From 5ae4e671267e94d9bc9a16633ece5d24d9876c94 Mon Sep 17 00:00:00 2001 From: Joey Hess Date: Tue, 6 Apr 2010 21:42:08 -0400 Subject: [PATCH] dh: Improve documentation. joeyh: debhelper has an undocumented variable with INTERNAL in its name. People keep trying to use it. Why? liw: debhelper is magic. magic is power derived from secrets. secrets are desireable. solution: document it. :) --- debian/changelog | 1 + dh | 71 +++++++++++++++++++++++++++++++++++++----------- 2 files changed, 56 insertions(+), 16 deletions(-) diff --git a/debian/changelog b/debian/changelog index 6250450..e4108fe 100644 --- a/debian/changelog +++ b/debian/changelog @@ -17,6 +17,7 @@ debhelper (7.4.16) UNRELEASED; urgency=low * dh_md5sums: Sort to ensure stable, more diffable order. Closes: #573702 * dh: Allow --list-addons to be used when not in a source package. Closes: #574351 + * dh: Improve documentation. -- Joey Hess Thu, 18 Feb 2010 17:53:27 -0500 diff --git a/dh b/dh index 4f2b987..c4fec03 100755 --- a/dh +++ b/dh @@ -24,16 +24,6 @@ they only work on binary independent packages, and commands in the binary-arch sequences are passed the "-a" option to ensure they only work on architecture dependent packages. -Each debhelper command will record when it's successfully run in -debian/package.debhelper.log. (Which dh_clean deletes.) So dh can tell -which commands have already been run, for which packages, and skip running -those commands again. - -Each time dh is run, it examines the log, and finds the last logged command -that is in the specified sequence. It then continues with the next command -in the sequence. The B<--until>, B<--before>, B<--after>, and B<--remaining> -options can override this behavior. - If debian/rules contains a target with a name like "override_I", then when it would normally run I, dh will instead call that target. The override target can then run the command with additional options, @@ -145,9 +135,9 @@ easy way to do with is by adding an override target for that command. override_dh_installdocs: dh_installdocs README TODO -Sometimes the automated dh_auto_configure and dh_auto_build can't guess -what to do for a strange package. Here's how to avoid running either -and instead run your own commands. +Sometimes the automated L and L +can't guess what to do for a strange package. Here's how to avoid running +either and instead run your own commands. #!/usr/bin/make -f %: @@ -214,9 +204,8 @@ as follows. Then I will work. %: dh $@ --parallel -Finally, here is a way to prevent dh from running several commands -that you don't want it to run, by defining empty override targets for each -command. +Here is a way to prevent dh from running several commands that you don't +want it to run, by defining empty override targets for each command. #!/usr/bin/make -f %: @@ -225,6 +214,56 @@ command. # Commands not to run: override_dh_auto_test override_dh_compress override_dh_fixperms: +Sometimes, you may need to make an override target only run commands when a +particular package is being built. This can be accomplished using +L to test what is being built. For example: + + #!/usr/bin/make -f + %: + dh $@ + + override_dh_fixperms: + dh_fixperms + ifneq (,$(findstring foo, $(shell dh_listpackages))) + chmod 4755 debian/foo/usr/bin/foo + endif + +Finally, remember that you are not limited to using override targets in the +rules file when using dh. You can also explicitly define any of the regular +rules file targets when it makes sense to do so. A common reason to do this +is if your package needs different build-arch and build-indep targets. For +example, a package with a long document build process can put it in +build-indep to avoid build daemons redundantly building the documentation. + + #!/usr/bin/make -f + %: + dh $@ + + build: build-arch build-indep + build-indep: + $(MAKE) docs + build-arch: + $(MAKE) bins + +=head1 INTERNALS + +If you're curious about dh's internals, here's how it works under the hood. + +Each debhelper command will record when it's successfully run in +debian/package.debhelper.log. (Which dh_clean deletes.) So dh can tell +which commands have already been run, for which packages, and skip running +those commands again. + +Each time dh is run, it examines the log, and finds the last logged command +that is in the specified sequence. It then continues with the next command +in the sequence. The B<--until>, B<--before>, B<--after>, and B<--remaining> +options can override this behavior. + +dh uses the DH_INTERNAL_OPTIONS environment variable to pass information +through to debhelper commands that are run inside override targets. The +contents (and indeed, existence) of this environment variable, as the name +might suggest, is subject to change at any time. + =cut # Stash this away before init modifies it. -- 2.39.2