Merge branch 'master' into wip-MvnDepScan-20221207

29 files changed, 476 insertions, 134 deletions

diff --git a/LICENSE.txt b/LICENSE.txt
new file mode 100644
index 0000000..b9e20aa
--- /dev/null
+++ b/LICENSE.txt
@@ -0,0 +1,14 @@
+

+Copyright (c) 2022 Andreas Fankhauser

+

+The above copyright notice and this permission notice shall be included in all

+copies or substantial portions of the Software.

+

+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE

+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE

+SOFTWARE.

+

diff --git a/doc/note/cross-compile/CrossCompile.txt b/doc/note/cross-compile/CrossCompile.txt
new file mode 100644
index 0000000..5341164
--- /dev/null
+++ b/doc/note/cross-compile/CrossCompile.txt
@@ -0,0 +1,8 @@
+
+Cross Compilation & Portability
+===============================
+
+10 most essential rules for portable C code:
+
+  https://www.ski-epic.com/source_code_essays/ten_rules_for_writing_cross_platform_c_source_code.html
+
diff --git a/doc/note/docker/Docker.txt b/doc/note/docker/Docker.txt
index 7a9d130..ac283c9 100644
--- a/doc/note/docker/Docker.txt
+++ b/doc/note/docker/Docker.txt
@@ -57,6 +57,17 @@ Side-Mount tcpdump into container where it does not exist
   docker run --rm -ti --network container:"${CNTNR_TO_DUMP:?}" -v "/tmp/foo:/work" "${IMG_WITH_TCPDUMP_EG_BASEIMG:?}" bash
 
 
+## Inspect failing docker-build
+
+See "https://stackoverflow.com/a/26222636/4415884"
+
+  docker run --rm -ti 42424242 sh
+
+HINT: Use the line which looks like:
+"---> 42424242"
+and NOT the one like:
+"---> Running in 42424242"
+
 
 ## Publish custom images to artifactory
 
diff --git a/doc/note/ffmpeg/ffmpeg.txt b/doc/note/ffmpeg/ffmpeg.txt
index 9d95bfd..057c11d 100644
--- a/doc/note/ffmpeg/ffmpeg.txt
+++ b/doc/note/ffmpeg/ffmpeg.txt
@@ -2,7 +2,6 @@
 ffmpeg
 ================
 
-j
 ## Extract Audio From webm
 
 Lookup format of audio stream with:
@@ -17,9 +16,21 @@ Then use that knowlege to extract that (audio) stream:
 
 ## Convert Formats
 
-ffmpeg -i in.opus out.wav
+  ffmpeg -i in.opus out.wav
 
 
+## Fine-tune audio codec
+
+[See also](https://slhck.info/video/2017/02/24/vbr-settings.html)
+
+Use  -codec:v copy  to keep video, or -codec:v no  for audio-only.
+
+  -codec:a aac        -q:a 1.3   (min=0.1, good=1.3 max=2)
+  -codec:a aac        -b:a 96k
+  -codec:a libmp3lame -q:a 2
+  -codec:a libopus
+  -filter:a lowpass=f=16000
+
 
 ## Record Desktop
 
diff --git a/doc/note/gpg/gpg.txt b/doc/note/gpg/gpg.txt
new file mode 100644
index 0000000..015887c
--- /dev/null
+++ b/doc/note/gpg/gpg.txt
@@ -0,0 +1,82 @@
+
+How to GnuPG
+============
+
+WARN: You MUST only use those instructions if you know exactly what
+you're doing! If you don't, you MUST NOT use those instructions!
+
+
+## Prepare for a master key creation
+
+- Choose a storage medium which will keep the master key and will be
+  kept VERY SAVE somewhere (also think for some redundancy). WARN: If
+  you choose a medium which probably could fail, you will be screwed up
+  in a later point in time!
+- Choose how (or where?) to keep master passphrase.
+
+
+## Initialize a new master key
+
+  export GNUPGHOME=/mnt/your/master/.gnupg
+  gpg --full-gen-key
+
+
+## Add additional identities (as needed)
+
+  export GNUPGHOME=/mnt/your/master/.gnupg
+  gpg --edit-key foo@example.com
+  gpg> adduid
+  gpg> save
+
+
+## Create keys for some daily-use devices
+
+  export GNUPGHOME=/mnt/your/master/.gnupg
+  gpg --edit-key foo@example.com
+  # Add an encryption and a sign key
+  gpg> addkey    (then choose "encryp only")
+  gpg> addkey    (then choose "sign only")
+
+
+## Export subkeys for use on a daily-use device
+
+  # From now work with a temporary copy.
+  mkdir /mnt/your/tmp/.gnupg
+  (cd /mnt/your/master/.gnupg && tar c $(ls -A)) | (cd /mnt/your/tmp/.gnupg && tar x)
+  export GNUPGHOME=/mnt/your/tmp/.gnupg
+  # Print list of what we have
+  gpg --edit-key foo@example.com quit
+  # I suggest to use a different passphrase than the master key has.
+  # (HINT: just ignore error about missing private key. it works anyway)
+  gpg --edit-key foo@example.com passwd quit
+  # For each device choose one encrypt and one sign key and replace F00 and BA5
+  # below with them.
+  gpg --export-secret-subkeys F00! BA5! > keys-for-device
+
+
+## Import prepared subkeys on daily-use device
+
+  gpg --import keys-for-device
+  gpg --edit-key foo@example.com
+  gpg> trust
+  gpg> save
+
+
+## Sign a foreign key to express to the world that we trust it
+
+  gpgwin --sign-key foreignUser@example.com
+
+
+## Some other helpful places
+
+- "https://insight.o-o.studio/article/setting-up-gpg.html#encryption-key"
+- "https://davesteele.github.io/gpg/2014/09/20/anatomy-of-a-gpg-key/"
+- "https://gpg.wtf/"
+
+
+## Start/stop gpg-agent
+
+  gpgconf --kill gpg-agent
+  gpgconf --launch gpg-agent
+
+
diff --git a/doc/note/links/links.txt b/doc/note/links/links.txt
index 3ca26ba..af41581 100644
--- a/doc/note/links/links.txt
+++ b/doc/note/links/links.txt
@@ -1,5 +1,5 @@
 
-Links (Aka arguments)
+Links (Aka argument amplifiers)
 =====================
 
 ## Pro DI over serviceLocator
@@ -82,7 +82,7 @@ Links (Aka arguments)
 - SRP "https://blog.ndepend.com/solid-design-the-single-responsibility-principle-srp/"
 - OCP "https://blog.ndepend.com/solid-design-the-open-close-principle-ocp/"
 - LSP "https://blog.ndepend.com/solid-design-the-liskov-substitution-principle/"
-- DIP "https://stackify.com/dependency-inversion-principle/"
+- DIP "https://stackify.com/dependency-inversion-principle/#post-18184-_nuqaxpnmvpn7"
 
 ## Java how to handle InterruptedException:
 - "https://www.yegor256.com/2015/10/20/interrupted-exception.html"
@@ -121,7 +121,7 @@ Links (Aka arguments)
 ## Why I Have Given Up On Coding Standards
 - "http://www.richardrodger.com/2012/11/03/why-i-have-given-up-on-coding-standards/"
 
-## slf4j logger dos and donts0
+## slf4j logger dos and donts
 - [case SO](https://stackoverflow.com/questions/1417190/should-a-static-final-logger-be-declared-in-upper-case)
 - [case java-styleguide](https://web.archive.org/web/20120911192801if_/http://developers.sun.com/sunstudio/products/archive/whitepapers/java-style.pdf#G3.5426)
 - [case slf4j](http://www.slf4j.org/api/org/slf4j/Logger.html)
@@ -148,10 +148,13 @@ Links (Aka arguments)
 - "https://gitit.post.ch/projects/ISA/repos/zarquon/pull-requests/2/overview?commentId=61312"
 
 ## Code Style format auto-formatters
+- [warning about formatters](https://gitit.post.ch/projects/ISA/repos/trin/pull-requests/79/overview?commentId=235667)
 - [static final java uppercase](https://gitit.post.ch/projects/ISA/repos/preflux/pull-requests/82/overview?commentId=39126)
 - [invalid java class name](https://gitit.post.ch/projects/ISA/repos/preflux/pull-requests/82/overview?commentId=39125)
-- [Formatters produce crap](https://gitit.post.ch/projects/ISA/repos/minetti/pull-requests/14/overview)
-- [Formatters produce crap](https://gitit.post.ch/projects/ISA/repos/veet/pull-requests/2/overview?commentId=233638)
+- [Spotless produces crap](https://gitit.post.ch/projects/ISA/repos/minetti/pull-requests/14/overview)
+- [Spotless produces crap](https://gitit.post.ch/projects/ISA/repos/veet/pull-requests/2/overview?commentId=233638)
+- [Spotless produces crap](https://gitit.post.ch/projects/ISA/repos/trin/pull-requests/79)
+- [Linter produces crap](https://gitit.post.ch/projects/ISA/repos/preflux/pull-requests/567/overview?commentId=237627)
 - [Suddenly NEW formatting rules in PaISA since 2021](https://gitit.post.ch/projects/ISA/repos/watson/pull-requests/1/overview?commentId=234597)
 - "https://gitit.post.ch/projects/ISA/repos/zarniwoop/pull-requests/20/overview?commentId=85912"
 - "https://gitit.post.ch/projects/ISA/repos/zarniwoop/pull-requests/21/overview?commentId=87250"
@@ -299,6 +302,7 @@ Links (Aka arguments)
 
 ## Command Escaping And Injection
 - "https://jira.post.ch/browse/SDCISA-3602"
+- [My hopefully bullet-proove shell escaping](https://gitit.post.ch/projects/ISA/repos/jenkins-shared-libraries/pull-requests/82/overview?commentId=237165)
 
 ## logger noise spam verbose
 - [fix the REAL problem please](https://jira.post.ch/browse/SDCISA-3637?focusedCommentId=1252741&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-1252741)
@@ -310,6 +314,7 @@ Links (Aka arguments)
 
 ## YAGNI (but also KISS and DRY)
 - "https://medium.com/swlh/yagni-and-dry-the-kiss-of-death-for-your-software-project-cfd44b0654b6#fc82"
+- [eagle queue json only](https://gitit.post.ch/projects/ISA/repos/eagle/pull-requests/331/overview?commentId=236944)
 
 ## How to format method parameters
 - "https://gitit.post.ch/projects/ISA/repos/god-backend/pull-requests/281/overview?commentId=210650"
@@ -409,3 +414,21 @@ Links (Aka arguments)
 ## Encoding mime application/octet-stream string utf8 unicode json payload data
 - [eagle queue browser](https://gitit.post.ch/projects/ISA/repos/eagle/pull-requests/331/overview?commentId=232322)
 
+## Stop using that stupid mouse! For some reason you've got a keyboard
+- [_](https://www.vice.com/en/article/d3m8ga/i-stopped-using-a-computer-mouse-for-a-week)
+- [_](https://medium.com/ae-studio/save-a-month-of-your-life-by-using-these-keyboard-shortcuts-a07fdba5dc6e)
+- [_](https://blog.superhuman.com/keyboard-vs-mouse/)
+
+## How to get real InputStream from RestTemplate
+- [java spring http web InputStream RestTemplate body](https://stackoverflow.com/a/62649586/4415884)
+
+## Stone age deprecated obsolete for years
+- [API using naming deprecated for 7 years](https://gitit.post.ch/projects/ISA/repos/notifications-api/pull-requests/7/overview?commentId=238160)
+
+## ImageMagic
+- [Bulk resize pictures](https://stackoverflow.com/questions/36986436/how-to-batch-resize-millions-of-images-to-fit-a-max-width-and-height)
+- [mogrify bulk changes](https://www.lostsaloon.com/technology/resize-multiple-images-batch-command-line-linux/)
+
+## Windoof
+- [Enable w32 crashdump](https://learn.microsoft.com/en-us/windows/win32/wer/collecting-user-mode-dumps?source=recommendations)
+
diff --git a/doc/note/maven-pom/base.xml b/doc/note/maven-pom/base.xml
new file mode 100644
index 0000000..68624fb
--- /dev/null
+++ b/doc/note/maven-pom/base.xml
@@ -0,0 +1,34 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+     xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
+
+  <modelVersion>4.0.0</modelVersion>
+
+  <groupId>TODO</groupId>
+  <artifactId>TODO</artifactId>
+  <version>0.0.0-SNAPSHOT</version>
+
+  <!-- <parent> -->
+  <!--   <groupId>TODO</groupId> -->
+  <!--   <artifactId>TODO</artifactId> -->
+  <!--   <version>TODO</version> -->
+  <!-- </parent> -->
+
+  <!-- <packaging>Choose: jar, pom, war</packaging> -->
+
+  <!-- <properties> -->
+  <!--   <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> -->
+  <!--   <maven.compiler.source>8</maven.compiler.source> -->
+  <!--   <maven.compiler.target>8</maven.compiler.target> -->
+  <!-- </properties> -->
+
+  <!-- <dependencies> -->
+  <!-- </dependencies> -->
+
+  <!-- <dependencyManagement> -->
+  <!--   <dependencies> -->
+  <!--   </dependencies> -->
+  <!-- </dependencyManagement> -->
+
+</project>
diff --git a/doc/note/ssh/_SeeAlsoTls b/doc/note/ssh/_SeeAlsoTls
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/doc/note/ssh/_SeeAlsoTls
diff --git a/doc/note/tls/_SeeAlsoSsh b/doc/note/tls/_SeeAlsoSsh
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/doc/note/tls/_SeeAlsoSsh
diff --git a/doc/note/tls/tls.txt b/doc/note/tls/tls.txt
new file mode 100644
index 0000000..ce1e305
--- /dev/null
+++ b/doc/note/tls/tls.txt
@@ -0,0 +1,34 @@
+
+TLS Key Management
+==================
+
+WARN: Nothing useful here. Just some nonsense copy-pasta lines.
+
+
+## Create new server PEM cert
+
+```sh
+openssl genrsa -out path/to/private/key 2048
+```
+
+```sh
+openssl req -new -key path/to/private/key -new -nodes -x509 -days 42 -out path/to/certSignRequest.csr -subj "/C=/ST=/L=/O=/OU=/CN=example.com"
+```
+
+```sh
+openssl x509 -req -days 42 -in path/to/certSignRequest.csr -signkey path/to/private/key -out path/to/cert.crt
+```
+
+```sh
+cat path/to/private/key path/to/cert.crt > path/to/cert.pem
+```
+
+
+## TLS debugging
+
+```sh
+socat OPENSSL-LISTEN:1234,reuseaddr,cert=server.pem tcp-connect:127.0.0.1:1235
+```
+
+HINT: Add option 'fork' to ssl sock to serve multiple requests.
+
diff --git a/src/main/docker/windoof-gcc.Dockerfile b/src/main/docker/gcc-windoof.Dockerfile
index 69cc18e..69cc18e 100644
--- a/src/main/docker/windoof-gcc.Dockerfile
+++ b/src/main/docker/gcc-windoof.Dockerfile
diff --git a/src/main/docker/debian-gcc.Dockerfile b/src/main/docker/gcc.Dockerfile
index 5894667..5894667 100644
--- a/src/main/docker/debian-gcc.Dockerfile
+++ b/src/main/docker/gcc.Dockerfile
diff --git a/src/main/docker/debian-cxx.Dockerfile b/src/main/docker/gxx.Dockerfile
index f29f168..f29f168 100644
--- a/src/main/docker/debian-cxx.Dockerfile
+++ b/src/main/docker/gxx.Dockerfile
diff --git a/src/main/docker/debian-jni.Dockerfile b/src/main/docker/jni.Dockerfile
index c790e47..c790e47 100644
--- a/src/main/docker/debian-jni.Dockerfile
+++ b/src/main/docker/jni.Dockerfile
diff --git a/src/main/docker/alpine-jre8.Dockerfile b/src/main/docker/jre8.Dockerfile
index 603b5f5..603b5f5 100644
--- a/src/main/docker/alpine-jre8.Dockerfile
+++ b/src/main/docker/jre8.Dockerfile
diff --git a/src/main/docker/alpine-mvn.Dockerfile b/src/main/docker/maven.Dockerfile
index e6c68f9..c33d519 100644
--- a/src/main/docker/alpine-mvn.Dockerfile
+++ b/src/main/docker/maven.Dockerfile
@@ -1,12 +1,9 @@
 #
 # Maven build env.
 #
-# Make sure to use arg
+# Use this to share your hosts repository with the container:
 #
-#   -v "$HOME/.m2/repo:/data/maven/.m2/repo"
-#
-# so it can use your hosts artifacts cache. If you miss this, mvn has to
-# download all the dependencies from remote uselessly often.
+#   -v "$HOME/.m2/repository:/data/maven/.m2/repository"
 #
 
 ARG PARENT_IMAGE=alpine:3.16.0
@@ -24,7 +21,7 @@ WORKDIR /work
 RUN true \
     && $PKGINIT \
     && $PKGADD $PKGS_TO_ADD \
-    && sed -i "s,</settings>,  <localRepository>/data/maven/.m2/repo</localRepository>\n</settings>,g" /usr/share/java/maven-3/conf/settings.xml \
+    && sed -i "s,</settings>,  <localRepository>/data/maven/.m2/repository</localRepository>\n</settings>,g" /usr/share/java/maven-3/conf/settings.xml \
     && mkdir /data /data/maven \
     && chown 1000:1000 /data/maven \
     && chown 1000:1000 /work \
diff --git a/src/main/java/ch/hiddenalpha/unspecifiedgarbage/collection/CollectionUtils.java b/src/main/java/ch/hiddenalpha/unspecifiedgarbage/collection/CollectionUtils.java
index a75594f..415090f 100644
--- a/src/main/java/ch/hiddenalpha/unspecifiedgarbage/collection/CollectionUtils.java
+++ b/src/main/java/ch/hiddenalpha/unspecifiedgarbage/collection/CollectionUtils.java
@@ -13,9 +13,9 @@ public class CollectionUtils {
      * @param <T>
      *     Type of the elements we are working with.
      */
-    public static <T> boolean contains(T[] haystack, T needle, java.util.function.BiPredicate<T, T> equals) {
-        for (T t : haystack) {
-            if (equals.test(needle, t)) {
+    public static <T> boolean contains( T[] haystack, T needle, java.util.function.BiPredicate<T, T> equals ){
+        for( T t : haystack ){
+            if( equals.test(needle, t) ){
                 return true;
             }
         }
diff --git a/src/main/java/ch/hiddenalpha/unspecifiedgarbage/format/FormatUtils.java b/src/main/java/ch/hiddenalpha/unspecifiedgarbage/format/FormatUtils.java
index bd39e40..e156eb8 100644
--- a/src/main/java/ch/hiddenalpha/unspecifiedgarbage/format/FormatUtils.java
+++ b/src/main/java/ch/hiddenalpha/unspecifiedgarbage/format/FormatUtils.java
@@ -1,54 +1,6 @@
 package ch.hiddenalpha.unspecifiedgarbage.format;
 
 
-public class FormatUtils {
-
-    /**
-     * Tries to format 'val' as a small integer. If not possible falls back
-     * to decimal representation. If also not possible, falls back to scientific
-     * notation.
-     *
-     * Handy in cases where we need to "just print that number" without having
-     * stupid amount of nonsense decimal places or bother readers with
-     * scientific notation where "just an int" would perfectly do the job.
-     *
-     * @param val
-     *      The number to format.
-     *
-     * @param ndig
-     *      How many significant digits to be printed. MUST be in range 1..7.
-     */
-    public static String toStr(float val, int ndig) {
-        int exp;
-        float limit;
-        if (val == 0) return "0";
-        switch (ndig) {
-            case 1: exp = 1; limit = 1e4F; break;
-            case 2: exp = 10; limit = 1e6F; break;
-            case 3: exp = 100; limit = 1e7F; break;
-            case 4: exp = 1000; limit = 1e8F; break;
-            case 5: exp = 10000; limit = 1e9F; break;
-            case 6: exp = 100000; limit = 1e10F; break;
-            case 7: exp = 1000000; limit = 1e11F; break;
-            default: throw new IllegalArgumentException("ndig " + ndig + " not in expected range 1..7");
-        }
-        if (val >= exp && val <= limit) {
-            // Just print as an int.
-            return String.valueOf((int) val);
-        } else {
-            String fmt;
-            switch (ndig) { // Select an appropriate format.
-                case 1: fmt = "%.1g"; break;
-                case 2: fmt = "%.2g"; break;
-                case 3: fmt = "%.3g"; break;
-                case 4: fmt = "%.4g"; break;
-                case 5: fmt = "%.5g"; break;
-                case 6: fmt = "%.6g"; break;
-                case 7: fmt = "%.7g"; break;
-                default: throw new IllegalArgumentException("ndig " + ndig + " not in expected range 1..7");
-            }
-            return String.format(fmt, val).replace(',', '.').replace("'", "");
-        }
-    }
-
-}
+/** Obsolete: This class did migrate to "xtra4j" */
+@Deprecated
+public class FormatUtils {}
diff --git a/src/main/java/ch/hiddenalpha/unspecifiedgarbage/json/JsonUtils.java b/src/main/java/ch/hiddenalpha/unspecifiedgarbage/json/JsonUtils.java
index c8be86a..f860b85 100644
--- a/src/main/java/ch/hiddenalpha/unspecifiedgarbage/json/JsonUtils.java
+++ b/src/main/java/ch/hiddenalpha/unspecifiedgarbage/json/JsonUtils.java
@@ -24,18 +24,18 @@ public class JsonUtils {
      */
     public static
     <TreeToValueFunc extends ObjectCodecIface<JsonNode, Map>, JsonNode, K, V>
-    Map<K, V> decodeMap(TreeToValueFunc treeToValueFunc, JsonNode mapNode, Class<K> keyType, Class<V> valueType) throws IOException {
+    Map<K, V> decodeMap( TreeToValueFunc treeToValueFunc, JsonNode mapNode, Class<K> keyType, Class<V> valueType ) throws IOException {
         final Map<K, V> envVars;
-        if (mapNode == null) {
+        if( mapNode == null ){
             envVars = new LinkedHashMap<>();
-        } else {
+        }else{
             envVars = treeToValueFunc.treeToValue(mapNode, Map.class);
         }
         return envVars;
     }
 
     public static interface ObjectCodecIface<TreeNode, Value> {
-        Value treeToValue(TreeNode input, Class<Map> returnType) throws IOException;
+        Value treeToValue( TreeNode input, Class<Map> returnType ) throws IOException;
     }
 
 
diff --git a/src/main/java/ch/hiddenalpha/unspecifiedgarbage/octetstream/ByteChunkOStream.java b/src/main/java/ch/hiddenalpha/unspecifiedgarbage/octetstream/ByteChunkOStream.java
index 04688d6..49959fc 100644
--- a/src/main/java/ch/hiddenalpha/unspecifiedgarbage/octetstream/ByteChunkOStream.java
+++ b/src/main/java/ch/hiddenalpha/unspecifiedgarbage/octetstream/ByteChunkOStream.java
@@ -38,8 +38,8 @@ public class ByteChunkOStream extends OutputStream {
                 len -= appendedBytes;
             }else if( remainingBytes == 0 ){
                 break; // Done :)
-            }else {
-                throw new UnsupportedOperationException("Huh?!? why is remainingBytes " + remainingBytes + "?");
+            }else{
+                throw new UnsupportedOperationException("Huh?!? why is remainingBytes "+ remainingBytes +"?");
             }
         }
     }
@@ -117,11 +117,11 @@ public class ByteChunkOStream extends OutputStream {
 
     /** Inspired by {@link java.util.function.Consumer} */
     public static interface ChunkHandler {
-        void accept(byte[] bytes) throws IOException;
+        void accept( byte[] bytes ) throws IOException;
     }
 
 
-    /** Inspired by {@link Runnable#run()} */
+    /** Inspired by {@link java.util.function.Runnable#run()} */
     public static interface EndHandler {
         void run() throws IOException;
     }
diff --git a/src/main/java/ch/hiddenalpha/unspecifiedgarbage/octetstream/ByteCountOutputStream.java b/src/main/java/ch/hiddenalpha/unspecifiedgarbage/octetstream/ByteCountOutputStream.java
index 006ea6b..8e2b47f 100644
--- a/src/main/java/ch/hiddenalpha/unspecifiedgarbage/octetstream/ByteCountOutputStream.java
+++ b/src/main/java/ch/hiddenalpha/unspecifiedgarbage/octetstream/ByteCountOutputStream.java
@@ -31,13 +31,9 @@ public class ByteCountOutputStream extends OutputStream {
     }
 
     @Override
-    public void flush() throws IOException {
-        origin.flush();
-    }
+    public void flush() throws IOException { origin.flush(); }
 
     @Override
-    public void close() throws IOException {
-        origin.close();
-    }
+    public void close() throws IOException { origin.close(); }
 
 }
diff --git a/src/main/java/ch/hiddenalpha/unspecifiedgarbage/octetstream/BytePool.java b/src/main/java/ch/hiddenalpha/unspecifiedgarbage/octetstream/BytePool.java
index 4a619da..b6c8131 100644
--- a/src/main/java/ch/hiddenalpha/unspecifiedgarbage/octetstream/BytePool.java
+++ b/src/main/java/ch/hiddenalpha/unspecifiedgarbage/octetstream/BytePool.java
@@ -91,7 +91,7 @@ public class BytePool {
             long amountLong = oldVal - newVal;
             this.amount.set((int) amountLong);
             if( this.amount.get() != amountLong ){
-                throw new RuntimeException("A moron just tried to allocate " + amountLong + " bytes (more than INT_MAX)");
+                throw new RuntimeException("A moron just tried to allocate "+ amountLong +" bytes (more than INT_MAX)");
             }
         }
 
@@ -107,7 +107,7 @@ public class BytePool {
          *     // Don't know exactly how much we need. Make a guess.<br/>
          *     allocdBytes = pool.alloc(42);<br/>
          *     int actuallyNeeded = source.read(buf, 0, allocdBytes.getAmount());<br/>
-         *     // Now we know exactly how much we need and can free the rest.<br/>
+         *     // Now we know exactly how much we need and can release the rest.<br/>
          *     allocdBytes.shrinkTo(actuallyNeeded);<br/>
          * </code>
          */
diff --git a/src/main/java/ch/hiddenalpha/unspecifiedgarbage/octetstream/CRLFtoLFOutputStream.java b/src/main/java/ch/hiddenalpha/unspecifiedgarbage/octetstream/CRLFtoLFOutputStream.java
index 75b1a9f..0c242aa 100644
--- a/src/main/java/ch/hiddenalpha/unspecifiedgarbage/octetstream/CRLFtoLFOutputStream.java
+++ b/src/main/java/ch/hiddenalpha/unspecifiedgarbage/octetstream/CRLFtoLFOutputStream.java
@@ -4,13 +4,15 @@ import java.io.FilterOutputStream;
 import java.io.IOException;
 import java.io.OutputStream;
 
+import org.slf4j.ILoggerFactory;
+import org.slf4j.Logger;
 
-/**
- * Filter to fix broken newlines.
- */
+
+/** Filters away broken newlines. */
 public class CRLFtoLFOutputStream extends FilterOutputStream {
 
     private static final int EMPTY = -42;
+    private final Logger log;
     private int previous = EMPTY;
 
     /**
@@ -18,7 +20,16 @@ public class CRLFtoLFOutputStream extends FilterOutputStream {
      *      Destination where the result will be written to.
      */
     public CRLFtoLFOutputStream( OutputStream dst ) {
+        this(dst, null);
+    }
+
+    /**
+     * @param dst
+     *      Destination where the result will be written to.
+     */
+    public CRLFtoLFOutputStream( OutputStream dst, ILoggerFactory lf ) {
         super(dst);
+        this.log = (lf == null) ? null : lf.getLogger(CRLFtoLFOutputStream.class.getName());
     }
 
     @Override
@@ -27,7 +38,7 @@ public class CRLFtoLFOutputStream extends FilterOutputStream {
         // This allows us to assign special meanings to those values internally (eg our
         // 'EMPTY' value). For this to work, we clear the high bits to not get confused
         // just in case someone really passes such values.
-        current = current & 0xFF;
+        current &= 0xFF;
 
         if( previous == '\r' && current == '\n' ){
             // Ignore the CR and only write the LF.
@@ -43,14 +54,21 @@ public class CRLFtoLFOutputStream extends FilterOutputStream {
         }
     }
 
+    // TODO we should override this.
+    //@Override
+    //public void write( byte[] buf, int off, int len ) throws IOException {
+    //    throw new UnsupportedOperationException("TODO impl");/*TODO*/
+    //}
+
     @Override
     public void flush() throws IOException {
         if( previous == '\r' ){
-            //log.warn("Have to flush a CR byte without knowing if the next byte might be a LF");
+            log.debug("Have to flush a CR byte without knowing if the next byte might be a LF");
         }
         if( previous != EMPTY ){
-            super.write(previous);
+            int tmp = previous;
             previous = EMPTY;
+            super.write(tmp);
         }
         super.flush();
     }
diff --git a/src/main/java/ch/hiddenalpha/unspecifiedgarbage/octetstream/CloseNotifyOutputStream.java b/src/main/java/ch/hiddenalpha/unspecifiedgarbage/octetstream/CloseNotifyOutputStream.java
index 2e19c52..a8d6eea 100644
--- a/src/main/java/ch/hiddenalpha/unspecifiedgarbage/octetstream/CloseNotifyOutputStream.java
+++ b/src/main/java/ch/hiddenalpha/unspecifiedgarbage/octetstream/CloseNotifyOutputStream.java
@@ -17,9 +17,9 @@ public class CloseNotifyOutputStream extends FilterOutputStream {
     private final Runnable onClose;
     private final AtomicBoolean isFired = new AtomicBoolean(false);
 
-    public CloseNotifyOutputStream(OutputStream out, Runnable onClose) {
+    public CloseNotifyOutputStream( OutputStream out, Runnable onClose ){
         super(out);
-        if(true) throw new UnsupportedOperationException("TODO need to delegate close call");/*TODO*/
+        if( true ) throw new UnsupportedOperationException("TODO need to delegate close call");/*TODO*/
         this.onClose = requireNonNull(onClose);
     }
 
@@ -28,6 +28,10 @@ public class CloseNotifyOutputStream extends FilterOutputStream {
         if (!isFired.getAndSet(true)) {
             onClose.run();
         }
+        // TODO Need to delegate to filtered stream.
+        //      Properly delegating requires to propery handle all the
+        //      special cases around exceptions. See also
+        //      CloseNotifyInputStream which does a similar task.
     }
 
 }
diff --git a/src/main/java/ch/hiddenalpha/unspecifiedgarbage/octetstream/ConcatInputStream.java b/src/main/java/ch/hiddenalpha/unspecifiedgarbage/octetstream/ConcatInputStream.java
index 819e6da..8c89fc0 100644
--- a/src/main/java/ch/hiddenalpha/unspecifiedgarbage/octetstream/ConcatInputStream.java
+++ b/src/main/java/ch/hiddenalpha/unspecifiedgarbage/octetstream/ConcatInputStream.java
@@ -57,12 +57,13 @@ public class ConcatInputStream extends InputStream {
     public void close() throws IOException {
         // Close all remaining sources.
         Exception firstException = null;
-        for( int i = iSrc; i < sources.length; ++i ){
+        for( int i = iSrc ; i < sources.length ; ++i ){
             try{
                 sources[i].close();
             }catch( IOException|RuntimeException ex ){
                 if( firstException == null ){
-                    // Track the exception. But we need to close the remaining ones.
+                    // Track the exception. But we have to close the
+                    // remaining streams regardless of early exceptions.
                     firstException = ex;
                 }else if( firstException != ex ){
                     firstException.addSuppressed(ex);
@@ -72,7 +73,7 @@ public class ConcatInputStream extends InputStream {
         sources = null; // Allow GC
         // Bubble exception if we had any.
         if( firstException instanceof RuntimeException ){
-            throw (RuntimeException) firstException;
+            throw (RuntimeException)firstException;
         }else if( firstException != null ){
             throw (IOException)firstException;
         }
@@ -83,6 +84,8 @@ public class ConcatInputStream extends InputStream {
             InputStream oldSrc = sources[iSrc];
             sources[iSrc] = null;
             iSrc += 1;
+            // Calling close as last step to prevent trouble with our
+            // state as it potentially could throw.
             oldSrc.close();
         }
     }
diff --git a/src/main/java/ch/hiddenalpha/unspecifiedgarbage/shell/ShellUtils.java b/src/main/java/ch/hiddenalpha/unspecifiedgarbage/shell/ShellUtils.java
index 5e2aff2..6c903ec 100644
--- a/src/main/java/ch/hiddenalpha/unspecifiedgarbage/shell/ShellUtils.java
+++ b/src/main/java/ch/hiddenalpha/unspecifiedgarbage/shell/ShellUtils.java
@@ -6,10 +6,13 @@ public class ShellUtils {
     /**
      * Escapes the string so we can use the result in a
      * <a href="https://pubs.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_02_03">double-quoted shell string</a>.
-     * But keeps <a href="https://pubs.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_06_02">parameter expansion</a> alive.
+     * But keeps <a href="https://pubs.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_06_02">parameter expansion</a>
+     * alive.
      * Example usage:
-     *   String path = "pâth \\with ${varToResolve} but a|so €vil chars like spaces, p|pes or * asterisk";
-     *   cmd = "ls '"+ escapeForSnglQuotEverything(path) +"'";
+     * <code>
+     *   String path = "pâth \\with ${varToResolve} but a|so €vil chars like spaces, p|pes or * asterisk";<br/>
+     *   cmd = "ls \""+ escapeForDblQuotButParams(path) +"\"";<br/>
+     * </code>
      */
     public static String escapeForDblQuotButParams( String s ){
         s = s.replace("\\", "\\\\");
@@ -23,8 +26,10 @@ public class ShellUtils {
      * Escapes the string so we can use result in a
      * <a href="https://pubs.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_02_02">single-quoted shell string</a>.
      * Example usage:
-     *   String path = "pâth \\with ${MustNotResolveThisVar} and a|so €vil chars like spaces, p|pes or * asterisk";
-     *   cmd = "ls '"+ escapeForSnglQuotEverything(path) +"'";
+     * <code>
+     *   String path = "pâth \\with ${MustNotResolveThisVar} and a|so €vil chars like spaces, p|pes or * asterisk";<br/>
+     *   cmd = "ls '"+ escapeForSnglQuotEverything(path) +"'";<br/>
+     * </code>
      */
     public static String escapeForSingleQuotEverything( String s ){
         // Cited from "Single-Quotes" in "https://pubs.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html":
diff --git a/src/main/java/ch/hiddenalpha/unspecifiedgarbage/stream/StreamUtils.java b/src/main/java/ch/hiddenalpha/unspecifiedgarbage/stream/StreamUtils.java
index 696d4d3..7d712ee 100644
--- a/src/main/java/ch/hiddenalpha/unspecifiedgarbage/stream/StreamUtils.java
+++ b/src/main/java/ch/hiddenalpha/unspecifiedgarbage/stream/StreamUtils.java
@@ -1,5 +1,8 @@
 package ch.hiddenalpha.unspecifiedgarbage.stream;
 
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
 import java.util.Iterator;
 import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;
@@ -11,28 +14,29 @@ public class StreamUtils {
 
     /**
      * Copies 'is' to 'os' until end of 'is' is reached. (Blocking)
+     *
+     * <p>BTW: Using this function makes no longer sense in projects using java
+     * 9 or later. Just use {@link java.io.InputStream#transferTo(java.io.OutputStream)}
+     * instead.</p>
+     *
      * @return
      *      Count of copied bytes.
      */
-    public static long copy(java.io.InputStream is, java.io.OutputStream os) throws java.io.IOException {
-        byte[] buffer = new byte[1024];
+    public static long copy( java.io.InputStream is, java.io.OutputStream os ) throws java.io.IOException {
+        byte[] buffer = new byte[8192];
         long totalBytes = 0;
         int readLen;
         while( -1 != (readLen=is.read(buffer,0,buffer.length)) ){
             totalBytes += readLen;
-            os.write( buffer , 0 , readLen );
+            os.write(buffer, 0, readLen);
         }
         return totalBytes;
     }
 
-    public static <SRC,DST> java.util.Iterator<DST> map(java.util.Iterator<SRC> src , java.util.function.Function<SRC,DST> mapper) {
+    public static <SRC,DST> java.util.Iterator<DST> map( java.util.Iterator<SRC> src , java.util.function.Function<SRC,DST> mapper ) {
         return new Iterator<DST>() {
-            @Override public boolean hasNext() {
-                return src.hasNext();
-            }
-            @Override public DST next() {
-                return mapper.apply(src.next());
-            }
+            @Override public boolean hasNext() { return src.hasNext(); }
+            @Override public DST next() { return mapper.apply(src.next()); }
         };
     }
 
@@ -41,7 +45,7 @@ public class StreamUtils {
         return t -> seen.add(keyExtractor.apply(t));
     }
 
-    public static <T> Predicate<T> not(Predicate<T> p){
+    public static <T> Predicate<T> not( Predicate<T> p ){
         return e -> !p.test(e);
     }
 
diff --git a/src/main/java/ch/hiddenalpha/unspecifiedgarbage/time/TimeUtils.java b/src/main/java/ch/hiddenalpha/unspecifiedgarbage/time/TimeUtils.java
index ddb1c13..2bb1bfb 100644
--- a/src/main/java/ch/hiddenalpha/unspecifiedgarbage/time/TimeUtils.java
+++ b/src/main/java/ch/hiddenalpha/unspecifiedgarbage/time/TimeUtils.java
@@ -4,17 +4,17 @@ package ch.hiddenalpha.unspecifiedgarbage.time;
 public class TimeUtils {
 
     /**
-     * Delegates to {@link #nanosToEpochMillis(long, long, long)} and assumes
-     * that the 'nanos' value was measure in the same JVM process as this call
-     * here occurs and is not too long back.
+     * Delegates to {@link #nanosToEpochMillis(long, long, long)} and
+     * assumes that the 'nanos' value was measured in the same JVM
+     * process as this call here occurs and is not too long back.
      */
-    public static long nanosToEpochMillis(long nanos) {
+    public static long nanosToEpochMillis( long nanos ){
         return nanosToEpochMillis(nanos, System.nanoTime(), System.currentTimeMillis());
     }
 
-    public static long nanosToEpochMillis(long nanos, long referenceNanos, long referenceEpochMs) {
+    public static long nanosToEpochMillis( long nanos, long referenceNanos, long referenceEpochMs ){
         long diffNs = nanos - referenceNanos;
-        if (diffNs < (Long.MIN_VALUE >> 1) || diffNs > (Long.MAX_VALUE>>1)) {
+        if( diffNs < (Long.MIN_VALUE >> 1) || diffNs > (Long.MAX_VALUE>>1) ){
             // Looks as System.nanoTime() did overflow while measurement. So flip result too.
             diffNs -= Long.MAX_VALUE;
         }
@@ -22,29 +22,38 @@ public class TimeUtils {
     }
 
     /**
-     * Computers cannot represent all existing integers. Due to how integers
-     * are represented in computers, they are not infinite but more like a circle.
-     * Speak when we infinitely increment an integer, it overflows and (usually)
-     * continues to walk around this (imaginary) circle.
+     * Find smallest distance assuming integers overflow "like a circle".
      *
-     * This function takes two of those numbers on this circle and returns the
-     * smallest distance to travel on the circle between them. Here some examples:
-     * - f(7, 13) = 6
-     * - f(-7, +11) = 18
-     * - f(LONG_MIN, LONG_MAX) = 1
-     * - f(-9223372036854775805, 9223372036854775802) = 9
+     * Computers cannot represent all existing integers. Due to how
+     * integers are represented in computers, they are not infinite but
+     * more like a circle.  Speak when we infinitely increment an
+     * integer, it overflows and (usually) continues to walk around this
+     * (imaginary) circle.
+     *
+     * This function takes two of those numbers on this circle and
+     * returns the smallest distance to travel on the circle between
+     * them. Here some examples:
+     * <ul>
+     *   <li>f(7, 13) = 6</li>
+     *   <li>f(-7, +11) = 18</li>
+     *   <li>f(LONG_MIN, LONG_MAX) = 1</li>
+     *   <li>f(-9223372036854775805, 9223372036854775802) = 9</li>
+     * </ul>
      *
      * This can be handy for example in conjunction with {@link System#nanoTime()}.
-     * Because in case of overflows between measuring begNs and endNs a simple subtraction
-     * would lead to uselessly large results. So we can use it as:
-     * long begNs = System.nanoTime();
-     * long endNs = System.nanoTime();
-     * long durationNs = nanosSmallDiff(begNs, endNs);
+     * Because in case of overflows between measuring begNs and endNs a
+     * simple subtraction would lead to uselessly large results. So we
+     * can use it as:
+     * <code>
+     *   long begNs = System.nanoTime();
+     *   long endNs = System.nanoTime();
+     *   long durationNs = nanosSmallDiff(endNs, begNs);
+     * </code>
      *
-     * WARN: Do NOT use this if your distance can reach (LONG_MAX / 2). Because
-     * in this case you would get wrong (too small) results.
+     * WARN: Do NOT use this if your distance can reach (LONG_MAX / 2).
+     * Because in this case you would get wrong (too small) results.
      */
-    public static long nanosSmallDiff(long a, long b) {
+    public static long nanosSmallDiff( long a, long b ){
         return (a - b >= 0) ? a - b : b - a;
     }
 
diff --git a/src/main/shell/BackupByRsync/backup.sh b/src/main/shell/BackupByRsync/backup.sh
new file mode 100755
index 0000000..e557d45
--- /dev/null
+++ b/src/main/shell/BackupByRsync/backup.sh
@@ -0,0 +1,137 @@
+
+# Some tinkering about how I could do backup.
+#
+# Inspired by:
+#   https://linuxconfig.org/how-to-create-incremental-backups-using-rsync-on-linux
+#
+# mount /dev/sdx1 /mnt/x
+#
+
+set -o errexit
+set -o pipefail
+
+readonly NOW_SHORT="$(date -u '+%Y%m%d-%H%M%S')"
+readonly DIR_FROM="/home/${USER:?}/."
+readonly DST_PREFIX="${DIR_FROM:?}"
+readonly DIR_TO="/mnt/x/ROOT_DIR/bkup-rsync/tux-six"
+readonly BACKUP_PATH="${DIR_TO}/${NOW_SHORT}"
+
+
+printHelp () {
+    printf "\n\
+  TODO write help page\n\
+  \n";
+}
+
+
+parseArgs () {
+    local arg0="$0"
+    local isExample="false"
+    while [ $# -gt 0 ]; do
+        local arg="$1"
+        if false; then
+            true
+        elif [ "$arg" == "--help" ]; then
+            printHelp; return 1
+        elif [ "$arg" == "--example" ]; then
+            isExample="true";
+        else
+            echo "Unexpected arg: $arg"; return 1
+        fi
+        shift 1
+    done
+    if ! $isExample; then echo >&2 "Bad args"; return 1; fi
+    return 0
+}
+
+
+run () {
+    if [ ! -e "${DIR_TO:?}" ]; then
+        echo >&2 "Backup root dir does not exist. Abort."
+        return 1
+    fi
+    mkdir -p "${BACKUP_PATH:?}/${DST_PREFIX:?}"
+    rsync --archive --verbose \
+        --link-dest "${DIR_TO}/latest/${DST_PREFIX:?}" \
+        --filter=':- .gitignore' \
+        --exclude=".git/COMMIT_EDITMSG" \
+        --exclude=".git/FETCH_HEAD" \
+        --exclude=".git/ORIG_HEAD" \
+        --exclude=".git/branches" \
+        --exclude=".git/hooks/*.sample" \
+        --exclude=".git/index" \
+        --exclude=".git/info" \
+        --exclude=".git/logs" \
+        --exclude=".git/objects" \
+        --exclude=".git/packed-refs" \
+        --exclude=".git/refs/remotes" \
+        --exclude=".git/refs/tags" \
+        --exclude=".idea" \
+        --exclude="/.NERDTreeBookmarks" \
+        --exclude="/.Xauthority" \
+        --exclude="/.bash_history" \
+        --exclude="/.config/VirtualBox/HostInterfaceNetworking-vboxnet0-Dhcpd.leases*" \
+        --exclude="/.config/VirtualBox/HostInterfaceNetworking-vboxnet0-Dhcpd.log*" \
+        --exclude="/.config/VirtualBox/VBoxSVC.log*" \
+        --exclude="/.config/VirtualBox/compreg.dat" \
+        --exclude="/.config/VirtualBox/selectorwindow.log*" \
+        --exclude="/.config/VirtualBox/vbox-ssl-cacertificate.crt" \
+        --exclude="/.config/VirtualBox/xpti.dat" \
+        --exclude="/.config/libreoffice" \
+        --exclude="/.config/GIMP" \
+        --exclude="/.config/JetBrains" \
+        --exclude="/.gdb_history" \
+        --exclude="/.lesshst" \
+        --exclude="/.profile" \
+        --exclude="/.vimrc" \
+        --exclude="/.xsession-errors" \
+        --exclude="/.xsession-errors.old" \
+        --exclude="/mnt" \
+        --exclude="/.android" \
+        --exclude="/.cache" \
+        --exclude="/.config/chromium" \
+        --exclude="/.config/inkscape" \
+        --exclude="/.local/share" \
+        --exclude="/.m2/repository" \
+        --exclude="/.mozilla/firefox" \
+        --exclude="/.squirrel-sql" \
+        --exclude="/.viking-maps" \
+        --exclude="/Downloads" \
+        --exclude="/crashdumps" \
+        --exclude="/images" \
+        --exclude="/projects/apple/cups" \
+        --exclude="/projects/gnu" \
+        --exclude="/projects/lua" \
+        --exclude="/projects/misc/OpenSSL" \
+        --exclude="/projects/misc/OpenVPN" \
+        --exclude="/projects/misc/busybox" \
+        --exclude="/projects/misc/cgit" \
+        --exclude="/projects/misc/dash" \
+        --exclude="/projects/misc/endlessh" \
+        --exclude="/projects/misc/jssc" \
+        --exclude="/projects/misc/libqrencode" \
+        --exclude="/projects/misc/mbedtls" \
+        --exclude="/projects/misc/openbox" \
+        --exclude="cee-misc-lib/external" \
+        --exclude="cee-misc-lib/tmp" \
+        --exclude="/tmp" \
+        --exclude="/virtualbox-*" \
+        --exclude="/vmshare" \
+        "${DIR_FROM:?}" \
+        "${BACKUP_PATH:?}/${DST_PREFIX}" \
+        ;
+    (cd "${DIR_TO:?}" &&
+        rm -f latest &&
+        ln --symbolic "${NOW_SHORT:?}" latest
+    )
+}
+
+
+main () {
+    parseArgs "$@"
+    if [ $? -ne 0 ]; then exit 2; fi
+    run
+}
+
+
+main "$@"