Support FindBotan with version

Author: hks2002

cmake_modules/FindBotan.cmake

@@ -1,30 +1,40 @@
-function(find_botan_pkgconfig package_name botan_ver)
-  if (TARGET Botan::Botan)
+function(find_botan_pkgconfig package_name)
+  if(TARGET Botan::Botan)
     return()
-  endif ()
+  endif()
 
-  pkg_check_modules(Botan QUIET IMPORTED_TARGET ${package_name})
-  if (TARGET PkgConfig::Botan)
+  pkg_check_modules(
+    Botan
+    QUIET
+    IMPORTED_TARGET
+    GLOBAL
+    ${package_name}
+  )
+  if(TARGET PkgConfig::Botan)
     add_library(Botan::Botan ALIAS PkgConfig::Botan)
 
-    if(botan_ver EQUAL 3)
+    if(${Botan_FIND_VERSION} EQUAL 3)
       target_compile_features(PkgConfig::Botan INTERFACE cxx_std_20)
     endif()
-  endif ()
+  endif()
 endfunction()
 
-function(find_botan_search package_name botan_ver)
-  if (TARGET Botan::Botan)
-    return()
-  endif ()
-  find_path(Botan_INCLUDE_DIRS NAMES botan/botan.h
-            PATH_SUFFIXES ${package_name}
-            DOC "The Botan include directory")
-
-  find_library(Botan_LIBRARIES NAMES botan ${package_name}
-              DOC "The Botan library")
+function(find_botan_search package_name)
+  # botan2 have botan.h, but botan3 does not, botan3 using auto_rng.h instead
+  find_path(
+    Botan_INCLUDE_DIRS
+    NAMES botan/botan.h botan/auto_rng.h
+    HINTS ${BOTAN_ROOT_DIR}/include
+    PATH_SUFFIXES ${package_name}
+    DOC "The Botan include directory"
+  )
 
-  mark_as_advanced(Botan_INCLUDE_DIRS Botan_LIBRARIES)
+  find_library(
+    Botan_LIBRARIES
+    NAMES botan ${package_name}
+    HINTS ${BOTAN_ROOT_DIR}/lib
+    DOC "The Botan library"
+  )
 
   add_library(Botan::Botan IMPORTED UNKNOWN)
   set_target_properties(
@@ -33,29 +43,32 @@ function(find_botan_search package_name botan_ver)
     IMPORTED_LOCATION "${Botan_LIBRARIES}"
     INTERFACE_INCLUDE_DIRECTORIES "${Botan_INCLUDE_DIRS}"
   )
-  if(botan_ver EQUAL 3)
+  if(${Botan_FIND_VERSION} EQUAL 3)
     target_compile_features(Botan::Botan INTERFACE cxx_std_20)
   endif()
 
-  if (WIN32)
+  if(WIN32)
     target_compile_definitions(Botan::Botan INTERFACE -DNOMINMAX=1)
-  endif ()
+  endif()
 endfunction()
 
+# ######################################################################################################################
+# Using find_package with verion: find_package(Botan 3) or find_package(Botan 2)
+if(NOT DEFINED Botan_FIND_VERSION)
+  message(FATAL_ERROR "Must specify Botan version: find_package(Botan 3) or find_package(Botan 2)")
+endif()
 
-find_package(PkgConfig)
-if(NOT WIN32 AND PKG_CONFIG_FOUND)
-  # find_botan_pkgconfig(botan-2 2)
-  find_botan_pkgconfig(botan-3 3)
+if(NOT WIN32)
+  find_package(PkgConfig)
+  if(PKG_CONFIG_FOUND)
+    find_botan_pkgconfig(botan-${Botan_FIND_VERSION})
+  endif()
 endif()
 
 if(NOT TARGET Botan::Botan)
-  # find_botan_search(botan-2 2)
-  find_botan_search(botan-3 3)
+  find_botan_search(botan-${Botan_FIND_VERSION})
 endif()
 
 include(FindPackageHandleStandardArgs)
-find_package_handle_standard_args(
-  Botan
-  REQUIRED_VARS Botan_LIBRARIES Botan_INCLUDE_DIRS
-)
+find_package_handle_standard_args(Botan REQUIRED_VARS Botan_LIBRARIES Botan_INCLUDE_DIRS)
+mark_as_advanced(Botan_INCLUDE_DIRS Botan_LIBRARIES)