path: root/lib/cpt-pkg

# Package functions
# shellcheck source=lib-cpt

run_hook() {
    # Store the CPT_HOOK variable so that we can revert it if it is changed.
    oldCPT_HOOK=$CPT_HOOK

    # If a fourth parameter 'root' is specified, source the hook from a
    # predefined location to avoid privilige escalation through user scripts.
    [ "$4" ] && CPT_HOOK=$CPT_ROOT/etc/cpt-hook

    [ -f "$CPT_HOOK" ] || { CPT_HOOK=$oldCPT_HOOK; return 0 ;}

    [ "$2" ] && log "$2" "Running $1 hook"

    TYPE=${1:-null} PKG=${2:-null} DEST=${3:-null} . "$CPT_HOOK"
    CPT_HOOK=$oldCPT_HOOK
}

pkg_lint() {
    # Check that each mandatory file in the package entry exists.
    log "$1" "Checking repository files"

    repo_dir=$(pkg_find "$1")

    cd "$repo_dir" || die "'$repo_dir' not accessible"
    [ -f sources ] || warn "$1" "Sources file not found"
    [ -x build ]   || die "$1" "Build file not found or not executable"
    [ -s version ] || die "$1" "Version file not found or empty"

    read -r _ release 2>/dev/null < version || die "Version file not found"
    [ "$release" ] || die "Release field not found in version file"

    [ "$2" ] || [ -f checksums ] || die "$pkg" "Checksums are missing"
}

pkg_cache() {
    read -r version release 2>/dev/null < "$(pkg_find "$1")/version"

    # Initially assume that the package tarball is built with the CPT_COMPRESS
    # value.
    if [ -f "$bin_dir/$1#$version-$release.tar.$CPT_COMPRESS" ]; then
        tar_file="$bin_dir/$1#$version-$release.tar.$CPT_COMPRESS"
    else
        set +f; set -f -- "$bin_dir/$1#$version-$release.tar."*
        tar_file=$1
    fi

    [ -f "$tar_file" ]
}

pkg_strip() {
    # Strip package binaries and libraries. This saves space on the
    # system as well as on the tarballs we ship for installation.

    # Package has stripping disabled, stop here.
    [ -f "$mak_dir/$pkg/nostrip" ] && return

    log "$1" "Stripping binaries and libraries"

    find "$pkg_dir/$1" -type f | while read -r file; do
        case $(od -A o -t c -N 18 "$file") in
            # REL (object files (.o), static libraries (.a)).
            *177*E*L*F*0000020\ 001\ *|*\!*\<*a*r*c*h*\>*)
                strip -g -R .comment -R .note "$file"
            ;;

            # EXEC (static binaries).
            # DYN (shared libraries, dynamic binaries).
            # Shared libraries keep global symbols in a separate ELF section
            # called '.dynsym'. '--strip-all/-s' does not touch the dynamic
            # symbol entries which makes this safe to do.
            *177*E*L*F*0000020\ 00[23]\ *)
                strip -s -R .comment -R .note "$file"
            ;;
        esac
    done 2>/dev/null ||:
}

pkg_manifest() (
    # Generate the package's manifest file. This is a list of each file
    # and directory inside the package. The file is used when uninstalling
    # packages, checking for package conflicts and for general debugging.
    log "$1" "Generating manifest"

    # This function runs as a sub-shell to avoid having to 'cd' back to the
    # prior directory before being able to continue.
    cd "${2:-$pkg_dir}/$1"

    # find: Print all files and directories and append '/' to directories.
    # sort: Sort the output in *reverse*. Directories appear *after* their
    #       contents.
    # sed:  Remove the first character in each line (./dir -> /dir) and
    #       remove all lines which only contain '.'.
    find . -type d -exec printf '%s/\n' {} + -o -print |
        sort -r | sed '/^\.\/$/d;ss.ss' > "${2:-$pkg_dir}/$1/$pkg_db/$1/manifest"
)

pkg_etcsums() (
    # This function runs as a sub-shell to avoid having to 'cd' back to the
    # prior directory before being able to continue.
    cd "$pkg_dir/$1/etc" 2>/dev/null || return 0; cd ..

    # Generate checksums for each configuration file in the package's
    # /etc/ directory for use in "smart" handling of these files.
    log "$1" "Generating etcsums"


    find etc -type f | while read -r file; do
        sh256 "$file"
    done > "$pkg_dir/$1/$pkg_db/$1/etcsums"
)

pkg_tar() {
    # Create a tarball from the built package's files.
    # This tarball also contains the package's database entry.
    log "$1" "Creating tarball"

    # Read the version information to name the package.
    read -r version release < "$(pkg_find "$1")/version"

    # Create a tarball from the contents of the built package.
    "$tar" cf - -C "$pkg_dir/$1" . |
        case $CPT_COMPRESS in
            bz2) bzip2 -z ;;
            xz)  xz -zT 0 ;;
            gz)  gzip -6  ;;
            zst) zstd -3  ;;
            *)   gzip -6  ;;  # Fallback to gzip
        esac \
    > "$bin_dir/$1#$version-$release.tar.$CPT_COMPRESS"

    log "$1" "Successfully created tarball"

    run_hook post-package "$1" "$bin_dir/$1#$version-$release.tar.$CPT_COMPRESS"
}

pkg_build() {
    # Build packages and turn them into packaged tarballs. This function
    # also checks checksums, downloads sources and ensure all dependencies
    # are installed.
    pkg_build=1

    log "Resolving dependencies"

    for pkg do contains "$explicit" "$pkg" || {
        pkg_depends "$pkg" explicit

        # Mark packages passed on the command-line
        # separately from those detected as dependencies.
        explicit="$explicit $pkg "
    } done

    [ "$pkg_update" ] || explicit_build=$explicit

    # If an explicit package is a dependency of another explicit
    # package, remove it from the explicit list as it needs to be
    # installed as a dependency.
    # shellcheck disable=2086,2031
    for pkg do
        contains "$deps" "$pkg" && explicit=$(pop "$pkg" from $explicit)
    done

    # See [1] at top of script.
    # shellcheck disable=2046,2086,2031
    set -- $deps $explicit

    log "Building: $*"

    # Only ask for confirmation if more than one package needs to be built.
    [ $# -gt 1 ] || [ "$pkg_update" ] && { prompt || exit 0 ;}

    log "Checking for pre-built dependencies"

    for pkg do pkg_lint "$pkg"; done

    # Install any pre-built dependencies if they exist in the binary
    # directory and are up to date.
    for pkg do ! contains "$explicit_build" "$pkg" && pkg_cache "$pkg" && {
        log "$pkg" "Found pre-built binary, installing"
        (CPT_FORCE=1 cpt-install "$tar_file")

        # Remove the now installed package from the build list.
        # See [1] at top of script.
        # shellcheck disable=2046,2086
        set -- $(pop "$pkg" from "$@")
    } done

    for pkg do pkg_sources "$pkg"; done

    pkg_verify "$@"

    # Finally build and create tarballs for all passed packages and
    # dependencies.
    for pkg do
        log "$pkg" "Building package ($((in = in + 1))/$#)"

        pkg_extract "$pkg"
        repo_dir=$(pkg_find "$pkg")

        read -r build_version _ < "$repo_dir/version"

        # Copy the build file to the build directory to users to modify it
        # temporarily at runtime.
        cp -f "$repo_dir/build" "$mak_dir/$pkg/.build.cpt"

        # Install built packages to a directory under the package name
        # to avoid collisions with other packages.
        mkdir -p "$pkg_dir/$pkg/$pkg_db"

        # Move to the build directory.
        cd "$mak_dir/$pkg"

        log "$pkg" "Starting build"

        run_hook pre-build "$pkg" "$pkg_dir/$pkg"

        # Notify the user if the build script is changed during the pre-build
        # hook.
        diff -q "$repo_dir/build" .build.cpt ||
            log "$pkg" "Executing the modified build file"

        # Call the build script, log the output to the terminal
        # and to a file. There's no PIPEFAIL in POSIX shelll so
        # we must resort to tricks like killing the script ourselves.
        { ./.build.cpt "$pkg_dir/$pkg" "$build_version" "$sys_arch" 2>&1 || {
            log "$pkg" "Build failed"
            log "$pkg" "Log stored to $log_dir/$pkg-$time-$pid"
            run_hook build-fail "$pkg" "$pkg_dir/$pkg"
            pkg_clean
            kill 0
        } } | tee "$log_dir/$pkg-$time-$pid"

        # Run the test script if it exists and the user wants to run tests. This
        # is turned off by default.
        [ -x "$repo_dir/test" ] && [ "$CPT_TEST" = 1 ] && {
            run_hook pre-test "$pkg" "$pkg_dir/$pkg"
            log "$pkg" "Running tests"
            "$repo_dir/test" "$pkg_dir/$pkg" "$build_version" "$sys_arch" 2>&1 || {
                log "$pkg" "Test failed"
                log "$pkg" "Log stored to $log_dir/$pkg-$time-$pid"
                run_hook test-fail "$pkg" "$pkg_dir/$pkg"
                pkg_clean
                kill 0
        } } | tee -a "$log_dir/$pkg-$time-$pid"

        # Delete the log file if the build succeeded to prevent
        # the directory from filling very quickly with useless logs.
        [ "$CPT_KEEPLOG" = 1 ] || rm -f "$log_dir/$pkg-$time-$pid"

        # Copy the repository files to the package directory.
        # This acts as the database entry.
        cp -LRf "$repo_dir" "$pkg_dir/$pkg/$pkg_db/"

        # Copy the modified build file to the package directory.
        pkg_build="$pkg_dir/$pkg/$pkg_db/$pkg/build"
        diff -U 3 "$pkg_build" .build.cpt > "$pkg_build.diff" &&
            rm -f "$pkg_build.diff"

        # We don't want the package manager to track 'dir' pages of the info
        # directory. We don't want every single package to create their own dir
        # files either.
        rm -f "$pkg_dir/$pkg/usr/share/info/dir"

        # We never ever want this. Let's end the endless conflicts
        # and remove it.
        find "$pkg_dir/$pkg" -name charset.alias -exec rm -f {} +

        # Remove libtool's '*.la' library files. This removes cross-build
        # system conflicts that may arise. Build-systems change, libtool
        # is getting deprecated, we don't want a package that depends on
        # some package's '.la' files.
        find "$pkg_dir/$pkg" -name '*.la' -exec rm -f {} +

        log "$pkg" "Successfully built package"

        run_hook post-build "$pkg" "$pkg_dir/$pkg"

        # Create the manifest file early and make it empty.
        # This ensures that the manifest is added to the manifest.
        : > "$pkg_dir/$pkg/$pkg_db/$pkg/manifest"

        # If the package contains '/etc', add a file called
        # 'etcsums' to the manifest. See comment directly above.
        [ -d "$pkg_dir/$pkg/etc" ] &&
            : > "$pkg_dir/$pkg/$pkg_db/$pkg/etcsums"

        pkg_strip    "$pkg"
        pkg_manifest "$pkg"
        pkg_fix_deps "$pkg"
        pkg_manifest "$pkg"
        pkg_etcsums  "$pkg"
        pkg_tar      "$pkg"

        # Install only dependencies of passed packages.
        # Skip this check if this is a package update.
        contains "$explicit" "$pkg" && [ -z "$pkg_update" ] && continue

        log "$pkg" "Needed as a dependency or has an update, installing"

        (CPT_FORCE=1 cpt-install "$pkg")
    done

    # End here as this was a system update and all packages have been installed.
    [ "$pkg_update" ] && return

    log "Successfully built package(s)"

    # Turn the explicit packages into a 'list'.
    # See [1] at top of script.
    # shellcheck disable=2046,2086
    set -- $explicit

    # Only ask for confirmation if more than one package needs to be installed.
    [ $# -gt 1 ] && prompt "Install built packages? [$*]" && {
        cpt-install "$@"
        return
    }

    log "Run 'cpt i $*' to install the package(s)"
}

pkg_checksums() {
    # Generate checksums for packages.
    repo_dir=$(pkg_find "$1")

    [ -f "$repo_dir/sources" ] || return 0

    while read -r src _ || [ "$src" ]; do
        # Comment.
        if [ -z "${src##\#*}" ]; then
            continue

        # File is local to the package.
        elif [ -f "$repo_dir/$src" ]; then
            src_path=$repo_dir/${src%/*}

        # File is remote and was downloaded.
        elif [ -f "$src_dir/$1/${src##*/}" ]; then
            src_path=$src_dir/$1

        # File is a git repository.
        elif [ -z "${src##git+*}" ]; then continue

        # Die here if source for some reason, doesn't exist.
        else
            die "$1" "Couldn't find source '$src'"
        fi

        # An easy way to get 'sha256sum' to print with the 'basename'
        # of files is to 'cd' to the file's directory beforehand.
        (cd "$src_path" && sh256 "${src##*/}") ||
            die "$1" "Failed to generate checksums"
    done < "$repo_dir/sources"
}

pkg_verify() {
    # Verify all package checksums. This is achieved by generating a new set of
    # checksums and then comparing those with the old set.
    verify_cmd="NR==FNR{a[\$1];next}/^git  .*/{next}!((\$1)in a){exit 1}"

    for pkg; do
        repo_dir=$(pkg_find "$pkg")
        [ -f "$repo_dir/sources" ] || continue

        pkg_checksums "$pkg" | awk "$verify_cmd" - "$repo_dir/checksums" || {
        log "$pkg" "Checksum mismatch"

        # Instead of dying above, log it to the terminal. Also define a
        # variable so we *can* die after all checksum files have been
        # checked.
        mismatch="$mismatch$pkg "
    } done

    [ -z "$mismatch" ] || die "Checksum mismatch with: ${mismatch% }"
}

pkg_conflicts() {
    # Check to see if a package conflicts with another.
    log "$1" "Checking for package conflicts"

    # Filter the tarball's manifest and select only files
    # and any files they resolve to on the filesystem
    # (/bin/ls -> /usr/bin/ls).
    while read -r file; do
        case $file in */) continue; esac

        # Use $CPT_ROOT in filename so that we follow its symlinks.
        file=$CPT_ROOT/${file#/}

        # We will only follow the symlinks of the directories, so we reserve the
        # directory name in this 'dirname' value. If we cannot find it in the
        # system, we don't need to make this much more complex by trying so hard
        # to find it. Simply use the original directory name.
        dirname="$(_readlinkf "${file%/*}" 2>/dev/null)" ||
            dirname="${file%/*}"


        # Combine the dirname and file values, and print them into the
        # temporary manifest to be parsed.
        printf '%s/%s\n' "${dirname#$CPT_ROOT}" "${file##*/}"

    done < "$tar_dir/$1/$pkg_db/$1/manifest" > "$CPT_TMPDIR/$pid/manifest"

    p_name=$1

    # Generate a list of all installed package manifests
    # and remove the current package from the list.
    # shellcheck disable=2046,2086
    set -- $(set +f; pop "$sys_db/$p_name/manifest" from "$sys_db"/*/manifest)

    [ -s "$CPT_TMPDIR/$pid/manifest" ] || return 0

    # In rare cases where the system only has one package installed
    # and you are reinstalling that package, grep will try to read from
    # standard input if we continue here.
    #
    # Also, if we don't have any packages installed grep will give an
    # error. This will not cause the installation to fail, but we don't
    # need to check for conflicts if that's the case anyway. If we have
    # only zero packages or one package, just stop wasting time and continue
    # with the installation.
    [ "$1" ] && [ -f "$1" ] || return 0

    # Store the list of found conflicts in a file as we will be using the
    # information multiple times. Storing it in the cache dir allows us
    # to be lazy as they'll be automatically removed on script end.
    "$grep" -Fxf "$CPT_TMPDIR/$pid/manifest" -- "$@" > "$CPT_TMPDIR/$pid/conflict" ||:


    # Enable alternatives automatically if it is safe to do so.
    # This checks to see that the package that is about to be installed
    # doesn't overwrite anything it shouldn't in '/var/db/cpt/installed'.
    "$grep" -q ":/var/db/cpt/installed/" "$CPT_TMPDIR/$pid/conflict" ||
        choice_auto=1

    # Use 'grep' to list matching lines between the to
    # be installed package's manifest and the above filtered
    # list.
    if [ "$CPT_CHOICE" != 0 ] && [ "$choice_auto" = 1 ]; then

        # This is a novel way of offering an "alternatives" system.
        # It is entirely dynamic and all "choices" are created and
        # destroyed on the fly.
        #
        # When a conflict is found between two packages, the file
        # is moved to a directory called "choices" and its name
        # changed to store its parent package and its intended
        # location.
        #
        # The package's manifest is then updated to reflect this
        # new location.
        #
        # The 'cpt choices' command parses this directory and
        # offers you the CHOICE of *swapping* entries in this
        # directory for those on the filesystem.
        #
        # The choices command does the same thing we do here,
        # it rewrites manifests and moves files around to make
        # this work.
        #
        # Pretty nifty huh?
        while IFS=: read -r _ con; do
            printf '%s\n' "Found conflict $con"

            # Create the "choices" directory inside of the tarball.
            # This directory will store the conflicting file.
            mkdir -p "$tar_dir/$p_name/${cho_dir:=var/db/cpt/choices}"

            # Construct the file name of the "db" entry of the
            # conflicting file. (pkg_name>usr>bin>ls)
            con_name=$(printf %s "$con" | sed 's|/|>|g')

            # Move the conflicting file to the choices directory
            # and name it according to the format above.
            mv -f "$tar_dir/$p_name/$con" \
                  "$tar_dir/$p_name/$cho_dir/$p_name$con_name" 2>/dev/null || {
                log "File must be in ${con%/*} and not a symlink to it"
                log "This usually occurs when a binary is installed to"
                log "/sbin instead of /usr/bin (example)"
                log "Before this package can be used as an alternative,"
                log "this must be fixed in $p_name. Contact the maintainer"
                die "by checking 'git log' or by running 'cpt-maintainer'"
            }
        done < "$CPT_TMPDIR/$pid/conflict"

        # Rewrite the package's manifest to update its location
        # to its new spot (and name) in the choices directory.
        pkg_manifest "$p_name" "$tar_dir" 2>/dev/null

    elif [ -s "$CPT_TMPDIR/$pid/conflict" ]; then
        log "Package '$p_name' conflicts with another package" "" "!>"
        log "Run 'CPT_CHOICE=1 cpt i $p_name' to add conflicts" "" "!>"
        die "as alternatives."
    fi
}

pkg_swap() {
    # Swap between package alternatives.
    pkg_list "$1" >/dev/null

    alt=$(printf %s "$1$2" | sed 's|/|>|g')
    cd "$sys_db/../choices"

    [ -f "$alt" ] || [ -h "$alt" ] ||
        die "Alternative '$1 $2' doesn't exist"

    if [ -f "$2" ]; then
        # Figure out which package owns the file we are going to swap for
        # another package's.
        #
        # Print the full path to the manifest file which contains
        # the match to our search.

        pkg_owns=$(pkg_owner -lFx "$2") ||
            die "File '$2' exists on filesystem but isn't owned"

        log "Swapping '$2' from '$pkg_owns' to '$1'"

        # Convert the current owner to an alternative and rewrite
        # its manifest file to reflect this. We then resort this file
        # so no issues arise when removing packages.
        cp  -Pf "$CPT_ROOT/$2" "$pkg_owns>${alt#*>}"
        sed "s#^$(regesc "$2")\$#${PWD#$CPT_ROOT}/$pkg_owns>${alt#*>}#" \
            "../installed/$pkg_owns/manifest" |
            sort -r -o "../installed/$pkg_owns/manifest"
    fi

    # Convert the desired alternative to a real file and rewrite
    # the manifest file to reflect this. The reverse of above.
    mv -f "$alt" "$CPT_ROOT/$2"
    sed "s#^${PWD#$CPT_ROOT}/$(regesc "$alt")\$#$2#" "../installed/$1/manifest" |
        sort -r -o "../installed/$1/manifest"
}

pkg_etc() {
    [ -d "$tar_dir/$pkg_name/etc" ] || return 0

    (cd "$tar_dir/$pkg_name"

    # Create all directories beforehand.
    find etc -type d | while read -r dir; do
        mkdir -p "$CPT_ROOT/$dir"
    done

    # Handle files in /etc/ based on a 3-way checksum check.
    find etc ! -type d | while read -r file; do
        { sum_new=$(sh256 "$file")
          sum_sys=$(cd "$CPT_ROOT/"; sh256 "$file")
          sum_old=$("$grep" "$file$" "$mak_dir/c"); } 2>/dev/null ||:

        log "$pkg_name" "Doing 3-way handshake for $file"
        printf '%s\n' "Previous: ${sum_old:-null}"
        printf '%s\n' "System:   ${sum_sys:-null}"
        printf '%s\n' "New:      ${sum_new:-null}"

        # Use a case statement to easily compare three strings at
        # the same time. Pretty nifty.
        case ${sum_old:-null}${sum_sys:-null}${sum_new} in
            # old = Y, sys = X, new = Y
            "${sum_new}${sum_sys}${sum_old}")
                log "Skipping $file"
                continue
            ;;

            # old = X, sys = X, new = X
            # old = X, sys = Y, new = Y
            # old = X, sys = X, new = Y
            "${sum_old}${sum_old}${sum_old}"|\
            "${sum_old:-null}${sum_sys}${sum_sys}"|\
            "${sum_sys}${sum_old}"*)
                log "Installing $file"
                new=
            ;;

            # All other cases.
            *)
                warn "$pkg_name" "saving /$file as /$file.new" "->"
                new=.new
            ;;
        esac

        cp -fPp "$file"  "$CPT_ROOT/${file}${new}"
        chown root:root "$CPT_ROOT/${file}${new}" 2>/dev/null
    done) ||:
}

pkg_remove() {
    # Remove a package and all of its files. The '/etc' directory
    # is handled differently and configuration files are *not*
    # overwritten.
    pkg_list "$1" >/dev/null || return

    # Make sure that nothing depends on this package.
    [ "$CPT_FORCE" = 1 ] || {
        log "$1" "Checking for reverse dependencies"

        (cd "$sys_db"; set +f; grep -lFx "$1" -- */depends) &&
            die "$1" "Can't remove package, others depend on it"
    }
    # Block being able to abort the script with 'Ctrl+C' during removal.
    # Removes all risk of the user aborting a package removal leaving
    # an incomplete package installed.
    trap_set block

    if [ -x "$sys_db/$1/pre-remove" ]; then
        log "$1" "Running pre-remove script"
        "$sys_db/$1/pre-remove" ||:
    fi

    # Create a temporary list of all directories, so we don't accidentally
    # remove anything from packages that create empty directories for a
    # purpose (such as baselayout).
    manifest_list="$(set +f; pop "$sys_db/$1/manifest" from "$sys_db/"*/manifest)"
    # shellcheck disable=2086
    [ "$manifest_list" ] && grep -h '/$' $manifest_list | sort -ur > "$mak_dir/dirs"

    run_hook pre-remove "$1" "$sys_db/$1" root

    while read -r file; do
        # The file is in '/etc' skip it. This prevents the package
        # manager from removing user edited configuration files.
        [ "${file##/etc/*}" ] || continue

        if [ -d "$CPT_ROOT/$file" ]; then
            "$grep" -Fxq "$file" "$mak_dir/dirs" 2>/dev/null && continue
            rmdir "$CPT_ROOT/$file" 2>/dev/null || continue
        else
            rm -f "$CPT_ROOT/$file"
        fi
    done < "$sys_db/$1/manifest"

    # Reset 'trap' to its original value. Removal is done so
    # we no longer need to block 'Ctrl+C'.
    trap_set cleanup

    run_hook post-remove "$1" "$CPT_ROOT/" root

    log "$1" "Removed successfully"
}

pkg_install() {
    # Install a built package tarball.

    # Install can also take the full path to a tarball.
    # We don't need to check the repository if this is the case.
    if [ -f "$1" ] && [ -z "${1%%*.tar*}" ] ; then
        tar_file=$1
        pkg_name=${1##*/}
        pkg_name=${pkg_name%#*}

    else
        pkg_cache "$1" ||
            die "package has not been built, run 'cpt b pkg'"

        pkg_name=$1
    fi

    mkdir -p "$tar_dir/$pkg_name"
    log "$pkg_name" "Extracting $tar_file"

    # Extract the tarball to catch any errors before installation begins.
    decompress "$tar_file" | "$tar" xf - -C "$tar_dir/$pkg_name"

    [ -f "$tar_dir/$pkg_name/$pkg_db/$pkg_name/manifest" ] ||
        die "'${tar_file##*/}' is not a valid CPT package"

    # Ensure that the tarball's manifest is correct by checking that
    # each file and directory inside of it actually exists.
    [ "$CPT_FORCE" != 1 ] && log "$pkg_name" "Checking package manifest" &&
        while read -r line; do
            # Skip symbolic links
            [ -h "$tar_dir/$pkg_name/$line" ] ||
            [ -e "$tar_dir/$pkg_name/$line" ] || {
        log "File $line missing from tarball but mentioned in manifest" "" "!>"
        TARBALL_FAIL=1
        }
    done < "$tar_dir/$pkg_name/$pkg_db/$pkg_name/manifest"
    [ "$TARBALL_FAIL" ] && {
        log "You can still install this package by setting CPT_FORCE variable"
        die "$pkg_name" "Missing files in manifest"
    }

    log "$pkg_name" "Checking that all dependencies are installed"

    # Make sure that all run-time dependencies are installed prior to
    # installing the package.
    [ -f "$tar_dir/$pkg_name/$pkg_db/$pkg_name/depends" ] &&
    [ "$CPT_FORCE" != 1 ] &&
        while read -r dep dep_type || [ "$dep" ]; do
            [ "${dep##\#*}" ] || continue
            [ "$dep_type" ]   || pkg_list "$dep" >/dev/null ||
                install_dep="$install_dep'$dep', "
        done < "$tar_dir/$pkg_name/$pkg_db/$pkg_name/depends"

    [ "$install_dep" ] && die "$1" "Package requires ${install_dep%, }"

    run_hook pre-install "$pkg_name" "$tar_dir/$pkg_name" root

    pkg_conflicts "$pkg_name"

    log "$pkg_name" "Installing package incrementally"

    # Block being able to abort the script with Ctrl+C during installation.
    # Removes all risk of the user aborting a package installation leaving
    # an incomplete package installed.
    trap_set block

    # If the package is already installed (and this is an upgrade) make a
    # backup of the manifest and etcsums files.
    cp -f "$sys_db/$pkg_name/manifest" "$mak_dir/m" 2>/dev/null ||:
    cp -f "$sys_db/$pkg_name/etcsums"  "$mak_dir/c" 2>/dev/null ||:

    # This is repeated multiple times. Better to make it a function.
    pkg_rsync() {
        rsync "--chown=$USER:$USER" --chmod=Du-s,Dg-s,Do-s \
              -WhHKa --no-compress --exclude /etc "${1:---}" \
              "$tar_dir/$pkg_name/" "$CPT_ROOT/"
    }

    # Install the package by using 'rsync' and overwrite any existing files
    # (excluding '/etc/').
    pkg_rsync --info=progress2
    pkg_etc

    # Remove any leftover files if this is an upgrade.
    "$grep" -vFxf "$sys_db/$pkg_name/manifest" "$mak_dir/m" 2>/dev/null |

    while read -r file; do
        file=$CPT_ROOT/$file

        # Skip deleting some leftover files.
        case $file in /etc/*) continue; esac

        # Remove files.
        if [ -f "$file" ] && [ ! -L "$file" ]; then
            rm -f "$file"

        # Remove file symlinks.
        elif [ -h "$file" ] && [ ! -d "$file" ]; then
            unlink "$file" ||:

        # Skip directory symlinks.
        elif [ -h "$file" ] && [ -d "$file" ]; then :

        # Remove directories if empty.
        elif [ -d "$file" ]; then
            rmdir "$file" 2>/dev/null ||:
        fi
    done ||:

    log "$pkg_name" "Verifying installation"
    { pkg_rsync; pkg_rsync; } ||:

    # Reset 'trap' to its original value. Installation is done so
    # we no longer need to block 'Ctrl+C'.
    trap_set cleanup

    if [ -x "$sys_db/$pkg_name/post-install" ]; then
        log "$pkg_name" "Running post-install script"
        "$sys_db/$pkg_name/post-install" ||:
    fi

    run_hook post-install "$pkg_name" "$sys_db/$pkg_name" root

    log "$pkg_name" "Installed successfully"
}

pkg_updates(){
    # Check all installed packages for updates. So long as the installed
    # version and the version in the repositories differ, it's considered
    # an update.
    [ "$CPT_FETCH" = 0 ] || pkg_fetch

    log "Checking for new package versions"

    set +f

    for pkg in "$sys_db/"*; do
        pkg_name=${pkg##*/}

        # Read version and release information from the installed packages
        # and repository.
        read -r db_ver db_rel < "$pkg/version"
        read -r re_ver re_rel < "$(pkg_find "$pkg_name")/version"

        # Compare installed packages to repository packages.
        [ "$db_ver-$db_rel" != "$re_ver-$re_rel" ] && {
            printf '%s\n' "$pkg_name $db_ver-$db_rel ==> $re_ver-$re_rel"
            outdated="$outdated$pkg_name "
        }
    done

    set -f

    # If the download option is specified only download the outdated packages
    # and exit.
    # shellcheck disable=2154
    [ "$download_only" = 1 ] && {
        log "Only sources for the packages will be acquired"
        prompt || exit 0

        for pkg in $outdated; do
            pkg_sources "$pkg"
        done

        exit 0
    }

    contains "$outdated" cpt && {
        log "Detected package manager update"
        log "The package manager will be updated first"

        prompt || exit 0

        pkg_build cpt
        cpt-install cpt

        log "Updated the package manager"
        log "Re-run 'cpt update' to update your system"

        exit 0
    }

    [ "$outdated" ] || {
        log "Everything is up to date"
        return
    }

    log "Packages to update: ${outdated% }"

    # Tell 'pkg_build' to always prompt before build.
    pkg_update=1

    # Build all packages requiring an update.
    # See [1] at top of script.
    # shellcheck disable=2046,2086
    {
        pkg_order $outdated
        pkg_build $order
    }

    log "Updated all packages"
}

pkg_clean() {
    # Clean up on exit or error. This removes everything related
    # to the build.
    [ "$CPT_DEBUG" != 1 ] || return 0

    # Block 'Ctrl+C' while cache is being cleaned.
    trap_set block

    # Remove temporary items.
    rm -rf -- "${CPT_TMPDIR:=$cac_dir/proc}/$pid"
}

create_cache() {
    # A temporary directory can be specified apart from the cache
    # directory in order to build in a user specified directory.
    # /tmp could be used in order to build on ram, useful on SSDs.
    # The user can specify CPT_TMPDIR for this.
    #
    # Create the required temporary directories and set the variables
    # which point to them.
    mkdir -p "${tmp_dir:=${CPT_TMPDIR:=$cac_dir/proc}/$pid}"

    # If an argument is given, skip the creation of other cache directories.
    # This here makes shellcheck extremely angry, so I am globally disabling
    # SC2119.
    [ "$1" ] || mkdir -p "${mak_dir:=$tmp_dir/build}" \
                         "${pkg_dir:=$tmp_dir/pkg}" \
                         "${tar_dir:=$tmp_dir/export}"

}

# Local Variables:
# mode: sh
# End: