From 699238f08ffd9ebf1594c5692dc965c67c290817 Mon Sep 17 00:00:00 2001
From: Peter Conrad <conrad@quisquis.de>
Date: Sat, 17 Aug 2019 10:23:15 +0200
Subject: [PATCH] Fix build with older cmake

---
 CMakeLists.txt                       |  3 ++-
 CMakeModules/Boost/BoostConfig.cmake | 18 ++++++++++++++++++
 2 files changed, 20 insertions(+), 1 deletion(-)
 create mode 100644 CMakeModules/Boost/BoostConfig.cmake

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 4394887..0966c95 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -136,7 +136,8 @@ IF( WIN32 )
   # iphlpapi.lib
 ENDIF(WIN32)
 
-FIND_PACKAGE(Boost COMPONENTS ${BOOST_COMPONENTS} REQUIRED)
+set(Boost_DIR "${CMAKE_CURRENT_SOURCE_DIR}/CMakeModules/Boost")
+FIND_PACKAGE(Boost CONFIG COMPONENTS ${BOOST_COMPONENTS} )
 
 IF(NOT WIN32)
     MESSAGE(STATUS "Configuring fc to build on Unix/Apple")
diff --git a/CMakeModules/Boost/BoostConfig.cmake b/CMakeModules/Boost/BoostConfig.cmake
new file mode 100644
index 0000000..a5e01f2
--- /dev/null
+++ b/CMakeModules/Boost/BoostConfig.cmake
@@ -0,0 +1,18 @@
+# This overrides `find_package(Boost ... CONFIG ... )` calls
+#  - calls the CMake's built-in `FindBoost.cmake` and adds `pthread` library dependency
+
+MESSAGE(STATUS "Using custom FindBoost config")
+
+find_package(Boost 1.58 REQUIRED COMPONENTS ${Boost_FIND_COMPONENTS})
+
+#  Inject `pthread` dependency to Boost if needed
+if (UNIX AND NOT CYGWIN)
+    list(FIND Boost_FIND_COMPONENTS thread _using_boost_thread)
+    if (_using_boost_thread GREATER -1)
+        find_library(BOOST_THREAD_LIBRARY NAMES pthread DOC "The threading library used by boost-thread")
+        if (BOOST_THREAD_LIBRARY)
+            MESSAGE(STATUS "Adding Boost thread lib dependency: ${BOOST_THREAD_LIBRARY}")
+            list(APPEND Boost_LIBRARIES ${BOOST_THREAD_LIBRARY})
+        endif ()
+    endif ()
+endif ()