| libxml2 on VxWorks 6.4+ |
| |
| Here are my instructions for building on VxWorks.... I am very ashamed of |
| how I did this because it is a complete hack, but it works great, so I |
| can't complain too much. |
| |
| General Information |
| |
| 1. The only way to build for VxWorks is to cross compile from a windows or |
| linux system. We use a RedHat 5.1 workstation system as our build |
| environment. |
| |
| 2. VxWorks 6.X has two main types of executable, DKMs (dynamic kernel |
| modules), and RTPs (real-time processes). Kernel modules are the bread |
| and butter of VxWorks, but they look nothing like processes/threads in |
| normal UNIX/Windows systems. RTPs are more like processes that have |
| memory protection, threads, etc. VxWorks 6.X also introduces some level |
| of POSIX conformance to their environment. The POSIX conformance was the |
| key for us to be able to port libxml2. We support accessing libxml2 from |
| both DKMs and RTPs. |
| |
| 3. There are 2 compilers for VxWorks, the WindRiver compiler, and a port |
| of the GNU toolchain, we have only tested and built with the GNU |
| toolchain. |
| |
| How To Build |
| |
| 1. Run the configure on your native linux system (this is the cheesy |
| hack). Since the VxWorks GNU toolchain is very close in version to the |
| one in red hat, it generates a good config.h file. We configured libxml2 |
| with the following to keep the size down, (but we have done basic testing |
| with everything compiled in). |
| |
| ./configure --with-minimum --with-reader --with-writer --with-regexps |
| --with-threads --with-thread-alloc |
| |
| 2. Rename the libxml2 folder to "src". This step is required for our |
| replacement makefile to work. |
| |
| 3. Run the replacement makefile. I wrote a new makefile that sets all the |
| proper vxworks defines and uses the correct compilers. The two defines on |
| the make command line are to tell it which VxWorks Target (SH3.2 little |
| endian), and the executable type. We have tested this code on PENTIUM2gnu |
| and SH32gnule. |
| |
| This makefile creates a shared library that runs on VxWorks: (libxml2.so) |
| make -f Makefile.vxworks clean all VXCPU=SH32gnule VXTYPE=RTP |
| |
| This makefile creates a kernel module that runs on VxWorks: (xml2.out) |
| make -f Makefile.vxworks clean all VXCPU=SH32gnule VXTYPE=DKM |
| |
| Important Notes |
| |
| 1. There are several ways that this process could be improved, but at the |
| end of the day, we make products, not port libraries, so we did a meets |
| minimum for our needs. |
| |
| 2. VxWorks is the devil, give me embedded linux every day. |
| |
| 3. No matter what I tried, I couldn't get the configure to pick up the |
| VxWorks toolchain, and in my investigation, it has something to do with |
| automake/autoconf, not any individual package. VxWorks doesn't play by |
| the normal rules for building toolchains. |
| |
| 4. The PIC flag in VxWorks (especially for SH processors) is very |
| important, and very troublesome. On linux, you can liberally use the PIC |
| flag when compiling and the compiler/linker will ignore it as needed, on |
| VxWorks if must always be on for shared libraries, and always be off for |
| static libraries and executables. |
| |
| 5. If anyone wants to work on a better way to do the build of libxml2 for |
| VxWorks, I'm happy to help as much as I can, but I'm not looking to |
| support it myself. |
| |
| Attached Files |
| |
| 1. To use my Makefile for vxworks, you should enter the vxworks |
| environment (/opt/windriver/wrenv.linux -p vxworks-6.4 for me). |
| 2. Run: build.sh libxml2-2.6.32 SH32gnule RTP (where you have |
| libxml2-2.6.32.tar.gz and the Makefile in the same directory as the script |
| file). |
| |
| Thanks, |
| |
| Jim Wert Jr. |
| JWert@ILSTechnology.com |