[PATCH v3 3/4] buildchroot: Add prepare and cleanup tasks

[Alexander Smirnov <asmirnov@ilbers.de>]

Some packages could require builchroot filesystem tunning, for
example share Isar downloads folder with chroot filesystem.

This patch adds two tasks for buildchroot:

1. 'do_prepare': This task is executed after buildchroot rootfs
generation and before 'do_build' from packages to be built.
Some notes:
 - An individual task is required for the case when you want to rebuild
   some package, this would require to run this preparation stuff for
   existing buildchroot rootfs.
 - This task should not have stamp. This means that anytime you want to
   build something, 'do_prepare' should be executed.

2. 'do_cleanup': This task is executed after all the packages are deployed.
Some notes:
 - This task also should not have stamp.
 - This task depends from the recipes listed in IMAGE_INSTALL.

Signed-off-by: Alexander Smirnov <asmirnov@ilbers.de>
---
 meta/classes/dpkg-base.bbclass                   |  3 ++-
 meta/classes/image.bbclass                       |  1 +
 meta/recipes-devtools/buildchroot/buildchroot.bb | 21 +++++++++++++++++++++
 3 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/meta/classes/dpkg-base.bbclass b/meta/classes/dpkg-base.bbclass
index 4941f9b..5d7f8b6 100644
--- a/meta/classes/dpkg-base.bbclass
+++ b/meta/classes/dpkg-base.bbclass
@@ -2,7 +2,7 @@
 # Copyright (C) 2017 Siemens AG
 
 # Add dependency from buildchroot creation
-do_build[depends] = "buildchroot:do_build"
+do_build[depends] = "buildchroot:do_prepare"
 
 # Each package should have its own unique build folder, so use
 # recipe name as identifier
@@ -24,6 +24,7 @@ do_build() {
         ret=$?
         sudo umount ${BUILDROOT} 2>/dev/null || true
         sudo rmdir ${BUILDROOT} 2>/dev/null || true
+        (exit $ret) || sudo umount ${BUILDCHROOT_DIR}/git
         (exit $ret) || bb_exit_handler
     }
     trap '_do_build_cleanup' EXIT
diff --git a/meta/classes/image.bbclass b/meta/classes/image.bbclass
index 7813b16..b0f645c 100644
--- a/meta/classes/image.bbclass
+++ b/meta/classes/image.bbclass
@@ -83,6 +83,7 @@ do_populate() {
 
 addtask populate before do_build after do_unpack
 do_populate[deptask] = "do_deploy_deb"
+do_populate[depends] = "buildchroot:do_cleanup"
 
 do_rootfs[stamp-extra-info] = "${MACHINE}-${DISTRO}"
 
diff --git a/meta/recipes-devtools/buildchroot/buildchroot.bb b/meta/recipes-devtools/buildchroot/buildchroot.bb
index 6a94733..fe88e98 100644
--- a/meta/recipes-devtools/buildchroot/buildchroot.bb
+++ b/meta/recipes-devtools/buildchroot/buildchroot.bb
@@ -67,7 +67,28 @@ do_build() {
     # Install package builder script
     sudo install -m 755 ${WORKDIR}/build.sh ${BUILDCHROOT_DIR}
 
+    # Create share point for downloads
+    sudo install -d ${BUILDCHROOT_DIR}/git
+
     # Configure root filesystem
     sudo chroot ${BUILDCHROOT_DIR} /configscript.sh
     _do_build_cleanup
 }
+
+do_prepare[nostamp] = "1"
+
+do_prepare() {
+    sudo mount --bind ${GITDIR} ${BUILDCHROOT_DIR}/git
+}
+
+addtask prepare after do_build
+
+DEPENDS += "${IMAGE_INSTALL}"
+do_cleanup[deptask] = "do_deploy_deb"
+do_cleanup[nostamp] = "1"
+
+do_cleanup() {
+    sudo umount ${BUILDCHROOT_DIR}/git
+}
+
+addtask cleanup after do_prepare
-- 
2.9.5