Porting To Symbian
- 1. Porting C/C++ to Symbian OS Mark Wilcox
- 2. What I’m Talking About What is Porting? Why Port to Symbian OS? Porting Aids: P.I.P.S. OpenGL ES Open C/C++ & RGA Coming Soon… How to do it – The Porting Process Common Problems (& Solutions) Examples: Easy: SoundTouch More Complex: GuiTune
- 3. What is Porting? “ Porting is the process of adapting software so that an executable program can be created for a computing environment that is different from the one for which it was originally designed.” (Wikipedia) i.e. Making software work on different hardware or operating systems.
- 4. Why Port to Symbian OS? The Marketing Reason… The Hacker’s Reason… The Geek’s Reason…
- 5. Porting Aids P.I.P.S. Is POSIX on Symbian OS OpenGL ES Open C/C++ for S60 RGA – Real-time Graphics & Audio
- 6. P.I.P.S. Is POSIX on Symbian OS POSIX – Portable Operating System Interface P.I.P.S. Libraries: 100 60 42 47 Function Coverage (%) Dynamic loading and symbol lookup libdl Thread creation and synchronization libpthread Mathematical and arithmetic APIs libm Standard C and POSIX APIs libc Functionality Library
- 7. OpenGL ES 2D & 3D graphics for embedded systems Subset of desktop OpenGL May need to switch floating-point to fixed 3D Demos:
- 8. Open C Superset of P.I.P.S. Adds support for 5 more libraries: 77 GNOME General purpose utility library libglib 86 OpenSSL OpenSSL secure sockets layer libssl 77 OpenSSL Cryptographic services for SSL, TLS, S/MIME, SSH, OpenPGP… libcrypto 100 OpenSSL Cryptography functions libcrypt 100 zlib In-memory compression and decompression functions libz Function Coverage (%) Source Functionality Library
- 9. Open C++ More useful libraries: Standard C++ programming extension for Open C Boost Smart pointers, extra containers and math-template functions Boost STLport C++ Standard Template Library STL STLport Standard C++ input/output streams IOStreams Source Functionality Library
- 10. Real-time Graphics & Audio Distributed with Open C/C++ APIs developed for porting N-Gage games Not a standard available anywhere else Can create rich UI without Symbian idioms Much more than just graphics & audio: 2D Graphics Sound Effects and Music Video Playback Timers Input Devices Cameras Lights Device Status and Capabilities Calendar Alerts/Todo Messaging
- 11. Open C/C++ & RGA Architecture
- 12. Coming Soon… Qt – cross-platform application framework OpenKODE – cross-platform native APIs Better standard C++ support on Symbian Full support for a dynamically linked STL Support for streams and locales Throwing operator new Better, though still limited, support for mixing standard C++ and Symbian C++ patterns Support for global destructors
- 13. How to do it – The Porting Process Convert build files Create a bld.inf file and MMP file(s) for the project Try to compile it Fix problems (loop until compiles) Try to run Debug and fix (loop until runs) Test Debug and fix (loop until works)
- 14. Common Problems (& Solutions) Symbian has E32Main(), while standard C/C++ uses main() Pre-Symbian OS v9.3 – add libcrt0.lib ‘glue code’ to your MMP file Symbian OS v9.3 onwards – use new target type STDEXE in the MMP file and ‘glue code’ is added automatically No functions exported from a library by default on Symbian OS Pre-Symbian OS v9.3 – add IMPORT_C to function declarations and EXPORT_C to the definitions for all exported functions Symbian OS v9.3 onwards – use new target types STDDLL or STDLIB and all functions with external linkage (non-static) are exported by default
- 15. Common Problems (& Solutions) Out of memory and/or Kern-Exec 3 panics at run-time Increase heap size via EPOCHEAPSIZE directive in the MMP file (although be aware that device memory is limited and code may need re-design and/or allocation failure checks) – default is only 1MB Increase stack size via EPOCSTACKSIZE directive in the MMP file – default is only 8KB, recommended value for Open C/C++ is 64KB
- 16. Common Problems (& Solutions) Standard library clashes for existing ports: There is an older partial implementation, developed to get a Java VM running on Symbian OS, in estlib.lib with headers in: \Epoc32\include\libc This is incompatible with P.I.P.S. & Open C/C++, the two cannot be used together. The estlib implementation will be deprecated when P.I.P.S. is considered sufficiently mature. In practice P.I.P.S. is already much better.
- 17. Examples – SoundTouch DLL SoundTouch - open source Audio Processing Library For changing: Tempo (time-stretch) – faster or slower without affecting pitch Pitch (key) – alter sound pitch or key without affecting tempo Playback rate – alters tempo and pitch simultaneously Implemented in C++, using features of libc, libm and STL Supports 16bit integer or 32bit floating-point PCM Platform-independent – runs on Windows, Mac & Linux Can perform real-time processing on 133MHz Pentium
- 18. Examples – SoundTouch DLL Very simple bld.inf file: PRJ_PLATFORMS DEFAULT PRJ_EXPORTS ..\inc\SoundTouch.h ..\inc\ FIFOSamplePipe.h ..\inc\STTypes.h PRJ_MMPFILES SoundTouch.mmp
- 19. Examples – SoundTouch DLL Fairly simple MMP file (copy most contents from Makefile) TARGET SoundTouch.dll TARGETTYPE dll UID 0x1000008D 0x0839739D CAPABILITY ReadUserData USERINCLUDE ..\inc SYSTEMINCLUDE \epoc32\include \epoc32\include\stdapis SYSTEMINCLUDE \epoc32\include\stdapis\sys SYSTEMINCLUDE \epoc32\include\stdapis\stlport SOURCEPATH ..\src SOURCE SoundTouch.cpp SoundTouchDllMain.cpp AAFilter.cpp SOURCE FIFOSampleBuffer.cpp FIRFilter.cpp SOURCE RateTransposer.cpp TDStretch.cpp LIBRARY euser.lib LIBRARY libc.lib libm.lib libstdcpp.lib
- 20. Examples – SoundTouch DLL Additional work: Make sure all the source and header files are copied into the workspace Configure for 16bit integer samples in STTypes.h Add IMPORT_C & EXPORT_C to the exported function declarations and definitions Compiling gave several errors, all with the same cause throw std::runtime_error("Illegal number of channels"); Code like this: Should compile by simply including <stdexcept> but <string> is needed as well. The string header should be included internally by <stdexcept> but it seems there is a bug in the Symbian version of STLport… With <string> included in the relevant files it compiles for all build targets.
- 21. Examples – GuiTune A more complex port of an open source guitar tuner for Linux. Converted a device driver polling architecture to use Symbian multimedia APIs
- 22. Examples – GuiTune Ported UI components from gtkmm to native Symbian controls
- 23. Examples – GuiTune Still relatively simple changes to the original code. Full details and code available from the Symbian Developer Network at: developer.symbian.com/main/documentation/porting/
- 24. Where to Find Out More P.I.P.S. wiki page: developer.symbian.com/wiki/display/pub/P.I.P.S. Forum Nokia Open C/C++ resources: www.forum.nokia.com/main/resources/technologies/openc_cpp/ Symbian Developer Network porting page: developer.symbian.com/main/documentation/porting/
- 25. Questions?