OBS: make nightly packages conflict with latest

Add conflicting dummy packages osmocom-nightly and osmocom-latest, and
make all packages from each repository depend on the right one.

As usually, the latest packages will only get changed when a new release
appears. So the dependency will get introduced after tagging a new
release. I have tested in an own OBS namespace, that everything works as
expected.

Related: OS#2640
Change-Id: I79c45e798c10a65443b9fb9ecb54393d1918608a

scripts/common-obs.sh

@@ -0,0 +1,79 @@
+#!/bin/sh
+# Various common code used in the OBS (opensuse build service) related osmo-ci shell scripts
+
+# Create the source for a dummy package, that conflicts with another dummy package in the current directory. Example
+# of the structure that will be generated:
+# osmocom-nightly
+# └── debian
+#     ├── changelog
+#     ├── compat
+#     ├── control
+#     ├── copyright
+#     ├── rules
+#     └── source
+#         └── format
+# $1: name of dummy package (e.g. "osmocom-nightly")
+# $2: name of conflicting package (e.g. "osmocom-latest")
+osmo_obs_prepare_conflict() {
+	local pkgname="$1"
+	local pkgname_conflict="$2"
+	local pkgver="0.0.0"
+	local oldpwd="$PWD"
+
+	mkdir -p "$pkgname/debian/source"
+	cd "$pkgname/debian"
+
+	# Fill control, changelog, rules
+	cat << EOF > control
+Source: ${pkgname}
+Section: unknown
+Priority: optional
+Maintainer: Oliver Smith <osmith@sysmocom.de>
+Build-Depends: debhelper (>= 9)
+Standards-Version: 3.9.8
+
+Package: ${pkgname}
+Depends: \${misc:Depends}
+Architecture: any
+Conflicts: ${pkgname_conflict}
+Description: Dummy package, which conflicts with ${pkgname_conflict}
+EOF
+	cat << EOF > changelog
+${pkgname} (${pkgver}) unstable; urgency=medium
+
+  * Dummy package, which conflicts with ${pkgname_conflict}.
+
+ -- Oliver Smith <osmith@sysmocom.de>  Thu, 13 Jun 2019 12:50:19 +0200
+EOF
+	cat << EOF > rules
+#!/usr/bin/make -f
+%:
+	dh \$@
+EOF
+
+	# Finish up debian dir
+	chmod +x rules
+	echo "9" > compat
+	echo "3.0 (native)" > source/format
+	touch copyright
+
+	# Put in git repository
+	cd ..
+	git init .
+	git add -A
+	git commit -m "auto-commit: $pkgname dummy package" || true
+	git tag -f "$pkgver"
+
+	cd "$oldpwd"
+}
+
+# Add dependency to all (sub)packages in debian/control and commit the change.
+# $1: path to debian/control file
+# $2: name of the package to depend on
+osmo_obs_add_debian_dependency() {
+	# Note: adding the comma at the end should be fine. If there is a Depends: line, it is most likely not empty. It
+	# should at least have ${misc:Depends} according to lintian.
+	sed "s/^Depends: /Depends: $2, /g" -i "$1"
+
+	git -C "$(dirname "$1")" commit -m "auto-commit: debian: depend on $2" .
+}

scripts/osmocom-latest-packages.sh

@@ -1,4 +1,5 @@
 #!/bin/sh
+. "$(dirname "$0")/common-obs.sh"
 
 # requirements
 # apt install git-buildpackage osc git
@@ -28,6 +29,9 @@ prepare() {
   fi
   [ -d "$DEBSRCDIR" ] && rm -rf "$DEBSRCDIR"
   mkdir "$DEBSRCDIR"
+
+  cd "$TOP"
+  osmo_obs_prepare_conflict "osmocom-latest" "osmocom-nightly"
 }
 
 get_last_tag() {
@@ -84,6 +88,11 @@ build() {
   VER=$(get_last_tag "$project")
   if [ -x ./git-version-gen ]; then
     ./git-version-gen . > .tarball-version 2>/dev/null
+  fi
+
+  osmo_obs_add_debian_dependency "./debian/control" "osmocom-latest"
+
+  if [ -x ./git-version-gen ]; then
     gbp buildpackage -S -uc -us -d --git-ignore-branch "--git-export-dir=$output" \
 		     "--git-debian-branch=$VER" --git-ignore-new $gitbpargs \
 		     --git-postexport='cp $GBP_GIT_DIR/../.tarball-version $GBP_TMP_DIR/'
@@ -152,6 +161,7 @@ build_osmocom() {
 
   checkout_copy_debian8_jessie "osmo-gsm-manuals"
 
+  build osmocom-latest
   build limesuite --git-upstream-tree="$(get_last_tag limesuite)"
   build osmo-gsm-manuals
   build osmo-gsm-manuals-debian8-jessie

scripts/osmocom-nightly-packages.sh

@@ -1,4 +1,5 @@
 #!/bin/bash
+. "$(dirname "$0")/common-obs.sh"
 
 # requirements
 # apt install devscripts git-buildpackage osc git
@@ -23,6 +24,9 @@ prepare() {
   mkdir -p "$REPO/osc/"
   cd "$REPO/osc"
   osc co "$PROJ"
+
+  cd "$REPO"
+  osmo_obs_prepare_conflict "osmocom-nightly" "osmocom-latest"
 }
 
 get_last_tag() {
@@ -98,6 +102,7 @@ build() {
 
   if [ "$changelog" = "commit" ] ; then
     VER=$(get_commit_version)
+    osmo_obs_add_debian_dependency "./debian/control" "osmocom-nightly"
     dch -b -v "$VER" -m "Snapshot build"
     git commit -m "$VER snapshot" debian/
   fi
@@ -205,6 +210,7 @@ build_osmocom() {
   checkout_copy_debian8_jessie "osmo-gsm-manuals"
   checkout_copy_debian8_jessie "osmo-trx"
 
+  build osmocom-nightly
   build limesuite no_commit --git-upstream-tree="$(get_last_tag limesuite)"
   build osmo-gsm-manuals
   build osmo-gsm-manuals-debian8-jessie