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VCTA Detour Wednesday/Omvejsonsdag – new paths for your wheels
Sep 24th, 2020 by miki

The Danish Cyclists’ Federation (Cyklistforbundet) throws a yearly month long event called BIKE TO WORK (“Vi Cykler Til Arbejde” aka. VCTA) nudging employees of Danish workplaces to use their bike for commuting. Teams are formed by the employees and team statistics are available both internally and between workplaces for the teams to compete in the number of kilometres travelled and number of active days. See f.x. the statistics for the two teams of my employer Vestergaard. Of course my outdoor, social, competitive, and sometimes a bit extreme, mindset can’t miss such a chance to commit to an all-in full month bike relay race with myself and some distant (300 km to HQ) colleagues.

As a part of the VCTA month of cycling one day is designated to taking an unknown route to work, dubbed “Detour Wednesday” (“Omvejsonsdag“). This is to inspire the individual to find new routes and get some fresh input on the surroundings. This year it was Wednesday September 23th, and the event even includes a draw of an electric powered bike amongst participants documenting their detour appropriately.

For your enjoyment, below are some visual impressions from my nice detour in the Tjæreborg/Bramming area (of Western Jutland, Denmark). Even though I have been to all these places before you do sense a place a lot different on the bike than by other means.

All The Maps

Being the dev/hacker/tinkerer/geo person that I am, although not extremely well-versed in HTML/javascript, I have also made a quick throw together of a visualisation on top of Leaflet and OpenStreetMap of all the tracks I’ve recorded yet during VCTA. Find it here; tools.mikini.dk/vcta.

My VCTA tracks pr. 2020-09-24 visualised by some hackish javascript on tools.mikini.dk/vcta.

Out

The start of the Wadden Sea dykes at Roborg near Tjæreborg. National cycle route 1 (N1 – Vestkystruten) runs along here. Location: 55.45083;8.56325

In front of Sneum Sluse, where Sneum Å joins the sea. Location: 55.43321;8.60780

Along the dyke between Sneum Sluse and Darum. Approximate location: 55.42917;8.62244

Home

Crossing Sneum Å again, this time in-land approximately 12 km upstream from Sneum Sluse. Location: 55.49637;8.69648

Following national cycle route 6 (N6 – Esbjerg-København) and regional cycle route 10 heading back towards Ålbæk, Opsneum and Tjæreborg. Location: 55.49874;8.69664

Tracks

The tracks as recorded by Endomondo;

The tracks as recorded by OpenTracks (Application: F-Droid, Github, Google Play, OSM Dashboard: F-Droid, Github, Google Play).

Outgoing track as recorded by OpenTracks.

Homegoing track as recorded by OpenTracks.

GeoNames.org database id becoming a meteorological location reference
Aug 20th, 2020 by miki

Looking at weather forecasts in my native Denmark I have always noticed a location reference used by DMI, Danmarks Meteorologiske Institut (en:Danish Meteorological Institute). Somehow I managed to not look into the details of that before now.

But this morning while scouting for rain showers and trying out the forecast on the new website of Yr (the long time open data weather service from Norwegian Broadcasting Corporation (NRK) and the Norwegian Meteorological institute (MET)), as kindly suggested by the YR main site which uses the old site by default, I saw the same reference included in the URL.

A closer look at different service’s forecast URLs for my usual whereabouts in Tjæreborg, Denmark, Europe, Earth reveals (se summary below) that they all share this reference and that it stems from the GeoNames.org (wikipedia article) database’s integer reference to the location:

This particular piece of data is described as a field in the “geoname” table of the GeoNames.org main database, and referred to as “geonameid” in the documentation:

geonameid         : integer id of record in geonames database

The contents of the GeoNames.org database is licensed under the Creative Commons Attribution 4.0 International (aka. “CC BY 4.0”, SPDX ID:”CC-BY-4.0″) and available both for your own download and perusal (documentation here) or using web services on geonames.org.

Note, however, that GeoNames.org accumulates a wealth of data sources that according to the OpenStreetMap project might contain copyrighted data. Together with the attribution requirements of its CC BY license this causes OpenStreetMap to not accept data from GeoNames.org into the project’s, ODbL licensed, database.

Fun fact: in Norwegian “yr” actually means drizzle (da:støvregn)
Practical hint: OpenSearch entry for GeoNames.org: http://www.geonames.org/opensearch-description.xml (to add in current browser: go here->find “Plugins”->click “opensearch plugin”)

The Weather Services

2611610 on GeoNames.org

“Get”ting from web service

$ wget -q -O- "https://secure.geonames.org/get?geonameId=2611610&username=demo"
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<geoname>
    <toponymName>Tjæreborg</toponymName>
    <name>Tjæreborg</name>
    <lat>55.46457</lat>
    <lng>8.57968</lng>
    <geonameId>2611610</geonameId>
    <countryCode>DK</countryCode>
    <countryName>Denmark</countryName>
    <fcl>P</fcl>
    <fcode>PPL</fcode>
    <fclName>city, village,...</fclName>
    <fcodeName>populated place</fcodeName>
    <population>2146</population>
    <adminCode1 ISO3166-2="83">21</adminCode1>
    <adminName1>South Denmark</adminName1>
    <asciiName>Tjaereborg</asciiName>
    <alternateNames>Tjaereborg,Tjæreborg</alternateNames>
    <elevation/>
    <srtm3>12</srtm3>
    <astergdem>11</astergdem>
    <continentCode>EU</continentCode>
    <adminCode2>561</adminCode2>
    <adminName2>Esbjerg Kommune</adminName2>
    <alternateName lang="post">6731</alternateName>
    <alternateName lang="unlc">DKTJA</alternateName>
    <alternateName lang="link">https://en.wikipedia.org/wiki/Tj%C3%A6reborg%2C_Denmark</alternateName>
    <alternateName>Tjæreborg</alternateName>
    <timezone dstOffset="2.0" gmtOffset="1.0">Europe/Copenhagen</timezone>
    <bbox>
        <west>8.57175</west>
        <north>55.46907</north>
        <east>8.58762</east>
        <south>55.46008</south>
        <accuracyLevel>0</accuracyLevel>
    </bbox>
</geoname>
$

Extracting from “Gazetteer” exports

$ wget -q https://download.geonames.org/export/dump/DK.zip
$ unzip DK.zip 
Archive:  DK.zip
  inflating: readme.txt              
  inflating: DK.txt                  
$ grep ^2611610 DK.txt
2611610	Tjæreborg	Tjaereborg	Tjaereborg,Tjæreborg	55.46457	8.57968	P	PPL	DK		21	561			2146		12	Europe/Copenhagen	2017-10-18
$
Amending an open OSM changeset on command line (by hand)
Jul 25th, 2020 by miki

WARNING: as OSM user “mmd” wisely points out (in comment to OSM diary for this post) the sort of thing described here is dangerous to do by hand, and should not be done on the main production instances (there are testing instances for playing around with the API, a little documentation here).
He also points out that the feature packed JOSM editor actually supports continuing a changeset regardless of where it has been initiated. So if you just need to continue working on a changeset (but remember the 1 hour idle timeout) be sure to check out the JSOM upload documentation. Thanks mmd, for being the sane voice ;).

During an editing session the Android OpenStreetMap editor Vespucci crashed on me, which made the mapping UI unusable (objects greyed out and unable to select or edit, had to purge all data to recover functionality). Luckly, I could still navigate the menus, upload changes and opt to not close the changeset. Now, I had long wondered whether the OSM API allowed to continue amending changes to an open changeset from some other editor, so the quest began.

I had the intention of adding a tag representing the name of a building in Esbjerg known as “ISC Huset” (ISC is an engineering consultancy, see wikipedia, and more about the construction), which houses a number of healtcare clinics. The building’s address is Borgergade 70, 6700 Esbjerg (current address node).

This blog post willl attempt to actually add the tag by hand on the command line.

References to OSM objects used:

Option summary for GNU wget used to do HTTP requests below:

  • -nv (or –no-verbose): only report errors and basic information
  • -O- (or –output-document=-): write output to standard out (stdout)
  • –user=<user name>: authenticate as <user name> using HTTP Basic authentication
  • –ask-password: ask on command line for HTTP Basic authentication password
  • –post-data=”<data>”: initiate a HTTP POST request with <data> as payload
  • –server-response (or -S): show full HTTP headers of server response

NOTE: I’ve broken some long output lines replicated below to make it fit the blog, but inserted an escape character (\) before the inserted newline to help copy’n’pasting.

Retrieve changeset metadata

Lets start by looking at the changeset’s metadata.

This can be done by issuing an unauthenticated GET request to the “/api/0.6/changeset/<changeset id>” endpoint.

Note that the ‘changeset’ element has the attribute ‘open=”true”‘ required to be able to modify the changeset. The editor used to create the changeset needs to have done this without explicitly closing it (Vespucci & JOSM closes by default but can be configured not to, iD always closes).

$ wget -nv -O- http://api.openstreetmap.org/api/0.6/changeset/88490797
<?xml version="1.0" encoding="UTF-8"?>
<osm version="0.6" generator="CGImap 0.8.3 (802 thorn-02.openstreetmap.org)" copyright="OpenStreetMap and contributors"\
 attribution="http://www.openstreetmap.org/copyright" license="http://opendatacommons.org/licenses/odbl/1-0/">
 <changeset id="88490797" created_at="2020-07-25T09:51:30Z" open="true" user="mikini" uid="2051"\
 min_lat="55.4654072" min_lon="8.4378053" max_lat="55.5258532" max_lon="8.4639026" comments_count="0" changes_count="68">
  <tag k="source" v="survey;research"/>
  <tag k="locale" v="da-DK"/>
  <tag k="created_by" v="Vespucci 14.1.4.0"/>
  <tag k="comment" v="Details at Klevestien &amp; Borgergade in Esbjerg and Tarp."/>
 </changeset>
</osm>
2020-07-25 14:26:52 URL:http://api.openstreetmap.org/api/0.6/changeset/88490797 [709] -> "-" [1]
$

Pinging the changeset with an empty osmChange structure

To test that the changeset is open, and that we can authenticate correctly, lets try amending it with an empty osmChange structure.

This can be done by issuing an authenticated POST request to the “/api/0.6/changeset/<changeset id>/upload” endpoint.

This also seem to reset the 60 minute timer used for auto-closing the changeset (see mention of “idle timeout” in changeset wiki article).

$ wget -nv -O- --user=mikini --ask-password https://api.openstreetmap.org/api/0.6/changeset/88490797/upload --post-data="<osmChange></osmChange>"
Password for user ‘mikini’: 
Authentication selected: Basic realm="Web Password", charset="UTF-8"
<?xml version="1.0" encoding="UTF-8"?>
<diffResult version="0.6" generator="CGImap 0.8.3 (8531 thorn-03.openstreetmap.org)" copyright="OpenStreetMap and contributors"\
 attribution="http://www.openstreetmap.org/copyright" license="http://opendatacommons.org/licenses/odbl/1-0/"/>
2020-07-25 14:27:20 URL:https://api.openstreetmap.org/api/0.6/changeset/88490797/upload [278] -> "-" [1]
$

Procedure to change the building

The API’s “changeset/<changeset id>/upload” method supports only modifications encoded in the osmChange format which requires changes to be described as complete way/node/relation objects. That is, you can not ask the API to “add this tag to this way”, you need instead to describe the modified way completely saying “this way now looks like this”, including anything (like node references or existing tags) that was not modified. So to make a modificatino to the building’s way we need to retrieve the current version, modify it as needed and upload the complete new way.

Thus the procedure contains these steps;

  1. Retrieve current building (GET /way/*)
  2. Modify building data (locally)
  3. Amend changeset (POST /changeset/*/upload)

Retrieving current building (GET /way/*)

This can be done by issuing an unauthenticated GET request to the “/api/0.6/way/<way id>” endpoint.

The stdin splitter ‘tee’ is used here to both show the result in terminal and put it into file 185369466_v3.osc that we can use for amending the way with the wanted modifications.

$ wget -nv -O- http://api.openstreetmap.org/api/0.6/way/185369466|tee 185369466_v3.osc
<?xml version="1.0" encoding="UTF-8"?>
<osm version="0.6" generator="CGImap 0.8.3 (28697 thorn-01.openstreetmap.org)" copyright="OpenStreetMap and contributors"\
 attribution="http://www.openstreetmap.org/copyright" license="http://opendatacommons.org/licenses/odbl/1-0/">
 <way id="185369466" visible="true" version="3" changeset="84400254" timestamp="2020-04-30T09:35:21Z" user="mikini" uid="2051">
  <nd ref="1959614623"/>
  <nd ref="1959614727"/>
  <nd ref="6299449794"/>
  <nd ref="1959614650"/>
  <nd ref="1959614630"/>
  <nd ref="6299449793"/>
  <nd ref="1959614765"/>
  <nd ref="7466482063"/>
  <nd ref="7466482064"/>
  <nd ref="7466482065"/>
  <nd ref="7466482062"/>
  <nd ref="1959614729"/>
  <nd ref="1959614623"/>
  <tag k="building" v="yes"/>
 </way>
</osm>
2020-07-25 14:54:30 URL:http://api.openstreetmap.org/api/0.6/way/185369466 [769] -> "-" [1]
$

Modify building data (locally)

Now we need to build an osmChange file out of the existing <way>…</way> element from the output above describing the wanted building. This involves;

  1. removing the <xml> tag (maybe not needed, but it is not mentioned at all in the osmChange documentation)
  2. replacing <osm> with <osmChange>
  3. adding a <modify> element to the <osmChange> element, containing the existing <way>
  4. update the “changeset” attribute to the changeset we’re amending
  5. amending the contents of <way> with the wanted <tag>s

Use your favorite editor (emacs would be my preference) to load the 185369466_v3.osm file, make the modifications and save it as 185369466_v4.osc. OSM tags are a XML empty-element tags containing the OSM tag’s key and value in the “k” and “v” attributes, thus the “name” tag of the building I needed to add would be ‘<tag k=”name” v=”ISC Huset”/>’, I also added some other related tags (“source:name” and “website”).

The finished .osc file now looks like this;

$ cat 185369466_v4.osc
<osmChange>
  <modify>
    <way id="185369466" visible="true" version="3" changeset="88490797" timestamp="2020-04-30T09:35:21Z" user="mikini" uid="2051">
      <nd ref="1959614623"/>
      <nd ref="1959614727"/>
      <nd ref="6299449794"/>
      <nd ref="1959614650"/>
      <nd ref="1959614630"/>
      <nd ref="6299449793"/>
      <nd ref="1959614765"/>
      <nd ref="7466482063"/>
      <nd ref="7466482064"/>
      <nd ref="7466482065"/>
      <nd ref="7466482062"/>
      <nd ref="1959614729"/>
      <nd ref="1959614623"/>
      <tag k="building" v="yes"/>
      <tag k="name" v="ISC Huset"/>
      <tag k="source:name" v="sign;website"/>
      <tag k="website" v="https://www.isc.dk/isc-huset-esbjerg/"/>
    </way>
  </modify>
</osmChange>
$

Wdiff’ing against the .osm source shows exactly what changed (additions between “{+” & “+}”, removals between “[-” & “-]”);

$ wdiff 185369466_v3.osm 185369466_v4.osc
[-<?xml version="1.0" encoding="UTF-8"?>
<osm version="0.6" generator="CGImap 0.8.3 (28697 thorn-01.openstreetmap.org)" copyright="OpenStreetMap and contributors"\
 attribution="http://www.openstreetmap.org/copyright" license="http://opendatacommons.org/licenses/odbl/1-0/">-]{+<osmChange>
  <modify>+}
    <way id="185369466" visible="true" version="3" [-changeset="84400254"-] {+changeset="88490797"+} timestamp="2020-04-30T09:35:21Z" user="mikini" uid="2051">
      <nd ref="1959614623"/>
      <nd ref="1959614727"/>
      <nd ref="6299449794"/>
      <nd ref="1959614650"/>
      <nd ref="1959614630"/>
      <nd ref="6299449793"/>
      <nd ref="1959614765"/>
      <nd ref="7466482063"/>
      <nd ref="7466482064"/>
      <nd ref="7466482065"/>
      <nd ref="7466482062"/>
      <nd ref="1959614729"/>
      <nd ref="1959614623"/>
      <tag k="building" v="yes"/>
      {+<tag k="name" v="ISC Huset"/>
      <tag k="source:name" v="sign;website"/>
      <tag k="website" v="https://www.isc.dk/isc-huset-esbjerg/"/>+}
    </way>
[-</osm>-]
  {+</modify>
</osmChange>+}
$

Amend changeset (POST /changeset/*/upload)

Now, we’ll again use the changeset upload method but this time supplying our actual osmChange elemet in the .osc file.

The output is a bit elaborate, because I had enabled full output from wget while debugging what changes to the <way> element was needed for the server to accept the upload (only the “changeset” attribute needs to match the open changeset as outlined in the “Modify building data” above). I’ve highligted the actual server response telling that the changes were accepted and way #185369466 is now at v4.

$ wget -S -O- --user=mikini --ask-password https://api.openstreetmap.org/api/0.6/changeset/88490797/upload --post-file=185369466_v4.osc
Password for user ‘mikini’: 
--2020-07-25 15:44:41--  https://api.openstreetmap.org/api/0.6/changeset/88490797/upload
Resolving api.openstreetmap.org (api.openstreetmap.org)... 130.117.76.12, 130.117.76.13, 130.117.76.11, ...
Connecting to api.openstreetmap.org (api.openstreetmap.org)|130.117.76.12|:443... connected.
HTTP request sent, awaiting response... 
  HTTP/1.1 401 Unauthorized
  Date: Sat, 25 Jul 2020 13:44:41 GMT
  Server: Apache/2.4.29 (Ubuntu)
  Strict-Transport-Security: max-age=31536000; includeSubDomains; preload
  Expect-CT: max-age=0, report-uri="https://openstreetmap.report-uri.com/r/d/ct/reportOnly"
  WWW-Authenticate: Basic realm="Web Password", charset="UTF-8"
  Cache-Control: no-cache
  Strict-Transport-Security: max-age=31536000; includeSubDomains; preload
  Expect-CT: max-age=0, report-uri="https://openstreetmap.report-uri.com/r/d/ct/reportOnly"
  Content-Length: 22
  Content-Type: text/plain; charset=utf-8
  Keep-Alive: timeout=5, max=100
  Connection: Keep-Alive
Authentication selected: Basic realm="Web Password", charset="UTF-8"
Reusing existing connection to api.openstreetmap.org:443.
HTTP request sent, awaiting response... 
  HTTP/1.1 200 OK
  Date: Sat, 25 Jul 2020 13:44:42 GMT
  Server: Apache/2.4.29 (Ubuntu)
  Strict-Transport-Security: max-age=31536000; includeSubDomains; preload
  Expect-CT: max-age=0, report-uri="https://openstreetmap.report-uri.com/r/d/ct/reportOnly"
  Content-Encoding: identity
  Cache-Control: private, max-age=0, must-revalidate
  Strict-Transport-Security: max-age=31536000; includeSubDomains; preload
  Expect-CT: max-age=0, report-uri="https://openstreetmap.report-uri.com/r/d/ct/reportOnly"
  Vary: Accept-Encoding
  Content-Type: application/xml; charset=utf-8
  Keep-Alive: timeout=5, max=99
  Connection: Keep-Alive
  Transfer-Encoding: chunked
Length: unspecified [application/xml]
Saving to: ‘STDOUT’
- [<=> ] 0 --.-KB/s
<?xml version="1.0" encoding="UTF-8"?>
<diffResult version="0.6" generator="CGImap 0.8.3 (8537 thorn-03.openstreetmap.org)" copyright="OpenStreetMap and contributors"\
 attribution="http://www.openstreetmap.org/copyright" license="http://opendatacommons.org/licenses/odbl/1-0/">
 <way old_id="185369466" new_id="185369466" new_version="4"/>
</diffResult>
- [ <=> ] 353 --.-KB/s in 0s

2020-07-25 15:44:42 (20,3 MB/s) - written to stdout [353]

$

Result

That was it, the building is now named in OSM, in a changset amended by hand.

Take a look at https://www.openstreetmap.org/way/185369466/.

GitHub CLI on Ubuntu LTS (16.04 & 18.04)
Mar 4th, 2020 by miki

Inspired by a John Sullivan (of FSF) tweet asking about opinions on the new and shiny MS(TM) GitHub(TM) CLI(TM) tool named “gh”(TM) I wanted to try it out on one of my Ubuntu LTS systems (16.04).

I’ve always disliked the proprietary and centralised monoculture of github, especially after that thing with MS, so I’ve mostly avoided using the service for code I produce myself. If interested in independence and decentralisation maybe you should read up on that long fabled subject? Thus I’ve never even tried the predecessor “hub”(TM) tool (main page), and exactly how it differs from this new “CLI” thing is not obviously apparent from the communications.

Nevertheless, the “gh” tool, officially dubbed  GitHub CLI, being distributed under MIT license and written in go(lang) (afterwards, found out that this is indeed also applicable to the predecessing “hub” tool) made me curious enough to go see what they’re up to. Maybe its not that sinister a plot and they really just want to improve the independent and freely available mechanisms for source code storage, distribution and maintenance (I wish)?

TL:DR

A fairly recent (2019-09) version of go, >=1.13, is required so some gymnastics are needed to make stuff work on older distros like Ubuntu’s LTS (with 5 years support from Canonical). Anyway, this is what I did to build a useable “gh” ELF executable (20 MiB!, se below), this is from source, no precompiled stuff, no snaps. It was done on Ubuntu 16.04 (xenial) but I’ve been somewhat careful to inspect that things ought to be good for 18.04 (bionic) too. Non-essential output from the commands is largely discarded here. See Gory Details section below for the full monty.

Add go PPA & install packages

$ sudo add-apt-repository ppa:longsleep/golang-backports
$ sudo apt update
$ sudo apt install golang
$ go version
go version go1.13.4 linux/amd64

Clone repo & build

$ cd
$ git clone https://github.com/cli/cli .githubcli
$ cd .githubcli
$ make

Setup PATH & test

$ echo 'export PATH="$HOME/.githubcli/bin:$PATH"' >> ~/.bash_profile
$ bash --login
$ gh
Work seamlessly with GitHub from the command line.

GitHub CLI is in early stages of development, and we'd love to hear your
feedback at <https://forms.gle/umxd3h31c7aMQFKG7>

Usage:
  gh [command]

Available Commands:
  help        Help about any command
  issue       Create and view issues
  pr          Create, view, and checkout pull requests
  repo        Create, clone, fork, and view repositories

Flags:
      --help              Show help for command
  -R, --repo OWNER/REPO   Select another repository using the OWNER/REPO format
      --version           Show gh version

Use "gh [command] --help" for more information about a command.
subcommand is required
$

Trying it out

Randomly picked one of my few github repos, it contains some js experiments on parsing NMEA formatted coordinates, rather uninterestingly empty.

Clone

user@host:~$ gh repo clone mikini/coordinates 
Notice: authentication required
Press Enter to open github.com in your browser... 

<auth session in browser>

Authentication complete. Press Enter to continue...

Cloning into 'coordinates'...
remote: Enumerating objects: 10, done.
remote: Total 10 (delta 0), reused 0 (delta 0), pack-reused 10
Unpacking objects: 100% (10/10), done.
Checking connectivity... done.
user@host:~$

An ordinary OAuth request was spawned for authentication on https://github.com/login/oauth/authorize. The javascript executed in the browser seemed to interact with the gh tool through a local TCP connection on localhost:45454 which was the redirection target on authorisation (URL parameter: “redirect_uri=http://localhost:45454/callback”). The socket was rightfully not bound after the authentication had succeeded but this is definitely an attack vector, albeit hopefully only for locally running processes.

Listing issues & prs

user@host:~$ cd coordinates/
user@host:~$:~/coordinates$ gh issue list

Issues for mikini/coordinates

There are no open issues
miki@vcas-miki2:~/coordinates$ gh pr view
no open pull requests found for branch "master"
miki@vcas-miki2:~/coordinates$

Creating issues

miki@vcas-miki2:~/coordinates$ gh issue create

Creating issue in mikini/coordinates

? Title Testing gh
? Body <Received>
? What's next? Preview in browser
Opening github.com/mikini/coordinates/issues/new/ in your browser.
miki@vcas-miki2:~/coordinates$

miki@vcas-miki2:~/coordinates$ gh issue create

Creating issue in mikini/coordinates

? Title Testing gh tool
? Body <Received>
? What's next? [Use arrows to move, type to filter]
> Preview in browser
Submit
Cancel

https://github.com/mikini/coordinates/issues/1
miki@vcas-miki2:~/coordinates$

On the first issue creation interaction I selected “preview in browser” which opened a draft issue in the browser, and dumped me back into the shell on the command line. The second interaction actually resulted in #1.

Gory Details

PPA options

The golang-backports PPA is maintained independently by Simon Eisenmann (credits: ~longsleep, @github, stdin.xyz) and carries packages up to:

There’s also an official PPA from the golang project (~gophers) which however only carries packages up to 1.11 for both.

Full (mostly) installation dump

Add go PPA, install packages

user@host:~$ sudo add-apt-repository ppa:longsleep/golang-backports
Golang 1.8, 1.9, 1.10, 1.11, 1.12, 1.13 and 1.14 PPA for Ubuntu
 More info: https://launchpad.net/~longsleep/+archive/ubuntu/golang-backports
Press [ENTER] to continue or ctrl-c to cancel adding it

gpg: keyring `/tmp/tmpvnuym97a/secring.gpg' created
gpg: keyring `/tmp/tmpvnuym97a/pubring.gpg' created
gpg: requesting key 56A3D45E from hkp server keyserver.ubuntu.com
gpg: /tmp/tmpvnuym97a/trustdb.gpg: trustdb created
gpg: key 56A3D45E: public key "Launchpad PPA for Simon Eisenmann" imported
gpg: Total number processed: 1
gpg:               imported: 1  (RSA: 1)
OK
user@host:~$

user@host:~$ sudo apt update
Hit:1 http://dk.archive.ubuntu.com/ubuntu xenial InRelease
Get:2 http://dk.archive.ubuntu.com/ubuntu xenial-updates InRelease [109 kB] 
...
...
Get:37 http://security.ubuntu.com/ubuntu xenial-security/universe DEP-11 64x64 Icons [194 kB]
Get:38 http://security.ubuntu.com/ubuntu xenial-security/multiverse amd64 DEP-11 Metadata [2.468 B]
Fetched 7.614 kB in 3s (2.346 kB/s) 
Reading package lists... Done
Building dependency tree 
Reading state information... Done
419 packages can be upgraded. Run 'apt list --upgradable' to see them.
user@host:~$

user@host:~$ apt list --upgradeable golang -a
Listing... Done
golang/xenial,xenial 2:1.13~1longsleep1+xenial all [upgradable from: 2:1.6-1ubuntu4]
golang/xenial,xenial,now 2:1.6-1ubuntu4 all [installed,upgradable to: 2:1.13~1longsleep1+xenial]

user@host:~$

user@host:~$ sudo apt install golang
Reading package lists... Done
Building dependency tree 
Reading state information... Done
The following packages were automatically installed and are no longer required:
golang-1.6 golang-1.6-doc golang-1.6-go golang-1.6-src
Use 'sudo apt autoremove' to remove them.
The following additional packages will be installed:
golang-1.13 golang-1.13-doc golang-1.13-go golang-1.13-src golang-doc golang-go golang-src
Recommended packages:
golang-1.13-race-detector-runtime
The following NEW packages will be installed
golang-1.13 golang-1.13-doc golang-1.13-go golang-1.13-src
The following packages will be upgraded:
golang golang-doc golang-go golang-src
4 to upgrade, 4 to newly install, 0 to remove and 413 not to upgrade.
Need to get 60,2 MB of archives.
After this operation, 322 MB of additional disk space will be used.
Do you want to continue? [Y/n] 
Get:1 http://ppa.launchpad.net/longsleep/golang-backports/ubuntu xenial/main amd64 golang-1.13-src amd64 1.13.4-1longsleep1+xenial [12,7 MB]
Get:2 http://ppa.launchpad.net/longsleep/golang-backports/ubuntu xenial/main amd64 golang-1.13-go amd64 1.13.4-1longsleep1+xenial [44,9 MB]
Get:3 http://ppa.launchpad.net/longsleep/golang-backports/ubuntu xenial/main amd64 golang-1.13-doc all 1.13.4-1longsleep1+xenial [2.542 kB]
Get:4 http://ppa.launchpad.net/longsleep/golang-backports/ubuntu xenial/main amd64 golang-1.13 all 1.13.4-1longsleep1+xenial [25,2 kB]
Get:5 http://ppa.launchpad.net/longsleep/golang-backports/ubuntu xenial/main amd64 golang-src amd64 2:1.13~1longsleep1+xenial [3.838 B]
Get:6 http://ppa.launchpad.net/longsleep/golang-backports/ubuntu xenial/main amd64 golang-go amd64 2:1.13~1longsleep1+xenial [23,0 kB]
Get:7 http://ppa.launchpad.net/longsleep/golang-backports/ubuntu xenial/main amd64 golang-doc all 2:1.13~1longsleep1+xenial [3.880 B]
Get:8 http://ppa.launchpad.net/longsleep/golang-backports/ubuntu xenial/main amd64 golang all 2:1.13~1longsleep1+xenial [3.826 B]
Fetched 60,2 MB in 5s (10,8 MB/s) 
Selecting previously unselected package golang-1.13-src.
(Reading database ... 460737 files and directories currently installed.)
Preparing to unpack .../golang-1.13-src_1.13.4-1longsleep1+xenial_amd64.deb ...
Unpacking golang-1.13-src (1.13.4-1longsleep1+xenial) ...
Selecting previously unselected package golang-1.13-go.
Preparing to unpack .../golang-1.13-go_1.13.4-1longsleep1+xenial_amd64.deb ...
Unpacking golang-1.13-go (1.13.4-1longsleep1+xenial) ...
Selecting previously unselected package golang-1.13-doc.
Preparing to unpack .../golang-1.13-doc_1.13.4-1longsleep1+xenial_all.deb ...
Unpacking golang-1.13-doc (1.13.4-1longsleep1+xenial) ...
Selecting previously unselected package golang-1.13.
Preparing to unpack .../golang-1.13_1.13.4-1longsleep1+xenial_all.deb ...
Unpacking golang-1.13 (1.13.4-1longsleep1+xenial) ...
Preparing to unpack .../golang-src_2%3a1.13~1longsleep1+xenial_amd64.deb ...
Unpacking golang-src (2:1.13~1longsleep1+xenial) over (2:1.6-1ubuntu4) ...
Preparing to unpack .../golang-go_2%3a1.13~1longsleep1+xenial_amd64.deb ...
Unpacking golang-go (2:1.13~1longsleep1+xenial) over (2:1.6-1ubuntu4) ...
Preparing to unpack .../golang-doc_2%3a1.13~1longsleep1+xenial_all.deb ...
Unpacking golang-doc (2:1.13~1longsleep1+xenial) over (2:1.6-1ubuntu4) ...
Preparing to unpack .../golang_2%3a1.13~1longsleep1+xenial_all.deb ...
Unpacking golang (2:1.13~1longsleep1+xenial) over (2:1.6-1ubuntu4) ...
Processing triggers for man-db (2.7.5-1) ...
Setting up golang-1.13-src (1.13.4-1longsleep1+xenial) ...
Setting up golang-1.13-go (1.13.4-1longsleep1+xenial) ...
Setting up golang-1.13-doc (1.13.4-1longsleep1+xenial) ...
Setting up golang-1.13 (1.13.4-1longsleep1+xenial) ...
Setting up golang-src (2:1.13~1longsleep1+xenial) ...
Setting up golang-go (2:1.13~1longsleep1+xenial) ...
Setting up golang-doc (2:1.13~1longsleep1+xenial) ...
Setting up golang (2:1.13~1longsleep1+xenial) ...
user@host:~$ 

user@host:~$ go version
go version go1.13.4 linux/amd64
user@host:~$ 

Clone repo & build

user@host:~$ git clone https://github.com/cli/cli .githubcli
Cloning into '.githubcli'...
remote: Enumerating objects: 168, done.
remote: Counting objects: 100% (168/168), done.
remote: Compressing objects: 100% (100/100), done.
remote: Total 5577 (delta 93), reused 122 (delta 67), pack-reused 5409
Receiving objects: 100% (5577/5577), 7.53 MiB | 2.61 MiB/s, done.
Resolving deltas: 100% (3269/3269), done.
Checking connectivity... done.
user@host:~$ 

user@host:~$ cd .githubcli
user@host:~/.githubcli (master=)$ make
go: downloading github.com/google/shlex v0.0.0-20191202100458-e7afc7fbc510
go: downloading github.com/mitchellh/go-homedir v1.1.0
go: downloading github.com/mattn/go-colorable v0.1.6
go: downloading github.com/spf13/cobra v0.0.6
go: downloading gopkg.in/yaml.v3 v3.0.0-20200121175148-a6ecf24a6d71
go: downloading github.com/mattn/go-isatty v0.0.12
go: downloading golang.org/x/text v0.3.2
go: extracting github.com/mitchellh/go-homedir v1.1.0
go: extracting github.com/mattn/go-colorable v0.1.6
go: extracting github.com/google/shlex v0.0.0-20191202100458-e7afc7fbc510
go: extracting github.com/spf13/cobra v0.0.6
go: extracting github.com/mattn/go-isatty v0.0.12
go: downloading golang.org/x/sys v0.0.0-20200223170610-d5e6a3e2c0ae
go: downloading golang.org/x/crypto v0.0.0-20200219234226-1ad67e1f0ef4
go: downloading github.com/mgutz/ansi v0.0.0-20170206155736-9520e82c474b
go: downloading github.com/briandowns/spinner v1.9.0
go: extracting gopkg.in/yaml.v3 v3.0.0-20200121175148-a6ecf24a6d71
go: downloading github.com/hashicorp/go-version v1.2.0
go: downloading github.com/spf13/pflag v1.0.5
go: downloading github.com/AlecAivazis/survey/v2 v2.0.7
go: downloading github.com/kballard/go-shellquote v0.0.0-20180428030007-95032a82bc51
go: downloading github.com/charmbracelet/glamour v0.1.1-0.20200304134224-7e5c90143acc
go: extracting github.com/mgutz/ansi v0.0.0-20170206155736-9520e82c474b
go: extracting github.com/spf13/pflag v1.0.5
go: extracting github.com/hashicorp/go-version v1.2.0
go: downloading gopkg.in/yaml.v2 v2.2.8
go: downloading github.com/cpuguy83/go-md2man/v2 v2.0.0
go: downloading github.com/henvic/httpretty v0.0.4
go: extracting github.com/kballard/go-shellquote v0.0.0-20180428030007-95032a82bc51
go: extracting github.com/briandowns/spinner v1.9.0
go: extracting github.com/AlecAivazis/survey/v2 v2.0.7
go: downloading github.com/fatih/color v1.7.0
go: extracting github.com/charmbracelet/glamour v0.1.1-0.20200304134224-7e5c90143acc
go: downloading github.com/yuin/goldmark v1.1.24
go: downloading github.com/microcosm-cc/bluemonday v1.0.2
go: extracting gopkg.in/yaml.v2 v2.2.8
go: extracting github.com/henvic/httpretty v0.0.4
go: downloading github.com/olekukonko/tablewriter v0.0.4
go: downloading github.com/muesli/reflow v0.1.0
go: extracting github.com/fatih/color v1.7.0
go: extracting github.com/microcosm-cc/bluemonday v1.0.2
go: extracting github.com/cpuguy83/go-md2man/v2 v2.0.0
go: extracting golang.org/x/sys v0.0.0-20200223170610-d5e6a3e2c0ae
go: extracting github.com/muesli/reflow v0.1.0
go: extracting github.com/olekukonko/tablewriter v0.0.4
go: downloading golang.org/x/net v0.0.0-20200219183655-46282727080f
go: extracting github.com/yuin/goldmark v1.1.24
go: downloading github.com/alecthomas/chroma v0.7.2-0.20200304075647-34d9c7143bf5
go: downloading github.com/mattn/go-runewidth v0.0.8
go: downloading github.com/muesli/termenv v0.4.0
go: downloading github.com/russross/blackfriday/v2 v2.0.1
go: extracting golang.org/x/crypto v0.0.0-20200219234226-1ad67e1f0ef4
go: extracting github.com/mattn/go-runewidth v0.0.8
go: extracting github.com/russross/blackfriday/v2 v2.0.1
go: downloading github.com/shurcooL/sanitized_anchor_name v1.0.0
go: extracting github.com/alecthomas/chroma v0.7.2-0.20200304075647-34d9c7143bf5
go: extracting github.com/shurcooL/sanitized_anchor_name v1.0.0
go: extracting github.com/muesli/termenv v0.4.0
go: downloading github.com/dlclark/regexp2 v1.2.0
go: downloading github.com/lucasb-eyer/go-colorful v1.0.3
go: downloading github.com/google/goterm v0.0.0-20190703233501-fc88cf888a3f
go: downloading github.com/danwakefield/fnmatch v0.0.0-20160403171240-cbb64ac3d964
go: extracting golang.org/x/text v0.3.2
go: extracting github.com/google/goterm v0.0.0-20190703233501-fc88cf888a3f
go: extracting github.com/danwakefield/fnmatch v0.0.0-20160403171240-cbb64ac3d964
go: extracting golang.org/x/net v0.0.0-20200219183655-46282727080f
go: extracting github.com/lucasb-eyer/go-colorful v1.0.3
go: extracting github.com/dlclark/regexp2 v1.2.0
go: finding github.com/spf13/cobra v0.0.6
go: finding github.com/AlecAivazis/survey/v2 v2.0.7
go: finding github.com/henvic/httpretty v0.0.4
go: finding github.com/google/shlex v0.0.0-20191202100458-e7afc7fbc510
go: finding github.com/mgutz/ansi v0.0.0-20170206155736-9520e82c474b
go: finding gopkg.in/yaml.v3 v3.0.0-20200121175148-a6ecf24a6d71
go: finding github.com/spf13/pflag v1.0.5
go: finding github.com/hashicorp/go-version v1.2.0
go: finding github.com/mitchellh/go-homedir v1.1.0
go: finding github.com/briandowns/spinner v1.9.0
go: finding golang.org/x/text v0.3.2
go: finding github.com/cpuguy83/go-md2man/v2 v2.0.0
go: finding github.com/charmbracelet/glamour v0.1.1-0.20200304134224-7e5c90143acc
go: finding github.com/kballard/go-shellquote v0.0.0-20180428030007-95032a82bc51
go: finding github.com/mattn/go-colorable v0.1.6
go: finding gopkg.in/yaml.v2 v2.2.8
go: finding github.com/russross/blackfriday/v2 v2.0.1
go: finding github.com/mattn/go-isatty v0.0.12
go: finding github.com/fatih/color v1.7.0
go: finding golang.org/x/crypto v0.0.0-20200219234226-1ad67e1f0ef4
go: finding github.com/muesli/termenv v0.4.0
go: finding golang.org/x/sys v0.0.0-20200223170610-d5e6a3e2c0ae
go: finding github.com/shurcooL/sanitized_anchor_name v1.0.0
go: finding github.com/yuin/goldmark v1.1.24
go: finding github.com/alecthomas/chroma v0.7.2-0.20200304075647-34d9c7143bf5
go: finding github.com/google/goterm v0.0.0-20190703233501-fc88cf888a3f
go: finding github.com/dlclark/regexp2 v1.2.0
go: finding github.com/lucasb-eyer/go-colorful v1.0.3
go: finding github.com/muesli/reflow v0.1.0
go: finding github.com/microcosm-cc/bluemonday v1.0.2
go: finding github.com/danwakefield/fnmatch v0.0.0-20160403171240-cbb64ac3d964
go: finding github.com/olekukonko/tablewriter v0.0.4
go: finding github.com/mattn/go-runewidth v0.0.8
go: finding golang.org/x/net v0.0.0-20200219183655-46282727080f
user@host:~/.githubcli (master=)$ 

Cursory inspection of exec

user@host:~/.githubcli (master=)$ ls -l bin/gh
-rwxrwxr-x 1 user user 21097487 Mar  4 18:03 bin/gh
user@host:~/.githubcli (master=)$ 

user@host:~/.githubcli (master=)$ file bin/gh
bin/gh: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked, interpreter /lib64/l, not stripped
user@host:~/.githubcli (master=)$ 

user@host:~/.githubcli (master=)$ ldd bin/gh
	linux-vdso.so.1 =>  (0x00007ffdc4329000)
	libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007fb1018c2000)
	libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007fb1014f8000)
	/lib64/ld-linux-x86-64.so.2 (0x00007fb101adf000)
user@host:~/.githubcli (master=)$ 

user@host:~/.githubcli (master=)$ nm -D bin/gh
                 U abort
00000000004fd140 T _cgo_panic
000000000045bf10 T _cgo_topofstack
00000000004fd190 T crosscall2
                 U __errno_location
                 U __fprintf_chk
                 U fputc
                 U free
                 U freeaddrinfo
                 U fwrite
                 U gai_strerror
                 U getaddrinfo
                 U getnameinfo
                 U malloc
                 U mmap
                 U munmap
                 U nanosleep
                 U pthread_attr_destroy
                 U pthread_attr_getstacksize
                 U pthread_attr_init
                 U pthread_cond_broadcast
                 U pthread_cond_wait
                 U pthread_create
                 U pthread_detach
                 U pthread_mutex_lock
                 U pthread_mutex_unlock
                 U pthread_sigmask
                 U setenv
                 U sigaction
                 U sigaddset
                 U sigemptyset
                 U sigfillset
                 U sigismember
                 U __stack_chk_fail
                 U stderr
                 U strerror
                 U unsetenv
                 U __vfprintf_chk
user@host:~/.githubcli (master=)$ 

Setup PATH & test

user@host:~/.githubcli (master=)$ cd
user@host:~$ echo 'export PATH="$HOME/.githubcli/bin:$PATH"' >> ~/.bash_profile
user@host:~$ bash --login
user@host:~$ gh
Work seamlessly with GitHub from the command line.

GitHub CLI is in early stages of development, and we'd love to hear your
feedback at <https://forms.gle/umxd3h31c7aMQFKG7>

Usage:
  gh [command]

Available Commands:
  help        Help about any command
  issue       Create and view issues
  pr          Create, view, and checkout pull requests
  repo        Create, clone, fork, and view repositories

Flags:
      --help              Show help for command
  -R, --repo OWNER/REPO   Select another repository using the OWNER/REPO format
      --version           Show gh version

Use "gh [command] --help" for more information about a command.
subcommand is required
user@host:~$
A havfrue stopping by?: Deep Energy pipelay vessel in Esbjerg
Oct 2nd, 2019 by miki

Came by Esbjerg Harbour on September 24th 2019 and saw what was obviously a cable ship docked at the quay. A giant ship and I immediately thought that the mermaid might be closing in on Jutland. Some quick drive-by pictures and vessel details below:

 

New sighting on 2019-11-03:
image
image

JV article about ship and ongoing upgrades causing noise.

Itch: eog core dump on Galaxy 7 panorama image
Jun 10th, 2019 by miki

  • Took some photos with my Galaxy 7. Some were panoramas.
  • EOG crashed while loading them.
  • Memory was low.
  • Maybe related to previously experienced missing EOI marker issue with Samsung camera application.

Will investigate later and amend the post (promise!).

Commandline Dump

$ free; find . -size +25M -exec bash -c 'ls -l {}; eog {}; echo' \;; free
              total        used        free      shared  buff/cache   available
Mem:        7746692     5767656      843228      317764     1135808     1271048
Swap:       7950332     5113012     2837320
-rw-rw-r-- 1 miki miki 39926496 Jun 10 19:25 ./20190609_184124.jpg

** (eog:23320): CRITICAL **: eog_reload_plugin_activate: assertion 'G_IS_MENU (model)' failed
eog: ../../../../src/cairo-xlib-surface-shm.c:619: _cairo_xlib_shm_pool_create: Assertion `*ptr != ((void *)0)' failed.
bash: line 1: 23320 Aborted                 (core dumped) eog ./20190609_184124.jpg

-rw-rw-r-- 1 miki miki 38286099 Jun 10 19:26 ./20190609_183714.jpg

** (eog:23332): CRITICAL **: eog_reload_plugin_activate: assertion 'G_IS_MENU (model)' failed
eog: ../../../../src/cairo-xlib-surface-shm.c:619: _cairo_xlib_shm_pool_create: Assertion `*ptr != ((void *)0)' failed.
bash: line 1: 23332 Aborted                 (core dumped) eog ./20190609_183714.jpg

-rw-rw-r-- 1 miki miki 36181801 Jun  9 17:13 ./20190609_160437.jpg

** (eog:23343): CRITICAL **: eog_reload_plugin_activate: assertion 'G_IS_MENU (model)' failed

** (eog:23343): CRITICAL **: eog_reload_plugin_deactivate: assertion 'G_IS_MENU (menu)' failed

-rw-rw-r-- 1 miki miki 39059177 Jun 10 19:25 ./20190609_184146.jpg

** (eog:23354): CRITICAL **: eog_reload_plugin_activate: assertion 'G_IS_MENU (model)' failed
eog: ../../../../src/cairo-xlib-surface-shm.c:619: _cairo_xlib_shm_pool_create: Assertion `*ptr != ((void *)0)' failed.
bash: line 1: 23354 Aborted                 (core dumped) eog ./20190609_184146.jpg

              total        used        free      shared  buff/cache   available
Mem:        7746692     5773448      495604      659944     1477640      922956
Swap:       7950332     5112700     2837632
$ 

 

[Danish] S&S: Android-x86 og Chromebook
Jun 8th, 2019 by miki

Lidt flere dråber i Spørgsmål&Svar-kategorien fra Facebook.

Når jeg endelig forvilder mig derind, og går på opdagelse i de tekniske grupper, ender det ofte med at får jeg skrevet en fristil i forsøget på at hjælpe.

Denne gang en snak om Android på “PC”, og basale digitale processeringsbehov for den almindelige dansker.

Spørgsmål

Stillet i gruppen “Danske Android Brugere “:

Er der nogen som ved, om man kan få en pc med Android system?

Svar

Mit svar:

Som andre omtaler, kan der fås en uofficiel variant af det frie styresystem Android til x86-arkitekturen (den gængse Intel/AMD-baserede computer kendt som “personlig computer”).

Det projekt lever på https://www.android-x86.org/. Installationsvejledning på engelsk er på https://www.android-x86.org/installhowto.html. Man kan både installere som multiboot på samme disk som et eksisterende operativsystem, starte fra en ekstern disk (USB-medie, cd/dvdrom e.l.) eller evt. køre i en virtuel maskine på et eksisterende operativsystem (VirtualBox,QEMU/KVM, VMware Player/Workstation).

Jeg har kun erfaring med livedisk boot fra USB og VM, og der synes jeg ikke altid tingene spiller perfekt, så forvent ikke en helt problemfri oplevelse.

“Android på PC” er på kanten af noget understøttet, hvor man ofte er på egen hånd. Nogle af folkene bag Andoid-x86 forsøgte at lave en kommerciel forretning på det, hvor det var tanken at sælge det som færdige hardwareenheder, RemixOS – https://en.wikipedia.org/wiki/Remix_OS, men det gik ikke så godt og er lukket ned igen.

Hvis behovet bare er “en bærbar computer uden for meget vrøvl”, så er en færdig Chromebook med Chrome OS (der ligesom Android også er bygget på GNU/Linux) eller noget af det der dyre Frugt-udstyr nok det mest tilgængelige (men jeg fornemmer at pris også kunne være en faktor?). Til forskel fra traditionelle operativsystemer til computere, er Chrome OS dog møntet specifikt på at få dig til at bruge Googles webbaserede tjenester (mere om softwaren bag på https://www.chromium.org/chromium-os), så hverken software eller hardware er beregnet til at lagre data på selve enheden, og der er sjældent meget diskplads tilgængelig til f.eks. billeder.

Et hurtigt kig på markedet identificerer Acer Chromebook 15 (https://www.edbpriser.dk/produkt/acer-chromebook-15-cb515-1h-c7kg/) og Lenovo S330 (https://www.edbpriser.dk/produkt/lenovo-chromebook-s330-81jw-3292492/) som populære Chromebook i 2k kr.-klassen, men kender ikke maskinerne specifikt.

God jagt :).

Automating wav to ogg conversion
Jun 6th, 2019 by miki

Needed some space on the disk.

Had some music, some of it were wav files.

Threw together this script to transmogify it into ogg using ffmpeg.

Statistics say that 24 wav files occupying 1,7 GiB was made into 24 ogg files occupying 105 MiB, a reduction to ~6% (du -h calculates 2^10 numbers but uses SI 10^3 prefixes..).

miki@filly:~/Music$ find . -iname "*.wav" -print0 | sed s/.wav/.ogg/g |du --files0-from=- -h -c|tail -1
105M	total
miki@filly:~/Music$ find . -iname "*.wav" -print0 | sed s/.wav/.wav/g |du --files0-from=- -h -c|tail -1
1,7G total
miki@filly:~/Music$ find . -iname "*.wav" -print0 | sed s/.wav/.ogg/g |du --files0-from=- -h |wc -l
24
miki@filly:~/Music$

Script

Install prerequisite ffmpeg and ffprobe utilities on apt distributions by doing “apt install ffmpeg”.

BEWARE: script deletes any wav files in current directory and below without warning if conversion to ogg is fine according to ffmpeg return code and stdout/err.

Manual confirmation of all deletions can be enabled by uncommenting line 8 (CONFIRM=..).

It could (very) easily be amended for conversion between any container or compression format supported by ffmpeg by replacing “wav” and “ogg” in glob pattern and OGG variable definition (for completeness also in echo output…).

miki@filly:~/wavtest$ cat ~/hometools/wav2ogg.sh
#! /bin/bash
#
# Make .ogg out of all .wav in cwd and below, remove .wav!
#
# When converting remove only if conversion is ok.
# ffprobe any present .ogg and check if playtime is same as wav, remove only if all is good.

#CONFIRM=-i # confirm deletion?

REQS="ffmpeg ffprobe"
which $REQS  >/dev/null
if [ ! $? -eq 0 ]; then
    echo We need $REQS to do stuff!
    exit 1
fi

shopt -s globstar nullglob nocaseglob # enable 2-star magic
for f in **/*.wav; do
    OGG=$(dirname "$f")/$(basename "$f" wav)ogg
    echo -n "$f: "
    if [ ! -f "$OGG" ]; then
        echo -en "\e[33mno ogg\e[0m"
        CONVERT=1
    else
        echo -en "\e[32malready there\e[0m"
        if [ ! "$(ffprobe "$f" 2>&1|grep Duration|cut -d, -f1)" = "$(ffprobe "$OGG" 2>&1|grep Duration|cut -d, -f1)" ]; then
            echo -en " - \e[31mogg corrupt\e[0m"
            CONVERT=1
            rm $CONFIRM "$OGG"
        else
            OGGOK=1
        fi
    fi
    if [ $CONVERT ]; then
        echo -en " - \e[33mconverting\e[0m"
        OUT=$(ffmpeg -loglevel error -i "$f" "$OGG" 2>&1)
        if [ ! $? -eq 0 ]; then
            echo -e " \e[31mfatal error!\e[0m\nffmpeg output was:\n\n$OUT\n"
            rm $CONFIRM "$OGG"
        elif [ ! -z "$OUT" ]; then
            echo -e " \e[31mnon-fatal error!\e[0m\nffmpeg output was:\n\n$OUT\n"
        else
            OGGOK=1
        fi
    fi
    if [ $OGGOK ]; then
        echo -e " - all good removing wav"
        rm $CONFIRM "$f"
    fi
done
miki@filly:~/wavtest$ 

Usage and Output

Before

miki@filly:~/wavtest$ ls -lR
.:
total 59964
drwxrwxr-x 3 miki miki     4096 Jun  6 22:33 one
-rw-rw-r-- 1 miki miki 61390864 Jun  6 22:32 Sordid Affair (Man Without Country Version).wav

./one:
total 30720
drwxrwxr-x 3 miki miki     4096 Jun  6 22:34 two
-rw-rw-r-- 1 miki miki 31451304 Jun  6 22:30 Vision Man MASTER.wav

./one/two:
total 55352
-rw-rw-r-- 1 miki miki 56675660 Jun  6 22:34 Bye Barat - Going For Broke (UNKWON´s Autumn Remix) LIM_02.wav
drwxrwxr-x 2 miki miki     4096 Jun  6 22:34 three

./one/two/three:
total 375112
-rw-rw-r-- 1 miki miki 384108056 Jun  6 22:30 Rigoremix - Pornographe - Final2.wav
miki@filly:~/wavtest$ du -hs .
509M	.
miki@filly:~/wavtest$

During

In real life, also in technicolor!

miki@filly:~/wavtest$ ~/hometools/wav2ogg.sh 
one/two/Bye Barat - Going For Broke (UNKWON´s Autumn Remix) LIM_02.wav: no ogg - converting - all good removing wav
one/two/three/Rigoremix - Pornographe - Final2.wav: no ogg - converting - all good removing wav
one/Vision Man MASTER.wav: no ogg - converting - all good removing wav
Sordid Affair (Man Without Country Version).wav: no ogg - converting - all good removing wav
miki@filly:~/wavtest$

After

miki@filly:~/wavtest$ ls -lR
.:
total 4952
drwxrwxr-x 3 miki miki    4096 Jun  6 22:35 one
-rw-rw-r-- 1 miki miki 5066460 Jun  6 22:35 Sordid Affair (Man Without Country Version).ogg

./one:
total 2528
drwxrwxr-x 3 miki miki    4096 Jun  6 22:34 two
-rw-rw-r-- 1 miki miki 2580752 Jun  6 22:35 Vision Man MASTER.ogg

./one/two:
total 4680
-rw-rw-r-- 1 miki miki 4785594 Jun  6 22:34 Bye Barat - Going For Broke (UNKWON´s Autumn Remix) LIM_02.ogg
drwxrwxr-x 2 miki miki    4096 Jun  6 22:35 three

./one/two/three:
total 19456
-rw-rw-r-- 1 miki miki 19922936 Jun  6 22:35 Rigoremix - Pornographe - Final2.ogg
miki@filly:~/wavtest$ du -hs .
31M .
miki@filly:~/wavtest$

Metadata

ffmpeg does some nice metadata conversions out of the box;

miki@filly:~/Music$ ffprobe ~/"wavbak/Delayscape  A Short While Rigolin Edit Audaccity.wav" 2>&1| grep Input -A 1000
Input #0, wav, from '/home/miki/wavbak/Delayscape  A Short While Rigolin Edit Audaccity.wav':
  Metadata:
    title           : Delayscape - A Short While (Rigolin Edit)
    artist          : rigolin
    comment         : Love Melody
    date            : 2018
  Duration: 00:06:33.97, bitrate: 3072 kb/s
    Stream #0:0: Audio: pcm_f32le ([3][0][0][0] / 0x0003), 48000 Hz, 2 channels, flt, 3072 kb/s
miki@filly:~/Music$ ffprobe "./Delayscape - Heinz Beauvaix/Soundcloud/Delayscape  A Short While Rigolin Edit Audaccity.ogg" 2>&1| grep Input -A 1000
Input #0, ogg, from './Delayscape - Heinz Beauvaix/Soundcloud/Delayscape  A Short While Rigolin Edit Audaccity.ogg':
  Duration: 00:06:33.97, start: 0.000000, bitrate: 99 kb/s
    Stream #0:0: Audio: vorbis, 48000 Hz, stereo, fltp, 112 kb/s
    Metadata:
      ENCODER         : Lavc56.60.100 libvorbis
      TITLE           : Delayscape - A Short While (Rigolin Edit)
      ARTIST          : rigolin
      comment         : Love Melody
      DATE            : 2018
miki@filly:~/Music$

Source Material

Libreboot’ing an X200 using a CH341a based programmer
Jun 4th, 2019 by miki

Here’s a preliminary HOWTO from my recent external flashing of the BIOS ROM on a Lenovo X200 thinkpad (Wikipedia). The particular firmware flashed was a Libreboot build for this machine (instructions for X200 and details of the external flashing procedure) but anything goes (but anything may not be useful, though).

I’ll amend this HOWTO with more detailed instructions and pictures in the following days (warning: a prediction) to hopefully make it more complete and useful for the vary inhabitants of LibreBootLand.

Some parts

A programmer kit was bought on AliExpress for $4.20 containing a USB programmer board and an SOIC-8 clip which ended up not being used as the particular X200 had a SOIC-16 chip so a separately ordered SOIC-16 chip ($3.11)  was used.

“MinProgramment” aka. CH341a Programmer

Buy: https://www.aliexpress.com/item/32898599200.html @ $4.20

The programmer is based on the WCH CH341a chip which is an USB <-> seriel/parallel/uart interface. The manufacturer WCH being  WinChipHead aka. WCH (Nanjing QinHeng Electronics Co.,Ltd) (maybe also aka. WCH-IC (Jiangsu Qinheng Co., Ltd)). There are lots of options for buying board varieties based on the CH341a chip, to get you started here is a BangGood search and an AliExpress search.

Boards like this has also been described by others including a deduced schematic, EEVblog critique of the I/O pin power on similar boards (not yet confirmed whether that is true for this programmer too, I guess so, but at least one flashing done without damage) and a mention on hackaday of other board types.

There are a bunch of downloads from the WCH site regarding the chip including  a Chinese datasheet, no English language documentation seems to be available from the manufacturer however. There are some English editions of the datasheet to be found, of unknown origin. They seem plausible enough to use, though. Somebody has attempted to collect documentation about the chip in a Git repository.

The SOIC-16 Clip (aka. Pomona 5252)

Buy: https://www.aliexpress.com/item/32869145935.html @ $3.11

To attach physically to the Macronix MX25L6405D flash memory chip in a SOIC-16 package present on the X200 in question (words are that this is the norm although the board can be populated with a SOIC-8 too) a clip that matches the pins of the SOIC-16 package is needed. I bought the one mentioned above for $3.11 at random from AliExpress and this worked fine. In the pictures the wiring is hooked up correctly to the programmer to allow for flashing as described below.

 

WARNING: Below is still a draft made from mental notes! Ask me if you need more information or check back soon (I promise).

Connections

6405 <-> CH341a

MISO<->MIOS (label error, should be MISO)

MOSI<->MOSI

CLK <-> CLK

CS <-> SS

GND <-> GND

First tried driving the the flash chip from VDD on ch341a but this was unsuccessful, no chip could be found, so the 6405 was hooked up to external 3.3v power supply with supply GND connected to GND on CH341a to align the ground potential between ch341a I/O supply and 6405 supply (important!).

Preparations

Machine being flashed

Update Embedded Controller

To get the latest ECP (Embedded Controller Program) from Lenovo (no free alternative exists) containing software for the MCU controlling low level hardware like battery charging/keyboard/backlight stuff you need to update the BIOS which also updates the ECP. Most recent version for X200 is “BIOS: 3.22 / ECP: 1.07“. This is not needed if you already have these versions on the machine, check current versions by pressing ThinkVantage during boot and choosing “Enter Setup”.

If your system has a Windows installation download and run the “BIOS Update Utility“executeable. Else you’ll need to get the “BIOS Update Bootable CD” and somehow get it on a CD and find a CD-ROM drive. Alternatively on a Linux system the CD file system can be extracted and added to Grub to be directly bootable. Below was done on an Ubuntu 16.04 system:

$ sudo apt install genisoimage syslinux
$ wget -q https://download.lenovo.com/ibmdl/pub/pc/pccbbs/mobiles/6duj48us.iso
$ geteltorito 6duj48us.iso > 6duj48us.img
Booting catalog starts at sector: 20
Manufacturer of CD: NERO BURNING ROM
Image architecture: x86
Boot media type is: harddisk
El Torito image starts at sector 27 and has 75776 sector(s) of 512 Bytes
Image has been written to stdout ….
$ sudo cp 6duj48us.im /boot
$ sudo cp /usr/lib/syslinux/memdisk /boot
$ sudo nano /etc/grub.d/40_custom
<add lines below to the end of file, preserve the “exec tail…” line>
menuentry “BIOS Update” {
linux16 /memdisk
initrd16 /6duj48us.im
}
$ sudo update-grub

Reboot, press <left shift> key while booting to access Grub, choose BIOS Update menu entry and follow the Lenovo update procedure. To start flashing it requires both a connected power supply and also a working, non-exhausted battery (!) mounted in the machine. This is tiresome for owners of worn out batteries…

Some notes about the flashing process can be found in the documentation of a patch set for the Lenovo BIOS.

Machine doing the programming

Install Flashrom

sudo apt install flashrom

ch341a support in flashrom

LibreBoot

Retrieve

Download the stable LibreBoot firmware: https://www.mirrorservice.org/sites/libreboot.org/release/stable/20160907/rom/grub/libreboot_r20160907_grub_x200_8mb.tar.xz

The brave will of course want to compile it themselves.

$ cd
$ wget https://www.mirrorservice.org/sites/libreboot.org/release/stable/20160907/rom/grub/libreboot_r20160907_grub_x200_8mb.tar.xz
--2019-06-07 07:35:21--  https://www.mirrorservice.org/sites/libreboot.org/release/stable/20160907/rom/grub/libreboot_r20160907_grub_x200_8mb.tar.xz
Resolving www.mirrorservice.org (www.mirrorservice.org)... 212.219.56.184, 2001:630:341:12::184
Connecting to www.mirrorservice.org (www.mirrorservice.org)|212.219.56.184|:443... connected.
HTTP request sent, awaiting response... 200 OK
Length: 1632800 (1,6M) [application/x-xz]
Saving to: ‘libreboot_r20160907_grub_x200_8mb.tar.xz’

libreboot_r20160907_grub_x200_8mb.tar.xz 100%[================================================================================>]   1,56M  --.-KB/s    in 0,1s    

2019-06-07 07:35:21 (13,9 MB/s) - ‘libreboot_r20160907_grub_x200_8mb.tar.xz’ saved [1632800/1632800]
$ tar tf libreboot_r20160907_grub_x200_8mb.tar.xz 
libreboot_r20160907_grub_x200_8mb/
libreboot_r20160907_grub_x200_8mb/x200_8mb_deqwertz_txtmode.rom
libreboot_r20160907_grub_x200_8mb/x200_8mb_esqwerty_txtmode.rom
libreboot_r20160907_grub_x200_8mb/x200_8mb_frazerty_txtmode.rom
libreboot_r20160907_grub_x200_8mb/x200_8mb_frdvbepo_txtmode.rom
libreboot_r20160907_grub_x200_8mb/x200_8mb_itqwerty_txtmode.rom
libreboot_r20160907_grub_x200_8mb/x200_8mb_svenska_txtmode.rom
libreboot_r20160907_grub_x200_8mb/x200_8mb_ukdvorak_txtmode.rom
libreboot_r20160907_grub_x200_8mb/x200_8mb_ukqwerty_txtmode.rom
libreboot_r20160907_grub_x200_8mb/x200_8mb_usdvorak_txtmode.rom
libreboot_r20160907_grub_x200_8mb/x200_8mb_usqwerty_txtmode.rom
libreboot_r20160907_grub_x200_8mb/x200_8mb_deqwertz_vesafb.rom
libreboot_r20160907_grub_x200_8mb/x200_8mb_esqwerty_vesafb.rom
libreboot_r20160907_grub_x200_8mb/x200_8mb_frazerty_vesafb.rom
libreboot_r20160907_grub_x200_8mb/x200_8mb_frdvbepo_vesafb.rom
libreboot_r20160907_grub_x200_8mb/x200_8mb_itqwerty_vesafb.rom
libreboot_r20160907_grub_x200_8mb/x200_8mb_svenska_vesafb.rom
libreboot_r20160907_grub_x200_8mb/x200_8mb_ukdvorak_vesafb.rom
libreboot_r20160907_grub_x200_8mb/x200_8mb_ukqwerty_vesafb.rom
libreboot_r20160907_grub_x200_8mb/x200_8mb_usdvorak_vesafb.rom
libreboot_r20160907_grub_x200_8mb/x200_8mb_usqwerty_vesafb.rom
libreboot_r20160907_grub_x200_8mb/ChangeLog
libreboot_r20160907_grub_x200_8mb/NEWS
libreboot_r20160907_grub_x200_8mb/version
libreboot_r20160907_grub_x200_8mb/versiondate
$

Customise MAC address

As the MAC address of the ethnernet PHY is stored in the flash, yo have your X200 ethernet MAC address correspond to the sticker on the back of the machine, and also avoid a potential but improbable DHCP/ARP conflict, the MAC address from the label/ifconfig from the existing system must be embedded into the flash file that we are going to program into the flash chip.

For this a tool called ich9gen is needed, this is a part of the libreboot repository and we need to build it ourselves.

Build ich9gen

$ git clone https://notabug.org/libreboot/libreboot
Cloning into 'libreboot'...
remote: Counting objects: 29080, done.
remote: Compressing objects: 100% (9855/9855), done.
remote: Total 29080 (delta 18748), reused 27899 (delta 18057)
Receiving objects: 100% (29080/29080), 63.90 MiB | 11.13 MiB/s, done.
Resolving deltas: 100% (18748/18748), done.
Checking connectivity... done.
$ cd libreboot/projects/ich9gen/sources
$ make
gcc -I. -Wall -Wextra -g -std=c99 -c src/ich9deblob.c -o obj/ich9deblob.o
gcc -I. -Wall -Wextra -g -std=c99 -c src/common/descriptor_gbe.c -o obj/common/descriptor_gbe.o
gcc -I. -Wall -Wextra -g -std=c99 -c src/descriptor/descriptor.c -o obj/descriptor/descriptor.o
gcc -I. -Wall -Wextra -g -std=c99 -c src/gbe/gbe.c -o obj/gbe/gbe.o
gcc -I. -Wall -Wextra -g -std=c99 -c src/common/x86compatibility.c -o obj/common/x86compatibility.o
gcc -I. -Wall -Wextra -g -std=c99 obj/ich9deblob.o obj/common/descriptor_gbe.o \
	obj/common/x86compatibility.o obj/descriptor/descriptor.o obj/gbe/gbe.o \
	 -o ich9deblob
gcc -I. -Wall -Wextra -g -std=c99 -c src/ich9gen.c -o obj/ich9gen.o
gcc -I. -Wall -Wextra -g -std=c99 -c src/ich9gen/mkdescriptor.c -o obj/ich9gen/mkdescriptor.o
gcc -I. -Wall -Wextra -g -std=c99 -c src/ich9gen/mkgbe.c -o obj/ich9gen/mkgbe.o
gcc -I. -Wall -Wextra -g -std=c99 obj/ich9gen.o obj/ich9gen/mkdescriptor.o obj/ich9gen/mkgbe.o \
 obj/common/descriptor_gbe.o \
	obj/common/x86compatibility.o obj/descriptor/descriptor.o obj/gbe/gbe.o \
	 -o ich9gen
gcc -I. -Wall -Wextra -g -std=c99 -c src/demefactory.c -o obj/demefactory.o
gcc -I. -Wall -Wextra -g -std=c99 obj/demefactory.o obj/common/descriptor_gbe.o \
	obj/common/x86compatibility.o obj/descriptor/descriptor.o obj/gbe/gbe.o \
	 -o demefactory
$

Run ich9gen

Running ich9gen itself generates the flash descriptor (fd) header including possible configuration section where the MAC address is stored for the gigabit ethernet (gbe) PHY onboard the ICH9 chipset. When run six 12 KiB files for respectively 4, 8 and 16 MiB binary images and chipsets including (gbe) and excluding (nogbe) gigabit ethernet PHY are generated.

“aa:bb:cc:dd:ee:ff” in the commandline should be replaced with the actual 12 hex digits from the label on the machine or by running ifconfig on the machine using the existing Lenovo BIOS.

$ cd ~/libreboot_r20160907_grub_x200_8mb/
$ ~/libreboot/projects/ich9gen/sources/ich9gen --macaddress aa:bb:cc:dd:ee:ff
You selected to change the MAC address in the Gbe section. This has been done.

The modified gbe region has also been dumped as src files: mkgbe.c, mkgbe.h
To use these in ich9gen, place them in src/ich9gen/ and re-build ich9gen.

descriptor and gbe successfully written to the file: ich9fdgbe_4m.bin
Now do: dd if=ich9fdgbe_4m.bin of=libreboot.rom bs=1 count=12k conv=notrunc
(in other words, add the modified descriptor+gbe to your ROM image)

descriptor and gbe successfully written to the file: ich9fdgbe_8m.bin
Now do: dd if=ich9fdgbe_8m.bin of=libreboot.rom bs=1 count=12k conv=notrunc
(in other words, add the modified descriptor+gbe to your ROM image)

descriptor and gbe successfully written to the file: ich9fdgbe_16m.bin
Now do: dd if=ich9fdgbe_16m.bin of=libreboot.rom bs=1 count=12k conv=notrunc
(in other words, add the modified descriptor+gbe to your ROM image)

descriptor successfully written to the file: ich9fdnogbe_4m.bin
Now do: dd if=ich9fdnogbe_4m.bin of=yourrom.rom bs=1 count=4k conv=notrunc
(in other words, add the modified descriptor to your ROM image)

descriptor successfully written to the file: ich9fdnogbe_8m.bin
Now do: dd if=ich9fdnogbe_8m.bin of=yourrom.rom bs=1 count=4k conv=notrunc
(in other words, add the modified descriptor to your ROM image)

descriptor successfully written to the file: ich9fdnogbe_16m.bin
Now do: dd if=ich9fdnogbe_16m.bin of=yourrom.rom bs=1 count=4k conv=notrunc
(in other words, add the modified descriptor to your ROM image)

Apply Flash Descriptor to Binary

$ cd ~/libreboot_r20160907_grub_x200_8mb/
$ cp -v x200_8mb_usqwerty_vesafb{,_customised}.rom
'x200_8mb_usqwerty_vesafb.rom' -> 'x200_8mb_usqwerty_vesafb_customised.rom'
$ dd if=ich9fdgbe_8m.bin of=x200_8mb_usqwerty_vesafb_customised.rom bs=1 count=12k conv=notrunc
12288+0 records in
12288+0 records out
12288 bytes (12 kB, 12 KiB) copied, 0,0299453 s, 410 kB/s
$

Procedure

Programmer Setup Validation / Lenovo BIOS backup

flashrom -p ch341a_spi -c MX25L6405D -r rom1.bin

flashrom -p ch341a_spi -c MX25L6405D -r rom2.bin

flashrom -p ch341a_spi -c MX25L6405D -r rom3.bin

flashrom -p ch341a_spi -c MX25L6405D -r rom4.bin

flashrom -p ch341a_spi -c MX25L6405D -r rom5.bin

cmp rom{1,2}.bin

cmp rom{1,3}.bin

cmp rom{1,4}.bin

cmp rom{1,5}.bin

Flashing

$ sudo flashrom -p ch341a_spi -c MX25L6405D -w ~/libreboot_r20160907_grub_x200_8mb/x200_8mb_usqwerty_vesafb_customised.rom
$

Accounts of LibreBoot Flashing

Embedded Controller (EC) information

[Danish] Webmaster! Skalér nu de billeder!
May 1st, 2019 by miki

Tænk hvor meget trafik, processerings- og ventetid der ville være sparet hvis nogen gad at overveje hvad billeder på en hjemmeside anvendes til og tilpasse de transmitterede data derefter!

Her et enkelt sølle eksempel af mange observerede (ingen særlig grund til at klandre den specifikke afsender her, blev bare trigget af at klikke på et link i et nyhedsbrev just modtaget) fra SDFE‘s nyhedsoversigtsside, hvor det er så åbenlyst tydeligt på billedindlæsningshastigheden at billederne er alt for meget større end nødvendigt.

Inspicering i browseren (f.eks. med Firefox dev-tools: F12->Network) viser da også at billedindholdet fylder 14,85 MiB ud af sidens samlede størrelse på 16,23 MiB (91,5%).

SDFE.dk nyhedsoversigtsside, billederoverførsel

Hvad værre er at billederne på denne side kun anvendes som meget små illustrationer til en række artikler, men hentes som enorme filer i opløsningen 1920×1080. Inspektion af det første billede i browserens DOM-inspektør (Firefox: F12->Inspector) afslører at browseren kun viser billedet i en opløsning på 100×56! Der går altså 1920*1080-100*56=2’068’000 (99,73%) pixels til fuldstændig spilde.

SDFE.dk digebillede, vist størrelse vs. datastørrelse

Et hurtigt forsøg med at nedskalere et enkelt billede (terminal-foo!), uden at gå ind i så avancerede emner som JPG-kompressionskvalitet eller alternative billedformater (for ikke at tale om reel billedoptimering), kan give en ide om hvor meget data der egentlig overføres unødigt ved visning af denne side:

$ wget –quiet https://sdfe.dk/media/2919562/dige-1920×1080.jpg
$ gm convert -resize 100×56 dige-1920×1080.jpg dige-100×56.jpg
$ ls -l dige-*
-rw-rw-r– 1 miki miki 17420 Apr 30 15:54 dige-100×56.jpg
-rw-rw-r– 1 miki miki 1568308 Apr 24 14:54 dige-1920×1080.jpg
$

Billedets størrelse reduceres her fra 1’568’308 bytes (1,60 MiB) til 17’420 bytes (17,01 KiB). Det er relativt en besparelse i overførselsmængden på dette billede på 8903%, vel at mærke med nøjagtigt det samme visuelle udbytte! For ikke at tale om den besparelse i hukommelsesforbrug og processeringstid der også opås ved at sidebeskuerens browser skal forholde sig til en tilsvarende mindre mængde data.

Under antagelse af at tilsvarende reduktioner kan opnås på det samlede sæt af billeder på denne side, vil overførselsbehovet kunne reduceres fra 15’206,40 KiB til 170,80 KiB. Tænk lige over det næste gang, webmaster!

Andre eksempler

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