CMake: Use Hunter to manage dependencies

Author: ruslo

cmake/WebPConfig.cmake.in

@@ -3,9 +3,26 @@ set(WEBP_VERSION ${WebP_VERSION})
 
 @PACKAGE_INIT@
 
+find_package(PNG CONFIG REQUIRED)
+find_package(JPEG CONFIG REQUIRED)
+if(NOT MSYS)
+  # See 'cmake/deps.cmake'
+  find_package(TIFF CONFIG REQUIRED)
+endif()
+if(NOT MINGW AND NOT MSYS)
+  # See 'cmake/deps.cmake'
+  find_package(giflib CONFIG REQUIRED)
+endif()
+
+check_required_components("@PROJECT_NAME@")
+
 include ("${CMAKE_CURRENT_LIST_DIR}/@PROJECT_NAME@Targets.cmake")
 
+if(0)
+
 set(WebP_INCLUDE_DIRS "@CMAKE_INSTALL_FULL_INCLUDEDIR@")
 set(WEBP_INCLUDE_DIRS ${WebP_INCLUDE_DIRS})
 set(WebP_LIBRARIES "@INSTALLED_LIBRARIES@")
 set(WEBP_LIBRARIES "${WebP_LIBRARIES}")
+
+endif()

cmake/deps.cmake

@@ -70,6 +70,46 @@ if(NOT HAVE_MATH_LIBRARY)
   list(APPEND WEBP_DEP_LIBRARIES m)
 endif()
 
+if(HUNTER_ENABLED)
+  hunter_add_package(PNG)
+  find_package(PNG CONFIG REQUIRED)
+  list(APPEND WEBP_DEP_IMG_LIBRARIES PNG::png)
+  set(WEBP_HAVE_PNG 1)
+  set(PNG_FOUND 1)
+
+  hunter_add_package(Jpeg)
+  find_package(JPEG CONFIG REQUIRED)
+  list(APPEND WEBP_DEP_IMG_LIBRARIES JPEG::jpeg)
+  set(WEBP_HAVE_JPEG 1)
+  set(JPEG_FOUND 1)
+
+  if(MSYS)
+    # TIFF is currently not supported by Hunter on MSYS:
+    # - https://github.com/ingenue/hunter/blob/8e37b969b18ff75857d2b75c8acdf1e9caca2549/appveyor.yml#L31-L34
+    set(WEBP_HAVE_TIFF 0)
+    set(TIFF_FOUND 0)
+  else()
+    hunter_add_package(TIFF)
+    find_package(TIFF CONFIG REQUIRED)
+    list(APPEND WEBP_DEP_IMG_LIBRARIES TIFF::libtiff)
+    set(WEBP_HAVE_TIFF 1)
+    set(TIFF_FOUND 1)
+  endif()
+
+  if(MINGW OR MSYS)
+    # giflib is currently not supported by Hunter on MinGW and MSYS:
+    # - https://github.com/ingenue/hunter/blob/ab5a2b7507427b2e1110717c35c29a78815394c6/appveyor.yml#L27-L37
+    set(WEBP_HAVE_GIF 0)
+    set(GIF_FOUND 0)
+  else()
+    hunter_add_package(giflib)
+    find_package(giflib CONFIG REQUIRED)
+    list(APPEND WEBP_DEP_GIF_LIBRARIES giflib::giflib)
+    set(WEBP_HAVE_GIF 1)
+    set(GIF_FOUND 1)
+  endif()
+else()
+
 # Find the standard image libraries.
 set(WEBP_DEP_IMG_LIBRARIES)
 set(WEBP_DEP_IMG_INCLUDE_DIRS)
@@ -116,6 +156,8 @@ if(GIF_FOUND)
   endif()
 endif()
 
+endif()
+
 # Check for specific headers.
 include(CheckIncludeFiles)
 check_include_files("stdlib.h;stdarg.h;string.h;float.h" STDC_HEADERS)