kern


1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130

#!/bin/sh

set -e

SRCDIR=/usr/src
KERNFRAG=${KERNFRAG:-/etc/kernfrag}

errx() {
	printf "kern: %s\n" "$@" >&2
	exit 1
}

has_boot_mount() {
	awk '{print $2}' /etc/fstab | grep -q ^/boot$
}

is_boot_mounted() {
	mountpoint -q /boot
}

get_latest_kernel() {
	eselect --brief kernel list | tail -n1
}

get_current_kernel() {
	basename "$(eselect --brief kernel show 2>/dev/null)"
}

set_kernel() {
	kern=${1:-$(get_latest_kernel)}
	current=$(get_current_kernel)
	kerndir=$SRCDIR/$kern

	if test ! -d "$kerndir"; then
		errx "No such file or directory: $kerndir"
	fi

	if test "$kern" = "$current"; then
		errx "Latest kernel already set: $kern"
	fi

	printf "Setting active kernel: %s\n" "$kern"

	sudo eselect kernel set "$kern"
	sudo chown -R "$(id -un)":"$(id -gn)" "$kerndir"
}

config_kernel() {
	host=${1:-$(hostname)}

	if test ! -d "$KERNFRAG"; then
		errx "No such file or directory: $KERNFRAG"
	fi

	printf "Starting merge for %s...\n\n" "$host"

	awk -v prefix="$KERNFRAG/fragments/" '{print prefix $0}' \
		"$KERNFRAG/templates/base" "$KERNFRAG/templates/$host" | xargs scripts/kconfig/merge_config.sh
}

diff_kernel() {
	diff=${1:-/proc/config.gz}
	nvim -d .config "$diff"
}

build_kernel() {
	make -j"$(nproc)"
}

install_kernel() {
	if has_boot_mount && ! is_boot_mounted; then
		sudo mount /boot
	fi
	sudo make install modules_install
}

post_install_kernel() {
	sudo emerge --ask=n @module-rebuild
}

clean_kernel() {
	sudo eclean-kernel -An3
}

test_diff() {
	dt=$(mktemp)
	zcat /proc/config.gz | sed -nE '/^(# )?CONFIG_.*/p' > "$dt"
	sed -nE '/^(# )?CONFIG_.*/p' .config | diff -q "$dt" -
	diffr=$?
	rm -f "$dt"
	if test $diffr -ne 0; then
		diff_kernel
		printf "Continue? [y/N] "
		read -r response
		if test "$response" = "y"; then
			return 0
		fi
	fi
	return $diffr
}

all() {
	set_kernel &&
	cd /usr/src/linux &&
	config_kernel &&
	test_diff &&
	build_kernel &&
	install_kernel &&
	post_install_kernel &&
	clean_kernel
}

if test $# -eq 0; then
	all
	exit 0
fi

cmd=$1
shift

case $cmd in
	set) set_kernel "$@";;
	config) config_kernel "$@";;
	diff) diff_kernel "$@";;
	build) build_kernel;;
	install) install_kernel;;
	postinst) post_install_kernel;;
	clean) clean_kernel;;
	all) all;;
esac