embed_mfs: add error handling, usage

Ensure that we are called with two arguments, and that the output file
is writable. Also, if we cannot find the mfs section report the output
file name rather than "kernel", as this script may be used with other
than kernels.

Sponsored by:	The FreeBSD Foundation
This commit is contained in:
Ed Maste 2017-10-17 21:13:26 +00:00
parent b394cd1e28
commit 0bf94a089d
Notes: svn2git 2020-12-20 02:59:44 +00:00
svn path=/head/; revision=324707

View File

@ -32,13 +32,22 @@
# $2: MFS image filename
#
if [ $# -ne 2 ]; then
echo "usage: $(basename $0) target mfs_image"
exit 0
fi
if [ ! -w "$1" ]; then
echo $1 not writable
exit 1
fi
mfs_size=`stat -f '%z' $2 2> /dev/null`
# If we can't determine MFS image size - bail.
[ -z ${mfs_size} ] && echo "Can't determine MFS image size" && exit 1
sec_info=`elfdump -c $1 2> /dev/null | grep -A 5 -E "sh_name: oldmfs$"`
# If we can't find the mfs section within the given kernel - bail.
[ -z "${sec_info}" ] && echo "Can't locate mfs section within kernel" && exit 1
[ -z "${sec_info}" ] && echo "Can't locate mfs section within $1" && exit 1
sec_size=`echo "${sec_info}" | awk '/sh_size/ {print $2}' 2> /dev/null`
sec_start=`echo "${sec_info}" | awk '/sh_offset/ {print $2}' 2> /dev/null`