hacking-howto: Sync with i3 (#126)

Includes:
- i3/i3#5463
- i3/i3#5464

_docs/hacking-howto

@@ -14,7 +14,7 @@ you find necessary, please do not hesitate to contact me.
 <p>
 ++++
 This document is not 100% up to date. Specifically, everything up to and
-including <<data_structures>> has been updated recently. The rest might contain
+including <<startup>> has been updated recently. The rest might contain
 outdated information.
 ++++
 </p>
@@ -34,30 +34,18 @@ Guide → Compiling a Meson project]. In case you’re unfamiliar:
 
 === Build system features
 
-* We use the +AX_ENABLE_BUILDDIR+ macro to enforce builds happening in a separate
-  directory. This is a prerequisite for the +AX_EXTEND_SRCDIR+ macro and building
-  in a separate directory is common practice anyway. In case this causes any
-  trouble when packaging i3 for your distribution, please open an issue.
+* +ninja test+ runs the i3 testsuite. See docs/testsuite for details.
 
-* +make check+ runs the i3 testsuite. See docs/testsuite for details.
+* +meson dist+ builds a release tarball and runs tests on the result.
 
-* +make distcheck+ (runs testsuite on +make dist+ result, tiny bit quicker
-  feedback cycle than waiting for the travis build to catch the issue).
+* +meson -Ddocs=true -Dmans=true+ will enable the options to build docs and
+  manpages. These options require additional dependencies that are normally not
+  required for users who just want to build i3.
 
-* +make uninstall+ (occasionally requested by users who compile from source)
-
-* +make+ will build manpages/docs by default if the tools are installed.
-  Conversely, manpages/docs are not tried to be built for users who don’t want
-  to install all these dependencies to get started hacking on i3. Manpages and
-  docs can be disabled with the +--disable-mans++ and ++--disable-docs++
-  configure options respectively.
-
-* non-release builds will enable address sanitizer by default. Use the
-  +--disable-sanitizers+ configure option to turn off all sanitizers, and see
-  +--help+ for available sanitizers.
-
-* Coverage reports are now generated using +make check-code-coverage+, which
-  requires specifying +--enable-code-coverage+ when calling configure.
+* +meson -Db_sanitize=address+ will enable the address sanitizer which is
+  disabled by default. A summary of memory leaks will be printed on program
+  exit. This can include false-positives. For other options of the +b_sanitize+
+  flag see https://mesonbuild.com/Builtin-options.html.
 
 == Pull requests
 
@@ -341,30 +329,26 @@ ensure that the operating system on which i3 is compiled has all the expected
 features, i3 comes with +include/queue.h+. On BSD systems, you can use +man
 queue(3)+. On Linux, you have to use google (or read the source).
 
-The lists used are +SLIST+ (single linked lists), +CIRCLEQ+ (circular
-queues) and +TAILQ+ (tail queues). Usually, only forward traversal is necessary,
-so an +SLIST+ works fine. If inserting elements at arbitrary positions or at
-the end of a list is necessary, a +TAILQ+ is used instead. However, for the
-windows inside a container, a +CIRCLEQ+ is necessary to go from the currently
-selected window to the window above/below.
-
-== Naming conventions
-
-There is a row of standard variables used in many events. The following names
-should be chosen for those:
+The lists used are +SLIST+ (single linked lists), +CIRCLEQ+ (circular queues)
+and +TAILQ+ (tail queues). Usually, +TAILQ+ is used which allows inserting
+elements at arbitrary positions or at the end of the list. If only forward
+traversal is necessary, an +SLIST+ can be used. +CIRCLEQ+ is used just to
+manage the X11 state of each window.
 
- * +conn+ is the xcb_connection_t
- * +event+ is the event of the particular type
- * +con+ names a container
- * +current+ is a loop variable when using +TAILQ_FOREACH+ etc.
+[[startup]]
+== Startup (src/main.c, main())
 
-== Startup (src/mainx.c, main())
+Among other things, the main() function does the following:
 
  * Establish the xcb connection
+ * Load the i3 config
  * Check for XKB extension on the separate X connection, load Xcursor
- * Check for RandR screens (with a fall-back to Xinerama)
+ * Set up EWMH hints
  * Grab the keycodes for which bindings exist
+ * Check for XRandR screens
  * Manage all existing windows
+ * Exec configured startup processes
+ * Start i3bar if configured
  * Enter the event loop
 
 == Keybindings