From 132a685299dd6d10bab9792fb2d67be029b8471b Mon Sep 17 00:00:00 2001
From: Jorge Gorbe <j.gorbe@stcsl.es>
Date: Fri, 9 Nov 2012 15:00:15 +0100
Subject: [PATCH] More slides

---
 slides/index.html | 141 ++++++++++++++++++++++++++++++++++++++--------
 1 file changed, 119 insertions(+), 22 deletions(-)

diff --git a/slides/index.html b/slides/index.html
index 968388b..c504e9d 100644
--- a/slides/index.html
+++ b/slides/index.html
@@ -74,9 +74,21 @@
                 <section>
                     <h2> GDB is extensible</h2>
                     <ul>
-                        <li class="fragment"> You can automate things </li>
-                        <li class="fragment"> You can adapt it to your code base </li>
-                        <li class="fragment"> You can try crazy new ideas :D </li>
+                        <li> You can automate things </li>
+                        <li> You can adapt it to your code base </li>
+                        <li> You can try crazy new ideas :D </li>
+                    </ul>
+                </section>
+
+                <section>
+                    <h2>Extension points</h2>
+                    <ul>
+                        <li class="fragment">Pretty printers</li>
+                        <li class="fragment">Custom commands</li>
+                        <li class="fragment">Code auto-loading</li>
+                        <li class="fragment">Event handlers (<code>stop, cont, exited, new_objfile</code>)</li>
+                        <li class="fragment">"Convenience functions"</li>
+                        <li class="fragment">Custom parameters (like "<code>set parameter value</code>", then retrieve values from commands, etc)</li>
                     </ul>
                 </section>
 
@@ -178,32 +190,106 @@ Hello, World!
 
                 <section>
                     <h2>Pretty printing</h2>
-                    <ul>
-                        <li>
-                        Friendly representation of your data structures
-                        </li>
-                        <li>
-                        Up-to-date libc versions have pretty printers for STL containers. You don't need to do
-                        anything to benefit from this RIGHT NOW. <br>
-                        <img class="fragment" src="its-free.jpg">
+                    <p>Friendly representation of your data structures</p>
+<pre class="fragment"><code>(gdb) p m
+$3 = {
+  _M_t = {
+    _M_impl = {
+      <std::allocator<std::_Rb_tree_node<std::pair<std::basic_string<char, std::char_traits<char>, std::allocator<char> > const, int> > >> = {
+        <__gnu_cxx::new_allocator<std::_Rb_tree_node<std::pair<std::basic_string<char, std::char_traits<char>, std::allocator<char> > const, int> > >> = {<No data fields>}, <No data fields>}, 
+      members of std::_Rb_tree<std::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::pair<std::basic_string<char, std::char_traits<char>, std::allocator<char> > const, int>, std::_Select1st<std::pair<std::basic_string<char, std::char_traits<char>, std::allocator<char> > const, int> >, std::less<std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::allocator<std::pair<std::basic_string<char, std::char_traits<char>, std::allocator<char> > const, int> > >::_Rb_tree_impl<std::less<std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, true>: 
+      _M_key_compare = {
+        <std::binary_function<std::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::basic_string<char, std::char_traits<char>, std::allocator<char> >, bool>> = {<No data fields>}, <No data fields>}, 
+      _M_header = {
+        _M_color = std::_S_red, 
+        _M_parent = 0x604120, 
+        _M_left = 0x6040b0, 
+        _M_right = 0x604190
+      }, 
+      _M_node_count = 4
+    }
+  }
+}
+</code></pre>
+                </section>
+                <section>
+                    <h2>Pretty printing</h2>
+                    <p>Friendly representation of your data structures</p>
+<pre><code>(gdb) p m
+$2 = std::map with 4 elements = {
+  ["blah"] = 2,
+  ["lolailo"] = 3,
+  ["trololo"] = 1,
+  ["xyz"] = 4
+}
+</code></pre>
+                </section>
+                <section>
+                    <h2>Pretty printing</h2>
+                    <p>
+                    Up-to-date libc versions have pretty printers for STL containers. You don't need to do
+                    anything to benefit from this RIGHT NOW.
+                    </p>
 
-                        </li>
-                    </ul>
+                    <img class="fragment" src="its-free.jpg">
+                </section>
+
+                <section>
+                    <section>
+                        <h2>Pretty printing</h2>
+                        <p>
+                        Of course, you can do it for your own data structures too:
+                        <a href="http://sourceware.org/gdb/onlinedocs/gdb/Writing-a-Pretty_002dPrinter.html#Writing-a-Pretty_002dPrinter">Writing a pretty printer</a>
+                        </p>
+                    </section>
+
+                    <section>
+                        <h2>Pretty printer implementation</h2>
+                        <p>You need to define a class...</p>
+<pre><code>class StdStringPrinter(object):
+    "Print a std::string"
+     
+    def __init__(self, val):
+        self.val = val
+     
+    def to_string(self):
+        return self.val['_M_dataplus']['_M_p']
+     
+    def display_hint(self):
+        return 'string'
+</code></pre>
+                    </section>
+
+                    <section>
+                        <h2>Pretty printer implementation</h2>
+                        <p>... and a lookup function</p>
+<pre><code>def str_lookup_function(val):
+    lookup_tag = val.type.tag
+    if lookup_tag == None:
+        return None
+    regex = re.compile("^std::basic_string<char,.*>$")
+    if regex.match(lookup_tag):
+        return StdStringPrinter(val)
+    return None
+</code></pre>
+                        <p class="fragment">And then do some boring stuff to register it into gdb</p>
+                    </section>
 
                 </section>
 
                 <section>
                     <h2>Custom commands (python version)</h2>
-<pre><code>
+<pre><code> # create a class for your new command
 class DoNothingCommand(gdb.Command):
-    """This command does nothing."""  # docstring
+    """This command does nothing."""  # docstring (shown by gdb help command)
     def __init__(self):
-        super(DoNothingCommand, self).__init__("do_nothing", gdb.COMMAND_USER, gdb.COMPLETE_NONE)
-
+        super(DoNothingCommand, self).__init__("do_nothing",
+                                               gdb.COMMAND_USER,
+                                               gdb.COMPLETE_NONE)
     def invoke(self, arg, from_tty):
         pass
 
-DoNothingCommand()
+DoNothingCommand() # and instance it
 
 </code></pre>
                 </section>
@@ -223,15 +309,26 @@ DoNothingCommand()
 
                 <section>
                     <h2>Wish list</h2>
-                    <p>Other debuggers also have cool features</p>
-                    <ul style="text-align:left;">
-                        <li> <h3>Symbol server support</h3> records (some finite amount of) program history and allows backwards stepping/running.  </li>
+                    <ul>
+                        <li> 
+                        <b>Symbol and source server support</b><br>
+                        Central store for symbols of every build, so you can always retrieve the correct version automatically
+                        without distributing debug info to users. Also, integration with SCM to retrieve the matching source code.
+                        See <a href="http://randomascii.wordpress.com/2011/11/11/source-indexing-is-underused-awesomeness/">Bruce Dawson's great post</a>
+                        </li>
                     </ul>
                 </section>
 
                 <section>
                     <h2>Resources</h2>
-                    <p> <a href="http://sourceware.org/gdb/wiki/PythonGdbTutorial">http://sourceware.org/gdb/wiki/PythonGdbTutorial</a> </p>
+                    <ul>
+                    <li> <a href="http://sourceware.org/gdb/wiki/PythonGdbTutorial">http://sourceware.org/gdb/wiki/PythonGdbTutorial</a></li>
+                    <li> <a href="http://en.wikibooks.org/wiki/Linux_Applications_Debugging_Techniques">http://en.wikibooks.org/wiki/Linux_Applications_Debugging_Techniques</a></li>
+                </section>
+
+                <section>
+                    <h1>Thanks!</h1>
+                    <h2>Questions?</h2>
                 </section>
 
                 <!-- End slides. -->
-- 
2.34.1