gdbGetStrippedSymbols.sh

#!/bin/sh
# gdbGetStrippedSymbols.sh
# @author Dominik Hadl (@dominikhadl)
# @description This script automates the setup of gdb on a stripped applicaiton adds symbols. It uses objc-symbols to get the symbols, 
#             then SymTabCreator and finally creates a command that is automatically loaded into gdb on start.
# @license Licensed under WTFPL license (see http://www.wtfpl.net/txt/copying/ for full license).
# @dependencies 
#  			1. objc-symbols
#			2. SymTabCreator
#			3. gdb (really non-obvious)
# @usage	This script can by used by running this command.
#			gdb_symbols_script.sh <application>
############################################################

################################
# Helpers

function usage
{
	DDP_FILENAME=`basename ${0##*/}`
	echo "usage: ${DDP_FILENAME} <application>"
}

function dependencyIsMissing
{
	if [[ $# == 1 ]]; then
		echo "Dependency (${1}) is missing. Please install it - preferably into /usr/bin."
	fi
	exit 1
}

################################


## Main Execution
################################

# Check if there is a correct number of arguments
if [[ $# == 1 ]]; then
	
	# Check if specified file exists
	if [ -e "$1" ]; then
		
		# Check if commands/dependencies exists
		# 1. gdb (essential)
		# 2. class-dump (almost essential)
		# 3. objc-symbols (class-dump extension)
		# 4. SymTabCreator (for loading symbols into gdb)
		command -v gdb > /dev/null || dependencyIsMissing "gdb"	
		command -v objc-symbols > /dev/null || dependencyIsMissing "objc-symbols"
		command -v SymTabCreator > /dev/null || dependencyIsMissing "SymTabCreator"
		
		# Create Variables
		# 1. Set temporary directory path with .stabs and gdb commands
		# 2. Get the file name without extension
		# 3. Create the path for the .stabs file in temporary dir
		DDP_TMPDIR="/tmp/ddp_gdbcommand" 						
		DDP_FILENAME=`basename "${1%.*}"`						
		DDP_SYMBOL_FILE="${DDP_TMPDIR}/${DDP_FILENAME}.stabs"	
	
		# Execute commands
		# 1. Create the temporary directory
		# 2. Create the symbolic table
		# 3. Save commands for gdb to file
		mkdir "${DDP_TMPDIR}"
		objc-symbols "${1}" | SymTabCreator -o "$DDP_SYMBOL_FILE"
		echo "symbol-file ${DDP_SYMBOL_FILE}" > "${DDP_TMPDIR}/gdbcommands"
	
		# Start gdb with the symbol file
		gdb --silent --command="${DDP_TMPDIR}/gdbcommands" "${1}"
	
		# Cleanup
		# Delete the temporary directory including its contents
		rm -rf "${DDP_TMPDIR}"
	
	else
		echo "File does not exist. Please provide a valid file."
		exit 1
	fi
	
elif [[ $# > 1 ]]; then
	
	# Too many arguments specified
	echo "Too many arguments."
	usage
	exit 1
	
else
	
	# No argument specified
	usage
	exit 1
	
fi