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Rework discussion of untar and build.

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Bradley M. Kuhn 2014-11-07 09:09:46 -05:00
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enforcement-case-studies.tex
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@ -402,56 +402,75 @@ require a very specific host system. Even in this case, a
\hyperref[thinkpenguin-glibc-214-issue]{minor annoyance was found that more \hyperref[thinkpenguin-glibc-214-issue]{minor annoyance was found that more
detailed instructions would address}. detailed instructions would address}.
* The actual building of the source code was completed in the following way: Anyway, since these instructions did not specify a specific host system, the
** Since the instructions didn't mention a specific distro to use, we ran the investigator simply used his own amd64 Debian 6 desktop system. Before
build on an amd64 Debian 6 machine we had. The only distro requirement was: beginning, the investigator used the following command:
To build your own firmware you need to have access to a GNU/Linux system \lstset{tabsize=2}
(case-sensitive filesystem required). \begin{lstlisting}[language=bash]
$ dpkg --list | egrep '^iii' | less
\end{lstlisting}
** The README mentioned that: to verify that the required packages listed in the README were
installed\footnote{The \verb0dpkg0 command is a Debian-specific way of
finding installed packages.}.
"In order to build firmware images for your router,the
following needs to be installed :
gcc, binutils, bzip2, flex, python, perl, make, find, Next, the investigator then extracted the primary source package with the
grep, diff, unzip, gawk, getopt, libz-dev and libc headers." following command:
So we ran "dpkg --list" and confirmed that each package was installed (this \lstset{tabsize=2}
is indicated by a leading "ii" on the line containing the package). Other \begin{lstlisting}[language=bash]
GNU/Linux distributions may have other ways of determing which packages are $ tar --posix -jxpf libCMC/librecmc-v1.2.1.tar.bz2
installed. \end{lstlisting}
** We then extracted the LibreCMC tarball by running
"tar --posix -jxpf /media/libreCMC\verb0_0v1\verb0_02\verb0_01\verb0_0SRC/librecmc-v1.2.1.tar.bz2". The
CD did contain another tarball (librecmc-u-boot.tar.bz2), but there appeared
to be separate instructions for that (in the u-boot\verb0_0reflash text file in the
same directory). Having the README be more explicit about this would be nice
but did not ultimately prevent us from determing the proper steps to execute.
** The README mentioned the following optional step, which we skipped because
we did not need to modify the configuration for our initial build:
Please use "make menuconfig" to configure your appreciated The investigator did notice an additional source release, entitled
configuration for the toolchain and firmware. Please note that ``librecmc-u-boot.tar.bz2''. The investigator concluded upon simple
the default configuration is what was used to build the firmware inspection that the instructions found in ``u-boot\verb0_0reflash'' were
image for your router. It is advised that you use this configuration. specific instructions for that part of the CCS\@. This was a minor
annoyance, and ideally the ``README'' would list that fact, but the existing
layout met the reasonable standard that community-oriented GPL enforcers
typically apply, since the skilled investigator could determine the correct
course of action with a few moments of study.
** The next instruction was 'Simply running "make" will build your firmware.' The investigator then noted the additional step offered by the ``README'',
So we entered the "librecmc" directory that had been created from the above which read:
"tar" command and then ran "make". The build took about 40 minutes to run on \begin{quotation}
our system. The command used and output from running it are available here: Please use ``make menuconfig'' to configure your appreciated configuration
for the toolchain and firmware. Please note that the default configuration is
what was used to build the firmware image for your router. It is advised that
you use this configuration.
\end{quotation}
enforcement-case-studies\verb0_0log-output/thinkpenguin\verb0_0librecmc-complete.log This instruction actually goes above and beyond the requirements of GPL\@.
Specifically, the instruction guides users in their first step toward
exercising the freedom to modify the software. While the GPL does contain
requirements that facility the freedom to modify (such as ensuring the CCS is
in the ``preferred form \hellip for making modifications to it'' form, it
does not require that you write specific instructions explaining how
modifications might be undertaken. This instruction therefore exemplifies
the exceptional quality of this particular CCS\@.
% FIXME: Above, I'd like to see more ``walk through'' of the step by step %FIXME: add a \hyperref to some ``preferred for for modification'' stuff above.
% instructions. The text is a bit terse: could be expanded to talk more.
% FIXME(dg): Hopefully the above will suffice. I can expand more/differently if
% such is desired.
* It was helpful to know that we could use "make menuconfig" for configuration However, for purposes of the CCS verification process, typically the
changes, as being able to modify the source is an important part of the GPL's investigator avoids any unnecessary changes to the source code during the
requirements. Adding instructions like these shows that the distributor is build process, lest the investigator err and cause the build to fail through
aware of and interested in promoting the spirit of the GPL, by making it his own modification, and thus incorrectly identify the CCS as inadequate.
easier to modify the source than may be strictly required by the GPL's text. Therefore, the investigator proceeded to simply run:
\lstset{tabsize=2}
\begin{lstlisting}[language=bash]
$ cd libCMC
$ make
\end{lstlisting}
and waited approximately 40 minutes for the build to complete\footnote{Build
times will likely vary widely on various host systems}. The investigator
kept a
\href{https://gitorious.org/copyleft-org/tutorial/source/master:enforcement-case-studies_log-output/thinkpenguin_librecmc-complete.log}{full
log of the build}, which is not included herein due its size (approximately
7.2K of text).
% FIXME: We should somewhere (perhaps on each step we discuss) talk about % FIXME: We should somewhere (perhaps on each step we discuss) talk about
% what often goes wrong on those steps, and why this is right. As written % what often goes wrong on those steps, and why this is right. As written