usb.sh can choose between multiple devices

1 files changed, 24 insertions, 4 deletions

diff --git a/src/usb.sh b/src/usb.sh
index 55d8b48..991f553 100755
--- a/src/usb.sh
+++ b/src/usb.sh
@@ -2,6 +2,10 @@
 
 die() { printf "%s: Error: %s\n" "$0" "$*" >&2; exit 1; }
 
+ECHO() { printf "%s\n" "$*" >&2; }
+
+PRINTF() { printf "$@" >&2; }
+
 whole_device()
 {
     case "$1" in
@@ -16,7 +20,7 @@ whole_device()
 confirm_usb()
 {
     local msg="This will completely overwrite device:\n\n\t%s\n\nType 'yes' to confirm.\nContinue? "
-    printf "$msg" "$1" >&2
+    PRINTF "$msg" "$1"
     read line
     case "$line" in
         [yY][eE][sS]) return ;;
@@ -37,9 +41,25 @@ choose_usb()
         die "no usb device found"
     elif [ $# = 1 ]; then
         confirm_usb "$1" || die impossible
-        USB=$(readlink -f "$1")
+        USB=$1
     else
-        die "multiple USB devices connected and choice between them is unimplemented.  ($*)"
+        ECHO
+        PRINTF "%s\n" "The following candidate target devices have been found:"
+        i=0
+        for dev; do
+            i=$((i+1))
+            PRINTF "\n\n\t%2i. %s\n" $i "$dev"
+        done
+        PRINTF "%s\n\n" '' "Choose a device by its number, from 1 to $#, then press enter." "To abort, press CTRL-C."
+        PRINTF "\n%s" 'Your choice: '
+        read line
+        case "$line" in
+            [1-9]|[1-9][0-9])
+                [ $line -le $# -a $line -ge 1 ] || die "Invalid argument (out of range): $line"
+                USB=${!line}
+                ;;
+            *) die "Invalid argument: $line" ;;
+        esac
     fi
 }
 
@@ -49,5 +69,5 @@ choose_cdrom()
 }
 
 choose_usb
-echo $USB
+[ "$USB" ] && readlink -f "$USB"