From 0c7350ff959e26475ae600c2a1f7fb211117f035 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Th=C3=A9ophile=20Bastian?= <contact@tobast.fr>
Date: Fri, 17 Aug 2018 20:38:20 +0200
Subject: [PATCH] Add reference to git.tobast.fr

---
 report/report.tex | 44 ++++++++++++++++++++++++++++++++------------
 1 file changed, 32 insertions(+), 12 deletions(-)

diff --git a/report/report.tex b/report/report.tex
index 03e3d93..ef5c672 100644
--- a/report/report.tex
+++ b/report/report.tex
@@ -55,8 +55,8 @@ Under supervision of Francesco Zappa-Nardelli\\
 \subsection*{Source code}\label{ssec:source_code}
 
 The source code of all the implementations made during this internship is
-available at \url{https://git.tobast.fr/m2-internship/} under free software
-licenses, in various repositories.
+available at \url{https://git.tobast.fr/m2-internship/}. See
+Section~\ref{ssec:code_avail} for details.
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -679,6 +679,16 @@ The tentative approach that was chosen to try to get better unwinding speeds at
 a reasonable space loss was to compile directly the \ehframe{} into native
 machine code on the x86\_64 platform.
 
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+\subsection{Code availability}\label{ssec:code_avail}
+
+All the code produced during this internship is available on the various
+repositories from \url{https://git.tobast.fr/m2-internship/}. The repositories
+contain \texttt{README} files describing them; a summary and global description
+can be found in the \texttt{abstract} repository. This should be detailed
+enough to run the project. The source code is entirely under free software
+licenses.
+
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 \subsection{Compilation: \ehelfs}\label{ssec:ehelfs}
 
@@ -748,6 +758,16 @@ imagine, in a future environment production, packaging \ehelfs{} files
 separately, so that people interested in heavy computation can have the choice
 to install them.
 
+This, in particular, means that each ELF file has its unwinding data in a
+separate \ehelf{} file --~just like with DWARF, where each ELF retains its own
+DWARF data. Thus, an unwinder must first acquire a \emph{memory map}, a table
+listing the various ELF files loaded and \emph{mapped} in memory, and on which
+memory segment. This memory map is provided by the operating system --~for
+instance, on Linux, it is available as a file in \texttt{/proc}. Once this map
+is acquired, when unwinding from a given IP, the unwinder must identify the
+memory segment from which it comes, deduce the source ELF file, and deduce the
+corresponding \ehelf.
+
 \medskip
 
 \lstinputlisting[language=C, caption={\ehelf{} for the previous example},
@@ -922,14 +942,13 @@ Interfacing \ehelfs{} with \prog{perf} required, in a first place, to fork
 turned out necessary to slightly modify \prog{libunwind}'s interface to add a
 parameter to an initialisation function, since \prog{libunwind} is made to be
 agnostic of the system and process as much as possible, to be able to unwind in
-any context.  This very restricted information lacked a \emph{memory map}, a
-table indicating which shared object is mapped at which address in memory, in
-order to use \ehelfs. Apart from this, the modified version of \prog{libunwind}
-produced is entirely compatible with the vanilla version. This means that the
-only modifications required to use \ehelfs{} within any project using
-\prog{libunwind} should be changing one line of code to add one parameter to a
-function call and linking against the modified version of \prog{libunwind}
-instead of the system version.
+any context.  This very restricted information lacked a memory map (see
+Section~\ref{ssec:ehelfs}) in order to use \ehelfs. Apart from this, the
+modified version of \prog{libunwind} produced is entirely compatible with the
+vanilla version. This means that the only modifications required to use
+\ehelfs{} within any project using \prog{libunwind} should be changing one line
+of code to add one parameter to a function call and linking against the
+modified version of \prog{libunwind} instead of the system version.
 
 Once this was done, plugging it in \prog{perf} was the matter of a few lines of
 code only, left apart the benchmarking code. The major problem encountered was
@@ -1212,8 +1231,9 @@ some unsupported instruction at all.
 \hfill \begin{minipage}{0.7\textwidth}
     \begin{flushright}
         \itshape{} \small{}
-        Unless otherwise explicitly stated, any image, source code snippet or
-        table from the present document can be reused freely by anyone.
+        Unless otherwise explicitly stated, any image from the present document
+        is distributed under Creative Commons BY-SA license, and any code
+        snippet is distributed under 3-clause BSD license.
     \end{flushright}
 \end{minipage}