scripts/adjust_autoksyms.sh

   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
  17 set -e
  18
  19 cur_ksyms_file="include/generated/autoksyms.h"
  20 new_ksyms_file="include/generated/autoksyms.h.tmpnew"
  21
  22 info() {
  23         if [ "$quiet" != "silent_" ]; then
  24                 printf "  %-7s %s\n" "$1" "$2"
  25         fi
  26 }
  27
  28 info "CHK" "$cur_ksyms_file"
  29
  30 # Use "make V=1" to debug this script.
  31 case "$KBUILD_VERBOSE" in
  32 *1*)
  33         set -x
  34         ;;
  35 esac
  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.
  45 changed=$(
  46 count=0
  47 sort "$cur_ksyms_file" "$new_ksyms_file" | uniq -u |
  48 sed -n 's/^#define __KSYM_\(.*\) 1/\1/p' | tr "A-Z_" "a-z/" |
  49 while 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 $((count += 1))
  62 done | tail -1 )
  63 changed=${changed:-0}
  64
  65 if [ $changed -gt 0 ]; then
  66         # Replace the old list with tne new one
  67         old=$(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 $@
  74 else
  75         rm -f "$new_ksyms_file"
  76 fi