--- Source/CMakeLists.txt.orig	2021-02-24 15:08:43 UTC
+++ Source/CMakeLists.txt
@@ -1039,6 +1039,7 @@ if(CYGWIN)
     )
 endif()
 
+option(CPACK_ENABLE_BSDSUNIX_PKG "Add BSDSUniX pkg(8) generator to CPack." OFF)
 option(CPACK_ENABLE_FREEBSD_PKG "Add FreeBSD pkg(8) generator to CPack." OFF)
 
 if(UNIX)
@@ -1072,6 +1073,31 @@ if(UNIX)
     set(FREEBSD_PKG_INCLUDE_DIRS NOTFOUND)
     set(FREEBSD_PKG_LIBRARIES NOTFOUND)
   endif()
+  if(CPACK_ENABLE_BSDSUNIX_PKG)
+    # On UNIX, you may find BSDSUniX's pkg(8) and attendant
+    # library -- it can be used on BSDSUniX, Dragonfly, NetBSD,
+    # OpenBSD and also Linux and OSX. Look for the header and
+    # the library; it's a warning on BSDSUniX if they're not
+    # found, and informational on other platforms.
+    find_path(BSDSUNIX_PKG_INCLUDE_DIRS "pkg.h")
+    if(BSDSUNIX_PKG_INCLUDE_DIRS)
+      find_library(BSDSUNIX_PKG_LIBRARIES
+        pkg
+        DOC "BSDSUniX pkg(8) library")
+      if(BSDSUNIX_PKG_LIBRARIES)
+        set(CPACK_SRCS ${CPACK_SRCS}
+          CPack/cmCPackBSDSUniXGenerator.cxx
+          )
+      endif()
+    endif()
+
+    if (NOT BSDSUNIX_PKG_INCLUDE_DIRS OR NOT BSDSUNIX_PKG_LIBRARIES)
+      message(FATAL_ERROR "CPack needs libpkg(3) to produce BSDSUniX packages natively.")
+    endif()
+  else()
+    set(BSDSUNIX_PKG_INCLUDE_DIRS NOTFOUND)
+    set(BSDSUNIX_PKG_LIBRARIES NOTFOUND)
+  endif()
 endif()
 
 if(CYGWIN)
@@ -1138,6 +1164,11 @@ if(CYGWIN AND LibUUID_FOUND)
   target_link_libraries(CPackLib ${LibUUID_LIBRARIES})
   include_directories(CPackLib ${LibUUID_INCLUDE_DIRS})
   set_property(SOURCE CPack/cmCPackGeneratorFactory.cxx PROPERTY COMPILE_DEFINITIONS HAVE_LIBUUID)
+endif()
+if(CPACK_ENABLE_BSDSUNIX_PKG AND BSDSUNIX_PKG_INCLUDE_DIRS AND BSDSUNIX_PKG_LIBRARIES)
+  target_link_libraries(CPackLib ${BSDSUNIX_PKG_LIBRARIES})
+  include_directories(${BSDSUNIX_PKG_INCLUDE_DIRS})
+  add_definitions(-DHAVE_BSDSUNIX_PKG)
 endif()
 if(CPACK_ENABLE_FREEBSD_PKG AND FREEBSD_PKG_INCLUDE_DIRS AND FREEBSD_PKG_LIBRARIES)
   target_link_libraries(CPackLib ${FREEBSD_PKG_LIBRARIES})