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diff --git a/share/doc/stabs/Protections.html b/share/doc/stabs/Protections.html new file mode 100644 index 0000000..7e14163 --- /dev/null +++ b/share/doc/stabs/Protections.html @@ -0,0 +1,161 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> +<html> +<!-- Copyright (C) 1992-2023 Free Software Foundation, Inc. +Contributed by Cygnus Support. Written by Julia Menapace, Jim Kingdon, +and David MacKenzie. + +Permission is granted to copy, distribute and/or modify this document +under the terms of the GNU Free Documentation License, Version 1.3 or +any later version published by the Free Software Foundation; with no +Invariant Sections, with no Front-Cover Texts, and with no Back-Cover +Texts. A copy of the license is included in the section entitled "GNU +Free Documentation License". --> +<!-- Created by GNU Texinfo 5.1, http://www.gnu.org/software/texinfo/ --> +<head> +<title>STABS: Protections</title> + +<meta name="description" content="STABS: Protections"> +<meta name="keywords" content="STABS: Protections"> +<meta name="resource-type" content="document"> +<meta name="distribution" content="global"> +<meta name="Generator" content="makeinfo"> +<meta http-equiv="Content-Type" content="text/html; charset=utf-8"> +<link href="index.html#Top" rel="start" title="Top"> +<link href="Symbol-Types-Index.html#Symbol-Types-Index" rel="index" title="Symbol Types Index"> +<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents"> +<link href="Cplusplus.html#Cplusplus" rel="up" title="Cplusplus"> +<link href="Method-Modifiers.html#Method-Modifiers" rel="next" title="Method Modifiers"> +<link href="Member-Type-Descriptor.html#Member-Type-Descriptor" rel="previous" title="Member Type Descriptor"> +<style type="text/css"> +<!-- +a.summary-letter {text-decoration: none} +blockquote.smallquotation {font-size: smaller} +div.display {margin-left: 3.2em} +div.example {margin-left: 3.2em} +div.indentedblock {margin-left: 3.2em} +div.lisp {margin-left: 3.2em} +div.smalldisplay {margin-left: 3.2em} +div.smallexample {margin-left: 3.2em} +div.smallindentedblock {margin-left: 3.2em; font-size: smaller} +div.smalllisp {margin-left: 3.2em} +kbd {font-style:oblique} +pre.display {font-family: inherit} +pre.format {font-family: inherit} +pre.menu-comment {font-family: serif} +pre.menu-preformatted {font-family: serif} +pre.smalldisplay {font-family: inherit; font-size: smaller} +pre.smallexample {font-size: smaller} +pre.smallformat {font-family: inherit; font-size: smaller} +pre.smalllisp {font-size: smaller} +span.nocodebreak {white-space:nowrap} +span.nolinebreak {white-space:nowrap} +span.roman {font-family:serif; font-weight:normal} +span.sansserif {font-family:sans-serif; font-weight:normal} +ul.no-bullet {list-style: none} +--> +</style> + + +</head> + +<body lang="en" bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#800080" alink="#FF0000"> +<a name="Protections"></a> +<div class="header"> +<p> +Next: <a href="Method-Modifiers.html#Method-Modifiers" accesskey="n" rel="next">Method Modifiers</a>, Previous: <a href="Member-Type-Descriptor.html#Member-Type-Descriptor" accesskey="p" rel="previous">Member Type Descriptor</a>, Up: <a href="Cplusplus.html#Cplusplus" accesskey="u" rel="up">Cplusplus</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Symbol-Types-Index.html#Symbol-Types-Index" title="Index" rel="index">Index</a>]</p> +</div> +<hr> +<a name="Protections-1"></a> +<h3 class="section">8.9 Protections</h3> + +<p>In the simple class definition shown above all member data and +functions were publicly accessible. The example that follows +contrasts public, protected and privately accessible fields and shows +how these protections are encoded in C<tt>++</tt> stabs. +</p> +<p>If the character following the ‘<samp><var>field-name</var>:</samp>’ part of the +string is ‘<samp>/</samp>’, then the next character is the visibility. ‘<samp>0</samp>’ +means private, ‘<samp>1</samp>’ means protected, and ‘<samp>2</samp>’ means public. +Debuggers should ignore visibility characters they do not recognize, and +assume a reasonable default (such as public) (GDB 4.11 does not, but +this should be fixed in the next GDB release). If no visibility is +specified the field is public. The visibility ‘<samp>9</samp>’ means that the +field has been optimized out and is public (there is no way to specify +an optimized out field with a private or protected visibility). +Visibility ‘<samp>9</samp>’ is not supported by GDB 4.11; this should be fixed +in the next GDB release. +</p> +<p>The following C<tt>++</tt> source: +</p> +<div class="example"> +<pre class="example">class vis { +private: + int priv; +protected: + char prot; +public: + float pub; +}; +</pre></div> + +<p>generates the following stab: +</p> +<div class="example"> +<pre class="example"># <span class="roman">128 is N_LSYM</span> +.stabs "vis:T19=s12priv:/01,0,32;prot:/12,32,8;pub:12,64,32;;",128,0,0,0 +</pre></div> + +<p>‘<samp>vis:T19=s12</samp>’ indicates that type number 19 is a 12 byte structure +named <code>vis</code> The <code>priv</code> field has public visibility +(‘<samp>/0</samp>’), type int (‘<samp>1</samp>’), and offset and size ‘<samp>,0,32;</samp>’. +The <code>prot</code> field has protected visibility (‘<samp>/1</samp>’), type char +(‘<samp>2</samp>’) and offset and size ‘<samp>,32,8;</samp>’. The <code>pub</code> field has +type float (‘<samp>12</samp>’), and offset and size ‘<samp>,64,32;</samp>’. +</p> +<p>Protections for member functions are signified by one digit embedded in +the field part of the stab describing the method. The digit is 0 if +private, 1 if protected and 2 if public. Consider the C<tt>++</tt> class +definition below: +</p> +<div class="example"> +<pre class="example">class all_methods { +private: + int priv_meth(int in){return in;}; +protected: + char protMeth(char in){return in;}; +public: + float pubMeth(float in){return in;}; +}; +</pre></div> + +<p>It generates the following stab. The digit in question is to the left +of an ‘<samp>A</samp>’ in each case. Notice also that in this case two symbol +descriptors apply to the class name struct tag and struct type. +</p> +<div class="display"> +<pre class="display">.stabs "class_name:sym_desc(struct tag&type)type_def(21)= + sym_desc(struct)struct_bytes(1) + meth_name::type_def(22)=sym_desc(method)returning(int); + :args(int);protection(private)modifier(normal)virtual(no); + meth_name::type_def(23)=sym_desc(method)returning(char); + :args(char);protection(protected)modifier(normal)virtual(no); + meth_name::type_def(24)=sym_desc(method)returning(float); + :args(float);protection(public)modifier(normal)virtual(no);;", + N_LSYM,NIL,NIL,NIL +</pre></div> + +<div class="smallexample"> +<pre class="smallexample">.stabs "all_methods:Tt21=s1priv_meth::22=##1;:i;0A.;protMeth::23=##2;:c;1A.; + pubMeth::24=##12;:f;2A.;;",128,0,0,0 +</pre></div> + +<hr> +<div class="header"> +<p> +Next: <a href="Method-Modifiers.html#Method-Modifiers" accesskey="n" rel="next">Method Modifiers</a>, Previous: <a href="Member-Type-Descriptor.html#Member-Type-Descriptor" accesskey="p" rel="previous">Member Type Descriptor</a>, Up: <a href="Cplusplus.html#Cplusplus" accesskey="u" rel="up">Cplusplus</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Symbol-Types-Index.html#Symbol-Types-Index" title="Index" rel="index">Index</a>]</p> +</div> + + + +</body> +</html> |