depcheck

#!/bin/bash
# PODNAME: depcheck
#
# Copyright (c) 2014 Michael Palimaka <kensington@gentoo.org>
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
# THE SOFTWARE.
#
# A tool to report both undeclared and potentially-unused runtime dependencies.
#
# Depends on app-misc/pax-utils, app-portage/portage-utils and
# sys-apps/gentoo-functions.

DEBUG=FALSE
IGNORE_DEPS=( "sys-libs/glibc" "sys-devel/gcc" )
IGNORE_LINKS=( "/lib64/libgcc_s.so.1" )
PKG_DIR="/var/db/pkg/"

. /lib/gentoo/functions.sh

bold() {
    echo $@
    return
    local bold=$(tput bold)
    local normal=$(tput sgr0)
    echo "${bold}${@}${normal}"
}

debug() {
    if [ $DEBUG = TRUE ]; then
        # write to stderr so as not to interfere with function returns
        echo "$@" 1>&2
    fi
}

# app-foo/bar-1.2.3-r1 -> app-foo/bar
remove_atom_version() {
    local atom=`qatom "${1}" | cut -d " " -f 1-2 | tr " " /`
    echo $atom
}

virtualcheck() {
    debug Checking if ${libowner_pn} is provided by a virtual
    for virtual in $(qdepends --nocolor --name-only --${1} --query ${libowner_pn} | grep ^virtual/)
    do
        debug Checking if ${virtual} is in dependencies
        local isvirtualdep=$(qdepends --${1} ${atom} | grep ${virtual})

        if [ $? -eq 0 ]; then
            used_virtuals+=( ${virtual} )
            continue 2
        fi
    done

    if [ "${1}" = "depend" ]; then
        eerror "${obj} links to ${link}"
    fi
    eindent
    eerror Missing ${1^^} on $(bold ${libowner_pn})
    eoutdent
    errors=1
}

check_atom() {

    local errors=0
    local atom=$1
    local checked=()
    local rdepends=()
    local used_virtuals=()

    local objects=`qlist -qo ${atom}`

    if [ ! "${objects}" ]; then
        einfo ${atom} does not have any objects installed, skipping...
        echo
        return
    fi

    if [ -z "${INSIDE_PORTAGE}" ]; then
        einfo Checking ${atom} for undeclared dependencies
        eindent
    fi

    local obj
    for obj in $objects
    do
        debug "Checking ${obj}"

        readelf -h ${obj} > /dev/null 2>&1

        # can it have stuff linked to it?
        if [ $? -ne 0 ]; then
            debug "It can't have links, skipping"
            continue
        fi

        local elf=`scanelf --format "#f%n" --nobanner --use-ldpath ${obj} 2>&1`
        local links=`echo ${elf} | tr "," " "`

        # get a list of everything that it's linked to
        local link
        for link in $links
        do
            local ignore
            for ignore in "${IGNORE_LINKS[@]}"; do
                if [ "${ignore}" = "${link}" ]; then
                    debug "Ignoring ${link} due to blacklist"
                    continue 2
                fi
            done

            # only check a library once per atom for performance reasons
            local check
            for check in "${checked[@]}"; do
                if [ "${check}" = "${link}" ]; then
                    debug "Already checked ${link} for this atom, skipping"
                    continue 2
                fi
            done

            checked=( "${checked[@]}" "${link}" )

            debug "Found ${link}"

            local libowner=`qfile -vqC ${link} | uniq`

            if [ ! "${libowner}" ]; then
                ewarn "Warning: installed file ${obj} is linked to ${link} which is not owned by any installed atom."
                continue
            fi

            debug "Owning package for ${link} is ${libowner}"

            local libowner_pn=$(remove_atom_version ${libowner})
            local my_pn=$(remove_atom_version ${atom})

            rdepends+=( "${libowner_pn}" )

            if [ "${libowner_pn}" = "${my_pn}" ]; then
                debug "Owning package is self, ignoring"
                continue
            fi

            local ignorelib
            for ignorelib in "${IGNORE_DEPS[@]}"
            do
                if [ "${libowner_pn}" = "${ignorelib}" ]; then
                    debug "Ignoring objects belonging to ${ignorelib}"
                    continue 2
                fi
            done

            debug "Checking if ${libowner_pn} is in the [R]DEPEND list of ${atom}"

            local isdep
            isdep=`qdepends -d ${atom} | grep ${libowner_pn}`
            if [ $? -ne 0 ]; then
                virtualcheck depend
            fi

            local isrdep
            isrdep=`qdepends -r ${atom} | grep ${libowner_pn}`
            if [ $? -ne 0 ]; then
                virtualcheck rdepend
            fi


        done

    done

    local ebuild_rdepends=()
    for rdepend in $(qdepends --nocolor --quiet --rdepend ${atom} | sed -e "s/\[[^]]*\]//g" | cut -d : -f 2-)
    do
        if [[ ${rdepend} = !* ]] ; then
            debug Skipping blocker: ${rdepend}
            continue
        elif [[ ${rdepend} = virtual/* ]] ; then
            for virtual in "${used_virtuals[@]}"
            do
                if [[ ${virtual} == $(remove_atom_version ${rdepend}) ]]; then
                    debug Skipping virtual: ${rdepend}
                    continue 2
                fi
            done
        fi
        ebuild_rdepends+=( $(remove_atom_version $rdepend) )
    done

    debug "Ebuild RDEPENDS: ${ebuild_rdepends[@]}"
    debug "Linked RDEPENDS: ${rdepends[@]}"

    local suspect_rdepends=$(comm -13 <(echo ${rdepends[@]} | sed 's/ /\n/g' | sort -u) <(echo ${ebuild_rdepends[@]} | sed 's/ /\n/g' | sort -u))
    if [ "${suspect_rdepends}" ]; then
        ewarn "Suspect RDEPEND: $(bold ${suspect_rdepends})"
    fi

    if [ -z "${INSIDE_PORTAGE}" ]; then
        eoutdent
        if [ -n "${CAT}" ]; then
            echo
        fi
    fi

    return $errors

}

check_package() {

    local package=$1
    local atoms=`qlist -IcCS ${package} | tr ' ' '-' | cut -d : -f1`

    debug Package ${package} own atoms: ${atoms}

    if [ ! "${atoms}" ]; then
        eerror ERROR: ${package} is not a valid atom
        exit 1
    fi

    for atom in ${atoms}; do
        check_atom ${atom}
    done

}

check_category() {

    local errors=0

    for package in `ls "${PKG_DIR}/${1}"`; do

        check_package "${1}/${package}"

        if [ $? -ne 0 ]; then
            errors=1
        fi

    done;

    return $errors

}

BINNAME=`basename ${0}`
if [ -z $1 ]; then
    echo "Checks emerged package(s) for undeclared depedencies"
    echo
        echo "Usage: ${BINNAME} [ atom | -c category | -a ]"
    echo
        echo "Examples:"
    echo "Check a single package: ${BINNAME} app-foo/bar-1.2.3"
    echo "Check a category: ${BINNAME} -c app-foo"
    echo "Check everything: ${BINNAME} -a"
    exit 1
fi

# check a particular category
if [ "$1" = "-c" ]; then

    CAT=$2

    if [ ! -d "${PKG_DIR}/${CAT}" ]; then
        eerror ERROR: No packages from the category ${CAT} have been emerged yet
        exit 1
    fi

    check_category $CAT

# check everything
elif [ "$1" = "-a" ]; then

    for category in `ls ${PKG_DIR}`; do
        check_category $category
    done;

else
    check_package $1
fi

if [ $DEBUG = TRUE ]; then
    if [ $? -eq 0 ]; then
        einfo Checking complete, no errors found
    else
        eerror Checking complete, errors found
    fi
fi