Contributing to Linux

sudo apt install linux-source

mkdir $HOME/kernel
cd $HOME/kernel

tar -xaf /usr/src/linux-source-*.tar.*

du -sh *

apt update
apt install mint-dev-tools --install-recommends
apt install devhelp

cd ~/projects
git clone https://github.com/linuxmint/pix.git
cd pix
mint-build
# lots of:  warning: "gtk_*" is deprecated [-Wdeprecated-declarations]
# some:    warning: remember to run 'libtool --finish /usr/lib/x86_64-linux-gnu/pix/extensions'
# succeeded, and created ELF binary ./pix/pix, and also a bunch
# of installer files in .. (above the project directory !)

# replace standard with new one just built
sudo mv /usr/bin/pix /usr/bin/pix.sav
sudo cp pix/pix /usr/bin/pix

# run new one, see if it works
/usr/bin/pix

# restore back to standard version
sudo rm /usr/bin/pix
sudo mv /usr/bin/pix.sav /usr/bin/pix

cd ~/projects/pix
dpkg-buildpackage

# You're going to need probably 25 GB of free disk space

sudo apt install mercurial

cd projects
mkdir mozilla
cd mozilla
# Next line takes about 30 minutes and 8 GB of disk
hg clone https://hg.mozilla.org/mozilla-central source/
cd source
hg clone https://hg.mozilla.org/comm-central comm/

sudo apt install python3-pip

sudo apt install llvm

sudo apt install libnotify-bin

# In source dir:
./mach bootstrap
# Choose option "2. Firefox for Desktop"

# Got some notice about updating PATH.
# Log out and back in.

rustc --version
# If you're missing Rust and/or cargo:
curl https://sh.rustup.rs -sSf | sh

cbindgen --version
# If you're missing cbindgen:
cargo install cbindgen
# If cargo is not found, maybe log out so PATH gets refreshed

# In source dir:
echo 'ac_add_options --enable-application=comm/mail' >mozconfig
echo 'ac_add_options --with-app-basename=Thunderbird' >>mozconfig

cd source
./mach build	# takes a couple of hours on my slow laptop
# And I found the cooling on my laptop is dead; 3+ minutes
# of heavy compiling makes CPU core temps spike from 55C to 82C.
# Now the mozilla tree will be about 20 GB of disk space

# First couple of builds on old laptop failed; did:
./mach clobber
./mach build

# Build on new fast laptop took 22 minutes,
# temperatures around 80 - 83C.
# Now projects/mozilla totals 21 GB.
# Executable result is ./source/obj-x86_64-pc-linux-gnu/dist/bin/thunderbird ?
# It's about 8 MB, since it includes symbols.

# Maybe quit out of existing Thunderbird and back it up before doing this ?
./mach run
# or:
./source/obj-x86_64-pc-linux-gnu/dist/bin/thunderbird

# To get latest changes and build again:
# In source directory:
hg pull -u; (cd comm; hg pull -u)
./mach build

# Not sure where app is getting its config info from;
# not from my standard $HOME/.thunderbird

# run installed release version of Liferea and export feed list to a file, in case of disaster

sudo apt install libtool intltool libxml2-dev libxslt1-dev libsqlite3-dev libwebkit2gtk-4.0-dev libjson-glib-dev libgirepository1.0-dev libpeas-dev gsettings-desktop-schemas-dev

cd ~/projects
git clone https://github.com/lwindolf/liferea.git
cd liferea

./autogen.sh
# says "Liferea will be installed in /usr/local/bin"
whereis liferea
# says I have release version of Liferea in /usr/bin

make
# see lots of warnings about deprecated GTK and pango things
# big gcc line near end gave lots of assertion failures

sudo make install

/usr/bin/liferea --version
/usr/local/bin/liferea --version

/usr/local/bin/liferea

sudo apt install git cmake dialog

mkdir -p ~/kde/src
cd ~/kde/src/
git clone https://invent.kde.org/sdk/kdesrc-build.git
cd kdesrc-build

./kdesrc-build --initial-setup
source ~/.bashrc
# Check that source has worked by checking the
# new path for "~/kde/src/kdesrc-build":
echo $PATH
# https://apps.kde.org/kdesrc_build/
# https://docs.kde.org/trunk5/en/kdesrc-build/kdesrc-build/index.html

# Don't build all of Qt from source, use from distro:
# Edit ~/.config/kdesrc-buildrc so:
# qtdir
# and the lines include...qt5-build-include
# and include...custom-qt5-libs-build-include
# are commented out,
# and confirm line with kf5-qt5-build-include
# has NOT been commented out.
# Set include-dependencies to false.

# reboot VM and log back in

# Do this in home directory:
kdesrc-build akregator
# Will download source via git,
# and build into ~/kde/usr/bin/akregator

# Run the copy you built:
kdesrc-run akregator
# App runs okay but doesn't quit cleanly IF YOU Alt+F4,
# GUI closes but then command in terminal is hung.
# Quits cleanly if you File / Quit (Ctrl+Q).

# Worked fine for a week or so, then some update to
# the app source resulted in version mismatch with
# headers/libraries on the distro.  Have to wait for
# distro update ?

# Tried to change ~/.config/kdesrc-buildrc to say
# "build everything", and couldn't get it to work.

# Then a distro update came through.  Updated, got
# build system back to sanity, still have version
# mismatch problem.  Wants "KF5GrantleeTheme" 5.22.40,
# I have 5.21.40.  Another distro update came through,
# still dead.

# Sent an email to mailing list, asking
# for help.  Got a DMARC failure, not sure on which end.

# AKREGATOR_LOG is a Qt "logging category" ?
# https://www.qt.io/blog/2014/03/11/qt-weekly-1-categorized-logging

# There is ~/.config/QtProject.conf
# https://stackoverflow.com/questions/17305374/qt-5-0-built-in-logging

# Default, logging goes to console.  Send to log file with:
#    kdesrc-run akregator 2>log.txt
# If I add a statement:
#    qCInfo(AKREGATOR_LOG) << "in main.";
# on console I see:
#    org.kde.pim.akregator: in main.
# So by default, logging at the "info" level is enabled.
# Same if I use qCWarning(); no indication of level of message.

# Some messages are coming from outside the application.

# There are qCDebug() qCInfo() qCWarning() qCCritical()
# qCFatal() from <cassert> ?
# There are qDebug() qInfo() qWarning() qCritical()
# qFatal() from <QtGlobal> or <QDebug> ?

# There is a way to log to system journal or system log:
# https://www.ics.com/blog/whats-new-qt-560-logging-syslog-and-journald
# but what is the "configure script" it talks about ?

cd ~/kde/build/akregator/
source ./prefix.sh
ctest --show-only
ctest --verbose
ctest --output-on-failure

folder.cpp:
  Folder
    articles() gives all articles in all feeds in the folder ?
    children()
feed/feedlist.cpp:
  FeedList contains:
    Storage *storage
    list of TreeNode flatList
    visitFolder()
    constructor creates the folder "All Feeds"
    feedIds() gives list of feed IDs
    folders() gives list of folders in the FeedList
feed/feed.cpp:
  Feed contains:
    ArchiveMode m_archiveMode
    list of articles
    appendArticles() does something with removing from archive
storage/feedstorage.cpp:
  FeedStorage contains:
    c4_Storage *storage;
      Storage *mainStorage;
      c4_View archiveView;
    articles() gives list of articles
storage/storage.cpp
  Storage:
    knows file path to archive
    opens index files archiveindex.mk4 and feedlistbackup.mk4
    rest of files in Archive are individual feeds, named URL.mk4
    all files are binary format
    feeds() gives list of feeds (URLs)
article.cpp
  Article:
    Status bits: Deleted Trash New Read Keep (can be multiple)

"action manager": sets up GUI and connects it to internals ?
"commands": come from "actions" and open GUI dialogs etc ?

Akregator app is a "Part" in the KDE PIM framework.
Exposed methods: org.kde.akregator.part.xml

Asynchronous operations are done via "slots" and "jobs" (KJob, QTimer) ?

Contributing to Linux

Overview

Linux Development

Kernel Development

Driver / Kernel Module Development

Linux Application Development

Make a New Distro

Miscellaneous