Re: [Trustedjava-support] How does icedtea-minimal differ from upstream?

[Martin P. <Mar...@ia...>]

Have a nice Monday morning....

Maurice van der Pot wrote:
> I read in the instructions on building a reduced trusted java
> compartment that the icedtea-minimal tarball provides "a custom version
> of IcedTea 1.7 which is able to run on the uClibc system library and has
> a reduced dependency set."
> 
> Do you have some more information about what was changed?

In order to achieve the small JRE footprint we removed all unneeded
functionality for a server service, e.g:
- all graphics
- all sound
- all printing
- XML support
- ...

> Does the reduced dependency set translate into reduced functionality of the JRE?

Yes, sure.

> Have these changes been merged upstream?

No, this was an experimental proof-of-concept effort.

> I'm trying to get an idea of
> how much work it would be to switch to a later version of icedtea or
> openjdk.

After release of the prototype we no longer tracked development of IcedTea.
The work required would depend mostly on how many changes occurred in
the OpenJDK directory structure and build system (make vs. ant, etc.).


If your main interest is the uClibc port then you would need
the libc detection in configure.ac, passing of @TARGET_LIBC@ in
Makefile.am and these patches:
  icedtea-j2se-uclibc.patch
  icedtea-hotspot-no-glibc.patch

In addition, uClibc needs the pthread_getstack_np function which you can
find in
usr/local/portage/sys-libs/uclibc/files/uclibc-0.9.28.3-pthread_getstack_np.patch
inside the gentoo-config tarball.

If in the meantime a newer version of uClibc got support for
pthread_getattr_np - which is the normal way for the VM to get to the
stack - you can skip the Hotspot patch.

Finally, a libstdc++ built against uClibc is needed, for which the gcc
uclibc patchset had to be modified.


HTH,
Martin