Create more than one debian package

I am trying to create debian packages, from CPP sources that are built using CMake.

I am using debuild, I am NOT using cpack.

Till now I have reached the following stage:

debian/rules looks like the following:

%:
    dh $@ --buildsystem=cmake

override_dh_auto_configure:
    dh_auto_configure -- --no-warn-unused-cli -DPACKAGE_ONE=ON -DPACKAGE_TWO=OFF

debian/control looks like:

Source: blabla
Maintainer: ME <[email protected]>
Section: misc
Priority: optional
Build-Depends:
 debhelper-compat (= 12),
 cmake (>= 3.10.0),

Package: package1
Architecture: any
Pre-Depends: ${misc:Pre-Depends}
Depends:
 ${misc:Depends},
 ${shlibs:Depends},
 ${debconf:Depends},
 unzip
Description: Package 1
 The first package.

#Package: package2
#Architecture: any
#Pre-Depends: ${misc:Pre-Depends}
#Depends:
# ${misc:Depends},
# ${shlibs:Depends},
# ${debconf:Depends},
# unzip
#Description: Package 2
# The second package.

A very simplified CMakeLists.txt looks like:

project(blabla)

add_subdirectory(common_dependencies)

if(PACKAGE_ONE)
  add_subdirectory(package1)
endif()

if(PACKAGE_TWO)
  add_subdirectory(package2)
endif()

add_subdirectory(other_dependencies)

CMakeLists.txt in the respective package1/2 sub-directories takes care of creating the executable, etc...

The problem is that for the result I need to generate two different debian packages (package1.deb, package2.deb) when calling debuild...

But I simply cannot guess how can I build two different debian packages from the same source, using the above requirements, ie: pass in a CMake flag, when there is only one debian/rules file (installing various extra files for the different packages I have sorted out by creating package1.install, package2.install with all the files, images, icons, etc ... they need)

Is this even possible? Thanks!

Solution

it's of course possible (and rather common) to build multiple binary packages from a single source package.

the debian/control must list every binary packages that is being created.
there's only a single debian/rules file, because this file contains the recipe to build everything
typically you would then sort the various build artifacts into either of your two binary packages

so typically you would have a debian/control like this (note that package2 has been un-commented):

Source: blabla
Maintainer: ME <[email protected]>
Section: misc
Priority: optional
Build-Depends:
 debhelper-compat (= 12),
 cmake (>= 3.10.0),

Package: package1
Architecture: any
Pre-Depends: ${misc:Pre-Depends}
Depends:
 ${misc:Depends},
 ${shlibs:Depends},
 ${debconf:Depends},
 unzip
Description: Package 1
 The first package.

Package: package2
Architecture: any
Pre-Depends: ${misc:Pre-Depends}
Depends:
 ${misc:Depends},
 ${shlibs:Depends},
 ${debconf:Depends},
 unzip
Description: Package 2
 The second package.

your debian/rules might look like this (note that both packages are built):

%:
    dh $@ --buildsystem=cmake

override_dh_auto_configure:
    dh_auto_configure -- --no-warn-unused-cli -DPACKAGE_ONE=ON -DPACKAGE_TWO=ON

the only thing that is left is sorting the build artifacts into the two packages.

assume that building with -DPACKAGE_ONE=1 produces an an artifact /usr/bin/package1 and -DPACKAGE_ONE=2 produces an an artifact /usr/bin/package2 when running make install.

then you need to create/edit some more files, debian/package1.install and debian/package2.install that - being very declarative - simply list the files that go into each package.

so debian/package1.install would contain:

/usr/bin/package1

and debian/package2.install would contain:

/usr/bin/package2

under the hood, dh invokes dh_auto_install which instructs cmake to install all files into DESTDIR=$(pwd)/debian/tmp/. this is the place where dh_install will look for files listed in the various debian/*.install files and sort them into $(pwd)/debian/<pkgname>/, before assembling the final package. there are many ways to tweak all this, but the standard behavior will most likely fit your needs.