[Ovirt-devel] [PATCH] Prevents duplicate DNS and NTP server entries.

[Darryl L. Pierce]

Checks any entered address for DNS and NTP servers against previously
entered ones in order to prevent duplicates.

Resolves: rhbz#555373

Signed-off-by: Darryl L. Pierce <dpierce at redhat.com>
---
 scripts/ovirt-config-networking |   46 +++++++++++++++++++++++++-------------
 scripts/ovirt-functions         |    7 ++++++
 2 files changed, 37 insertions(+), 16 deletions(-)

diff --git a/scripts/ovirt-config-networking b/scripts/ovirt-config-networking
index 6c2bd21..a4e0ebd 100755
--- a/scripts/ovirt-config-networking
+++ b/scripts/ovirt-config-networking
@@ -357,8 +357,9 @@ function configure_dns
                 for dns in first second; do
                     while true; do
                         printf "\n"
-                        read -ep "Please enter the ${dns} DNS server (or ENTER to exit): "
-                        if [[ -z "${REPLY}" ]]; then
+                        read -erp "Please enter the ${dns} DNS server (or ENTER to exit): "
+                        local ADDRESS=$(trim_whitespace $REPLY)
+                        if [[ -z "${ADDRESS}" ]]; then
                             if [[ -z "${DNS}" ]]; then
                                 printf "\nAborted...\n"
                                 return
@@ -366,15 +367,19 @@ function configure_dns
                                 break
                             fi
                         fi
-                        if is_valid_ipv4 $REPLY; then
+                        if is_valid_ipv4 $ADDRESS; then
                             if [[ -z "${DNS}" ]]; then
-                                DNS="${REPLY}"
-                            elif [[ -n "${REPLY}" ]]; then
-                                DNS="${DNS}:${REPLY}"
+                                DNS="${ADDRESS}"
+                            elif [[ -n "${ADDRESS}" ]]; then
+                                if [[ ! $DNS =~ "${ADDRESS}" ]]; then
+                                    DNS="${DNS}:${ADDRESS}"
+                                    break
+                                else
+                                    printf "${ADDRESS} is already defined as a DNS server.\n"
+                                fi
                             fi
-                            break
                         else
-                            printf "${REPLY} is an invalid address.\n"
+                            printf "${ADDRESS} is an invalid address.\n"
                         fi
                     done
                 done
@@ -403,19 +408,28 @@ function configure_ntp
 {
     local AUTO=$2
     if [[ "$AUTO" == "AUTO" && -n "$OVIRT_NTP" ]]; then
-	NTPSERVERS=$OVIRT_NTP
+        NTPSERVERS=$OVIRT_NTP
     else
-	NTPSERVERS=""
+        NTPSERVERS=""
     fi
 
     if [ -z "$AUTO" ]; then
         if has_configured_interface true; then
-	    while true; do
-	        read -ep "Enter an NTP server (hit return when finished): "
+            while true; do
+                read -rp "Enter an NTP server (hit return when finished): "
+                local ADDRESS=$(trim_whitespace $REPLY)
 
-	        if [ -z "$REPLY" ]; then break; fi
-                NTPSERVERS="${NTPSERVERS}:${REPLY}"
-	    done
+                if [ -z "${ADDRESS}" ]; then break; fi
+                if is_valid_ipv4 $address; then
+                    if [[ ! $NTPSERVERS =~ $address ]]; then
+                        NTPSERVERS="${NTPSERVERS}:${ADDRESS}"
+                    else
+                        printf "${ADDRESS} is already defined as an NTP server.\n"
+                    fi
+                else
+                    printf "${ADDRESS} is an invalid address.\n"
+                fi
+            done
         fi
     fi
 }
diff --git a/scripts/ovirt-functions b/scripts/ovirt-functions
index 482441a..d8aa008 100644
--- a/scripts/ovirt-functions
+++ b/scripts/ovirt-functions
@@ -665,6 +665,13 @@ add_if_not_exist() {
         || echo "$string" >> "$file"
 }
 
+# $1 - the string to be trimmed
+trim_whitespace () {
+    local text=${1}
+
+    printf "$text" | awk '{gsub(/^[ ]*/,"",$0); gsub(/[ ]*$/,"",$0) ; print }'
+}
+
 is_numeric() {
     printf "$1" | grep -q -E '^[0-9]+$'
 }
-- 
1.6.6.1