genode/repos/gems
Norman Feske 4da52517c1 Simpify startup of dynamically linked binaries
This patch removes the component_entry_point library, which used to
proved a hook for the libc to intercept the call of the
'Component::construct' function. The mechansim has several shortcomings
(see the discussion in the associated issue) and was complex. So we
eventually discarded the approach in favor of the explicit handling of
the startup.

A regular Genode component provides a 'Component::construct' function,
which is determined by the dynamic linker via a symbol lookup.
For the time being, the dynamic linker falls back to looking up a 'main'
function if no 'Component::construct' function could be found.

The libc provides an implementation of 'Component::construct', which
sets up the libc's task handling and finally call the function
'Libc::Component::construct' from the context of the appllication task.
This function is expected to be provided by the libc-using application.
Consequently, Genode components that use the libc have to implement the
'Libc::Component::construct' function.

The new 'posix' library provides an implementation of
'Libc::Component::construct' that calls a main function. Hence, POSIX
programs that merely use the POSIX API merely have to add 'posix' to the
'LIBS' declaration in their 'target.mk' file. Their execution starts at
'main'.

Issue #2199
2017-01-13 13:06:52 +01:00
..
include Build dynamically linked executables by default 2016-12-14 11:22:27 +01:00
lib/mk gems: move reusable code to include/gems 2014-10-13 15:21:53 +02:00
run Build dynamically linked executables by default 2016-12-14 11:22:27 +01:00
src Simpify startup of dynamically linked binaries 2017-01-13 13:06:52 +01:00
README Remove repos/qt4, fix #1451 2015-03-19 08:57:20 +01:00

This directory is a source-code repository containing Genode-specific
services and applications. In contrast to the components that come with
the 'os' repository, programs contained in 'gems' are able to leverage
the functionalities provided by higher-level repositories such as 'libports'.
To use the 'gems' repository, make sure to also add those repositories to your
build configuraion.