.. _chapter-patching-spkgs: ======================= Patching a Sage Package ======================= This chapter provides guidelines on patching an existing spkg. Also covered are steps for upgrading an upstream project's source distribution, as contained under the subdirectory ``src/``, to the latest upstream release. For information on creating a new spkg, see the chapter :ref:`chapter-spkg`. .. _section-spkg-patching-overview: Overview of patching spkg's =========================== Make sure you are familiar with the structure and conventions relating to spkg's; see the chapter :ref:`chapter-spkg` for details. Patching an spkg involves patching the installation script of the spkg and/or patching the upstream source code contained in the spkg. Say you want to patch the Matplotlib package ``matplotlib-1.0.1.p0``. Note that "p0" denotes the patch level of the spkg, while "1.0.1" refers to the upstream version of Matplotlib as contained under ``matplotlib-1.0.1.p0/src/``. The installation script of that spkg is :: matplotlib-1.0.1.p0/spkg-install In general, a script with the name ``spkg-install`` is an installation script for an spkg. To patch the installation script, use a text editor to edit that script. Then in the log file ``SPKG.txt``, provide a high-level description of your changes. Once you are satisfied with your changes in the installation script and the log file ``SPKG.txt``, use Mercurial to check in your changes and make sure to provide a meaningful commit message. See the section :ref:`section-submitting-change` for guidelines relating to commit messages. The directory ``src/`` contains the source code provided by the upstream project. For example, the source code of Matplotlib 1.0.1 is contained under :: matplotlib-1.0.1.p0/src/ To patch the upstream source code, you should edit a copy of the relevant file -- files in the ``src/`` directory should be untouched, "vanilla" versions of the source code. For example, you might copy the entire ``src/`` directory:: $ pwd matplotlib-1.0.1.p0 $ cp -pR src src-patched Then edit files in ``src-patched/``. Once you are satisfied with your changes, generate a unified diff between the original file and the edited one, and save it in ``patches/``:: $ diff -u src/configure src-patched/configure > patches/configure.patch Save the unified diff to a file with the same name as the source file you patched, but using the file extension ".patch". Note that the directory ``src/`` should not be under revision control, whereas ``patches/`` must be under revision control. The Mercurial configuration file ``.hgignore`` should contain the following line:: src/ Ensure that the installation script ``spkg-install`` contains code to apply the patches to the relevant files under ``src/``. For example, the file :: matplotlib-1.0.1.p0/patches/finance.py.patch is a patch for the file :: matplotlib-1.0.1.p0/src/lib/matplotlib/finance.py The installation script ``matplotlib-1.0.1.p0/spkg-install`` contains the following code to install the relevant patches:: cd src # Apply patches. See SPKG.txt for information about what each patch # does. for patch in ../patches/*.patch; do patch -p1 <"$patch" if [ $? -ne 0 ]; then echo >&2 "Error applying '$patch'" exit 1 fi done Of course, this could be modified if the order in which the patches are applied is important, or if some patches were platform-dependent. For example:: if [ "$UNAME" = "Darwin" ]; then for patch in ../patches/darwin/*.patch; do patch -p1 <"$patch" if [ $? -ne 0 ]; then echo >&2 "Error applying '$patch'" exit 1 fi done fi (The environment variable :envvar:`UNAME` is defined by the script ``sage-env``, and is available when ``spkg-install`` is run.) Now provide a high-level explanation of your changes in ``SPKG.txt``. Note the format of ``SPKG.txt`` -- see the chapter :ref:`chapter-spkg` for details. Once you are satisfied with your changes, use Mercurial to check in your changes with a meaningful commit message. Then use the command ``hg tag`` to tag the tip with the new version number (using "p1" instead of "p0": we have made changes, so we need to update the patch level):: $ hg tag matplotlib-1.0.1.p1 Next, rename the directory ``matplotlib-1.0.1.p0`` to ``matplotlib-1.0.1.p1`` to match the new patch level. To produce the actual spkg file, change to the parent directory of ``matplotlib-1.0.1.p1`` and execute :: $ /path/to/sage-x.y.z/sage --pkg matplotlib-1.0.1.p1 Creating Sage package matplotlib-1.0.1.p1 Created package matplotlib-1.0.1.p1.spkg. NAME: matplotlib VERSION: 1.0.1.p1 SIZE: 11.8M HG REPO: Good SPKG.txt: Good Spkg files are either bzipped tar files or just plain tar files; the command ``sage --pkg ...`` produces the bzipped version. If your spkg contains mostly binary files which will not compress well, you can use ``sage --pkg_nc ...`` to produce an uncompressed version, i.e., a plain tar file:: $ sage --pkg_nc matplotlib-1.0.1.p0/ Creating Sage package matplotlib-1.0.1.p0/ with no compression Created package matplotlib-1.0.1.p0.spkg. NAME: matplotlib VERSION: 1.0.1.p0 SIZE: 32.8M HG REPO: Good SPKG.txt: Good Note that this is almost three times the size of the compressed version, so we should use the compressed version! At this point, you might want to submit your patched spkg for review. So provide a URL to your spkg on the relevant trac ticket and/or in an email to the relevant mailing list. Usually, you should not upload your spkg itself to the relevant trac ticket -- don't post large binary files to the trac server. Use patch for patching ====================== The main message of this section is: use the GNU program ``patch`` to apply patches to files in ``src/``. GNU patch is distributed with Sage, so if you are writing an spkg which is not part of the standard Sage distribution, you may use ``patch`` in the ``spkg-install`` script freely. If you are working on an spkg which is (or will be) a standard spkg in Sage, then you should make sure that ``patch`` is listed as a dependency for your spkg in the makefile ``SAGE_ROOT/spkg/standard/deps``. See the section :ref:`section-spkg-patching-overview` for information about how to produce patch files in the directory ``patches/``, and how to apply them in ``spkg-install``. Bumping up an spkg's version ============================ If you want to bump up the version of an spkg, you need to follow some naming conventions. Use the name and version number as given by the upstream project, e.g. ``matplotlib-1.0.1``. If the upstream package is taken from some revision other than a stable version, you need to append the date at which the revision is made, e.g. the Singular package ``singular-3-1-0-4-20090818.p3.spkg`` is made with the revision as of 2009-08-18. If you start afresh from an upstream release without any patches to its source code, the resulting spkg need not have any patch-level labels (appending ".p0" is allowed, but is optional). For example, ``sagenb-0.6.spkg`` is taken from the upstream stable version ``sagenb-0.6`` without any patches applied to its source code. So you do not see any patch-level numbering such as ``.p0`` or ``.p1``. Say you start with ``matplotlib-1.0.1.p0`` and you want to replace Matplotlib 1.0.1 with version 1.0.2. This entails replacing the source code for Matplotlib 1.0.1 under ``matplotlib-1.0.1.p0/src/`` with the new source code. To start with, follow the naming conventions as described in the section :ref:`section-spkg-patching-overview`. If necessary, remove any obsolete patches and create any new ones, placing them in the ``patches/`` directory. Modify the script ``spkg-install`` to take any changes to the patches into account; you might also have to deal with changes to how the new version of the source code builds. Then package your replacement spkg using the Sage command line options ``--pkg`` or ``--pkg_nc`` (or tar and bzip2). To install your replacement spkg, you use :: sage -f http://URL/to/package-x.y.z.spkg or :: sage -f /path/to/package-x.y.z.spkg To compile Sage from source with the replacement (standard) spkg, untar a Sage source tarball, remove the existing spkg under ``SAGE_ROOT/spkg/standard/``. In its place, put your replacement spkg. Then execute ``make`` from ``SAGE_ROOT``.