X-Git-Url: https://iankelling.org/git/?p=log-quiet;a=blobdiff_plain;f=log-once;h=5980b811423413ed01a33222112313b42b73ae94;hp=3aa3c766642b531f812d4d8d08486079497d936a;hb=HEAD;hpb=0913504bf944ba89714f898cd45a4c85b4781bce diff --git a/log-once b/log-once index 3aa3c76..8cfe388 100755 --- a/log-once +++ b/log-once @@ -1,12 +1,48 @@ #!/bin/bash +# I, Ian Kelling, follow the GNU license recommendations at +# https://www.gnu.org/licenses/license-recommendations.en.html. They +# recommend that small programs, < 300 lines, be licensed under the +# Apache License 2.0. This file contains or is part of one or more small +# programs. If a small program grows beyond 300 lines, I plan to switch +# its license to GPL. + +# Copyright 2024 Ian Kelling + +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at + +# http://www.apache.org/licenses/LICENSE-2.0 + +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. + # Copyright (C) 2019 Ian Kelling -# SPDX-License-Identifier: AGPL-3.0-or-later +# Log errors once or so instead of many times. + + # 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 3 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 . + +# SPDX-License-Identifier: GPL-3.0-or-later append() { cat >> "$1" } log-once() { - local cbase c log line i out file o tmp + local cbase c log line i out file o tmp mvout mverr verbose cbase=/var/local/cron-errors [[ $EUID == 0 ]] || cbase=$HOME/cron-errors local help="Usage: some-command-that-outputs-on-error |& log-once [OPTION]... LOG_NAME @@ -20,6 +56,7 @@ Logs STDIN to /var/local/cron-errors/LOG_NAME\$error_count or $HOME/cron-errors if not root, and keeps state in the same directory. -ERRORS: ERRORS is the number of errors to accumulate before outputing the error +-v: Output the errors along the way to ERRORS You can emulate how cronjobs work by doing this for example: @@ -30,10 +67,16 @@ I could imagine a similar command that considers its non-option args to be an error, but I haven't written it yet. " errors=3 + mverr=0 + verbose=false + while true; do if [[ $1 == --help ]]; then echo "$help" return + elif [[ $1 == -v ]]; then + verbose=true + shift elif [[ $1 == -[0-9]* ]]; then errors=${1#-} shift @@ -69,9 +112,19 @@ be an error, but I haven't written it yet. i="${file#$c}" if (( i < errors )); then new_file=$c$((i+1)) - mv $file $new_file + mvout=$(mv $file $new_file 2>&1) || mverr=$? + if (( mverr )); then + if [[ $mvout == *": No such file or directory" ]]; then + # We've very likely hit a race condition, where another + # log-once did the mv before us. + return 0 + else + echo "log-once: error on mv $file $new_file" + return $mverr + fi + fi file=$new_file - if [[ $file == $c$errors ]]; then + if [[ $file == $c$errors ]] || $verbose; then out="tee -a" fi fi