recipes-bsp/gbmc-bsp-common/files/gbmc-trim-kconfig.sh

#!/bin/bash
# Parses Kconfig lines like
#   CONFIG_DEBUG=y >=6.1
#   # CONFIG_DEBUG is not set <6.1
# and only adds them to the build if the kernel is 6.1 or greater
# Regular lines are unchanged
version="$1"
shift
declare -A plats
for plat in $1; do
  plats["$plat"]=1
done
shift
files=("$@")
# Disallow "x.y" versions as they don't sort correctly
is_xy_ver() {
  [[ "$1" =~ ^[0-9]+[.][0-9]+$ ]]
}
if is_xy_ver "$version"; then
  echo "Linux version is unsupported $version" >&2
  exit 1
fi
declare -A config=()
fail=
for file in "${files[@]}"; do
  echo "Trimming $file to $version" >&2
  fdone=0
  while (( fdone == 0 )); do
    read -r line || fdone=$?
    if [[ $line =~ ^'# '(CONFIG_[_A-Za-z0-9]*)' is not set'( (.*))?$ ]]; then
      # Match options that unset configuration options equivalent to CONFIG_*=n
      #  - # CONFIG_I2C_MUX_PCA9541 is not set
      #  - # CONFIG_DEVPORT is not set
      key="${BASH_REMATCH[1]}"
      op='='
      val='n'
      larr=(${BASH_REMATCH[3]})
    elif [[ $line =~ ^(CONFIG_[_A-Za-z0-9]*)(=|'+=')('"'.*'"'|[^ ]*)(' '(.*))? ]]; then
      # Match options that set configuration options equivalent to CONFIG_*=<val>
      #  - CONFIG_I2C_MUX_PCA954x=y
      #  - CONFIG_DEVMEM=y armv7,armv8
      #
      # Also match append operations (can only be used on strings)
      #  - CONFIG_CMDLINE+=" opt1"
      #  - CONFIG_CMDLINE+=" opt2" armv8
      key="${BASH_REMATCH[1]}"
      op="${BASH_REMATCH[2]}"
      val="${BASH_REMATCH[3]}"
      larr=(${BASH_REMATCH[5]})
    elif [[ $line =~ ^' '*(#.*)?$ ]]; then
      continue
    else
      echo "Unrecognized line: $line" >&2
      fail=1
    fi
    skip=
    for const in "${larr[@]}"; do
      if [[ "${const:0:1}" == '#' ]]; then
        break
      elif [[ ${const:0:2} == '>=' ]]; then
        if is_xy_ver "${const:2}"; then
          echo "Constraint version is unsupported ${const:2}: $line" >&2
          fail=1
        fi
        expected="${const:2}"$'\n'"$version"
        if [[ $expected != $(echo "$expected" | sort -V) ]]; then
          skip=1
          break
        fi
      elif [[ ${const:0:1} == '>' ]]; then
        if is_xy_ver "${const:1}"; then
          echo "Constraint version is unsupported ${const:1}: $line" >&2
          fail=1
        fi
        expected="${const:1}"$'\n'"$version"
        if [[ ${const:1} == $version || $expected != $(echo "$expected" | sort -V) ]]; then
          skip=1
          break
        fi
      elif [[ ${const:0:2} == '<=' ]]; then
        if is_xy_ver "${const:2}"; then
          echo "Constraint version is unsupported ${const:2}: $line" >&2
          fail=1
        fi
        expected="$version"$'\n'"${const:2}"
        if [[ $expected != $(echo "$expected" | sort -V) ]]; then
          skip=1
          break
        fi
      elif [[ ${const:0:1} == '<' ]]; then
        if is_xy_ver "${const:1}"; then
          echo "Constraint version is unsupported ${const:1}: $line" >&2
          fail=1
        fi
        expected="$version"$'\n'"${const:1}"
        if [[ ${const:1} == $version || $expected != $(echo "$expected" | sort -V) ]]; then
          skip=1
          break
        fi
      elif [[ $const =~ ^[a-zA-Z0-9] ]]; then
        OLDIFS="$IFS"
        IFS=','
        match=
        for plat in $const; do
          if [[ -v plats["$plat"] ]]; then
            match=1
            break
          fi
        done
        IFS="$OLDIFS"
        if [[ -z "$match" ]]; then
          skip=1
          break
        fi
      else
        echo "Unexpected constraint '$const' at line: $line" >&2
        fail=1
      fi
    done
    if [[ -z $skip ]]; then
      if [[ $op == '=' ]]; then
        config["$key"]="$val"
      elif [[ $op == '+=' ]]; then
        if [[ ${val:0:1} != '"' || "${val: -1}" != '"' ]]; then
          echo "Only know how to append strings: $line"
          fail=1
        fi
        oldval="${config["$key"]}"
        if [[ -z "$oldval" ]]; then
          config["$key"]="$val"
        else
          config["$key"]="${oldval:0:-1}${val:1}"
        fi
      else
        echo "Unrecognized operator '$op': $line" >&2
      fi
    fi
  done <"$file"
done
if [[ -n "$fail" ]]; then
  exit 1
fi
written=
for file in "${files[@]}"; do
  exec {nfile}<>"$file.tmp"
  # Only write to the first file in the list of files, so that our merged
  # values definitely only take effect once. We leave empty tombstones for
  # the old files, so that any build structure depending on them still works.
  if [[ -z "$written" ]]; then
    echo "Writing fuill config to $file" >&2
    for key in "${!config[@]}"; do
      echo "$key=${config["$key"]}" >&$nfile
    done
    written=1
  fi
  exec {nfile}>&-
  mv "$file.tmp" "$file"
done