[Cmake] Question about shared library versioning

[Brian Bassett]

Andy:

Thanks for the quick reply.  The main problem with this is that it fails
to set the libraries' soname.  Right now, the ADD_LIBRARY call will
generate the following call:

gcc -fPIC   -shared -o libnjs.so ${NJS_SRCS}

whereas, I need something like:

gcc -fPIC -shared -Wl,-soname=libnjs.so.${NJSVERSION_MAJOR} -o libnjs.so
${NJS_SRCS}

Is something like this possible?

Thanks.

Brian

On Thu, 2003-03-27 at 11:16, Andy Cedilnik wrote:
> Hi Brian,
> 
> Here is an example, but it may not be what you want:
> 
> # Version of library
> SET(NJSVERSION_MAJOR 0)
> SET(NJSVERSION_MINOR 1)
> SET(NJSVERSION_PATCH 0)
> 
> # Create library
> ADD_LIBRARY(njs ${NJS_SRCS})
> 
> # This will only work on unix
> IF(UNIX)
>   # Get library name
>   SET(lib
> ${CMAKE_SHARED_MODULE_PREFIX}njs${CMAKE_SHARED_MODULE_SUFFIX})  
> 
>   # Get the path to the library
>   IF(EXECUTABLE_OUTPUT_PATH)
>     SET(lib ${EXECUTABLE_OUTPUT_PATH}/${lib})
>   ELSE(EXECUTABLE_OUTPUT_PATH)
>     SET(lib ${CMAKE_CURRENT_OUTPUT_PATH}/${lib})
>   ENDIF(EXECUTABLE_OUTPUT_PATH)
> 
>   # Add custom command for making softlink
>   ADD_CUSTOM_COMMAND(
>     SOURCE njs
>     TARGET njs
>     COMMAND ln
>     ARGS -s ${lib} ${lib}.${NJSVERSION_MAJOR})
>   ADD_CUSTOM_COMMAND(
>     SOURCE njs
>     TARGET njs
>     COMMAND ln
>     ARGS -s ${lib} ${lib}.${NJSVERSION_MAJOR}.${NJSVERSION_MINOR})
>   ADD_CUSTOM_COMMAND(
>     SOURCE njs
>     TARGET njs
>     COMMAND ln
>     ARGS -s ${lib}
> ${lib}.${NJSVERSION_MAJOR}.${NJSVERSION_MINOR}.${NJSVERSION_PATCH})
> ENDIF(UNIX)
> 
> 			Andy
> 
> On Thu, 2003-03-27 at 14:03, Brian Bassett wrote:
> > Hello, 
> > 
> > I am looking at converting a project from the autoconf/automake/libtool
> > trio to CMake and have noticed what appears to be a rather large
> > deficiency in CMake.  It appears to be impossible to specify an soname
> > for the UNIX dynamic linker or any kind of versioning info (i.e. for
> > when a binary-incompatible change is made between two releases).  I have
> > been able to specify this kind of thing with libtool's --version-info
> > flag.
> > 
> > Right now, I simply get a "libnjs.so" with no soname when I set up an
> > ADD_LIBRARY line in the CMakeLists.txt file.  What I'm after is
> > something more like what libtool outputs:
> > 
> > lrwxrwxrwx    1 brian    brian          15 Dec  6 13:40 libnjs.so ->
> > libnjs.so.0.1.0
> > lrwxrwxrwx    1 brian    brian          15 Dec  6 13:40 libnjs.so.0 ->
> > libnjs.so.0.1.0
> > -rwxr-xr-x    1 brian    brian      800719 Feb 15  2001 libnjs.so.0.1.0
> > 
> > (It's not even necessary to have the third level (i.e. the .so.0.1.0);
> > the .so -> .so.0 link and the library libnjs.so.0 linked with an soname 
> > of libnjs.so.0 would suit my purposes enough to switch to CMake.)
> > 
> > I realize that all this is not possible for all platforms that CMake
> > supports (Windows comes to mind).  It might be nice to be able to encode
> > this information into the name of the dll file, for instance.