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Forked from robertlinux/populate-extfs.sh
Created July 19, 2013 21:41
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#!/bin/sh
do_usage () {
cat << _EOF
Usage: populate-extfs.sh <source> <device>
Create an ext2/ext3/ext4 filesystem from a directory or file
source: The source directory or file
device: The target device
_EOF
exit 1
}
[ $# -ne 2 ] && do_usage
SRCDIR=${1%%/}
DEVICE=$2
DEBUGFS="debugfs"
{
CWD="/"
find $SRCDIR | while read FILE; do
TGT="${FILE##*/}"
DIR="${FILE#$SRCDIR}"
DIR="${DIR%$TGT}"
# Skip the root dir
[ ! -z "$DIR" ] || continue
[ ! -z "$TGT" ] || continue
if [ "$DIR" != "$CWD" ]; then
echo "cd $DIR"
CWD="$DIR"
fi
# Only stat once since stat is a time consuming command
STAT=$(stat -c "TYPE=\"%F\";DEVNO=\"0x%t 0x%T\";MODE=\"%f\";U=\"%u\";G=\"%g\"" $FILE)
eval $STAT
case $TYPE in
"directory")
echo "mkdir $TGT"
;;
"regular file" | "regular empty file")
echo "write $FILE $TGT"
;;
"symbolic link")
LINK_TGT=$(readlink $FILE)
echo "symlink $TGT $LINK_TGT"
;;
"block special file")
echo "mknod $TGT b $DEVNO"
;;
"character special file")
echo "mknod $TGT c $DEVNO"
;;
"fifo")
echo "mknod $TGT p"
;;
*)
echo "Unknown/unhandled file type '$TYPE' file: $FILE" 1>&2
;;
esac
# Set the file mode
echo "sif $TGT mode 0x$MODE"
# Set uid and gid
echo "sif $TGT uid $U"
echo "sif $TGT gid $G"
done
# Handle the hard links.
# Save the hard links to a file, use the inode number as the filename, for example:
# If a and b's inode number is 6775928, save a and b to /tmp/tmp.VrCwHh5gdt/6775928.
INODE_DIR=`mktemp -d` || exit 1
for i in `find $SRCDIR -type f -links +1 -printf 'INODE=%i###FN=%p\n'`; do
eval `echo $i | sed 's$###$ $'`
echo ${FN#$SRCDIR} >>$INODE_DIR/$INODE
done
# Use the debugfs' ln and "sif links_count" to handle them.
for i in `ls $INODE_DIR`; do
# The link source
SRC=`head -1 $INODE_DIR/$i`
# Remove the files and link them again except the first one
for TGT in `sed -n -e '1!p' $INODE_DIR/$i`; do
echo "rm $TGT"
echo "ln $SRC $TGT"
done
LN_CNT=`cat $INODE_DIR/$i | wc -l`
# Set the links count
echo "sif $SRC links_count $LN_CNT"
done
rm -fr $INODE_DIR
} | $DEBUGFS -w -f - $DEVICE
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