Looks for a given function in a number of files. Glorified wrapper for ctags.

findfn

#!/bin/bash

print_usage()
{
	echo "Usage: findfn [OPTION]... [FUNCTION] [FILE]..."
	echo "Example 1: findfn foo main.c"
	echo "Example 2: findfn foo main.c foo.c"
}

check_usage()
{
	while getopts h option; do
		case $option in
			h) print_usage
			exit 0
			;;
			?) print_usage
			exit 2
			;;
		esac
	done
}

# Search for definition of $1 in list of files $2
find_fn_def_with_ctags()
{
	fn=$1
	files=$2
	fn_def=

	for file in $files; do
		if [ -e $file ]; then
			# Exuberant ctags only?
			line=$(ctags -x --c-kinds=f $file | grep [\ ]$fn[\ \(])
			if [ -z "$line" ]; then
				continue
			fi
			lineno=$(echo $line | cut -d" " -f3)
			fn_def=$(sed -n "${lineno}p" $file)
			prevlineno=$((lineno - 1))
			if [[ "$fn_def" =~ ^"$fn" ]]; then
				fn_def_ret=$(sed -n "${prevlineno}p" $file)
				fn_def="$fn_def_ret $fn_def"
			fi
			nextlineno=$((lineno + 1))
			while [[ ! "$fn_def" =~ "{" ]]; do
				fn_def+=$(sed -n "${nextlineno}p" $file)
				nextlineno=$((nextlineno + 1))
			done
			fn_def=$(echo $fn_def | cut -d"{" -f1)
			# Strip unneeded spaces from function definition
			fn_def=$(echo $fn_def | sed "s/^ //; s/ $//" | \
			sed "s/$fn (/$fn(/; s/$fn( /$fn(/; s/ )$/)/" | \
			sed "s/ ,/,/g")
			echo File $file, line $lineno: $fn_def
		fi
	done
}

check_usage $@
fn=$1
shift
files=$@

find_fn_def_with_ctags $fn "$files"