Modernize CMake build.

* CMakeLists.txt, builds/cmake/FindHarfBuzz.cmake: Extensive
  modernization measures.

* .gitignore: Add build/, as that's the example directory used in
  CMakeLists.txt.

This brings up the minimum required CMake version to 2.8.12.

The installation paths follow the GNU defaults now, e.g. installing on a
64 bit host will place binaries into the lib64/ folder on e.g. Fedora.

Symbols are hidden by default (e.g. `-fvisibility=hidden' on GCC).

CMake will no longer look for a C++ compiler.

Library and .so version now match the Autotools build.

Comments in the build file and informational messages now use platform
agnostic example commands.

ftoption.h and ftconfig.h are written directly without a redundant
`-new' copy.

External dependencies are expressed as option()s and will turn up as
such in cmake-gui.

Internal: Properties such as dependencies and include directories are
now privately set on the freetype library instead of globally.

The CPack definitions have been cleaned up, the `make dist' has been
removed. Source packages generated with CPack don't contain Autotools
files and aren't used by the maintainters anyway.

On Windows, src/base/ftver.rc is compiled to decorate the library with
version and copyright information.

A pkg-config file is now generated and installed.

1 files changed, 33 insertions, 24 deletions

diff --git a/builds/cmake/FindHarfBuzz.cmake b/builds/cmake/FindHarfBuzz.cmake
index f394b82bf..ee0d52e36 100644
--- a/builds/cmake/FindHarfBuzz.cmake
+++ b/builds/cmake/FindHarfBuzz.cmake
@@ -31,42 +31,51 @@
 # HARFBUZZ_LIBRARIES - containg the HarfBuzz library
 
 include(FindPkgConfig)
+pkg_check_modules(PC_HARFBUZZ QUIET harfbuzz)
 
-pkg_check_modules(PC_HARFBUZZ harfbuzz>=0.9.7)
-
-find_path(HARFBUZZ_INCLUDE_DIRS NAMES hb.h
-    HINTS ${PC_HARFBUZZ_INCLUDE_DIRS} ${PC_HARFBUZZ_INCLUDEDIR}
+find_path(HARFBUZZ_INCLUDE_DIRS
+    NAMES hb.h
+    HINTS ${PC_HARFBUZZ_INCLUDEDIR}
+          ${PC_HARFBUZZ_INCLUDE_DIRS}
+    PATH_SUFFIXES harfbuzz
 )
 
 find_library(HARFBUZZ_LIBRARIES NAMES harfbuzz
-    HINTS ${PC_HARFBUZZ_LIBRARY_DIRS} ${PC_HARFBUZZ_LIBDIR}
+    HINTS ${PC_HARFBUZZ_LIBDIR}
+          ${PC_HARFBUZZ_LIBRARY_DIRS}
 )
 
-# HarfBuzz 0.9.18 split ICU support into a separate harfbuzz-icu library.
-if ("${PC_HARFBUZZ_VERSION}" VERSION_GREATER "0.9.17")
-    if (HarfBuzz_FIND_REQUIRED)
-        set(_HARFBUZZ_REQUIRED REQUIRED)
-    else ()
-        set(_HARFBUZZ_REQUIRED "")
-    endif ()
-    pkg_check_modules(PC_HARFBUZZ_ICU harfbuzz-icu>=0.9.18 ${_HARFBUZZ_REQUIRED})
-    find_library(HARFBUZZ_ICU_LIBRARIES NAMES harfbuzz-icu
-        HINTS ${PC_HARFBUZZ_ICU_LIBRARY_DIRS} ${PC_HARFBUZZ_ICU_LIBDIR}
-    )
-    if (HARFBUZZ_ICU_LIBRARIES)
-        list(APPEND HARFBUZZ_LIBRARIES "${HARFBUZZ_ICU_LIBRARIES}")
+if (HARFBUZZ_INCLUDE_DIRS)
+    if (EXISTS "${HARFBUZZ_INCLUDE_DIRS}/hb-version.h")
+        file(READ "${HARFBUZZ_INCLUDE_DIRS}/hb-version.h" _harfbuzz_version_content)
+
+        string(REGEX MATCH "#define +HB_VERSION_STRING +\"([0-9]+\\.[0-9]+\\.[0-9]+)\"" _dummy "${_harfbuzz_version_content}")
+        set(HARFBUZZ_VERSION "${CMAKE_MATCH_1}")
     endif ()
-    set(_HARFBUZZ_EXTRA_REQUIRED_VAR "HARFBUZZ_ICU_LIBRARIES")
-else ()
-    set(_HARFBUZZ_EXTRA_REQUIRED_VAR "")
+endif ()
+
+if ("${harfbuzz_FIND_VERSION}" VERSION_GREATER "${HARFBUZZ_VERSION}")
+    message(FATAL_ERROR "Required version (" ${harfbuzz_FIND_VERSION} ") is higher than found version (" ${HARFBUZZ_VERSION} ")")
 endif ()
 
 include(FindPackageHandleStandardArgs)
-FIND_PACKAGE_HANDLE_STANDARD_ARGS(HarfBuzz DEFAULT_MSG HARFBUZZ_INCLUDE_DIRS
-    HARFBUZZ_LIBRARIES ${_HARFBUZZ_EXTRA_REQUIRED_VAR})
+FIND_PACKAGE_HANDLE_STANDARD_ARGS(
+    harfbuzz 
+        REQUIRED_VARS HARFBUZZ_INCLUDE_DIRS HARFBUZZ_LIBRARIES
+        VERSION_VAR HARFBUZZ_VERSION)
 
 mark_as_advanced(
-    HARFBUZZ_ICU_LIBRARIES
     HARFBUZZ_INCLUDE_DIRS
     HARFBUZZ_LIBRARIES
 )
+
+# Allows easy linking as in 
+#   target_link_libraries(freetype PRIVATE Harfbuzz::Harfbuzz)
+if (NOT CMAKE_VERSION VERSION_LESS 3.1)
+    if (HARFBUZZ_FOUND AND NOT TARGET Harfbuzz::Harfbuzz)
+        add_library(Harfbuzz::Harfbuzz INTERFACE IMPORTED)
+        set_target_properties(
+            Harfbuzz::Harfbuzz PROPERTIES
+                INTERFACE_INCLUDE_DIRECTORIES "${HARFBUZZ_INCLUDE_DIRS}")
+    endif ()
+endif ()