efrecon · June 5, 2019 21:57 · Jun 5, 2019 · Jun 4, 2019 · Jun 4, 2019 · Jun 4, 2019
diff --git a/cleaner.md b/cleaner.md
@@ -6,11 +6,10 @@ pattern. It should be scheduled on a regular basis from the outside, e.g. with
 
 ## Options
 
-`cleaner.sh` takes a number of single or double-dashed options, followed with
-the patterns/files to clean from. It is possible to separate the list of options
-from the destinations using a single double-dash, to mark the definitive end of
-the options. This enables to point at paths which would start with a dash sign
-(unlikely!).
+`cleaner.sh` takes a number of single or double-dashed options, possibly
+followed by a command to execute once the removal operations have ended. It is
+preferrable to separate the list of options from the command using a
+double-dash, to mark the definitive end of the options. 
 
 The following options are recognised.
 
@@ -19,10 +18,10 @@ The following options are recognised.
 The value of this option should be the number of files to keep. It defaults to
 an empty string, which is understood as keeping all the files.
 
-### `-t` or `--then`
+### `-f` or `--files`
 
-The value of this option is a command that will be evaluated once the removal
-operations have ended. It defaults to an empty string.
+The value of this option is (usually) a glob-style pattern to point at the list
+of files to select from when removing the oldest ones.
 
 ### `-v` or `--verbose`
 

diff --git a/cleaner.sh b/cleaner.sh
@@ -10,8 +10,8 @@
 
 # All (good?) defaults
 VERBOSE=0
-KEEP=""
-THEN=""
+KEEP=
+PATHS=
 
 # Dynamic vars
 cmdname=$(basename $(readlink -f $0))
@@ -28,14 +28,14 @@ Description:
   finite amount of the youngest files
 
 Usage:
-  $cmdname [-option arg --long-option(=)arg] pattern
+  $cmdname [-option arg --long-option(=)arg] ([--] command)
 
   where all dash-led options are as follows (long options can be followed by
   an equal sign):
     -v | --verbose       Be more verbose
     -k | --keep          Number of files to keep, defaults to empty,
                          meaning all
-    -t | --then          Command to execute once done
+    -f | --files         List of files to select from for removal
 USAGE
   exit "$exitcode"
 }
@@ -49,10 +49,10 @@ while [ $# -gt 0 ]; do
         --keep=*)
             KEEP="${1#*=}"; shift 1;;
 
-        -t | --then)
-            THEN=$2; shift 2;;
-        --then=*)
-            THEN="${1#*=}"; shift 1;;
+        -f | --files)
+            PATHS=$2; shift 2;;
+        --files=*)
+            PATHS="${1#*=}"; shift 1;;
 
         -v | --verbose)
             VERBOSE=1; shift;;
@@ -68,28 +68,28 @@ while [ $# -gt 0 ]; do
     esac
 done
 
-if [ $# -eq 0 ]; then
-    echo "You need to specify sources to copy for offline backup" >& 2
+if [ -z "$PATHS" ]; then
+    echo "You need to specify files to select from for removal" >& 2
     usage 1
 fi
 
 # Conditional logging
 log() {
-    if [ "$VERBOSE" == "1" ]; then
+    if [ "$VERBOSE" = "1" ]; then
         echo "$1"
     fi
 }
 
 if [ -n "${KEEP}" -a "${KEEP}" -gt "0" ]; then
-    log "Keeping only ${KEEP} youngest file(s) of $@"
-    while [ "$(ls $@ -1 -t | wc -l)" -gt "$KEEP" ]; do
-        DELETE=$(ls $@ -1 -t | sort -r | tail -n 1)
+    log "Keeping only ${KEEP} youngest file(s) of $PATHS"
+    while [ "$(ls $PATHS -1 -t | wc -l)" -gt "$KEEP" ]; do
+        DELETE=$(ls $PATHS -1 -t | sort -r | tail -n 1)
         log "Removing old copy $DELETE"
         rm -rf $DELETE
     done
 fi
 
-if [ -n "${THEN}" ]; then
-    log "Executing ${THEN}"
-    eval "${THEN}"
+if [ $# -ne "0" ]; then
+    log "Executing $*"
+    exec "$@"
 fi
diff --git a/cleaner.sh b/cleaner.sh
diff --git a/cleaner.md b/cleaner.md
@@ -0,0 +1,35 @@
+# Cleaner for Backups
+
+`cleaner.sh` is a script to keep a finite number of backup (files) matching a
+pattern. It should be scheduled on a regular basis from the outside, e.g. with
+`cron`.
+
+## Options
+
+`cleaner.sh` takes a number of single or double-dashed options, followed with
+the patterns/files to clean from. It is possible to separate the list of options
+from the destinations using a single double-dash, to mark the definitive end of
+the options. This enables to point at paths which would start with a dash sign
+(unlikely!).
+
+The following options are recognised.
+
+### `-k` or `--keep`
+
+The value of this option should be the number of files to keep. It defaults to
+an empty string, which is understood as keeping all the files.
+
+### `-t` or `--then`
+
+The value of this option is a command that will be evaluated once the removal
+operations have ended. It defaults to an empty string.
+
+### `-v` or `--verbose`
+
+When this option is given, verbosity will be increased.
+
+## Notes
+
+This utility is tuned for maximal compatibility. It only requires a basic POSIX
+shell.  As a result, `cleaner.sh` can easilty be used from containers or in
+embedded systems.
diff --git a/LICENSE b/LICENSE
@@ -0,0 +1,29 @@
+BSD 3-Clause License
+
+Copyright (c) 2019, Emmanuel Frecon <efrecon@gmail.com>
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+* Redistributions of source code must retain the above copyright notice, this
+  list of conditions and the following disclaimer.
+
+* Redistributions in binary form must reproduce the above copyright notice,
+  this list of conditions and the following disclaimer in the documentation
+  and/or other materials provided with the distribution.
+
+* Neither the name of the copyright holder nor the names of its
+  contributors may be used to endorse or promote products derived from
+  this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
diff --git a/cleaner.sh b/cleaner.sh
@@ -0,0 +1,95 @@
+#!/bin/sh
+
+# TODO:
+# add a --uploads option to specify the number of latest files to uploads. Good
+# in case we missed some.
+# add options to wait before starting, similar to mirror.tcl
+# add option to sleep and restart automatically
+
+#set -x
+
+# All (good?) defaults
+VERBOSE=0
+KEEP=""
+THEN=""
+
+# Dynamic vars
+cmdname=$(basename $(readlink -f $0))
+appname=${cmdname%.*}
+
+# Print usage on stderr and exit
+usage() {
+  exitcode="$1"
+  cat << USAGE >&2
+  
+Description:
+
+  $cmdname will find the latest files matching a pattern and only keep a
+  finite amount of the youngest files
+
+Usage:
+  $cmdname [-option arg --long-option(=)arg] pattern
+
+  where all dash-led options are as follows (long options can be followed by
+  an equal sign):
+    -v | --verbose       Be more verbose
+    -k | --keep          Number of files to keep, defaults to empty,
+                         meaning all
+    -t | --then          Command to execute once done
+USAGE
+  exit "$exitcode"
+}
+
+
+# Parse options
+while [ $# -gt 0 ]; do
+    case "$1" in
+        -k | --keep)
+            KEEP=$2; shift 2;;
+        --keep=*)
+            KEEP="${1#*=}"; shift 1;;
+
+        -t | --then)
+            THEN=$2; shift 2;;
+        --then=*)
+            THEN="${1#*=}"; shift 1;;
+
+        -v | --verbose)
+            VERBOSE=1; shift;;
+
+        -h | --help)
+            usage 0;; 
+        --)
+            shift; break;;
+        -*)
+            echo "Unknown option: $1 !" >&2 ; usage 1;;
+        *)
+            break;;
+    esac
+done
+
+if [ $# -eq 0 ]; then
+    echo "You need to specify sources to copy for offline backup" >& 2
+    usage 1
+fi
+
+# Conditional logging
+log() {
+    if [ "$VERBOSE" == "1" ]; then
+        echo "$1"
+    fi
+}
+
+if [ -n "${KEEP}" -a "${KEEP}" -gt "0" ]; then
+    log "Keeping only ${KEEP} youngest file(s) of $@"
+    while [ "$(ls $@ -1 -t | wc -l)" -gt "$KEEP" ]; do
+        DELETE=$(ls $@ -1 -t | sort -r | tail -n 1)
+        log "Removing old copy $DELETE"
+        rm -rf $DELETE
+    done
+fi
+
+if [ -n "${THEN}" ]; then
+    log "Executing ${THEN}"
+    eval "${THEN}"
+fi