diff options
author | davidovski <david@davidovski.xyz> | 2022-03-14 00:14:26 +0000 |
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committer | davidovski <david@davidovski.xyz> | 2022-03-14 00:14:26 +0000 |
commit | dffbbe56d3f9f17da0244f75b352b87bc0e244df (patch) | |
tree | f9472179419c592a4fd42048270da0913f5e6024 /udev/rule_generator.functions | |
parent | bfdef0f304e13766423aaabd1022c888e3193ff6 (diff) |
added udev
Diffstat (limited to 'udev/rule_generator.functions')
-rw-r--r-- | udev/rule_generator.functions | 115 |
1 files changed, 115 insertions, 0 deletions
diff --git a/udev/rule_generator.functions b/udev/rule_generator.functions new file mode 100644 index 0000000..7b8521f --- /dev/null +++ b/udev/rule_generator.functions @@ -0,0 +1,115 @@ +# functions used by the udev rule generator + +# Copyright (C) 2006 Marco d'Itri <md@Linux.IT> +# Updated for LFS by Bruce Dubbs <bdubbs@linuxfromscratch.org> +# Hardcoded RUNDIR + +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation, either version 2 of the License, or +# (at your option) any later version. + +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. + +# You should have received a copy of the GNU General Public License +# along with this program. If not, see <http://www.gnu.org/licenses/>. + +PATH='/usr/bin:/bin:/usr/sbin:/sbin' + +# Read a single line from file $1 in the $DEVPATH directory. +# The function must not return an error even if the file does not exist. +sysread() { + local file="$1" + [ -e "/sys$DEVPATH/$file" ] || return 0 + local value + read value < "/sys$DEVPATH/$file" || return 0 + echo "$value" +} + +sysreadlink() { + local file="$1" + [ -e "/sys$DEVPATH/$file" ] || return 0 + readlink -f /sys$DEVPATH/$file 2> /dev/null || true +} + +# Return true if a directory is writeable. +writeable() { + if ln -s test-link $1/.is-writeable 2> /dev/null; then + rm -f $1/.is-writeable + return 0 + else + return 1 + fi +} + +# Create a lock file for the current rules file. +lock_rules_file() { + RUNDIR=/run/udev + [ -e "$RUNDIR" ] || return 0 + + RULES_LOCK="$RUNDIR/.lock-${RULES_FILE##*/}" + + retry=30 + while ! mkdir $RULES_LOCK 2> /dev/null; do + if [ $retry -eq 0 ]; then + echo "Cannot lock $RULES_FILE!" >&2 + exit 2 + fi + sleep 1 + retry=$(($retry - 1)) + done +} + +unlock_rules_file() { + [ "$RULES_LOCK" ] || return 0 + rmdir $RULES_LOCK || true +} + +# Choose the real rules file if it is writeable or a temporary file if not. +# Both files should be checked later when looking for existing rules. +choose_rules_file() { + RUNDIR=/run/udev + local tmp_rules_file="$RUNDIR/tmp-rules--${RULES_FILE##*/}" + [ -e "$RULES_FILE" -o -e "$tmp_rules_file" ] || PRINT_HEADER=1 + + if writeable ${RULES_FILE%/*}; then + RO_RULES_FILE='/dev/null' + else + RO_RULES_FILE=$RULES_FILE + RULES_FILE=$tmp_rules_file + fi +} + +# Return the name of the first free device. +raw_find_next_available() { + local links="$1" + + local basename=${links%%[ 0-9]*} + local max=-1 + for name in $links; do + local num=${name#$basename} + [ "$num" ] || num=0 + [ $num -gt $max ] && max=$num + done + + local max=$(($max + 1)) + # "name0" actually is just "name" + [ $max -eq 0 ] && return + echo "$max" +} + +# Find all rules matching a key (with action) and a pattern. +find_all_rules() { + local key="$1" + local linkre="$2" + local match="$3" + + local search='.*[[:space:],]'"$key"'"('"$linkre"')".*' + echo $(sed -n -r -e 's/^#.*//' -e "${match}s/${search}/\1/p" \ + $RO_RULES_FILE \ + $([ -e $RULES_FILE ] && echo $RULES_FILE) \ + 2>/dev/null) +} |