29 Using an External SCM

If you’re working on a recipe that pulls from an external Source Code Manager (SCM), it is possible to have the OpenEmbedded build system notice new recipe changes added to the SCM and then build the resulting packages that depend on the new recipes by using the latest versions. This only works for SCMs from which it is possible to get a sensible revision number for changes. Currently, you can do this with Apache Subversion (SVN), Git, and Bazaar (BZR) repositories.

To enable this behavior, the PV of the recipe needs to include a + sign in its assignment. Here is an example:

PV = "1.2.3+git"

Bitbake later includes the source control information in PKGV during the packaging phase.

Then, you can add the following to your local.conf:

SRCREV:pn-PN = "${AUTOREV}"

PN is the name of the recipe for which you want to enable automatic source revision updating.

If you do not want to update your local configuration file, you can add the following directly to the recipe to finish enabling the feature:

SRCREV = "${AUTOREV}"

The Yocto Project provides a distribution named poky-bleeding, whose configuration file contains the line:

require conf/distro/include/poky-floating-revisions.inc

This line pulls in the listed include file that contains numerous lines of exactly that form:

#SRCREV:pn-opkg-native ?= "${AUTOREV}"
#SRCREV:pn-opkg-sdk ?= "${AUTOREV}"
#SRCREV:pn-opkg ?= "${AUTOREV}"
#SRCREV:pn-opkg-utils-native ?= "${AUTOREV}"
#SRCREV:pn-opkg-utils ?= "${AUTOREV}"
SRCREV:pn-gconf-dbus ?= "${AUTOREV}"
SRCREV:pn-matchbox-common ?= "${AUTOREV}"
SRCREV:pn-matchbox-config-gtk ?= "${AUTOREV}"
SRCREV:pn-matchbox-desktop ?= "${AUTOREV}"
SRCREV:pn-matchbox-keyboard ?= "${AUTOREV}"
SRCREV:pn-matchbox-panel-2 ?= "${AUTOREV}"
SRCREV:pn-matchbox-themes-extra ?= "${AUTOREV}"
SRCREV:pn-matchbox-terminal ?= "${AUTOREV}"
SRCREV:pn-matchbox-wm ?= "${AUTOREV}"
SRCREV:pn-settings-daemon ?= "${AUTOREV}"
SRCREV:pn-screenshot ?= "${AUTOREV}"
. . .

These lines allow you to experiment with building a distribution that tracks the latest development source for numerous packages.

Note

The poky-bleeding distribution is not tested on a regular basis. Keep this in mind if you use it.