9990-select-eth-device.sh: check carrier, pick NIC

Improve the mechanism to check the carrier to pick from
multiple network interfaces. This is based on the patch from
Michal Zatloukal.
Ref: https://sourceforge.net/p/clonezilla/bugs/298/

diff --git a/components/9990-select-eth-device.sh b/components/9990-select-eth-device.sh
index c8f36b0..8d7ef84 100755 (executable)
--- a/components/9990-select-eth-device.sh
+++ b/components/9990-select-eth-device.sh
@@ -1,5 +1,30 @@
 #!/bin/sh
 
+Wait_for_carrier ()
+{
+       # $1 = network device
+       echo -n "Waiting for link to come up on $1... "
+       ip link set $1 up
+       for step in $(seq 1 15)
+       do
+               carrier=$(cat /sys/class/net/$1/carrier \
+               2>/dev/null)
+               case "${carrier}" in
+                       1)
+                       echo -e "\nLink is up"
+                       return
+                       ;;
+                       *)
+                       # Counter
+                       echo -n "$step "
+                       ;;
+               esac
+               sleep 1
+       done
+       echo -e "\nError - carrier not detected on $1."
+       ip link set $1 down
+}
+
 Select_eth_device ()
 {
        # Boot type in initramfs's config
@@ -46,6 +71,7 @@ Select_eth_device ()
                then
                        # only one interface : no choice
                        echo "DEVICE=$l_interfaces" >> /conf/param.conf
+                       Wait_for_carrier $l_interfaces
                        return
                fi
 
@@ -57,6 +83,7 @@ Select_eth_device ()
                                NETDEV="${ARGUMENT#live-netdev=}"
                                echo "DEVICE=$NETDEV" >> /conf/param.conf
                                echo "Found live-netdev parameter, forcing to to use network device $NETDEV."
+                               Wait_for_carrier $NETDEV
                                return
                                ;;
                        esac
@@ -75,6 +102,7 @@ Select_eth_device ()
                        # ATTR{carrier} is not set if this is not done
                        echo -n " $interface ?"
                        ipconfig -c none -d $interface -t 1 >/dev/null 2>&1
+                       sleep 1
                done
 
                echo ''
@@ -83,6 +111,7 @@ Select_eth_device ()
                do
                        for interface in $l_interfaces
                        do
+                               ip link set $interface up
                                carrier=$(cat /sys/class/net/$interface/carrier \
                                        2>/dev/null)
                                # link detected