CMake: test for the presence of Confuse

CMakeLists.txt

@@ -18,13 +18,21 @@ include_directories("${GENERATED_INCLUDE}")
 # Note: we test here the dependencies relevant for more than one module;
 # other tests are done in each module's directory.
 
+# Add cmake/Modules to the molude path so that CMake can find the
+# additional FindXXX modules we (unfortunately have to) ship
+set(CMAKE_MODULE_PATH
+  ${CMAKE_MODULE_PATH} "${CMAKE_SOURCE_DIR}/cmake/Modules")
+
 # Check if we've got POSIX threads
 set(CMAKE_THREAD_PREFER_PTHREAD on)
 find_package(Threads)
 if (CMAKE_THREAD_LIBS_INIT AND CMAKE_USE_PTHREADS_INIT)
-  set(HAVE_PTHREADS on)
+  set(HAVE_PTHREADS true)
 endif()
 
+# Check if we've got the Confuse library
+find_package(Confuse)
+
 
 ### OwlPS' version ###
 
@@ -120,15 +128,28 @@ include_directories(libowlps-resultreader)
 
 ### Programs targets ###
 
-if (HAVE_PTHREADS)
+## Aggregator ##
+
+if (HAVE_PTHREADS AND CONFUSE_FOUND)
   add_subdirectory(owlps-aggregator)
-else()
-  message(WARNING
-    "POSIX threads are not available, OwlPS Aggregator will not be built")
+
+else() # Warn the user about missing dependencies
+  if (NOT HAVE_PTHREADS)
+    message(WARNING
+      "OwlPS Aggregator dependency missing: POSIX threads")
+  endif()
+  if (NOT CONFUSE_FOUND)
+    message(WARNING
+      "OwlPS Aggregator dependency missing: libConfuse")
+  endif()
 endif()
 
+## Client ##
+
 add_subdirectory(owlps-client)
 
+## Listener ##
+
 if (${CMAKE_SYSTEM_NAME} STREQUAL Linux)
   add_subdirectory(owlps-listener)
 else()
@@ -136,6 +157,8 @@ else()
     "OwlPS Listener can be built only for Linux systems")
 endif()
 
+## Positioner ##
+
 # OwlPS Positioner can be built only with GCC, and with a minimal
 # version. CMAKE_CXX_COMPILER_VERSION is not guaranteed to be set,
 # so we will test GCC's version number only if possible.
@@ -158,11 +181,14 @@ else() # we're not using GCC
     "OwlPS Positioner requires GCC (>= ${POSITIONER_MIN_GCC_VERSION})")
 endif()
 
+## UDP-to-HTTP ##
+
 if (HAVE_PTHREADS)
   add_subdirectory(owlps-udp-to-http)
-else()
+
+else() # Warn the user about missing dependencies
   message(WARNING
-    "POSIX threads are not available, OwlPS UDP-to-HTTP will not be built")
+    "OwlPS UDP-to-HTTP dependency missing: POSIX threads")
 endif()
 
 

cmake/Modules/FindConfuse.cmake

@@ -0,0 +1,17 @@
+# This module tries to find the Confuse library and sets the following
+# variables:
+#   CONFUSE_INCLUDE_DIR
+#   CONFUSE_LIBRARY
+#   CONFUSE_FOUND
+
+# Search for the header file
+find_path(CONFUSE_INCLUDE_DIR confuse.h
+  PATH_SUFFIXES include)
+
+# Search for the library
+find_library(CONFUSE_LIBRARY confuse
+  PATH_SUFFIXES lib)
+
+# Did we find everything we need?
+FIND_PACKAGE_HANDLE_STANDARD_ARGS(Confuse DEFAULT_MSG
+  CONFUSE_LIBRARY CONFUSE_INCLUDE_DIR)

owlps-aggregator/CMakeLists.txt

@@ -1,4 +1,5 @@
-set(EXTRA_LIBS ${EXTRA_LIBS} ${CMAKE_THREAD_LIBS_INIT} confuse)
+include_directories(${CONFUSE_INCLUDE_DIR})
+set(EXTRA_LIBS ${EXTRA_LIBS} ${CMAKE_THREAD_LIBS_INIT} ${CONFUSE_LIBRARY})
 
 add_executable(owlps-aggregatord owlps-aggregatord.c)
 target_link_libraries(owlps-aggregatord

owlps-listener/CMakeLists.txt

@@ -22,7 +22,15 @@ configure_file(
 set(EXTRA_LIBS ${EXTRA_LIBS} pcap)
 
 if (OWLPS_LISTENER_USES_CONFIG_FILE)
-  set(EXTRA_LIBS ${EXTRA_LIBS} confuse)
+  if (CONFUSE_FOUND)
+    include_directories(${CONFUSE_INCLUDE_DIR})
+    set(EXTRA_LIBS ${EXTRA_LIBS} ${CONFUSE_LIBRARY})
+  else()
+    message(WARNING
+      "Confuse is not available: disabling OWLPS_LISTENER_USES_CONFIG_FILE")
+    set(OWLPS_LISTENER_USES_CONFIG_FILE off CACHE BOOL
+      "No libConfuse: disable OWLPS_LISTENER_USES_CONFIG_FILE" FORCE)
+  endif()
 endif()
 
 if (OWLPS_LISTENER_USES_PTHREAD)