vigpg

#!/bin/bash
# Edit a file that has been encoded with gpg.

# this gets us some functions and variables needed by various programs
if [[ -e "${HOME}/docs/code/library.sh" ]] ; then
	source "${HOME}/docs/code/library.sh"
fi

function usage {
	echo "Usage: $0 FILE"
}

# exit after printing first argument to this function
function die {
    # echo the first argument
    echo $1

    exit 1
}

# this will get the location of $1 (from the $PATH)
function get_location_of_file()
{
    tmp_filename=$1
    tmp_fullpath=`which ${tmp_filename} 2>/dev/null`

    if [ -n "${tmp_fullpath}" ]
    then
        echo ${tmp_fullpath}
    fi
}

# this takes an argument list of filenames and outputs
# the first one that can be found on $PATH.
# It outputs a full path to the file.
function get_correct_filename_from_choices()
{
    while ((1))
    do
        # break if there are no more arguments
        if [ -z $1 ]
        then
            break
        fi

        # get the full path of the filename
        tmp_filename=$1
        shift
        tmp_fullpath=`get_location_of_file ${tmp_filename}`

        # if this program is on $PATH, echo it's full path
        # and get out of this loop
        if [ -n "${tmp_fullpath}" ]
        then
            echo ${tmp_fullpath}
            break
        fi
    done
}

GPG=`get_correct_filename_from_choices "gpg1" "gpg"`

# make sure there is only one argument
if [ "$#" != "1" ]
then
	usage
	exit 1
fi

file_name=$1

# make sure the argument is a file
[[ -f $file_name ]] || die "ERROR! $file_name is not a file."

# get us a temp file
temp_file=`mktemp puppies.XXXXXX`

# read in password

read -s -p "Password: " password
echo 

# unencrypt the file and put it's output in tempfile
echo $password | $GPG --passphrase-fd 0 -d ${file_name} > ${temp_file} || 
	die "ERROR! Could not decrypt $file_name"

# edit the tempfile
$EDITOR ${temp_file} || 
	die "ERROR! Could not edit the decrypted file ${temp_file}"

# reencrypt the tempfile
echo $password | $GPG --passphrase-fd 0 -c -o ${file_name} ${temp_file} || 
	die "ERROR! Could not reencrypt ${temp_file} to ${file_name}."

# delete the tempfile
rm ${temp_file}