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diff --git a/share/doc/gdb/GDB_002fMI-Commands-In-Python.html b/share/doc/gdb/GDB_002fMI-Commands-In-Python.html new file mode 100644 index 0000000..654593a --- /dev/null +++ b/share/doc/gdb/GDB_002fMI-Commands-In-Python.html @@ -0,0 +1,228 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> +<html> +<!-- Copyright (C) 1988-2023 Free Software Foundation, Inc. + +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 the +Invariant Sections being "Free Software" and "Free Software Needs +Free Documentation", with the Front-Cover Texts being "A GNU Manual," +and with the Back-Cover Texts as in (a) below. + +(a) The FSF's Back-Cover Text is: "You are free to copy and modify +this GNU Manual. Buying copies from GNU Press supports the FSF in +developing GNU and promoting software freedom." --> +<!-- Created by GNU Texinfo 5.1, http://www.gnu.org/software/texinfo/ --> +<head> +<title>Debugging with GDB: GDB/MI Commands In Python</title> + +<meta name="description" content="Debugging with GDB: GDB/MI Commands In Python"> +<meta name="keywords" content="Debugging with GDB: GDB/MI Commands In Python"> +<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="Concept-Index.html#Concept-Index" rel="index" title="Concept Index"> +<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents"> +<link href="Python-API.html#Python-API" rel="up" title="Python API"> +<link href="Parameters-In-Python.html#Parameters-In-Python" rel="next" title="Parameters In Python"> +<link href="CLI-Commands-In-Python.html#CLI-Commands-In-Python" rel="previous" title="CLI Commands In Python"> +<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="GDB_002fMI-Commands-In-Python"></a> +<div class="header"> +<p> +Next: <a href="Parameters-In-Python.html#Parameters-In-Python" accesskey="n" rel="next">Parameters In Python</a>, Previous: <a href="CLI-Commands-In-Python.html#CLI-Commands-In-Python" accesskey="p" rel="previous">CLI Commands In Python</a>, Up: <a href="Python-API.html#Python-API" accesskey="u" rel="up">Python API</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html#Concept-Index" title="Index" rel="index">Index</a>]</p> +</div> +<hr> +<a name="GDB_002fMI-Commands-In-Python-1"></a> +<h4 class="subsubsection">23.3.2.21 <small>GDB/MI</small> Commands In Python</h4> + +<a name="index-MI-commands-in-python"></a> +<a name="index-commands-in-python_002c-GDB_002fMI"></a> +<a name="index-python-commands_002c-GDB_002fMI"></a> +<p>It is possible to add <small>GDB/MI</small> (see <a href="GDB_002fMI.html#GDB_002fMI">GDB/MI</a>) commands +implemented in Python. A <small>GDB/MI</small> command is implemented using an +instance of the <code>gdb.MICommand</code> class, most commonly using a +subclass. +</p> +<dl> +<dt><a name="index-MICommand_002e_005f_005finit_005f_005f"></a>Function: <strong>MICommand.__init__</strong> <em>(name)</em></dt> +<dd><p>The object initializer for <code>MICommand</code> registers the new command +with <small>GDB</small>. This initializer is normally invoked from the +subclass’ own <code>__init__</code> method. +</p> +<p><var>name</var> is the name of the command. It must be a valid name of a +<small>GDB/MI</small> command, and in particular must start with a hyphen +(<code>-</code>). Reusing the name of a built-in <small>GDB/MI</small> is not +allowed, and a <code>RuntimeError</code> will be raised. Using the name +of an <small>GDB/MI</small> command previously defined in Python is allowed, the +previous command will be replaced with the new command. +</p></dd></dl> + +<dl> +<dt><a name="index-MICommand_002einvoke"></a>Function: <strong>MICommand.invoke</strong> <em>(arguments)</em></dt> +<dd><p>This method is called by <small>GDB</small> when the new MI command is +invoked. +</p> +<p><var>arguments</var> is a list of strings. Note, that <code>--thread</code> +and <code>--frame</code> arguments are handled by <small>GDB</small> itself therefore +they do not show up in <code>arguments</code>. +</p> +<p>If this method raises an exception, then it is turned into a +<small>GDB/MI</small> <code>^error</code> response. Only <code>gdb.GdbError</code> +exceptions (or its sub-classes) should be used for reporting errors to +users, any other exception type is treated as a failure of the +<code>invoke</code> method, and the exception will be printed to the error +stream according to the <kbd>set python print-stack</kbd> setting +(see <a href="Python-Commands.html#set_005fpython_005fprint_005fstack"><kbd>set python print-stack</kbd></a>). +</p> +<p>If this method returns <code>None</code>, then the <small>GDB/MI</small> command will +return a <code>^done</code> response with no additional values. +</p> +<p>Otherwise, the return value must be a dictionary, which is converted +to a <small>GDB/MI</small> <var>result-record</var> (see <a href="GDB_002fMI-Output-Syntax.html#GDB_002fMI-Output-Syntax">GDB/MI Output Syntax</a>). +The keys of this dictionary must be strings, and are used as +<var>variable</var> names in the <var>result-record</var>, these strings must +comply with the naming rules detailed below. The values of this +dictionary are recursively handled as follows: +</p> +<ul> +<li> If the value is Python sequence or iterator, it is converted to +<small>GDB/MI</small> <var>list</var> with elements converted recursively. + +</li><li> If the value is Python dictionary, it is converted to +<small>GDB/MI</small> <var>tuple</var>. Keys in that dictionary must be strings, +which comply with the <var>variable</var> naming rules detailed below. +Values are converted recursively. + +</li><li> Otherwise, value is first converted to a Python string using +<code>str ()</code> and then converted to <small>GDB/MI</small> <var>const</var>. +</li></ul> + +<p>The strings used for <var>variable</var> names in the <small>GDB/MI</small> output +must follow the following rules; the string must be at least one +character long, the first character must be in the set +<code>[a-zA-Z]</code>, while every subsequent character must be in the set +<code>[-_a-zA-Z0-9]</code>. +</p></dd></dl> + +<p>An instance of <code>MICommand</code> has the following attributes: +</p> +<dl> +<dt><a name="index-MICommand_002ename"></a>Variable: <strong>MICommand.name</strong></dt> +<dd><p>A string, the name of this <small>GDB/MI</small> command, as was passed to the +<code>__init__</code> method. This attribute is read-only. +</p></dd></dl> + +<dl> +<dt><a name="index-MICommand_002einstalled"></a>Variable: <strong>MICommand.installed</strong></dt> +<dd><p>A boolean value indicating if this command is installed ready for a +user to call from the command line. Commands are automatically +installed when they are instantiated, after which this attribute will +be <code>True</code>. +</p> +<p>If later, a new command is created with the same name, then the +original command will become uninstalled, and this attribute will be +<code>False</code>. +</p> +<p>This attribute is read-write, setting this attribute to <code>False</code> +will uninstall the command, removing it from the set of available +commands. Setting this attribute to <code>True</code> will install the +command for use. If there is already a Python command with this name +installed, the currently installed command will be uninstalled, and +this command installed in its place. +</p></dd></dl> + +<p>The following code snippet shows how a two trivial MI command can be +implemented in Python: +</p> +<div class="smallexample"> +<pre class="smallexample">class MIEcho(gdb.MICommand): + """Echo arguments passed to the command.""" + + def __init__(self, name, mode): + self._mode = mode + super(MIEcho, self).__init__(name) + + def invoke(self, argv): + if self._mode == 'dict': + return { 'dict': { 'argv' : argv } } + elif self._mode == 'list': + return { 'list': argv } + else: + return { 'string': ", ".join(argv) } + + +MIEcho("-echo-dict", "dict") +MIEcho("-echo-list", "list") +MIEcho("-echo-string", "string") +</pre></div> + +<p>The last three lines instantiate the class three times, creating three +new <small>GDB/MI</small> commands <code>-echo-dict</code>, <code>-echo-list</code>, and +<code>-echo-string</code>. Each time a subclass of <code>gdb.MICommand</code> is +instantiated, the new command is automatically registered with +<small>GDB</small>. +</p> +<p>Depending on how the Python code is read into <small>GDB</small>, you may +need to import the <code>gdb</code> module explicitly. +</p> +<p>The following example shows a <small>GDB</small> session in which the above +commands have been added: +</p> +<div class="smallexample"> +<pre class="smallexample">(gdb) +-echo-dict abc def ghi +^done,dict={argv=["abc","def","ghi"]} +(gdb) +-echo-list abc def ghi +^done,list=["abc","def","ghi"] +(gdb) +-echo-string abc def ghi +^done,string="abc, def, ghi" +(gdb) +</pre></div> + +<hr> +<div class="header"> +<p> +Next: <a href="Parameters-In-Python.html#Parameters-In-Python" accesskey="n" rel="next">Parameters In Python</a>, Previous: <a href="CLI-Commands-In-Python.html#CLI-Commands-In-Python" accesskey="p" rel="previous">CLI Commands In Python</a>, Up: <a href="Python-API.html#Python-API" accesskey="u" rel="up">Python API</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html#Concept-Index" title="Index" rel="index">Index</a>]</p> +</div> + + + +</body> +</html> |