Question

I have this bash code:

#!/bin/bash



###################################################
# Variables
#
BACKIFS=$IFS
IFS=$'\n'
db_file="$PWD/test"
path_db="$PWD"
check_first_start="$PWD/status"
num_args=$#
###################################################


###################################################
# Fist time that program start
#
function check_before_start(){
if [ ! -f "$path_db/status" ];then
    pass_2=$(yad --form --field "Password:H" --field "Retype Password:H" --separator="@_@" --title "Password" --image="dialog-password")
    if [ $(echo $pass_2 | awk -F"@_@" '{print $1}') != $(echo $pass_2 | awk -F"@_@" '{print $2}') ];then
        yad --title "Errore" --text "Le password sono differenti, riprovare..."
        check_before_start
    fi
    pass=$(echo $pass_2 | awk -F"@_@" '{print $1}')
    touch "$path_db/status"
fi
type_of=$(file $db_file | cut -f2 -d':' | sed '/ /s/^ //' | cut -f1 -d' ')
if [ "$type_of" = "ASCII" ]; then
    pass_2=$(yad --form --field "Password:H" --field "Retype Password:H" --separator="@_@" --title "Password" --image="dialog-password")
    if [ $(echo $pass_2 | awk -F"@_@" '{print $1}') != $(echo $pass_2 | awk -F"@_@" '{print $2}') ];then
        yad --title "Errore" --text "Le password sono differenti, riprovare..."
        check_before_start
    fi
    pass=$(echo $pass_2 | awk -F"@_@" '{print $1}') 
    encrypt_db
fi
}
###################################################


###################################################
# Check exit status
#
function exit_script(){
if [ $? != 0 ] ; then
    type_of=$(file $db_file | cut -f2 -d':' | sed '/ /s/^ //' | cut -f1 -d' ')
    if [ "$type_of" = "ASCII" ]; then
        encrypt_db
    fi
    exit 0
fi
}
###################################################


###################################################
# Encryption functions
#
function encrypt_db(){
echo $pass | gpg --passphrase-fd 0 -o $path_db/enc_db --cipher-algo=aes256 -c $db_file
mv $path_db/enc_db $db_file
}
###################################################


###################################################
# Decryption functions
#
function check_gpg_pwd_decrypt(){
if [ $? != 0 ] ; then
    yad --title "Errore Password" --text "È stata inserita una password errata, riprovare..." --width=450 --height=150
    decrypt_db
fi
}

function decrypt_db(){
pass=$(yad --form --field "Password:H" --separator="" --title "Password" --image="dialog-password")
echo $pass | gpg --passphrase-fd 0 -o $path_db/out_db --cipher-algo=aes256 -d $db_file
check_gpg_pwd_decrypt
mv $path_db/out_db $db_file
}
###################################################


###################################################
# Read data from db
function read_data_from_db(){
choosed_num=$(cat $db_file | sed -n ${line}'p' | cut -f${c1},${c2} -d'.' | tr '.' ' ')
cifra_1=$(echo $choosed_num | cut -f1 -d' ')
cifra_2=$(echo $choosed_num | cut -f2 -d' ')
yad --text "Riga -------><b>${line}</b>\nCifra $c1: --><b>$cifra_1</b>\nCifra $c2: --><b>$cifra_2</b>"
}
###################################################


###################################################
# Read from user the line, c1 and c2 numbers and check these values
#
function input_info(){
info=$(yad --form --field "Numero riga" --field "Prima cifra" --field "Seconda cifra" --separator="-" --title "Input Info")
line=$(echo $info | cut -f1 -d'-')
c1=$(echo $info | cut -f2 -d'-')
c2=$(echo $info | cut -f3 -d'-')
if [ $line -lt 1 ] || [ $line -gt 32 ]; then
    yad --text "Errore: il numero di linea deve essere compreso fra 1 e 32" --title "Errore"
    input_info
fi
if [ $c1 -lt 1 ] || [ $c1 -gt 4 ] || [ $c2 -lt 1 ] || [ $c2 -gt 4 ]; then
    yad --text "Errore: le cifre devono essere comprese fra 1 e 4" --title "Errore"
    input_info
fi
}
###################################################


###################################################
# Main
check_before_start
input_info
decrypt_db
read_data_from_db
encrypt_db
exit 0
###################################################

I have a problem because if I input a wrong password I get this error error: cannot mv file.
I don’t know why but this script executes the mv command (inside the decrypt_db function) 2 times O.o

I cannot understand how to fix it and how it is possible that the decrypt_db has this behavior.

Answer 1

When the wrong password is entered, function check_before_start calls itself once more. Each of those invocations arrive at the call to encrypt_db, which in turn calls mv, so it is called two times. You need to exit ot of the outer invocation of check_before_start (e.g. using return) after it calls itself the second time due to invalid password.