Simulate autotools behaviour in SO-NAME and symlink generation.

[coldtobi]

This patch aligns cmake so that the SONAME and library name matches the output of autotools:

With autotools: (build and then make install DESTDIR=sometmpdir)

tobi@isildor:~/workspace/deb/packages/log4cplus/upstream/log4cplus/build/tmp/usr/local/lib$ ls -la 
insgesamt 21448
drwxr-xr-x 3 tobi tobi     4096 28. Okt 18:08 .
drwxr-xr-x 4 tobi tobi     4096 28. Okt 18:08 ..
lrwxrwxrwx 1 tobi tobi       25 28. Okt 18:08 liblog4cplus-3.0.so.0 -> liblog4cplus-3.0.so.0.0.0
-rwxr-xr-x 1 tobi tobi 10671368 28. Okt 18:08 liblog4cplus-3.0.so.0.0.0
-rwxr-xr-x 1 tobi tobi      967 28. Okt 18:08 liblog4cplus.la
lrwxrwxrwx 1 tobi tobi       25 28. Okt 18:08 liblog4cplus.so -> liblog4cplus-3.0.so.0.0.0
drwxr-xr-x 2 tobi tobi     4096 28. Okt 18:08 pkgconfig

(the unicode flavour libs has been removed from above ls to illustrate the point better)

With CMake: (build and then make install DESTDIR=sometmpdir)

tobi@isildor:~/workspace/deb/packages/log4cplus/upstream/log4cplus/build_cmake/tmp/usr/local/lib$ ls -lah
insgesamt 6,4M
drwxr-xr-x 3 tobi tobi 4,0K 28. Okt 18:14 .
drwxr-xr-x 5 tobi tobi 4,0K 28. Okt 18:14 ..
drwxr-xr-x 3 tobi tobi 4,0K 28. Okt 18:14 cmake
lrwxrwxrwx 1 tobi tobi   21 28. Okt 18:14 liblog4cplus-3.0.so -> liblog4cplus-3.0.so.3
-rw-r--r-- 1 tobi tobi 6,4M 28. Okt 18:13 liblog4cplus-3.0.so.0.0.0
lrwxrwxrwx 1 tobi tobi   25 28. Okt 18:14 liblog4cplus-3.0.so.3 -> liblog4cplus-3.0.so.0.0.0

Please note that there is still one discrepancy: Autotools generates a SO-Version of zero (as configured in configure.ac) and CMake does a SO-Version of 3 (as you recently changed in wilx@aa1a04c) I left this to you to decide whether it sould be "zero" or "three", but it should be aligned.

Thanks!

[wilx]

This will not work with many platforms.

[coldtobi]

right, this should be wrapped in some if(LINUX) or like…