#!@@CT_bash@@

# NON-CONFIGURABLE STUFF!

export LC_ALL=C

version="@@CT_VERSION@@"

bits="@@CT_BITS@@"

sed="@@CT_sed@@"

grep="@@CT_grep@@"

my_name="$( basename "${0}" )"

prefix="${0%-ldd}"

gcc="${prefix}-gcc"

readelf="${prefix}-readelf"

fake_load_addr_root="$((0xdeadbeef))"

fake_load_addr_rpath="$((0xdeadc0de))"

fake_load_addr_sysroot="$((0x8badf00d))"

ld_library_path="/lib:/usr/lib"

do_error() {

    printf "%s: %s\n" "${my_name}" "$*" >&2

}

do_opt_error() {

    do_error "$@"

    printf "Try \`%s --help' for more information\n" "${my_name}" >&2

}

do_trace() {

    local depth=0

    [ -z "${CT_XLDD_VERBOSE}" ] && return 0

    for((depth=0; "${#FUNCNAME[$((depth+1))]}" != 0; depth++)); do :; done

    printf "%*s" $((4*(depth-1))) "" >&2

    printf -- "$@" >&2

}

show_version() {

    # Fake a real ldd, just in case some dumb script would check

    cat <<_EOF_

ldd (crosstool-NG) ${version}

Copyright (C) 2010 "Yann E. MORIN" <yann.morin.1998@free.fr>

This is free software; see the source for copying conditions.  There is NO

warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

Licensed under the GPLv2, see the file LICENSES in the top-directory of the

sources for this package.

_EOF_

}

show_help() {

    cat <<_EOF_

Usage: ${my_name} [OPTION]... --root DIR FILE...

      --help              print this help and exit

      --version           print version information and exit

      --root dir          treat dir as being the root of the target

  -s, --show-system       mark libs from the sysroot with a trailing '[*]'

                          and libs found via RPATH with a trailing '[+]'

_EOF_

    cat <<_EOF_ |fmt

${my_name} tries to mimick the behavior of a real native ldd, but can be

used in a cross-development environment. Here is how it differs from a

real native ldd:

If the CT_XLDD_VERBOSE variable is set and non-empty, then ${my_name} will

print a lot of debug messages, explaining how it builds the library

search path, and how each library was found and why.

The LD_LIBRARY_PATH variable is not used, as it can not reliably be

guessed except at runtime, and we can't run.

${my_name} does not scan /etc/ld.so.cache, but instead uses /etc/ld.so.conf

(it understands the include directives therein for libces that have that).

${my_name} also interprets (tries to!) the RPATH/RUNPATH records found in

the dynamic ELF section. Such paths are searched for only relative to

the specified root, not from the sysroot (see below). Also, those paths

are searched for not only for the file they appear in, but also for its

dependencies.

${my_name} will search the directory specified with --root for libraries

to resolve the NEEDED tags. If --root is not set, then ${my_name} will

use the value in the environment variable \${CT_XLDD_ROOT}. If neither

is set, then this is an error.

If NEEDED libraries can't be found in the specified root directory, then

${my_name} will also look in the sysroot of the toolchain to see if it

can find them.

For NEEDED libraries that were found, the output will look like:

        libneeded.so => /path/to/libneeded.so (0xloadaddr)

and for those that were not found, the output will look like:

        libneeded.so not found

The paths are relative to the specified root directory, or to the sysroot

(eg. /lib/libneeded.so, /usr/lib/libneeded.so, and so on...).

The expected load address 'loadaddr' is a faked address to match the output

of the real ldd, but has no actual meaning (set to some constants for now,

0x8badf00d for libraries from the sysroot, 0xdeadc0de for those found via

the RPATH/RUNPATH records, and 0xdeadbeef for others).

_EOF_

# Unimplemeted yet:

#  -d, --data-relocs       process data relocations

#  -r, --function-relocs   process data and function relocations

#  -u, --unused            print unused direct dependencies

#  -v, --verbose           print all information

# See also this thread:

#  http://sourceware.org/ml/crossgcc/2008-09/msg00057.html

}

# Parse command line options

root="${CT_XLDD_ROOT}"

show_system=

while true; do

    case "${1}" in

        --help)

            show_help

            exit 0

            ;;

        --version)

            show_version

            exit 0

            ;;

        --root)

            root="$2"

            shift

            ;;

        --root=*)

            root="${1#--root=}"

            ;;

        --show-system|-s)

            show_system=1

            ;;

        -*)

            do_opt_error "unrecognized option \`${1}'"

            exit 1

            ;;

        *)

            break

            ;;

    esac

    shift

done

# Sanity checks

if [ -z "${root}" ]; then

    do_opt_error "no root given"

    exit 1

fi

if [ ! -d "${root}" ]; then

    do_error "\`${root}': no such file or directory"

    exit 1

fi

sysroot="$( "${gcc}" -print-sysroot 2>/dev/null )"

if [ -z "${sysroot}" ]; then

    sysroot="$( "${gcc}" -print-file-name=libc.so 2>/dev/null   \

                |sed -r -e 's:/usr/lib/libc.so$::;'             \

              )"

fi

if [ -z "${sysroot}" ]; then

    do_error "unable to find sysroot for \`${gcc}'"

fi

do_report_needed_found() {

    local needed="${1}"

    local path="${2}"

    local origin="${3}"

    local loadaddr

    local sys

    case "${origin}" in

        root)

            loadaddr="${fake_load_addr_root}"

            ;;

        rpath)

            loadaddr="${fake_load_addr_rpath}"

            if [ -n "${show_system}" ]; then

                sys=" [+]"

            fi

            ;;

        sysroot)

            loadaddr="${fake_load_addr_sysroot}"

            if [ -n "${show_system}" ]; then

                sys=" [*]"

            fi

            ;;

    esac

    printf "%8s%s => %s (0x%0*x)%s\n"   \

           ""                           \

           "${needed}"                  \

           "${path}"                    \

           "$((bits/4))"                \

           "${loadaddr}"                \

           "${sys}"

}

# Search a needed file, scanning ${lib_dir} in the root directory

do_find_needed() {

    local needed="${1}"

    local -a list

    local -a dirs

    local found

    local where

    local base

    local d i

    do_trace "Searching for '%s'\n" "${needed}"

    # rpath shall come first!

    list=(                      \

        "rpath:${root}"         \

        "root:${root}"          \

        "sysroot:${sysroot}"    \

    )

    for i in "${list[@]}"; do

        where="${i%%:*}"

        base="${i#*:}"

        if [ "${where}" = "rpath" ]; then

            dirs=( "${search_rpath[@]}" )

        else

            dirs=( "${needed_search_path[@]}" )

        fi

        for d in "${dirs[@]}"; do

            do_trace "-> looking in '%s' (%s)\n" "${d}" "${where}"

            if [ -f "${base}${d}/${needed}" ]; then

                found="${d}/${needed}"

                do_trace "---> found\n"

                break 2

            fi

        done

    done

    if [ -n "${found}" ]; then

        do_report_needed_found "${needed}" "${found}" "${where}"

        do_process_file "${base}${found}"

    else

        printf "%8s%s not found\n" "" "${needed}"

    fi

    do_trace "Done searching for '%s'\n" "${needed}"

}

# Scan a file for all NEEDED tags

do_process_file() {

    local file="${1}"

    local -a save_search_rpath

    local n m

    local found

    do_trace "Parsing file '%s'\n" "${file}"

    save_search_rpath=( "${search_rpath[@]}" )

    for n in $( "${readelf}" -d "${file}"                                           \

                |"${grep}" -E '\((RPATH|RUNPATH)\)'                                 \

                |"${sed}" -r -e 's/^.*Library r(|un)path:[[:space:]]+\[(.*)\]$/\2/;'\

              ); do

        do_trace "-> adding rpath '%s'\n" "${n}"

        search_rpath+=( "${n}" )

    done

    do_trace ": search path:\n"

    for n in "${search_rpath[@]}" "${needed_search_path[@]}"; do

        do_trace ": - '%s'\n" "${n}"

    done

    do_trace ": end search path"

    for n in $( "${readelf}" -d "${file}"                                               \

                |"${grep}" -E '\(NEEDED\)'                                              \

                |"${sed}" -r -e 's/^.*Shared library:[[:space:]]+\[([^]]+)\].*/\1/;'    \

              ); do

        found=0

        for m in "${needed_list[@]}"; do

            [ "${n}" = "${m}" ] && found=1 && break

        done

        if [ ${found} -ne 0 ]; then

            do_trace "-> skipping already known dependency '%s'\n" "${n}"

            continue

        fi

        do_trace "-> handling new dependency '%s'\n" "${n}"

        needed_list+=( "${n}" )

        do_find_needed "${n}"

        do_trace "-> done handling dependency '%s'\n" "${n}"

    done

    search_rpath=( "${save_search_rpath[@]}" )

    do_trace "Finished parsing file '%s'\n" "${file}"

}

# Recursively scan a /etc/ld.so.conf file

do_scan_etc_ldsoconf() {

    local ldsoconf="${1}"

    local g

    local f

    [ -f "${ldsoconf}" ] || return 0

    do_trace "Parsing ld.so.conf: '%s'\n" "${ldsoconf}"

    while read line; do

        case "${line}" in

            include\ *)

                g="${root}${line#include }"

                do_trace "-> handling include directive '%s'\n" "${g}"

                for f in ${g}; do

                    do_scan_etc_ldsoconf "${f}"

                done

                do_trace "-> finished handling include directive '%s'\n" "${g}"

                ;;

            \#*|"")

                ;;

            *)

                do_trace "-> adding search dir '%s'\n" "${line}"

                needed_search_path+=( "${line}" )

                ;;

        esac

    done <"${ldsoconf}"

    do_trace "Finished parsing ld.so.conf: '%s'\n" "${ldsoconf}"

}

# Build up the full list of search directories

declare -a needed_search_path

do_trace "Adding basic lib dirs\n"

ld_library_path="${ld_library_path}:"

while [ -n "${ld_library_path}" ]; do

    d="${ld_library_path%%:*}"

    if [ -n "${d}" ]; then

        do_trace "-> adding search dir '%s'\n" "${d}"

        needed_search_path+=( "${d}" )

    fi

    ld_library_path="${ld_library_path#*:}"

done

do_trace "Done adding basic lib dirs\n"

do_trace "Scanning '/etc/ld.so.conf'\n"

do_scan_etc_ldsoconf "${root}/etc/ld.so.conf"

do_trace "Done scanning '/etc/ld.so.conf'\n"

do_trace "Search path:\n"

for p in "${needed_search_path[@]}"; do

    do_trace "-> '%s'\n" "${p}"

done

declare -a needed_list

declare -a search_rpath

do_trace "Scanning file '%s'\n" "${1}"

do_process_file "${1}"

do_trace "Done scanning file '%s'\n" "${1}"