mk_mmc.sh: Clean up checking for installed commands.

Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: Robert Nelson <robertcnelson@gmail.com>

mk_mmc.sh

@@ -141,53 +141,36 @@ if parted -v | grep parted | grep 2.[1-3] >/dev/null ; then
 fi
 }
 
-function detect_software {
-
-echo "This script needs:"
-echo "Ubuntu/Debian: sudo apt-get install uboot-mkimage wget dosfstools parted"
-echo "Fedora: as root: yum install uboot-tools wget dosfstools parted dpkg patch"
-echo "Gentoo: emerge u-boot-tools wget dosfstools parted dpkg"
-echo ""
-
-unset NEEDS_PACKAGE
-
-if [ ! $(which mkimage) ];then
- echo "Missing uboot-mkimage"
- NEEDS_PACKAGE=1
-fi
-
-if [ ! $(which wget) ];then
- echo "Missing wget"
- NEEDS_PACKAGE=1
-fi
-
-if [ ! $(which mkfs.vfat) ];then
- echo "Missing mkfs.vfat"
- NEEDS_PACKAGE=1
-fi
-
-if [ ! $(which parted) ];then
- echo "Missing parted"
- NEEDS_PACKAGE=1
-fi
+function check_for_command {
+	if ! which "$1" > /dev/null ; then
+		echo -n "You're missing command $1"
+		NEEDS_COMMAND=1
+		if [ -n "$2" ] ; then
+			echo -n " (consider installing package $2)"
+		fi
+		echo
+	fi
+}
 
-if [ ! $(which dpkg) ];then
- echo "Missing dpkg"
- NEEDS_PACKAGE=1
-fi
+function detect_software {
+	unset NEEDS_COMMAND
 
-if [ ! $(which patch) ];then
- echo "Missing patch"
- NEEDS_PACKAGE=1
-fi
+	check_for_command mkimage uboot-mkimage
+	check_for_command mkfs.vfat dosfstools
+	check_for_command wget wget
+	check_for_command parted parted
+	check_for_command dpkg dpkg
+	check_for_command patch patch
 
-if [ "${NEEDS_PACKAGE}" ];then
+	if [ "${NEEDS_COMMAND}" ] ; then
 		echo ""
- echo "Your System is Missing some dependencies"
+		echo "Your system is missing some dependencies"
+		echo "Ubuntu/Debian: sudo apt-get install uboot-mkimage wget dosfstools parted"
+		echo "Fedora: as root: yum install uboot-tools wget dosfstools parted dpkg patch"
+		echo "Gentoo: emerge u-boot-tools wget dosfstools parted dpkg"
 		echo ""
 		exit
-fi
-
+	fi
 }
 
 function rcn-ee_down_use_mirror {