NAME
dpatch - patch maintenance system for Debian
SYNOPSIS
dpatch [options] command [command-arguments]
DESCRIPTION
dpatch is an easy to use patch system for Debian packages, somewhat
similar to the dbs package, but much simpler to use.
It lets you store patches and other simple customization templates in
debian/patches and otherwise does not require much reorganization of
your source tree. To get the patches applied at build time you simply
need to include a makefile snippet and then depend on the patch/unpatch
target in the build or clean stage of debian/rules. For added
flexibility, you can call /usr/bin/dpatch directly too.
GLOBAL OPTIONS
There are a few options which change the overall behaviour of dpatch,
and have an effect on not only one, but most of the available commands.
These global options are:
--workdir (-d) DIRECTORY
By default, dpatch applies patches to the source tree it was run
from. With this option, one can change that, and tell dpatch to
work on a different tree, although taking the dpatches from the
current one.
Note that this will only pass a second argument to dpatch
scriptlets, and will not change to the specified directory. To
do that, use the --chdir option explained below.
--chdir (-c)
When using a different working directory than the current one,
change there before trying to apply patches.
This should be used together with the --workdir option.
--strict (-S)
Enable strict mode, which means that dpatch will bail out early
even on warnings (like when trying to apply a patch which is
already applied - normally it will simply skip it).
--force (-F)
Force the application or deapplication of patches, even if
dpatch would normally skip them because the operation was
already done earlier.
--with-cpp
Force the use of cpp. Overrides use of DPATCH_OPTION_CPP=1
option in debian/patches/00options file.
COMMANDS
Patch handling commands
There is a generic syntax for all patch handling commands, namely that,
that the command itself takes a list of dpatch names to work with, then
does what it is meant to do on all of them, in the exact same order it
was specified on the command line.
Then, there is a version of each patch handling command with an -all
suffix, which does not take any arguments, and performs the necessary
action for each and every available dpatch.
The last variation is a command with a -until or -up-to suffix, which
takes only one argument: the name of a dpatch. The appropriate action
will be performed on all dpatches up to and including this specified
one.
apply (patch) [options]
Applies one or more dpatches to the working tree (the current
directory, if not told otherwise). By default the specified
patches will be applied in the exact same order they were
specified.
Options
--stampdir=directory, -s=directory
Put stamp files into directory instead of the
default debian/patched.
--help (-h)
Print a short help message about the command.
--quiet (-q)
Forces the command to not print anything.
--verbose (-v)
Disables hiding of the scriptlet output.
deapply (unpatch) [options]
Deapplies one or more dpatches to the working tree (the current
directory, if not told otherwise). By default the specified
patches will be deapplied in the reverse order they were
specified as one generally should deapply in reverse order
(compared to the apply order, that is).
Options
--stampdir=directory, -s=directory
Use stamp files in directory instead of the
default debian/patched.
--help (-h)
Print a short help message about the command.
--quiet (-q)
Forces the command to not print anything.
--verbose (-v)
Disables hiding of the scriptlet output.
cat [options]
Print meta-information about a dpatch, such as its name, author
and description (any of which can be disabled with the
appropriate option).
Options
--no-meta, --desc-only (-nm, -d)
Only print the patch description.
--author-only (-a)
Only print the author of the patch.
--no-desc, (-nd)
Do not print the patch description.
--help (-h)
Print a short help message about the command.
--quiet (-q)
Forces the command to not print anything.
list [options]
List the name of the given patches. This commands is not really
useful, except the list-all variant, which lists all available
patches.
Options
--help (-h)
Print a short help message about the command.
status [options]
Prints the status of the given patches - whether they are
applied to the working tree or not.
Options
--stampdir=directory, -s=directory
Use stamp files in directory instead of the
default debian/patched.
--help (-h)
Print a short help message about the command.
--quiet (-q)
Forces the command to not print anything.
log [options]
Displays the log of the given patching attempts.
Options
--stampdir=directory, -s=directory
Use stamp files in directory instead of the
default debian/patched.
--help (-h)
Print a short help message about the command.
--quiet (-q)
Forces the command to not print anything, but the
logs without extra sugar on top.
call [options]
Call a dpatch with a user-specified argument. All arguments with
a pkg- prefix is guaranteed to be unused by dpatch itself, and
are reserved for use with this very command.
This command is most useful for extracting custom
meta-information from dpatch scriptlets.
Options
--argument=arg (-a=arg)
Call patches with arg as argument.
--help (-h)
Print a short help message about the command.
--quiet (-q)
Forces the command to not print anything.
Miscellaneous commands
patch-template [options] [patchname] [description]
Print a quasi-standard dpatch script template, based on the
information give on the command-line. If a description given, it
will be folded at about 72 characters into multiple lines
appropriately.
When prepending the template to STDIN, the contents of the
standard input will be printed right after the template.
Options
--prepend (-p)
Prepend the template to STDIN.
--help (-h)
Print a short help message about the command.
help (--help, -h) [command]
Attempt to give a little more detailed help about dpatch itself,
or about a given dpatch command.
version
Prints the dpatch version number and exits.
DPATCH IN DEBIAN PACKAGES
There are two different ways to use dpatch in debian/rules: calling it
directly, or including dpatch.make(7). Only the former method will be
described here - the latter has its own manual page.
NOTE: The following examples also require adding the .NOTPARALLEL flag
to the head of debian/rules since the dependency lists rely on the
order of the execution. Without .NOTPARALLEL, they execution order may
be wrong with multiple make threads (the -j option).
In most situations, one will want to run dpatch as soon during the
build process, as possible. How that can be accomplished depends
heavily on the existing debian/rules. However, in common practice most
packages have a build (or build-stamp), config.status, or configure (or
configure-stamp) target. The easiest way to make dpatching the very
first thing, one only has to write a rule that calls dpatch, and add it
to the list of prerequisites for the appropriate target (see above).
Deapplying dpatches can be easy or a bit more tricky. If nothing in the
clean rule touches files modified by dpatches (creating incompatible
changes), you can safely add unpatch to the list of the clean rules
dependencies.
If the patches might affect the build system, they should be deapplied
after the source tree has been cleaned. To do this, rename the clean
target to, say, clean-patched, write a rule that calls dpatch to
deapply the dpatches, and make a new clean rule that has clean-patched
and unpatch as its prerequisites.
Let us look at an example! First, let us look at the relevant parts of
the original debian/rules of our imaginary package:
config.status: configure
./configure --prefix=/usr --mandir=/usr/share
build: config.status
${MAKE}
clean:
$(testdir)
$(testroot)
${MAKE} distclean
rm -rf debian/imaginary-package debian/files debian/substvars
After dpatchifying, this would look like this:
config.status: patch configure
./configure --prefix=/usr --mandir=/usr/share
build: config.status
${MAKE}
clean: clean-patched unpatch
clean-patched:
$(testdir)
$(testroot)
${MAKE} distclean
rm -rf debian/imaginary-package debian/files debian/substvars
patch: patch-stamp
patch-stamp:
dpatch apply-all
dpatch cat-all >patch-stamp
unpatch:
dpatch deapply-all
rm -rf patch-stamp debian/patched
Adding dpatch scriptlets to a package
When using dpatch, one surely wants to tell the system what dpatches to
apply, and which ones to discard. In the most common situation, one
only needs to list the names of the dpatches (the filenames relative to
debian/patches) in debian/patches/00list. They usually have the
extension .dpatch and the extension can be omitted, thus a file
debian/patches/01_one_patch.dpatch is written as 01_one_patch inside
debian/patches/00list
However, there may be situations where something more flexible is
needed, like applying the same patch on only two architectures, say,
m68k and powerpc. One solve this in at least two very different ways:
One is to list the same patch in both debian/patches/00list.m68k and
debian/patches/00list.powerpc, the other is to use DPATCH_OPTION_CPP=1
in debian/patches/00options. 00list file is passed through cpp command
with DEB_BUILD_ARCH variable set to the architecture, and
DEB_BUILD_ARCH_architecture being set to 1. With cpp, our sample
debian/patches/00list might look like this:
01_manpage_typo
#if defined(DEB_BUILD_ARCH_m68k) || defined(DEB_BUILD_ARCH_powerpc)
/* This patch fixes a random build-time breakage on Macintosh boxen. */
02_macintosh_foo
#endif
Creating dpatch scriptlets
There are many ways to create dpatch scriptlets. They are simple,
executable files, which follow a standardised calling convention
(documented in dpatch(7)).
You can fire up your $EDITOR, or use dpatch-edit-patch, and you should
be all set.
For most cases, where the dpatch file is only to apply a simple patch,
there is an even easier way:
dpatch patch-template -p "01_some_patch" "A random patch" \
<random.diff >debian/patches/01_some_patch.dpatch
FILES
debian/patches/00list
The list of patches to apply, deapply, or otherwise fiddle with.
debian/patches/00list.arch
List of patches to work with - additionally to the common list
in debian/patches/00list -, when building on the arch
architecture.
/etc/dpatch.conf
System-wide configuration file for dpatch, for setting global
options permanently.
~/.dpatch.conf
Per-user configuration file, for setting global options
permanently.
AUTHORS
dpatch was written by Joerg Jaspert, David B Harris, Gergely Nagy,
Junichi Uekawa and others.
This manual page was written by Gergely Nagy, and updated by Junichi
Uekawa
SEE ALSO
dpatch(7), dpatch.make(7), dpatch-edit-patch(1), dpatch-list-patch(1),
dpatch-get-origtargz(1), dpatch-convert-diffgz(1)