Fix build examples using find_package (#324)

* fix: build examples using find_package

* fix: set system definition in package file

PackageConfig.cmake.in

@@ -26,3 +26,24 @@ if(NOT ("@IMPLIB@" STREQUAL ""))
     set_property(TARGET __zenohpico_lib PROPERTY IMPORTED_IMPLIB "@CMAKE_INSTALL_PREFIX@/@CMAKE_INSTALL_LIBDIR@/@IMPLIB@")
 endif()
 target_include_directories(__zenohpico_lib INTERFACE "@CMAKE_INSTALL_PREFIX@/@CMAKE_INSTALL_INCLUDEDIR@")
+
+if(CMAKE_SYSTEM_NAME MATCHES "Linux")
+  add_compile_definitions(ZENOH_LINUX)
+elseif(POSIX_COMPATIBLE)
+  add_compile_definitions(ZENOH_LINUX)
+elseif(CMAKE_SYSTEM_NAME MATCHES "BSD")
+  add_compile_definitions(ZENOH_BSD)
+elseif(CMAKE_SYSTEM_NAME MATCHES "Darwin")
+  add_compile_definitions(ZENOH_MACOS)
+elseif(CMAKE_SYSTEM_NAME MATCHES "Emscripten")
+  add_compile_definitions(EMSCRIPTEN)
+elseif(CMAKE_SYSTEM_NAME MATCHES "Windows")
+  add_compile_definitions(ZENOH_WINDOWS)
+elseif(CMAKE_SYSTEM_NAME MATCHES "Generic")
+  if(WITH_ZEPHYR)
+    add_compile_definitions(ZENOH_ZEPHYR)
+  elseif(WITH_FREERTOS_PLUS_TCP)
+    add_compile_definitions(ZENOH_FREERTOS_PLUS_TCP)
+  endif()
+endif()
+

examples/CMakeLists.txt

@@ -4,7 +4,7 @@ if(${CMAKE_SOURCE_DIR} STREQUAL ${CMAKE_CURRENT_SOURCE_DIR})
     project(zenohpico_examples LANGUAGES C)
     include(../cmake/helpers.cmake)
     set_default_build_type(Release)
-    configure_include_project(ZENOHPICO zenohpico zenohpico ".." zenohc "https://github.com/eclipse-zenoh/zenoh-pico" "")
+    configure_include_project(ZENOHPICO zenohpico zenohpico::static ".." zenohpico "https://github.com/eclipse-zenoh/zenoh-pico" "")
     add_custom_target(examples ALL)
 else()
     message(STATUS "zenoh-pico examples")