cmake: some improvements

* not depending on "-dev" packages for the built Debian package
* some refactoring in if-clauses and with "quotes"
* libvterm dependency: if something is missing, made clear what

CMakeLists.txt

@@ -58,5 +58,5 @@ set(CPACK_PACKAGE_DESCRIPTION_SUMMARY "Library for a pseudo terminal where the h
 set(CPACK_DEBIAN_PACKAGE_HOMEPAGE ${CMAKE_PROJECT_HOMEPAGE_URL})
 
 set(CPACK_GENERATOR "DEB" "TGZ")
-set(CPACK_DEBIAN_PACKAGE_DEPENDS "libncursesw6 (>=6.2), libvterm-dev (>= 0.1.2)")
+set(CPACK_DEBIAN_PACKAGE_DEPENDS "libncursesw6 (>=6.2), libvterm0 (>= 0.1.2)")
 include(CPack)

cmake/gsl.cmake

@@ -3,9 +3,9 @@
 # @author Christian Burger <christian@krikkel.de>
 
 find_path(GSL_INCLUDE_DIR "gsl/gsl" REQUIRED)
-if(GSL_INCLUDE_DIR STREQUAL "GSL_INCLUDE_DIR-NOTFOUND")
+if(NOT GSL_INCLUDE_DIR)
     message(SEND_ERROR "Microsoft GSL not found.")
 else()
-    message(STATUS "Microsoft GSL found.")
+    message(STATUS "Found Microsoft C++ GSL.")
     include_directories(SYSTEM ${GSL_INCLUDE_DIR})
 endif()

cmake/libvterm.cmake

@@ -12,12 +12,20 @@
 # @author Christian Burger <christian@krikkel.de>
 
 
-find_library(LIBVTERM_LIBRARY NAMES libvterm.so.0.0.2 vterm)
+find_library(LIBVTERM_LIBRARY NAMES "libvterm.so.0.0.2" "vterm")
+find_path(LIBVTERM_INCLUDE "vterm.h")
 
-include(ExternalProject)
-
-if(LIBVTERM_LIBRARY STREQUAL "LIBVTERM_LIBRARY-NOTFOUND")
-    message(STATUS "libvterm not found — building it")
+if(NOT LIBVTERM_LIBRARY)
+    message(STATUS "Did not find `libvterm.so`.")
+    set(LIBVTERM_BUILD_IT TRUE)
+endif()
+if(NOT LIBVTERM_INCLUDE)
+    message(STATUS "Did not find `vterm.h`.")
+    set(LIBVTERM_BUILD_IT TRUE)
+endif()
+if(LIBVTERM_BUILD_IT)
+    include(ExternalProject)
+    message(STATUS "Did not find libvterm (see previous error) — building it.")
     ExternalProject_Add(
         libvtermProject
         DOWNLOAD_COMMAND URL "https://launchpad.net/ubuntu/+archive/primary/+sourcefiles/libvterm/0.1.2-2/libvterm_0.1.2.orig.tar.gz"
@@ -28,4 +36,6 @@ if(LIBVTERM_LIBRARY STREQUAL "LIBVTERM_LIBRARY-NOTFOUND")
     ExternalProject_Get_property(libvtermProject SOURCE_DIR)
     set(LIBVTERM_LIBRARY "${SOURCE_DIR}/.libs/libvterm.a")
     include_directories(SYSTEM "${SOURCE_DIR}/include")
+else()
+    message(STATUS "Found vterm library.")
 endif()

cmake/ncurses.cmake

@@ -8,8 +8,8 @@ find_package(Curses 6.2 REQUIRED)
 include_directories(SYSTEM ${CURSES_INCLUDE_DIRS})
 
 # find C++ interface for ncurses with unicode support
-find_library(CURSES_CPP_WIDE_LIBRARY NAMES ncurses++w REQUIRED)
+find_library(CURSES_CPP_WIDE_LIBRARY NAMES ncurses++w)
 if(NOT CURSES_CPP_WIDE_LIBRARY)
-    message(FATAL_ERROR "C++ interface for ncurses (wide/unicode) not found.")
+    message(SEND_ERROR "C++ interface for ncurses (wide/unicode) not found.")
 endif()
 list(APPEND CURSES_LIBRARIES ${CURSES_CPP_WIDE_LIBRARY})