#!/bin/sh # $FreeBSD: stable/11/tools/build/check-links.sh 294357 2016-01-19 22:42:16Z bdrewery $ libkey() { libkey="lib_symbols_$1" patterns=[.+,/-] replacement=_ while :; do case " ${libkey} " in *${patterns}*) libkey="${libkey%%${patterns}*}${replacement}${libkey#*${patterns}}" ;; *) break ;; esac done return 0 } usage() { cat <<-EOF usage: $0 [-Uv] [-L LD_LIBRARY_PATH] file -L: Specify an alternative LD_LIBRARY_PATH for the library resolution. -U: Skip looking for unresolved symbols. -v: Show which library each symbol is resolved to. EOF exit 0 } ret=0 CHECK_UNRESOLVED=1 VERBOSE_RESOLVED=0 while getopts "L:Uv" flag; do case "${flag}" in L) LIB_PATH="${OPTARG}" ;; U) CHECK_UNRESOLVED=0 ;; v) VERBOSE_RESOLVED=1 ;; *) usage ;; esac done shift $((OPTIND-1)) if ! [ -f "$1" ]; then echo "No such file or directory: $1" >&2 exit 1 fi mime=$(file -L --mime-type $1) isbin=0 case $mime in *application/x-executable) isbin=1 ;; *application/x-sharedlib);; *) echo "Not an elf file" >&2 ; exit 1;; esac # Gather all symbols from the target unresolved_symbols=$(nm -u -D --format=posix "$1" | awk '$2 == "U" {print $1}' | tr '\n' ' ') [ ${isbin} -eq 1 ] && bss_symbols=$(nm -D --format=posix "$1" | awk '$2 == "B" && $4 != "" {print $1}' | tr '\n' ' ') if [ -n "${LIB_PATH}" ]; then for libc in /lib/libc.so.*; do LDD_ENV="LD_PRELOAD=${libc}" done LDD_ENV="${LDD_ENV} LD_LIBRARY_PATH=${LIB_PATH}" fi ldd_libs=$(env ${LDD_ENV} ldd $(realpath $1) | awk '{print $1 ":" $3}') # Check for useful libs list_libs= resolved_symbols= for lib in $(readelf -d $1 | awk '$2 ~ /\(?NEEDED\)?/ { sub(/\[/,"",$NF); sub(/\]/,"",$NF); print $NF }'); do echo -n "checking if $lib is needed: " if [ -n "${lib##/*}" ]; then for libpair in ${ldd_libs}; do case "${libpair}" in ${lib}:*) libpath="${libpair#*:}" && break ;; esac done else libpath="${lib}" fi list_libs="$list_libs $lib" foundone= lib_symbols="$(nm -D --defined-only --format=posix "${libpath}" | awk '$2 ~ /C|R|D|T|W|B|V/ {print $1}' | tr '\n' ' ')" if [ ${CHECK_UNRESOLVED} -eq 1 ]; then # Save the global symbols for this lib libkey "${lib}" setvar "${libkey}" "${lib_symbols}" fi for fct in ${lib_symbols}; do case " ${unresolved_symbols} ${bss_symbols} " in *\ ${fct}\ *) foundone="${fct}" && break ;; esac done if [ -n "${foundone}" ]; then echo "yes... ${foundone}" else echo "no" ret=1 fi done if [ ${CHECK_UNRESOLVED} -eq 1 ]; then # Add in crt1 symbols list_libs="${list_libs} crt1.o" lib_symbols="$(nm --defined-only --format=posix "/usr/lib/crt1.o" | awk '$2 ~ /C|R|D|T|W|B|V/ {print $1}' | tr '\n' ' ')" # Save the global symbols for this lib libkey "crt1.o" setvar "${libkey}" "${lib_symbols}" # Now search libs for all symbols and report missing ones. for sym in ${unresolved_symbols}; do found=0 for lib in ${list_libs}; do libkey "${lib}" eval "lib_symbols=\"\${${libkey}}\"" # lib_symbols now contains symbols for the lib. case " ${lib_symbols} " in *\ ${sym}\ *) [ ${VERBOSE_RESOLVED} -eq 1 ] && echo "Resolved symbol ${sym} from ${lib}" found=1 break ;; esac done if [ $found -eq 0 ]; then echo "Unresolved symbol $sym" ret=1 fi done fi exit ${ret}