ -659,7 +663,7 @@ any Boost object libraries.</p>
</ul> </ul>
<hr> <hr>
<p>Last revised: <p>Last revised:
<!--webbot bot="Timestamp" s-type="EDITED" s-format="%d %B, %Y" startspan -->17 February, 2015<!--webbot bot="Timestamp" endspan i-checksum="40541" --></p> <!--webbot bot="Timestamp" s-type="EDITED" s-format="%d %B, %Y" startspan -->23 February, 2015<!--webbot bot="Timestamp" endspan i-checksum="40534" --></p>
<p>© Copyright Beman Dawes, 2006-2009, 2013</p> <p>© Copyright Beman Dawes, 2006-2009, 2013</p>
<p>Distributed under the Boost Software License, Version 1.0. See <p>Distributed under the Boost Software License, Version 1.0. See
<a href="http://www.boost.org/LICENSE_1_0.txt">www.boost.org/ LICENSE_1_0.txt</a></p> <a href="http://www.boost.org/LICENSE_1_0.txt">www.boost.org/ LICENSE_1_0.txt</a></p>

18
index.html
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@@ -1,4 +1,4 @@
<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns="http://www.w3.org/TR/REC-html40"> <html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns="http://www.w3.org/TR/REC-html40">
<head> <head>
<meta name="GENERATOR" content="Microsoft FrontPage 5.0"> <meta name="GENERATOR" content="Microsoft FrontPage 5.0">
@@ -219,7 +219,7 @@ intrinsics as a source of performance issues.</p>
</tr> </tr>
<tr> <tr>
<td valign="top"> <td valign="top">
<pre>big_int32_t x; <pre>big_int32_at x;
... read into x from a file ... ... read into x from a file ...
@@ -273,7 +273,7 @@ spent doing I/O will determine the speed of this application.</p>
</tr> </tr>
<tr> <tr>
<td valign="top"> <td valign="top">
<pre>big_int32_t x; <pre>big_int32_at x;
... read into x from a file ... ... read into x from a file ...
@@ -395,7 +395,7 @@ I/O formats?</b> </p>
<blockquote> <blockquote>
<p>Using the unaligned integer types with a size tailored to the application&#39;s <p>Using the unaligned integer types with a size tailored to the application&#39;s
needs is a minor secondary use that saves internal or external memory space. For needs is a minor secondary use that saves internal or external memory space. For
example, using <code>big_int40_buf_ut</code> or <code>big_int40_ut</code> in a example, using <code>big_int40_buf_t</code> or <code>big_int40_t</code> in a
large array saves a lot of space compared to one of the 64-bit types.</p> large array saves a lot of space compared to one of the 64-bit types.</p>
</blockquote> </blockquote>
<p><b>Why bother with binary I/O? Why not just use C++ Standard Library stream <p><b>Why bother with binary I/O? Why not just use C++ Standard Library stream
@@ -489,12 +489,8 @@ review</a></h3>
<li>The endian arithmetic type aliases have been renamed, <li>The endian arithmetic type aliases have been renamed,
using a naming pattern that is consistent for both integer and floating point, using a naming pattern that is consistent for both integer and floating point,
and a consistent set of aliases supplied for the endian buffer types.</li> and a consistent set of aliases supplied for the endian buffer types.</li>
<li>The aligned-type alias names now have the <code>_t</code> suffix, for <li>The unaligned-type alias names still have the <code>_t</code> suffix, but
consistency with the standard library integer type aliases and because use of the aligned-type alias names now have an <code>_at</code> suffix..</li>
aligned types is much more common than unaligned types.</li>
<li>The unaligned-type alias names now have the <code>_ut</code> suffix. This
is short, yet stands out enough to alert the reader than unusual types are
involved.</li>
<li><code>endian_reverse()</code> overloads for <code>int8_t</code> and <code> <li><code>endian_reverse()</code> overloads for <code>int8_t</code> and <code>
uint8_t</code> have been added for improved generality. (Pierre Talbot)</li> uint8_t</code> have been added for improved generality. (Pierre Talbot)</li>
<li>Overloads of <code>endian_reverse_inplace()</code> have been replaced with a single <code> <li>Overloads of <code>endian_reverse_inplace()</code> have been replaced with a single <code>
@@ -593,7 +589,7 @@ Blechmann, Tim Moore, tymofey, Tomas Puverle, Vincente Botet, Yuval Ronen and
Vitaly Budovsk. Apologies if anyone has been missed.</p> Vitaly Budovsk. Apologies if anyone has been missed.</p>
<hr> <hr>
<p>Last revised: <p>Last revised:
<!--webbot bot="Timestamp" s-type="EDITED" s-format="%d %B, %Y" startspan -->17 February, 2015<!--webbot bot="Timestamp" endspan i-checksum="40541" --></p> <!--webbot bot="Timestamp" s-type="EDITED" s-format="%d %B, %Y" startspan -->23 February, 2015<!--webbot bot="Timestamp" endspan i-checksum="40534" --></p>
<p>© Copyright Beman Dawes, 2011, 2013</p> <p>© Copyright Beman Dawes, 2011, 2013</p>
<p>Distributed under the Boost Software License, Version 1.0. See <p>Distributed under the Boost Software License, Version 1.0. See
<a href="http://www.boost.org/LICENSE_1_0.txt">www.boost.org/ LICENSE_1_0.txt</a></p> <a href="http://www.boost.org/LICENSE_1_0.txt">www.boost.org/ LICENSE_1_0.txt</a></p>