.\" -*- nroff -*-
.\" This manual is for dpatch, a patch maintenance system for Debian
.\" 
.\" Copyright (C) 2003, 2004, 2005 Gergely Nagy <algernon@bonehunter.rulez.org>
.\"
.\" Permission is granted to make and distribute verbatim copies of this
.\" manual provided the copyright notice and this permission notice are
.\" preserved on all copies.
.\"
.\" Permission is granted to copy and distribute modified versions of this
.\" manual under the conditions for verbatim copying, provided that the
.\" entire resulting derived work is distributed under the terms of a
.\" permission notice identical to this one.
.\"
.\" Permission is granted to copy and distribute translations of this
.\" manual into another language, under the above conditions for modified
.\" versions, except that this permission notice may be stated in a
.\" translation approved by the Author.
.TH DPATCH 1 "Dec 13 2011" "DPATCH 2" "dpatch"
.SH "NAME"
dpatch \- patch maintenance system for Debian

.SH "SYNOPSIS"
.BI "dpatch [" options ] " command " [ command\-arguments ]

.SH "DESCRIPTION"
\fBdpatch\fR 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
\fIdebian/patches\fR 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
\fBpatch/unpatch\fR target in the \fBbuild\fR or \fBclean\fR stage of
\fIdebian/rules\fR. For added flexibility, you can call
\fI/usr/bin/dpatch\fR directly too.

.SH WARNING
.B dpatch
is deprecated, please switch to the `3.0 (quilt)' Debian source
package format instead. See
.I http://wiki.debian.org/Projects/DebSrc3.0#FAQ
for a short guide on how to do it.

.SH "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:
.TP
.BI "\-\-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
\fB\-\-chdir\fR option explained below.
.TP
.B \-\-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 \fB\-\-workdir\fR option.
.TP
.B \-\-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).
.TP
.B \-\-force (\-F)
Force the application or deapplication of patches, even if dpatch
would normally skip them because the operation was already done
earlier.

.TP
.B \-\-with\-cpp
Force the use of cpp. Overrides use of 
.B "DPATCH_OPTION_CPP=1" 
option in
.I "debian/patches/00options"
file.

.SH "COMMANDS"
.SS "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
\fB\-all\fR 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 \fB\-until\fR or \fB\-up\-to\fR
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.

.P
.BI "apply [" options ]
.br
.BI "patch [" options ]
.RS
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.

.B Options
.RS
.BI \-\-stampdir= directory ", \-s=" directory
.RS
Put stamp files into \fIdirectory\fR instead of the default
\fIdebian/patched\fR.
.RE
.B \-\-help (\-h)
.RS
Print a short help message about the command.
.RE
.B \-\-quiet (\-q)
.RS
Forces the command to not print anything.
.RE
.B \-\-verbose (\-v)
.RS
Disables hiding of the scriptlet output.
.RE
.RE
.RE

.P
.BI "deapply [" options ]
.br
.BI "unpatch [" options ]
.RS
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).

.B Options
.RS
.BI \-\-stampdir= directory ", \-s=" directory
.RS
Use stamp files in \fIdirectory\fR instead of the default
\fIdebian/patched\fR.
.RE
.B \-\-help (\-h)
.RS
Print a short help message about the command.
.RE
.B \-\-quiet (\-q)
.RS
Forces the command to not print anything.
.RE
.B \-\-verbose (\-v)
.RS
Disables hiding of the scriptlet output.
.RE
.RE
.RE

.TP
.BI "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).

.RS
.B Options
.RS
.B \-\-no\-meta, \-\-desc-only (\-nm, \-d)
.RS
Only print the patch description.
.RE
.B \-\-author\-only (\-a)
.RS
Only print the author of the patch.
.RE
.B \-\-no\-desc, (\-nd)
.RS
Do not print the patch description.
.RE
.B \-\-help (\-h)
.RS
Print a short help message about the command.
.RE
.B \-\-quiet (\-q)
.RS
Forces the command to not print anything.
.RE
.RE
.RE

.TP
.BI "list [" options ]
List the name of the given patches. This commands is not really
useful, except the \fBlist\-all\fR variant, which lists all available
patches.

.RS
.B Options
.RS
.B \-\-help (\-h)
.RS
Print a short help message about the command.
.RE
.RE
.RE

.TP
.BI "status [" options ]
Prints the status of the given patches - whether they are applied to
the working tree or not.

.RS
.B Options
.RS
.BI \-\-stampdir= directory ", \-s=" directory
.RS
Use stamp files in \fIdirectory\fR instead of the default
\fIdebian/patched\fR.
.RE
.B \-\-help (\-h)
.RS
Print a short help message about the command.
.RE
.B \-\-quiet (\-q)
.RS
Forces the command to not print anything.
.RE
.RE
.RE

.TP
.BI "log [" options ]
Displays the log of the given patching attempts.

.RS
.B Options
.RS
.BI \-\-stampdir= directory ", \-s=" directory
.RS
Use stamp files in \fIdirectory\fR instead of the default
\fIdebian/patched\fR.
.RE
.B \-\-help (\-h)
.RS
Print a short help message about the command.
.RE
.B \-\-quiet (\-q)
.RS
Forces the command to not print anything, but the logs without extra
sugar on top.
.RE
.RE
.RE

.TP
.BI "call [" options ]
Call a dpatch with a user\-specified argument. All arguments with a
\fBpkg\-\fR 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.

.RS
.B Options
.RS
.BI \-\-argument= "arg " (\-a= arg)
.RS
Call patches with \fIarg\fR as argument.
.RE
.B \-\-help (\-h)
.RS
Print a short help message about the command.
.RE
.B \-\-quiet (\-q)
.RS
Forces the command to not print anything.
.RE
.RE
.RE

.SS "Miscellaneous commands"
.TP
.BI "patch\-template [" options "] [" patchname "] [" description ]
Print a quasi\-standard dpatch script template, based on the
information give on the command\-line. If a \fIdescription\fR 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.

.RS
.B Options
.RS
.B \-\-prepend (\-p)
.RS
Prepend the template to STDIN.
.RE
.B \-\-help (\-h)
.RS
Print a short help message about the command.
.RE
.RE
.RE

.TP
.BI "help (\-\-help, \-h) [" command ]
Attempt to give a little more detailed help about dpatch itself, or
about a given dpatch command.
.TP
.B version
Prints the dpatch version number and exits.

.SH "DPATCH IN DEBIAN PACKAGES"
There are two different ways to use dpatch in \fIdebian/rules\fR:
calling it directly, or including \fBdpatch.make\fR(7). Only the
former method will be described here \- the latter has its own manual
page.

\fINOTE\fR: The following examples also require adding the
\fB.NOTPARALLEL\fR flag to the head of \fIdebian/rules\fR since the
dependency lists rely on the order of the
execution. Without \fB.NOTPARALLEL\fR, they execution order may be wrong
with multiple make threads (the \fI-j\fR 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 \fIdebian/rules\fR. However, in common
practice most packages have a \fBbuild\fR (or \fBbuild\-stamp\fR),
\fBconfig.status\fR, or \fBconfigure\fR (or \fBconfigure\-stamp\fR)
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 \fBclean\fR rule touches files modified by dpatches (creating
incompatible changes), you can safely add \fBunpatch\fR to the list of
the \fBclean\fR 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 \fBclean\fR target to,
say, \fBclean\-patched\fR, write a rule that calls dpatch to deapply the
dpatches, and make a new \fBclean\fR rule that has \fBclean\-patched\fR and
\fBunpatch\fR as its prerequisites.

Let us look at an example! First, let us look at the relevant parts of
the original \fIdebian/rules\fR of our imaginary package:

.RS
.sp
.nf
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
.fi
.sp
.RE

After dpatchifying, this would look like this:

.RS
.sp
.nf
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
.fi
.sp
.RE

.SS "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 \fIdebian/patches\fR) in \fIdebian/patches/00list\fR.
They usually have the extension 
.B ".dpatch"
and the extension can be omitted, thus a file 
.B "debian/patches/01_one_patch.dpatch"
is written as 
.B "01_one_patch"
inside
.B "debian/patches/00list"

However, there may be situations where something more flexible is
needed, like applying the same patch on only two architectures, say,
\fBm68k\fR and \fBpowerpc\fR. One solve this in at least two very
different ways: One is to list the same patch in both
\fIdebian/patches/00list.m68k\fR and
\fIdebian/patches/00list.powerpc\fR, the other is to use
\fBDPATCH_OPTION_CPP=1\fR in \fIdebian/patches/00options\fR.
00list file is passed through
.B cpp
command with 
.B DEB_BUILD_ARCH
variable set to the architecture,
and 
.BI "DEB_BUILD_ARCH_" "architecture"
being set to 1.
With cpp, our sample \fIdebian/patches/00list\fR might look
like this:

.RS
.sp
.nf
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
.fi

.SS "Creating dpatch scriptlets"
There are many ways to create dpatch scriptlets. They are simple,
executable files, which follow a standardised calling convention
(documented in \fBdpatch\fR(7)).

You can fire up your $EDITOR, or use \fBdpatch\-edit\-patch\fR, 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:

.RS
.sp
.nf
dpatch patch\-template \-p "01_some_patch" "A random patch" \\
	<random.diff >debian/patches/01_some_patch.dpatch
.fi
.sp
.RE


.SH "FILES"
.TP
.I debian/patches/00list
.RS
The list of patches to apply, deapply, or otherwise fiddle with.
.RE
.TP
.I debian/patches/00list.\fBarch\fI
.RS
List of patches to work with - additionally to the common list in
\fIdebian/patches/00list\fR -, when building on the \fBarch\fR
architecture.
.RE
.TP
.I /etc/dpatch.conf
.RS
System-wide configuration file for dpatch, for setting global options
permanently.
.RE
.TP
.I ~/.dpatch.conf
.RS
Per-user configuration file, for setting global options permanently.
.RE

.SH "AUTHORS"
.B 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

.SH "SEE ALSO"
.BR "dpatch" "(7), "
.BR "dpatch.make" "(7), "
.BR "dpatch\-edit\-patch" "(1), "
.BR "dpatch\-list\-patch" "(1), "
.BR "dpatch\-convert\-diffgz" "(1)"

.\" arch-tag: a45571c1-b231-43cd-8fe5-00be30315328