Titan TTCN3 Notes » History » Revision 16
Revision 15 (pespin, 04/04/2018 10:54 AM) → Revision 16/31 (pespin, 04/05/2018 10:02 AM)
h1. Titan TTCN3 Notes
Some notes about developing in Titan TTCN3, specifically regarding test cases in the Osmocom universe.
h1. Building / Using test cases
h2. Dependencies
* You'll need recent enough eclipse-titan installed: 6.2.0 is working fine, 5.5.1 is too old.
** if you're using Debian packages, you might run into a compile error "The version of GCC does not match the expected version". If you do, it is suggested to use MAKEDEPEND_RUN define to workaround the issue. Alternatively you can edit @/usr/include/titan/cversion.h@ and comment out the related @#error@ line.
* You'll need a checkout/clone of @http://git.osmocom.org/osmo-ttcn3-hacks/@
h3. Titan Modules required
The @osmo-ttcn3-hacks@ depend on a variety of other TTCN-3 modules that you have to clone from their respective repositories. Each test suite contains a @gen_links.sh@ script that will generate symlinks from those cloned repositories to the local directory. If you look at @gen_links.sh@ you will see which dependencies the respective test suite has (but not their clone URLs, sorry).
For example, @sysinfo/gen_links.sh@ needs following repositories under @BASEDIR@ directory:
<pre>
git clone https://github.com/eclipse/titan.TestPorts.IPL4asp.git
git clone https://github.com/eclipse/titan.TestPorts.TELNETasp.git
git clone https://github.com/eclipse/titan.TestPorts.Common_Components.Socket-API.git
git clone https://github.com/eclipse/titan.Libraries.TCCUsefulFunctions.git
</pre>
See http://git.osmocom.org/docker-playground/tree/debian-stretch-titan/Dockerfile for a full list of dependencies
h2. Test run
For example, to run sysinfo tests do the following:
* adjust BASEDIR in sysinfo/gen_links.sh to match your environment
* adjust test configuration in sysinfo/Test.cfg if necessary
<pre>
cd sysinfo
./gen_links.sh
./regen_makefile.sh
make -j1 compile && make -j8
cd ..
./start-testsuite.sh sysinfo/Test sysinfo/Test.cfg
</pre>
See also https://git.osmocom.org/docker-playground/tree/ttcn3-nitb-sysinfo/
h3. Log files
you will receive log files in the current working directory. You can use the @ttcn3_logmerge@ tool to merge multiple log files based on their timestamps, and you can use the @ttcn3_logformat@ tool to do some human-friendly formatting of the log files. Harald often runs his test suite like:
<pre>
rm -f *.log && make -j1 compile && make -j8 && ../start-testsuite.sh MGCP_Test MGCP_Test.cfg && ttcn3_logformat *.log
</pre>
h1. Development related bits
h3. Learning TTCN3
A good set of slides about TTCN can be found in:
* http://download.eclipse.org/titan/TTCN3_Course_PartI_EclipseLicensed.pdf
* http://download.eclipse.org/titan/TTCN3_Course_PartII_EclipseLicensed.pdf
* http://www.ttcn-3.org/files/TTCN3_P.pdf
h2. Speedup local builds with ccache:
There's a patch in gerrit to use ccache if it is found in the build system, which provides a speedup factor of around x10.
Patch can be found in: https://gerrit.osmocom.org/#/c/7601/
Upstream should be contacted to request for inclusion of a flag to remove the "generated date" as a comment in the generated code, which prevents ccache to work fine out of the box (the provided gerrit patch workarounds this issue).
h2. RAW coder
A lot of the messages (GSMTAP, LAPDm, L1CTL, ...) are described using the Titan extensions to the TTCN-3 type language and the associated RAW coder.
Section 4.23 of the _Programmer's Technical Reference Guide for the TITAN TTCN-3 Toolset_ contains the description of this RAW coder
h3. FIELDORDER
This determines the order of fields within a record or set type.
In (not only) GSM specs, typically the messages are described from first field at top to the last field at the bottom, so the logical choice here is to set "FIELDORDER(msb)" as we do in the GMS_Types.ttcn and other files. However, there's one CAVEAT: In GSM 04.08 (and derived specs), Information Elements with 1/2 (4bit) length are ordered un-intitively.
Example: TS 44.018 SYSTEM INFORMATION TYPE 4:
* L1 Pseudl Length (1)
* protocol descriptor (1/2)
* skip indicator (1/2)
* Message Type (1)
which then translates to:
<pre>
type record RrHeader {
L2PseudoLength l2_plen,
uint4_t skip_indicator,
uint4_t rr_protocol_discriminator,
RrMessageType message_type
} with { variant "FIELDORDER(msb)" };
</pre>
Note the skip_indicator and rr_protocol_discriminator fields are swapped in their order compared to the spec!
