CMake: handle libraries' sonames

libowlps-client and libowlps-resultreader were never built as shared
libraries, therefore we set their version number to 1.0.

For stable releases, the rule is to increase the minor version number
when changes are made to the library without changing the API, and to
bump the major version number (soname) in case of API change.

In the development branch and for development point releases, the soname
should not be increased, even in case of API break. The minor version
number should be bumped instead.

Following this rule, libowlps' version number is bumped to 3.1, as some
changes were made since version 3.0.

TODO.t2t

@@ -56,7 +56,6 @@ Work to do in OwlPS
 - Add option dump-configuration (displays the config & exits).
 
 - CMake:
-  - libraries: version numbers (sonames) and symbolic links
   - installation targets
 
 - Support string-based positioning requests

libowlps-client/CMakeLists.txt

@@ -2,6 +2,10 @@ add_library(libowlps-client.a STATIC libowlps-client.c)
 add_library(libowlps-client.so SHARED libowlps-client.c)
 set_target_properties(
   libowlps-client.a libowlps-client.so
-  PROPERTIES OUTPUT_NAME owlps-client)
+  PROPERTIES
+  OUTPUT_NAME owlps-client
+  SOVERSION 1
+  VERSION 1.0
+  )
 target_link_libraries(libowlps-client.so libowlps.so)
 target_link_libraries(libowlps-client.a libowlps.a)

libowlps-resultreader/CMakeLists.txt

@@ -2,7 +2,11 @@ add_library(libowlps-resultreader.a STATIC libowlps-resultreader.c)
 add_library(libowlps-resultreader.so SHARED libowlps-resultreader.c)
 set_target_properties(
   libowlps-resultreader.a libowlps-resultreader.so
-  PROPERTIES OUTPUT_NAME owlps-resultreader)
+  PROPERTIES
+  OUTPUT_NAME owlps-resultreader
+  SOVERSION 1
+  VERSION 1.0
+  )
 target_link_libraries(libowlps-resultreader.so libowlps.so)
 target_link_libraries(libowlps-resultreader.a libowlps.a)
 

libowlps/CMakeLists.txt

@@ -2,4 +2,8 @@ add_library(libowlps.a STATIC libowlps.c)
 add_library(libowlps.so SHARED libowlps.c)
 set_target_properties(
   libowlps.a libowlps.so
-  PROPERTIES OUTPUT_NAME owlps)
+  PROPERTIES
+  OUTPUT_NAME owlps
+  SOVERSION 3
+  VERSION 3.1
+  )