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diff --git a/share/doc/gdb/dotdebug_005fgdb_005fscripts-section.html b/share/doc/gdb/dotdebug_005fgdb_005fscripts-section.html new file mode 100644 index 0000000..28ce79c --- /dev/null +++ b/share/doc/gdb/dotdebug_005fgdb_005fscripts-section.html @@ -0,0 +1,180 @@ +<!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: dotdebug_gdb_scripts section</title> + +<meta name="description" content="Debugging with GDB: dotdebug_gdb_scripts section"> +<meta name="keywords" content="Debugging with GDB: dotdebug_gdb_scripts section"> +<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="Auto_002dloading-extensions.html#Auto_002dloading-extensions" rel="up" title="Auto-loading extensions"> +<link href="Which-flavor-to-choose_003f.html#Which-flavor-to-choose_003f" rel="next" title="Which flavor to choose?"> +<link href="objfile_002dgdbdotext-file.html#objfile_002dgdbdotext-file" rel="previous" title="objfile-gdbdotext file"> +<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="dotdebug_005fgdb_005fscripts-section"></a> +<div class="header"> +<p> +Next: <a href="Which-flavor-to-choose_003f.html#Which-flavor-to-choose_003f" accesskey="n" rel="next">Which flavor to choose?</a>, Previous: <a href="objfile_002dgdbdotext-file.html#objfile_002dgdbdotext-file" accesskey="p" rel="previous">objfile-gdbdotext file</a>, Up: <a href="Auto_002dloading-extensions.html#Auto_002dloading-extensions" accesskey="u" rel="up">Auto-loading extensions</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="The-_002edebug_005fgdb_005fscripts-section"></a> +<h4 class="subsection">23.5.2 The <code>.debug_gdb_scripts</code> section</h4> +<a name="index-_002edebug_005fgdb_005fscripts-section"></a> + +<p>For systems using file formats like ELF and COFF, +when <small>GDB</small> loads a new object file +it will look for a special section named <code>.debug_gdb_scripts</code>. +If this section exists, its contents is a list of null-terminated entries +specifying scripts to load. Each entry begins with a non-null prefix byte that +specifies the kind of entry, typically the extension language and whether the +script is in a file or inlined in <code>.debug_gdb_scripts</code>. +</p> +<p>The following entries are supported: +</p> +<dl compact="compact"> +<dt><code>SECTION_SCRIPT_ID_PYTHON_FILE = 1</code></dt> +<dt><code>SECTION_SCRIPT_ID_SCHEME_FILE = 3</code></dt> +<dt><code>SECTION_SCRIPT_ID_PYTHON_TEXT = 4</code></dt> +<dt><code>SECTION_SCRIPT_ID_SCHEME_TEXT = 6</code></dt> +</dl> + +<a name="Script-File-Entries"></a> +<h4 class="subsubsection">23.5.2.1 Script File Entries</h4> + +<p>If the entry specifies a file, <small>GDB</small> will look for the file first +in the current directory and then along the source search path +(see <a href="Source-Path.html#Source-Path">Specifying Source Directories</a>), +except that <samp>$cdir</samp> is not searched, since the compilation +directory is not relevant to scripts. +</p> +<p>File entries can be placed in section <code>.debug_gdb_scripts</code> with, +for example, this GCC macro for Python scripts. +</p> +<div class="example"> +<pre class="example">/* Note: The "MS" section flags are to remove duplicates. */ +#define DEFINE_GDB_PY_SCRIPT(script_name) \ + asm("\ +.pushsection \".debug_gdb_scripts\", \"MS\",@progbits,1\n\ +.byte 1 /* Python */\n\ +.asciz \"" script_name "\"\n\ +.popsection \n\ +"); +</pre></div> + +<p>For Guile scripts, replace <code>.byte 1</code> with <code>.byte 3</code>. +Then one can reference the macro in a header or source file like this: +</p> +<div class="example"> +<pre class="example">DEFINE_GDB_PY_SCRIPT ("my-app-scripts.py") +</pre></div> + +<p>The script name may include directories if desired. +</p> +<p>Note that loading of this script file also requires accordingly configured +<code>auto-load safe-path</code> (see <a href="Auto_002dloading-safe-path.html#Auto_002dloading-safe-path">Auto-loading safe path</a>). +</p> +<p>If the macro invocation is put in a header, any application or library +using this header will get a reference to the specified script, +and with the use of <code>"MS"</code> attributes on the section, the linker +will remove duplicates. +</p> +<a name="Script-Text-Entries"></a> +<h4 class="subsubsection">23.5.2.2 Script Text Entries</h4> + +<p>Script text entries allow to put the executable script in the entry +itself instead of loading it from a file. +The first line of the entry, everything after the prefix byte and up to +the first newline (<code>0xa</code>) character, is the script name, and must not +contain any kind of space character, e.g., spaces or tabs. +The rest of the entry, up to the trailing null byte, is the script to +execute in the specified language. The name needs to be unique among +all script names, as <small>GDB</small> executes each script only once based +on its name. +</p> +<p>Here is an example from file <samp>py-section-script.c</samp> in the <small>GDB</small> +testsuite. +</p> +<div class="example"> +<pre class="example">#include "symcat.h" +#include "gdb/section-scripts.h" +asm( +".pushsection \".debug_gdb_scripts\", \"MS\",@progbits,1\n" +".byte " XSTRING (SECTION_SCRIPT_ID_PYTHON_TEXT) "\n" +".ascii \"gdb.inlined-script\\n\"\n" +".ascii \"class test_cmd (gdb.Command):\\n\"\n" +".ascii \" def __init__ (self):\\n\"\n" +".ascii \" super (test_cmd, self).__init__ (" + "\\\"test-cmd\\\", gdb.COMMAND_OBSCURE)\\n\"\n" +".ascii \" def invoke (self, arg, from_tty):\\n\"\n" +".ascii \" print (\\\"test-cmd output, arg = %s\\\" % arg)\\n\"\n" +".ascii \"test_cmd ()\\n\"\n" +".byte 0\n" +".popsection\n" +); +</pre></div> + +<p>Loading of inlined scripts requires a properly configured +<code>auto-load safe-path</code> (see <a href="Auto_002dloading-safe-path.html#Auto_002dloading-safe-path">Auto-loading safe path</a>). +The path to specify in <code>auto-load safe-path</code> is the path of the file +containing the <code>.debug_gdb_scripts</code> section. +</p> +<hr> +<div class="header"> +<p> +Next: <a href="Which-flavor-to-choose_003f.html#Which-flavor-to-choose_003f" accesskey="n" rel="next">Which flavor to choose?</a>, Previous: <a href="objfile_002dgdbdotext-file.html#objfile_002dgdbdotext-file" accesskey="p" rel="previous">objfile-gdbdotext file</a>, Up: <a href="Auto_002dloading-extensions.html#Auto_002dloading-extensions" accesskey="u" rel="up">Auto-loading extensions</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> |