Yocto Bitbake Recipe How To Override do_install() and do_install_append()

Question

I am trying to add the open source "procps" package to my working Yocto build. This package installs a bunch of binaries that replace those provided by BusyBox. I only want one of these binaries - pgrep.

In my layer I created a bbappend file named "procps_%bbappend". It is picked up by the build, compiles successfully, but then fails on the install. The error messages seem to indicate that the do_install() and do_install_append() hooks are not overridden completely.

How can I change my bitbake bbappend file to only install the pgrep utility and none of the other standard installs from the "procps" package?

Here is my bbappend file that fails:

do_install () {
    install -d ${D}${base_bindir}
    mv ${D}/../build/pgrep ${D}/bin/pgrep
}

do_install_append () {
    install -d ${D}${base_bindir}
    mv ${D}/../build/pgrep ${D}/bin/pgrep
}

bindir_progs = ""
base_bindir_progs = ""
base_sbindir_progs = ""

Here is the entire "procps" bitbake recipe:

SUMMARY = "System and process monitoring utilities"
DESCRIPTION = "Procps contains a set of system utilities that provide system information about processes using \
the /proc filesystem. The package includes the programs ps, top, vmstat, w, kill, and skill."
HOMEPAGE = "https://gitorious.org/procps"
SECTION = "base"
LICENSE = "GPLv2+ & LGPLv2+"
LIC_FILES_CHKSUM="file://COPYING;md5=b234ee4d69f5fce4486a80fdaf4a4263 \
                  file://COPYING.LIB;md5=4cf66a4984120007c9881cc871cf49db \
                 "

DEPENDS = "ncurses"

inherit autotools gettext pkgconfig update-alternatives

SRC_URI = "http://downloads.sourceforge.net/project/procps-ng/Production/procps-ng-${PV}.tar.xz \
           file://sysctl.conf \
          "

SRC_URI[md5sum] = "6cc5b94c1c5b8cbc89ad345a7b522f74"
SRC_URI[sha256sum] = "e9493169a2d2adc0bc045538707310c8e877b385e4e296143b62607d2bb044ed"

S = "${WORKDIR}/procps-ng-${PV}"

EXTRA_OECONF = "--enable-skill --disable-modern-top"

CPPFLAGS += "-I${S}"

do_install_append () {
    install -d ${D}${base_bindir}
    [ "${bindir}" != "${base_bindir}" ] && for i in ${base_bindir_progs}; do mv ${D}${bindir}/$i ${D}${base_bindir}/$i; done
    install -d ${D}${base_sbindir}
    [ "${sbindir}" != "${base_sbindir}" ] && for i in ${base_sbindir_progs}; do mv ${D}${sbindir}/$i ${D}${base_sbindir}/$i; done
        if [ "${base_sbindir}" != "${sbindir}" ]; then
                rmdir ${D}${sbindir}
        fi

        install -d ${D}${sysconfdir}
        install -m 0644 ${WORKDIR}/sysctl.conf ${D}${sysconfdir}/sysctl.conf
        if ${@bb.utils.contains('DISTRO_FEATURES','systemd','true','false',d)}; then
                install -d ${D}${sysconfdir}/sysctl.d
                ln -sf ../sysctl.conf ${D}${sysconfdir}/sysctl.d/99-sysctl.conf
        fi
}

CONFFILES_${PN} = "${sysconfdir}/sysctl.conf"

bindir_progs = "free pkill pmap pgrep pwdx skill snice top uptime"
base_bindir_progs += "kill pidof ps watch"
base_sbindir_progs += "sysctl"

ALTERNATIVE_PRIORITY = "200"

ALTERNATIVE_${PN} = "${bindir_progs} ${base_bindir_progs} ${base_sbindir_progs}"

ALTERNATIVE_${PN}-doc = "kill.1 uptime.1"
ALTERNATIVE_LINK_NAME[kill.1] = "${mandir}/man1/kill.1"
ALTERNATIVE_LINK_NAME[uptime.1] = "${mandir}/man1/uptime.1"

python __anonymous() {
    for prog in d.getVar('base_bindir_progs', True).split():
        d.setVarFlag('ALTERNATIVE_LINK_NAME', prog, '%s/%s' % (d.getVar('base_bindir', True), prog))

    for prog in d.getVar('base_sbindir_progs', True).split():
        d.setVarFlag('ALTERNATIVE_LINK_NAME', prog, '%s/%s' % (d.getVar('base_sbindir', True), prog))
}

Solution

do_install () {
    install -d ${D}${base_bindir}
    mv ${D}/../build/pgrep ${D}/bin/pgrep
}

do_install_append () {
    install -d ${D}${base_bindir}
    mv ${D}/../build/pgrep ${D}/bin/pgrep
}

There's a few bits of confusion here:

• You can't "override" another _append: the one in the original recipe will still be appended
• Even if you could, your version would try to mv the same file twice (in the install and the append): that would fail. mv in general is a bad idea here: use install that's what it's for.
• Using ${D}/../build/ is not right, you probably want ${B} instead -- but that should also be the default directory for do_install() so you shouldn't need it at all.

You could let the original do_install() do what it wants, and then remove the bits you don't want in do_install_append()... but I think modifying the package so much is not a great idea: what if another package runtime depends on procps and expects the tools you removed?

Some alternatives for you:

• copy the recipe under a new name and just modify it
• Let do_install be as is and in your bbappend add a new package PACKAGES =+ ${PN}-pgrep and set FILES_${PN}-pgrep = "${bindir}/pgrep": then you could install only the new tiny procps-pgrep package instead of procps. This might need some tweaking to get right because of the alternatives system procps uses...