#!/bin/bash
#
# Common functions to copy binaries and their dependancies.
#
############################################################
# This will parse the output of ldd on given binaries
# and echo the location of these libs to STDOUT
# The output of this function has to be used in some
# way, it only echos!
#
# About local search:
# It is required that we can search for the dynamic
# libraries in a specific directory, namely the one
# where we (potentially) built the binary. If a
# corresponding library is found, it should take
# precedence over ones found on the system.
# This can be done by using the '-l' switch, see below.
#
############################################################
# We use a blacklist mechanism to exclude common libraries.
# This improves runtime quite a bit...
BLACKLIST="ld-linux linux-gate linux-vdso libc.so"
# Initialise flag and path for local search
LOCALSEARCH=0
LOCALSEARCHDIR=""
# replace ' ' by '|' in the blacklist, so grep can use it directly.
CURRENT_BLACKLIST=$(echo ${BLACKLIST} | sed 's/ /\\|/g')
############################################################
#
# Usage:
# get_dynamic_dependencies [-l <searchdir>] <binary_list>
# * the list must be seperated by spaces
# * the search for lib needed by a binary can be done locally,
# using the -l <searchdir> option
#
# Ouput:
# Will simply echo list of required libraries
get_dynamic_dependencies() {
# check if local search is activated by the '-l' switch
# if so the following argument is the path.
if [ "x$1" == "x-l" ]; then
LOCALSEARCH=1
shift
[ ! -d "$1" ] && perror "Directory '$1' does not exist, exiting."
LOCALSEARCHDIR="$1"
shift
fi
# main loop over the list of binaries
while [ $# != 0 ]; do
local BINARY="$1"
shift
# now run ldd on it and save the output in $LDD_OUT
local LDD_OUT="ldd_output"
if ldd "$BINARY" > "$LDD_OUT"; then
# Case 1: file is a dynamic executable
for LIB in $(grep -v "${CURRENT_BLACKLIST}${REQUIRED_LDD_BLACKLIST}" "$LDD_OUT" | awk '{print $1 $2 $3}'); do
# split the entry into an array, ex:
# libm.so.6 => /lib/libm.so.6 would be split into:
# LIBLINK[0] LIBLINK[1]
local LIBLINK=(${LIB//=>/ })
# call helper function to find the correct lib
lib_search
done
#TODO: check if "statically linked" is output
else
# Case 2: not a dynamic, do nothing
pdebug "\t\t\t(Not a dynamic.)"
rm -f "$LDD_OUT"
continue
fi
rm -f "$LDD_OUT"
done
}
############################################################
#
# Usage:
# lib_search
#
# Output:
# List of the path including any possible symbolic links
# of the found libraries.
#
# Note: This function takes no argument. It takes the library
# to look for from the local array LIBLINK.
# If the local was activated in get_dynamic_dependencies
# this will search for the library in LOCALSEARCHDIR first.
# If its not found, then it will look system-wide.
lib_search() {
# if activated, start by searching the lib locally
if [ "x$LOCALSEARCH" == "x1" ]; then
cd "$LOCALSEARCHDIR"
local LOCAL_MATCHES=$(find . -name "${LIBLINK[0]}") # | awk -F '.' '{print $1}')".so\*)
cd - >/dev/null
if [ "x${LOCAL_MATCHES}" != "x" ]; then
for LOCALLIB in ${LOCAL_MATCHES}; do
get_link_chain "${LOCALSEARCHDIR}/${LOCALLIB}" "${LOCALSEARCHDIR}"
get_dynamic_dependencies -l "${LOCALSEARCHDIR}" "${LOCALLIB}"
CURRENT_BLACKLIST+="\|${LIBLINK[0]}"
done
# found the libs, we are done
return
fi
# mark local search as done
fi
# search the lib on the system since it was not found earlier
if [ ! -z ${LIBLINK[1]} ] && [ "x${LIBLINK[1]}" != "xnot" ]; then
# get chain of symlink for that lib
get_link_chain "${LIBLINK[1]}"
CURRENT_BLACKLIST+="\|${LIBLINK[1]}"
else
pwarning "\t\tLib '${LIBLINK[0]}' from required dir '$ENTRY' neither found in build directory nor on this system."
pwarning "\t\tIf this lib is not supplied by another module, this module will probably fail in your final system"
fi
}
############################################################
#
# Usage:
# get_link_chain <link> [prefix]
# * <link> must be in absolute form-
# * [prefix] is the prefix to strip from the ouput.
#
# Output:
# Lists the symlink chain until a hardlink is found.
#
get_link_chain() {
# sanity checks
if [[ "$1" == /* ]]; then
[ -e $1 ] || perror "get_link_chain: no such file: $1"
else
perror "get_link_chain() requires absolute paths, given: $1"
fi
if [ $# == 2 ] ; then
[ ! -d $2 ] && perror "get_link_chain: $2 is not a directory."
# got a prefix
local PREFIX=$(readlink -f $2)
else
# mark prefix as not set
local PREFIX="notset"
fi
# canonalize
local LINK=$(canonicalize $1)
local CHAIN="$LINK"
# write the first link in the chain
if [ "x$PREFIX" != "x" -a "x$PREFIX" != "xnotset" ]; then
if [ "x${LINK#$PREFIX}" == "x${LINK}" ]; then
# prefix was not in the link
echo "$LINK"
else
# prefix was in the link
echo ./"${LINK#$PREFIX}"
fi
else
# no prefix, copy like it is
echo "$LINK"
fi
# now we check for symlinks
local TRY=0
while [ -L "$LINK" ] && [ $TRY -lt 10 ]; do
let TRY=TRY+1
# save the directory prefix
CURRENTDIR=$(dirname "${LINK}")
# first follow the link
LINK=$(readlink "$LINK")
CHAIN+=" -> $LINK"
# $LINK can be absolute or relative, check cases
[[ "$LINK" == /* ]] || LINK=$(canonicalize "$CURRENTDIR"/"${LINK}")
# write the first link in the chain
if [ "x$PREFIX" != "x" -a "x$PREFIX" != "xnotset" ]; then
if [ "x${LINK#$PREFIX}" == "x${LINK}" ]; then
# prefix was not in the link
echo "$LINK"
else
# prefix was in the link
echo ./"${LINK#$PREFIX}"
fi
else
# no prefix, copy like it is
echo "$LINK"
fi
done
pdebug "\t\t$CHAIN"
}
############################################################
#
# Usage:
# list_basic_libs
#
# Output:
# list the path of following basic system libraries:
# - libc.so, ld-linux.so
#
list_basic_libs() {
for i in $(ldd ${SHELL})
do
[ $(echo $i | grep '^/' | grep -c ld) -eq 1 -o $(echo $i | grep '^/' | grep -c libc.so) -eq 1 ] && get_link_chain $i
done
}
