strings2files.sh

#!/bin/bash
# used this once map lines from a bootloader log to files found in a 
# firmware dump. This is a cheap way to understand stages of the 
# bootloader.
#
# A bit more on that. After extracting all of the firmware parts such
# as file systems and monolithic code or bootloaders, make a log of
# the boot log (if possible, via serial for example) and then feed
# that to this script from the root directory of the extracted firmware.
#
# example:
# cd firmware_extract
# find_strings.sh seriallog.0
# or to remove the verbose logging
# find_strings.sh seriallog.0  2>/dev/null

MINLEN=6
MAXFILES=10

if [ $# -lt 1 ]; then
	echo "provide file with strings as argument (such as a log file)"
	exit 1
fi
cat $1 | head -100 | \
while read line; do
	echo "$line"
	
	left="$line"
	match=""
	while [ 1 ]; do
		[[ $left =~ ([\-_a-zA-Z][\-_\\ a-zA-Z]{$(($MINLEN-2)),}[\-_a-zA-Z])(.*) ]]
		matchtmp="${BASH_REMATCH[1]}"
		if [ "x${matchtmp}" = "x" ]; then
			break; # no match found. done searching
		fi
		if [ ${#matchtmp} -gt ${#match} ]; then
			match="$matchtmp"
		fi
		left="${BASH_REMATCH[2]}"
	done
		
	if [ ${#match} -lt $MINLEN ]; then 
		>&2 printf "### %-40s ###\n" "to short. skip line"
		continue
	fi

	>&2 printf "### %-40s ###\n" "logest match: \"$match\""
	FILES=$(grep -rl "$match" . )
	if [[ "${FILES}" != "" ]]; then
		IFS=$'\n'
		i=1
		echo "##### match: \"$match\""
		for FILE in $FILES; do
			if [ $i -gt $MAXFILES ]; then
				echo "##### ..."
				break
			fi
			echo -ne "##### $FILE\n"
			i=$(($i+1))
		done
	else
		>&2 printf "### %-40s ###\n" "no matched files"
	fi
	
done