Add optional support for Botan3 (#8994)

cmake/FindBotan3.cmake

@@ -0,0 +1,106 @@
+# Copyright (c) 2018 Ribose Inc.
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+# 1. Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in the
+#    documentation and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+# TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+# PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS
+# BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+# POSSIBILITY OF SUCH DAMAGE.
+
+#.rst:
+# FindBotan3
+# -----------
+#
+# Find the botan-3 library.
+#
+# IMPORTED Targets
+# ^^^^^^^^^^^^^^^^
+#
+# This module defines :prop_tgt:`IMPORTED` targets:
+#
+# ``Botan3::Botan3``
+#   The botan-3 library, if found.
+#
+# Result variables
+# ^^^^^^^^^^^^^^^^
+#
+# This module defines the following variables:
+#
+# ::
+#
+#   BOTAN3_FOUND          - true if the headers and library were found
+#   BOTAN3_INCLUDE_DIRS   - where to find headers
+#   BOTAN3_LIBRARIES      - list of libraries to link
+#   BOTAN3_VERSION        - library version that was found, if any
+
+# find the headers
+find_path(BOTAN3_INCLUDE_DIR
+  NAMES botan/version.h
+  PATH_SUFFIXES botan-3
+)
+
+# find the library
+find_library(BOTAN3_LIBRARY NAMES botan-3 libbotan-3 botan)
+
+# determine the version
+if(BOTAN3_INCLUDE_DIR AND EXISTS "${BOTAN3_INCLUDE_DIR}/botan/build.h")
+    file(STRINGS "${BOTAN3_INCLUDE_DIR}/botan/build.h" botan3_version_str
+      REGEX "^#define[\t ]+(BOTAN_VERSION_[A-Z]+)[\t ]+[0-9]+")
+
+    string(REGEX REPLACE ".*#define[\t ]+BOTAN_VERSION_MAJOR[\t ]+([0-9]+).*"
+           "\\1" _botan3_version_major "${botan3_version_str}")
+    string(REGEX REPLACE ".*#define[\t ]+BOTAN_VERSION_MINOR[\t ]+([0-9]+).*"
+           "\\1" _botan3_version_minor "${botan3_version_str}")
+    string(REGEX REPLACE ".*#define[\t ]+BOTAN_VERSION_PATCH[\t ]+([0-9]+).*"
+           "\\1" _botan3_version_patch "${botan3_version_str}")
+    set(BOTAN3_VERSION "${_botan3_version_major}.${_botan3_version_minor}.${_botan3_version_patch}"
+                       CACHE INTERNAL "The version of Botan which was detected")
+endif()
+
+include(FindPackageHandleStandardArgs)
+find_package_handle_standard_args(Botan3
+  REQUIRED_VARS BOTAN3_LIBRARY BOTAN3_INCLUDE_DIR
+  VERSION_VAR BOTAN3_VERSION
+)
+
+if(BOTAN3_FOUND)
+  set(BOTAN3_INCLUDE_DIRS ${BOTAN3_INCLUDE_DIR} ${PC_BOTAN3_INCLUDE_DIRS})
+  set(BOTAN3_LIBRARIES ${BOTAN3_LIBRARY})
+endif()
+
+if(BOTAN3_FOUND AND NOT TARGET Botan3::Botan3)
+  # create the new library target
+  add_library(Botan3::Botan3 UNKNOWN IMPORTED)
+  # set the required include dirs for the target
+  if(BOTAN3_INCLUDE_DIRS)
+    set_target_properties(Botan3::Botan3
+      PROPERTIES
+        INTERFACE_INCLUDE_DIRECTORIES "${BOTAN3_INCLUDE_DIRS}"
+    )
+  endif()
+  # set the required libraries for the target
+  if(EXISTS "${BOTAN3_LIBRARY}")
+    set_target_properties(Botan3::Botan3
+      PROPERTIES
+        IMPORTED_LINK_INTERFACE_LANGUAGES "C"
+        IMPORTED_LOCATION "${BOTAN3_LIBRARY}"
+    )
+  endif()
+endif()
+
+mark_as_advanced(BOTAN3_INCLUDE_DIR BOTAN3_LIBRARY)