[cmake] Generate pkg-config .pc files

CMakeLists.txt

@@ -1,4 +1,4 @@
-cmake_minimum_required(VERSION 3.1)
+cmake_minimum_required(VERSION 3.12)
 project(harfbuzz)
 
 message(WARN "HarfBuzz has a Meson port and tries to migrate all the other build systems to it, please consider using it as we might remove our cmake port soon.")
@@ -107,12 +107,17 @@ if (${HAVE_STDBOOL_H})
   add_definitions(-DHAVE_STDBOOL_H)
 endif ()
 
+# These will be used while making pkg-config .pc files
+set(PC_REQUIRES_PRIV "")
+set(PC_LIBS_PRIV "")
+
 if (NOT MSVC)
   set(THREADS_PREFER_PTHREAD_FLAG ON)
   find_package(Threads)
   if (CMAKE_USE_PTHREADS_INIT)
     add_definitions("-DHAVE_PTHREAD")
     list(APPEND THIRD_PARTY_LIBS Threads::Threads)
+    list(APPEND PC_LIBS_PRIV -pthread)
   endif ()
 endif ()
 
@@ -208,6 +213,10 @@ if (HB_HAVE_FREETYPE AND NOT TARGET freetype)
   check_funcs(FT_Get_Var_Blend_Coordinates FT_Set_Var_Blend_Coordinates FT_Done_MM_Var)
 endif ()
 
+if (HB_HAVE_FREETYPE)
+  list(APPEND PC_REQUIRES_PRIV "freetype2 >= 12.0.6")
+endif ()
+
 if (HB_HAVE_GRAPHITE2)
   add_definitions(-DHAVE_GRAPHITE2)
 
@@ -220,6 +229,8 @@ if (HB_HAVE_GRAPHITE2)
 
   list(APPEND THIRD_PARTY_LIBS ${GRAPHITE2_LIBRARY})
 
+  list(APPEND PC_REQUIRES_PRIV "graphite2 >= 1.2.0")
+
   mark_as_advanced(GRAPHITE2_INCLUDE_DIR GRAPHITE2_LIBRARY)
 endif ()
 
@@ -240,6 +251,8 @@ if (HB_HAVE_GLIB)
 
   list(APPEND THIRD_PARTY_LIBS ${GLIB_LIBRARIES})
 
+  list(APPEND PC_REQUIRES_PRIV "glib-2.0 >= 2.19.1")
+
   mark_as_advanced(GLIB_LIBRARIES GLIBCONFIG_INCLUDE_DIR GLIB_INCLUDE_DIR)
 endif ()
 
@@ -272,24 +285,28 @@ if (APPLE AND HB_HAVE_CORETEXT)
     find_library(COREFOUNDATION CoreFoundation)
     if (COREFOUNDATION)
       list(APPEND THIRD_PARTY_LIBS ${COREFOUNDATION})
+      list(APPEND PC_LIBS_PRIV "-framework CoreFoundation")
     endif ()
     mark_as_advanced(COREFOUNDATION)
 
     find_library(CORETEXT CoreText)
     if (CORETEXT)
       list(APPEND THIRD_PARTY_LIBS ${CORETEXT})
+      list(APPEND PC_LIBS_PRIV "-framework CoreText")
     endif ()
     mark_as_advanced(CORETEXT)
 
     find_library(COREGRAPHICS CoreGraphics)
     if (COREGRAPHICS)
       list(APPEND THIRD_PARTY_LIBS ${COREGRAPHICS})
+      list(APPEND PC_LIBS_PRIV "-framework CoreGraphics")
     endif ()
     mark_as_advanced(COREGRAPHICS)
   else ()
     find_library(APPLICATION_SERVICES_FRAMEWORK ApplicationServices)
     if (APPLICATION_SERVICES_FRAMEWORK)
       list(APPEND THIRD_PARTY_LIBS ${APPLICATION_SERVICES_FRAMEWORK})
+      list(APPEND PC_LIBS_PRIV "-framework ApplicationServices")
     endif ()
 
     mark_as_advanced(APPLICATION_SERVICES_FRAMEWORK)
@@ -300,12 +317,14 @@ if (WIN32 AND HB_HAVE_GDI)
   add_definitions(-DHAVE_GDI)
   list(APPEND project_headers ${PROJECT_SOURCE_DIR}/src/hb-gdi.h)
   list(APPEND THIRD_PARTY_LIBS gdi32)
+  list(APPEND PC_LIBS_PRIV -lgdi32)
 endif ()
 
 if (WIN32 AND HB_HAVE_UNISCRIBE)
   add_definitions(-DHAVE_UNISCRIBE)
   list(APPEND project_headers ${PROJECT_SOURCE_DIR}/src/hb-uniscribe.h)
   list(APPEND THIRD_PARTY_LIBS usp10 gdi32 rpcrt4)
+  list(APPEND PC_LIBS_PRIV -lusp10 -lgdi32 -lrpcrt4)
 endif ()
 
 if (WIN32 AND HB_HAVE_DIRECTWRITE)
@@ -701,6 +720,44 @@ if (NOT SKIP_INSTALL_HEADERS AND NOT SKIP_INSTALL_ALL)
   endif ()
 endif ()
 
+# get these variables in the required format
+list(REMOVE_DUPLICATES PC_REQUIRES_PRIV)
+string(REPLACE ";" ", " PC_REQUIRES_PRIV "${PC_REQUIRES_PRIV}")
+list(REMOVE_DUPLICATES PC_LIBS_PRIV)
+string(REPLACE ";" " " PC_LIBS_PRIV "${PC_LIBS_PRIV}")
+
+# Macro to write pkg-config .pc configuration files
+macro ( make_pkgconfig_pc_file name )
+  file(READ "${PROJECT_SOURCE_DIR}/src/${name}.pc.in" FSTR)
+
+  string(REPLACE "%prefix%" "${CMAKE_INSTALL_PREFIX}" FSTR ${FSTR})
+  string(REPLACE "%exec_prefix%" "\${prefix}" FSTR ${FSTR})
+
+  if (IS_ABSOLUTE "${CMAKE_INSTALL_INCLUDEDIR}")
+    string(REPLACE "%includedir%" "${CMAKE_INSTALL_INCLUDEDIR}" FSTR ${FSTR})
+  else ()
+    string(REPLACE "%includedir%" "\${prefix}/${CMAKE_INSTALL_INCLUDEDIR}" FSTR ${FSTR})
+  endif ()
+
+  if (IS_ABSOLUTE "${CMAKE_INSTALL_LIBDIR}")
+    string(REPLACE "%libdir%" "${CMAKE_INSTALL_LIBDIR}" FSTR ${FSTR})
+  else ()
+    string(REPLACE "%libdir%" "\${prefix}/${CMAKE_INSTALL_LIBDIR}" FSTR ${FSTR})
+  endif ()  
+
+  string(REPLACE "%VERSION%" "${HB_VERSION}" FSTR ${FSTR})
+  string(REPLACE "%requires_private%" "${PC_REQUIRES_PRIV}" FSTR ${FSTR})
+  string(REPLACE "%libs_private%" "${PC_LIBS_PRIV}" FSTR ${FSTR})
+
+  file(WRITE "${PROJECT_BINARY_DIR}/${name}.pc" ${FSTR})
+
+  install(
+    FILES "${PROJECT_BINARY_DIR}/${name}.pc"
+    DESTINATION "${CMAKE_INSTALL_LIBDIR}/pkgconfig"
+    COMPONENT pkgconfig
+  )
+endmacro ( make_pkgconfig_pc_file )
+
 if (NOT SKIP_INSTALL_LIBRARIES AND NOT SKIP_INSTALL_ALL)
   install(TARGETS harfbuzz
     EXPORT harfbuzzConfig
@@ -709,6 +766,7 @@ if (NOT SKIP_INSTALL_LIBRARIES AND NOT SKIP_INSTALL_ALL)
     RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR}
     FRAMEWORK DESTINATION Library/Frameworks
   )
+  make_pkgconfig_pc_file("harfbuzz")
   install(EXPORT harfbuzzConfig
       NAMESPACE harfbuzz::
       DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake/harfbuzz
@@ -720,11 +778,13 @@ if (NOT SKIP_INSTALL_LIBRARIES AND NOT SKIP_INSTALL_ALL)
       RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR}
       FRAMEWORK DESTINATION Library/Frameworks
     )
+    make_pkgconfig_pc_file("harfbuzz-icu")
   endif ()
   if (HB_BUILD_SUBSET)
     install(TARGETS harfbuzz-subset
       ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR}
     )
+    make_pkgconfig_pc_file("harfbuzz-subset")
   endif ()
   if (HB_BUILD_UTILS)
     if (WIN32 AND BUILD_SHARED_LIBS)
@@ -753,6 +813,7 @@ if (NOT SKIP_INSTALL_LIBRARIES AND NOT SKIP_INSTALL_ALL)
       LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
       RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR}
     )
+    make_pkgconfig_pc_file("harfbuzz-gobject")
     if (HB_HAVE_INTROSPECTION)
       if ("${CMAKE_GENERATOR}" MATCHES "Visual Studio*")
         set (hb_libpath "${CMAKE_CURRENT_BINARY_DIR}/$<CONFIGURATION>")