generate-fat.sh revision 293297 
1#!/bin/sh
2
3# This script generates the dummy FAT filesystem used for the EFI boot
4# blocks. It uses newfs_msdos to generate a template filesystem with the
5# relevant interesting files. These are then found by grep, and the offsets
6# written to a Makefile snippet.
7#
8# Because it requires root, and because it is overkill, we do not
9# do this as part of the normal build. If makefs(8) grows workable FAT
10# support, this should be revisited.
11
12# $FreeBSD: stable/10/sys/boot/efi/boot1/generate-fat.sh 293297 2016-01-07 02:22:45Z emaste $
13
14FAT_SIZE=1600 			#Size in 512-byte blocks of the produced image
15
16BOOT1_SIZE=128k
17
18#
19# Known filenames
20# amd64: BOOTx64.efi
21# arm64: BOOTaa64.efi
22#
23if [ -z "$1" ]; then
24	echo "Usage: $0 filename"
25	exit 1
26fi
27
28FILENAME=$1
29
30# Generate 800K FAT image
31OUTPUT_FILE=fat.tmpl
32
33dd if=/dev/zero of=$OUTPUT_FILE bs=512 count=$FAT_SIZE
34DEVICE=`mdconfig -a -f $OUTPUT_FILE`
35newfs_msdos -F 12 -L EFI $DEVICE
36mkdir stub
37mount -t msdosfs /dev/$DEVICE stub
38
39# Create and bless a directory for the boot loader
40mkdir -p stub/efi/boot
41
42# Make a dummy file for boot1
43echo 'Boot1 START' | dd of=stub/efi/boot/$FILENAME cbs=$BOOT1_SIZE count=1 conv=block
44
45umount stub
46mdconfig -d -u $DEVICE
47rmdir stub
48
49# Locate the offset of the fake file
50BOOT1_OFFSET=$(hd $OUTPUT_FILE | grep 'Boot1 START' | cut -f 1 -d ' ')
51
52# Convert to number of blocks
53BOOT1_OFFSET=$(echo 0x$BOOT1_OFFSET | awk '{printf("%x\n",$1/512);}')
54
55echo '# This file autogenerated by generate-fat.sh - DO NOT EDIT' > Makefile.fat
56echo '# $FreeBSD: stable/10/sys/boot/efi/boot1/generate-fat.sh 293297 2016-01-07 02:22:45Z emaste $' >> Makefile.fat
57echo "BOOT1_OFFSET=0x$BOOT1_OFFSET" >> Makefile.fat
58
59bzip2 $OUTPUT_FILE
60echo 'FAT template boot filesystem created by generate-fat.sh' > $OUTPUT_FILE.bz2.uu
61echo 'DO NOT EDIT' >> $OUTPUT_FILE.bz2.uu
62echo '$FreeBSD: stable/10/sys/boot/efi/boot1/generate-fat.sh 293297 2016-01-07 02:22:45Z emaste $' >> $OUTPUT_FILE.bz2.uu
63
64uuencode $OUTPUT_FILE.bz2 $OUTPUT_FILE.bz2 >> $OUTPUT_FILE.bz2.uu
65rm $OUTPUT_FILE.bz2
66
67