xref: /linux/scripts/adjust_autoksyms.sh (revision cd195bc4)
1#!/bin/sh
2# SPDX-License-Identifier: GPL-2.0-only
3
4# Script to update include/generated/autoksyms.h and dependency files
5#
6# Copyright:	(C) 2016  Linaro Limited
7# Created by:	Nicolas Pitre, January 2016
8#
9
10# Update the include/generated/autoksyms.h file.
11#
12# For each symbol being added or removed, the corresponding dependency
13# file's timestamp is updated to force a rebuild of the affected source
14# file. All arguments passed to this script are assumed to be a command
15# to be exec'd to trigger a rebuild of those files.
16
17set -e
18
19cur_ksyms_file="include/generated/autoksyms.h"
20new_ksyms_file="include/generated/autoksyms.h.tmpnew"
21
22info() {
23	if [ "$quiet" != "silent_" ]; then
24		printf "  %-7s %s\n" "$1" "$2"
25	fi
26}
27
28info "CHK" "$cur_ksyms_file"
29
30# Use "make V=1" to debug this script.
31case "$KBUILD_VERBOSE" in
32*1*)
33	set -x
34	;;
35esac
36
37# We need access to CONFIG_ symbols
38. include/config/auto.conf
39
40# Generate a new symbol list file
41$CONFIG_SHELL $srctree/scripts/gen_autoksyms.sh "$new_ksyms_file"
42
43# Extract changes between old and new list and touch corresponding
44# dependency files.
45changed=$(
46count=0
47sort "$cur_ksyms_file" "$new_ksyms_file" | uniq -u |
48sed -n 's/^#define __KSYM_\(.*\) 1/\1/p' | tr "A-Z_" "a-z/" |
49while read sympath; do
50	if [ -z "$sympath" ]; then continue; fi
51	depfile="include/ksym/${sympath}.h"
52	mkdir -p "$(dirname "$depfile")"
53	touch "$depfile"
54	# Filesystems with coarse time precision may create timestamps
55	# equal to the one from a file that was very recently built and that
56	# needs to be rebuild. Let's guard against that by making sure our
57	# dep files are always newer than the first file we created here.
58	while [ ! "$depfile" -nt "$new_ksyms_file" ]; do
59		touch "$depfile"
60	done
61	echo $((count += 1))
62done | tail -1 )
63changed=${changed:-0}
64
65if [ $changed -gt 0 ]; then
66	# Replace the old list with tne new one
67	old=$(grep -c "^#define __KSYM_" "$cur_ksyms_file" || true)
68	new=$(grep -c "^#define __KSYM_" "$new_ksyms_file" || true)
69	info "KSYMS" "symbols: before=$old, after=$new, changed=$changed"
70	info "UPD" "$cur_ksyms_file"
71	mv -f "$new_ksyms_file" "$cur_ksyms_file"
72	# Then trigger a rebuild of affected source files
73	exec $@
74else
75	rm -f "$new_ksyms_file"
76fi
77