genode/repos/libports
Norman Feske a99f6a81b6 libc: clone 'environ' pointer value after fork
The 'environ' pointer is a global variable that must be considered as
part of the application state. It must be copied from the parent to the
child process during fork. Otherwise, a child returning from fork is
unable to access environment variables before invoking execve. The
actual environment variables and their values are already captured
because they reside at the application heap, which is cloned from the
parent. So the copied 'environ' pointer refers to valid data.

Fixes #4015
2021-02-23 12:02:44 +01:00
..
doc tool: remove deprecated 'make prepare' mechanism 2016-03-17 17:02:04 +01:00
include libgmp: avoid undefined gmpn_*_2 symbols (x86_64) 2021-02-23 12:02:42 +01:00
lib qt5: improve quickcontrols2 module support 2020-12-18 09:11:25 +01:00
ports qt5: improve quickcontrols2 module support 2020-12-18 09:11:25 +01:00
recipes libc: clone 'environ' pointer value after fork 2021-02-23 12:02:44 +01:00
run Remove support for the Muen separation kernel 2021-02-23 11:55:44 +01:00
src libc: clone 'environ' pointer value after fork 2021-02-23 12:02:44 +01:00
README README update 2016-08-30 17:24:00 +02:00

This directory contains ports of popular 3rd-party software to Genode.


Usage
-----

The tool './tool/ports/prepare_port' in the toplevel directory automates the
task of downloading and preparing the library source codes. You can select
individual packages that have to be prepared by specifying their base names
(without the version number) as command-line argument. For example, the
following command prepares both the C library and the Freetype library:
! ./tool/ports/prepare_port libc freetype

To compile and link against 3rd-party libraries of the 'libports' repository,
you have to include the repository into the build process by appending it to the
'REPOSITORIES' declaration of your '<build-dir>/etc/build.conf' file.


Under the hood
--------------

For each library, there is a file contained in the 'libports/ports/'
subdirectory. The file is named after the library and contains the
library-specific rules for downloading the source code and installing header
files.


How does 'libports' relate to the other repositories?
-----------------------------------------------------

Most libraries hosted in the 'libports' repository expect a complete C library,
which is provided with the 'libc' package. Please do not forget to prepare the
libc package when using any of the other libports packages. The libc, in turn,
depends on the 'os' repository for its back end. Because the 'os' repository is
the home of the dynamic linker, libraries contained in 'libports' are safe to
assume the presence of the dynamic linker and, thus, should be built as shared
libraries.