#!/bin/bash

#
# Runtime syscall inspector
#
# Copyright (c) 2012 Red Hat <pmoore@redhat.com>
# Author: Paul Moore <paul@paul-moore.com>
#

#
# This library is free software; you can redistribute it and/or modify it
# under the terms of version 2.1 of the GNU Lesser General Public License as
# published by the Free Software Foundation.
#
# This library is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
# for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with this library; if not, see <http://www.gnu.org/licenses>.
#

####
# functions

function verify_deps() {
	[[ -z "$1" ]] && return
	if ! which "$1" >& /dev/null; then
		echo "error: install \"$1\" and include it in your \$PATH"
		exit 1
	fi
}

####
# main

# verify script dependencies
verify_deps strace
verify_deps sed
verify_deps sort
verify_deps uniq

# get the command line arguments
opt_freq=0
opt_args=0
opt_out="/proc/self/fd/1"
while getopts "afo:h" opt; do
	case $opt in
	a)
		opt_args=1
		;;
	f)
		opt_freq=1
		;;
	o)
		opt_out="$OPTARG"
		;;
	h|*)
		echo "usage $0 [-f] [-a] [-o <file>] <command> [<args>]"
		exit 1
	esac
done
shift $(expr $OPTIND - 1)

# generate a temporary output file
raw=$(mktemp -t strace-raw_XXXXXX)
out="$raw-out"

# capture the strace output
strace -o $raw -- $*

# filter the raw strace
if [[ $opt_args -eq 0 ]]; then
	if [[ $opt_freq -eq 0 ]]; then
		cat $raw | sed -e 's/(.*//' | sort -u > $out
	else
		cat $raw | sed -e 's/(.*//' | sort | uniq -c | sort -nr > $out
	fi
else
	if [[ $opt_freq -eq 0 ]]; then
		cat $raw | sed -e 's/)[ \t]*=.*$/)/' \
			| sed -e 's/".*,/"...",/g;s/\/\*.*\*\//.../g' \
			| sed -e 's/0x[a-f0-9]\+/.../g' \
			| sort -u > $out
	else
		cat $raw | sed -e 's/)[ \t]*=.*$/)/' \
			| sed -e 's/".*,/"...",/g;s/\/\*.*\*\//.../g' \
			| sed -e 's/0x[a-f0-9]\+/.../g' \
			| sort | uniq -c | sort -nr > $out
	fi
fi

# display the output
echo "============================================================" > $opt_out
echo "Syscall Report (\"$*\")" >> $opt_out
[[ $opt_freq -eq 1 ]] && echo "   freq syscall" >> $opt_out
echo "============================================================" >> $opt_out
cat $out >> $opt_out

# cleanup and exit
rm -f $raw $out
exit 0