From bfc2c462f0ed194ecbc1a325b15b324d68932135 Mon Sep 17 00:00:00 2001
From: William Brawner <me@wbrawner.com>
Date: Thu, 9 Jan 2020 17:37:21 -0700
Subject: [PATCH] Improve CMake usage to handle installation and linking better

Signed-off-by: William Brawner <me@wbrawner.com>
---
 CMakeLists.txt     |  9 ++++-----
 src/CMakeLists.txt | 36 ++++++++++++++++++++++++++----------
 2 files changed, 30 insertions(+), 15 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 61e8a97..e315775 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -15,14 +15,13 @@
 # You should have received a copy of the GNU General Public License
 # along with PiHelper.  If not, see <https://www.gnu.org/licenses/>.
 
-cmake_minimum_required (VERSION 3.15.5)
-
-set(PIHELPER_VERSION 0.1.0)
+cmake_minimum_required (VERSION 3.10.2)
 
 project(
     pihelper
-    VERSION ${PIHELPER_VERSION}
+    VERSION 0.1.0
+    LANGUAGES C
     )
 
-add_subdirectory(PiHelper)
+add_subdirectory(src)
 
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index fbdc060..0e75b1d 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -63,6 +63,9 @@ if (NOT OPENSSL)
 endif()
 
 option(PIHELPER_STATIC "Build Pi-Helper as a static library" ON)
+option(PIHELPER_SHARED "Build Pi-Helper as a shared library" OFF)
+option(PIHELPER_EXECUTABLE "Build Pi-Helper as an executable" OFF)
+option(PIHELPER_DEV "Install Pi-Helper header files for development" OFF)
 
 if (PIHELPER_STATIC)
     add_library(libpihelperstatic STATIC
@@ -70,50 +73,63 @@ if (PIHELPER_STATIC)
         )
 
     set_target_properties(libpihelperstatic PROPERTIES OUTPUT_NAME "pihelper")
+    set_target_properties(libpihelperstatic PROPERTIES VERSION ${PROJECT_VERSION})
+    set_target_properties(libpihelperstatic PROPERTIES PUBLIC_HEADER pihelper.h)
 
     target_link_libraries(libpihelperstatic ${CURL})
     target_link_libraries(libpihelperstatic ${JSONC})
     target_link_libraries(libpihelperstatic ${CRYPTO})
     target_link_libraries(libpihelperstatic ${OPENSSL})
 
-    install(TARGETS libpihelperstatic )
+    install(TARGETS libpihelperstatic
+        LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
+        PUBLIC_HEADER DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}
+        )
 endif()
 
-option(PIHELPER_SHARED "Build Pi-Helper as a shared library" OFF)
-
-if (PIHELPER_SHARED)
+if (PIHELPER_SHARED OR PIHELPER_EXECUTABLE)
     add_library(libpihelpershared SHARED
         ${PIHELPER_SOURCES}
         )
 
     set_target_properties(libpihelpershared PROPERTIES OUTPUT_NAME "pihelper")
+    set_target_properties(libpihelpershared PROPERTIES VERSION ${PROJECT_VERSION})
+    set_target_properties(libpihelpershared PROPERTIES SOVERSION ${PROJECT_VERSION_MAJOR})
+    set_target_properties(libpihelpershared PROPERTIES PUBLIC_HEADER pihelper.h)
 
     target_link_libraries(libpihelpershared ${CURL})
     target_link_libraries(libpihelpershared ${JSONC})
     target_link_libraries(libpihelpershared ${CRYPTO})
     target_link_libraries(libpihelpershared ${OPENSSL})
 
-    install(TARGETS libpihelpershared)
+    install(TARGETS libpihelpershared
+        LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
+        PUBLIC_HEADER DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}
+        )
 endif()
 
-option(PIHELPER_DEV "Install Pi-Helper header files for development" OFF)
 if (PIHELPER_DEV)
     install(FILES PiHelper/pihelper.h DESTINATION "${CMAKE_INSTALL_FULL_INCLUDEDIR}/pihelper")
 endif()
 
-option(PIHELPER_EXECUTABLE "Build Pi-Helper as an executable" OFF)
-
 if (PIHELPER_EXECUTABLE)
+    set(CMAKE_INSTALL_RPATH_USE_LINK_PATH TRUE)
+    set(CMAKE_INSTALL_RPATH ${CMAKE_INSTALL_RPATH};${CMAKE_INSTALL_PREFIX}/${CMAKE_INSTALL_LIBDIR})
+
     add_executable(pihelper
-        ${PIHELPER_SOURCES}
         cli.c
         )
 
+    message("Setting RPATH to ${CMAKE_INSTALL_RPATH}")
+
+    target_link_libraries(pihelper libpihelpershared)
     target_link_libraries(pihelper ${CURL})
     target_link_libraries(pihelper ${JSONC})
     target_link_libraries(pihelper ${CRYPTO})
     target_link_libraries(pihelper ${OPENSSL})
 
-    install(TARGETS pihelper)
+    install(TARGETS pihelper
+        RUNTIME  DESTINATION ${CMAKE_INSTALL_BINDIR}
+        )
 endif()