Fix discovery of `libsodium`

Summary:
By putting this in `fizz-config.cmake`, we can use depend on the `sodium` target without compromising our dependents ability to find the library.

Put the search module in the common location under `fbcode_builder/CMake` to let dependents use it.

Reviewed By: yfeldblum

Differential Revision: D24686041

fbshipit-source-id: 942d1ab34feef6cadac2b584eb8cb2d999bae0ca

build/fbcode_builder/CMake/FindSodium.cmake

+# Written in 2016 by Henrik Steffen Gaßmann <henrik@gassmann.onl>
+#
+# To the extent possible under law, the author(s) have dedicated all
+# copyright and related and neighboring rights to this software to the
+# public domain worldwide. This software is distributed without any warranty.
+#
+# You should have received a copy of the CC0 Public Domain Dedication
+# along with this software. If not, see
+#
+#     http://creativecommons.org/publicdomain/zero/1.0/
+#
+########################################################################
+# Tries to find the local libsodium installation.
+#
+# On Windows the sodium_DIR environment variable is used as a default
+# hint which can be overridden by setting the corresponding cmake variable.
+#
+# Once done the following variables will be defined:
+#
+#   sodium_FOUND
+#   sodium_INCLUDE_DIR
+#   sodium_LIBRARY_DEBUG
+#   sodium_LIBRARY_RELEASE
+#
+#
+# Furthermore an imported "sodium" target is created.
+#
+
+if (CMAKE_C_COMPILER_ID STREQUAL "GNU"
+    OR CMAKE_C_COMPILER_ID STREQUAL "Clang")
+    set(_GCC_COMPATIBLE 1)
+endif()
+
+# static library option
+if (NOT DEFINED sodium_USE_STATIC_LIBS)
+    option(sodium_USE_STATIC_LIBS "enable to statically link against sodium" OFF)
+endif()
+if(NOT (sodium_USE_STATIC_LIBS EQUAL sodium_USE_STATIC_LIBS_LAST))
+    unset(sodium_LIBRARY CACHE)
+    unset(sodium_LIBRARY_DEBUG CACHE)
+    unset(sodium_LIBRARY_RELEASE CACHE)
+    unset(sodium_DLL_DEBUG CACHE)
+    unset(sodium_DLL_RELEASE CACHE)
+    set(sodium_USE_STATIC_LIBS_LAST ${sodium_USE_STATIC_LIBS} CACHE INTERNAL "internal change tracking variable")
+endif()
+
+
+########################################################################
+# UNIX
+if (UNIX)
+    # import pkg-config
+    find_package(PkgConfig QUIET)
+    if (PKG_CONFIG_FOUND)
+        pkg_check_modules(sodium_PKG QUIET libsodium)
+    endif()
+
+    if(sodium_USE_STATIC_LIBS)
+        foreach(_libname ${sodium_PKG_STATIC_LIBRARIES})
+            if (NOT _libname MATCHES "^lib.*\\.a$") # ignore strings already ending with .a
+                list(INSERT sodium_PKG_STATIC_LIBRARIES 0 "lib${_libname}.a")
+            endif()
+        endforeach()
+        list(REMOVE_DUPLICATES sodium_PKG_STATIC_LIBRARIES)
+
+        # if pkgconfig for libsodium doesn't provide
+        # static lib info, then override PKG_STATIC here..
+        if (NOT sodium_PKG_STATIC_FOUND)
+            set(sodium_PKG_STATIC_LIBRARIES libsodium.a)
+        endif()
+
+        set(XPREFIX sodium_PKG_STATIC)
+    else()
+        if (NOT sodium_PKG_FOUND)
+            set(sodium_PKG_LIBRARIES sodium)
+        endif()
+
+        set(XPREFIX sodium_PKG)
+    endif()
+
+    find_path(sodium_INCLUDE_DIR sodium.h
+        HINTS ${${XPREFIX}_INCLUDE_DIRS}
+    )
+    find_library(sodium_LIBRARY_DEBUG NAMES ${${XPREFIX}_LIBRARIES}
+        HINTS ${${XPREFIX}_LIBRARY_DIRS}
+    )
+    find_library(sodium_LIBRARY_RELEASE NAMES ${${XPREFIX}_LIBRARIES}
+        HINTS ${${XPREFIX}_LIBRARY_DIRS}
+    )
+
+
+########################################################################
+# Windows
+elseif (WIN32)
+    set(sodium_DIR "$ENV{sodium_DIR}" CACHE FILEPATH "sodium install directory")
+    mark_as_advanced(sodium_DIR)
+
+    find_path(sodium_INCLUDE_DIR sodium.h
+        HINTS ${sodium_DIR}
+        PATH_SUFFIXES include
+    )
+
+    if (MSVC)
+        # detect target architecture
+        file(WRITE "${CMAKE_CURRENT_BINARY_DIR}/arch.cpp" [=[
+            #if defined _M_IX86
+            #error ARCH_VALUE x86_32
+            #elif defined _M_X64
+            #error ARCH_VALUE x86_64
+            #endif
+            #error ARCH_VALUE unknown
+        ]=])
+        try_compile(_UNUSED_VAR "${CMAKE_CURRENT_BINARY_DIR}" "${CMAKE_CURRENT_BINARY_DIR}/arch.cpp"
+            OUTPUT_VARIABLE _COMPILATION_LOG
+        )
+        string(REGEX REPLACE ".*ARCH_VALUE ([a-zA-Z0-9_]+).*" "\\1" _TARGET_ARCH "${_COMPILATION_LOG}")
+
+        # construct library path
+        if (_TARGET_ARCH STREQUAL "x86_32")
+            string(APPEND _PLATFORM_PATH "Win32")
+        elseif(_TARGET_ARCH STREQUAL "x86_64")
+            string(APPEND _PLATFORM_PATH "x64")
+        else()
+            message(FATAL_ERROR "the ${_TARGET_ARCH} architecture is not supported by Findsodium.cmake.")
+        endif()
+        string(APPEND _PLATFORM_PATH "/$$CONFIG$$")
+
+        if (MSVC_VERSION LESS 1900)
+            math(EXPR _VS_VERSION "${MSVC_VERSION} / 10 - 60")
+        else()
+            math(EXPR _VS_VERSION "${MSVC_VERSION} / 10 - 50")
+        endif()
+        string(APPEND _PLATFORM_PATH "/v${_VS_VERSION}")
+
+        if (sodium_USE_STATIC_LIBS)
+            string(APPEND _PLATFORM_PATH "/static")
+        else()
+            string(APPEND _PLATFORM_PATH "/dynamic")
+        endif()
+
+        string(REPLACE "$$CONFIG$$" "Debug" _DEBUG_PATH_SUFFIX "${_PLATFORM_PATH}")
+        string(REPLACE "$$CONFIG$$" "Release" _RELEASE_PATH_SUFFIX "${_PLATFORM_PATH}")
+
+        find_library(sodium_LIBRARY_DEBUG libsodium.lib
+            HINTS ${sodium_DIR}
+            PATH_SUFFIXES ${_DEBUG_PATH_SUFFIX}
+        )
+        find_library(sodium_LIBRARY_RELEASE libsodium.lib
+            HINTS ${sodium_DIR}
+            PATH_SUFFIXES ${_RELEASE_PATH_SUFFIX}
+        )
+        if (NOT sodium_USE_STATIC_LIBS)
+            set(CMAKE_FIND_LIBRARY_SUFFIXES_BCK ${CMAKE_FIND_LIBRARY_SUFFIXES})
+            set(CMAKE_FIND_LIBRARY_SUFFIXES ".dll")
+            find_library(sodium_DLL_DEBUG libsodium
+                HINTS ${sodium_DIR}
+                PATH_SUFFIXES ${_DEBUG_PATH_SUFFIX}
+            )
+            find_library(sodium_DLL_RELEASE libsodium
+                HINTS ${sodium_DIR}
+                PATH_SUFFIXES ${_RELEASE_PATH_SUFFIX}
+            )
+            set(CMAKE_FIND_LIBRARY_SUFFIXES ${CMAKE_FIND_LIBRARY_SUFFIXES_BCK})
+        endif()
+
+    elseif(_GCC_COMPATIBLE)
+        if (sodium_USE_STATIC_LIBS)
+            find_library(sodium_LIBRARY_DEBUG libsodium.a
+                HINTS ${sodium_DIR}
+                PATH_SUFFIXES lib
+            )
+            find_library(sodium_LIBRARY_RELEASE libsodium.a
+                HINTS ${sodium_DIR}
+                PATH_SUFFIXES lib
+            )
+        else()
+            find_library(sodium_LIBRARY_DEBUG libsodium.dll.a
+                HINTS ${sodium_DIR}
+                PATH_SUFFIXES lib
+            )
+            find_library(sodium_LIBRARY_RELEASE libsodium.dll.a
+                HINTS ${sodium_DIR}
+                PATH_SUFFIXES lib
+            )
+
+            file(GLOB _DLL
+                LIST_DIRECTORIES false
+                RELATIVE "${sodium_DIR}/bin"
+                "${sodium_DIR}/bin/libsodium*.dll"
+            )
+            find_library(sodium_DLL_DEBUG ${_DLL} libsodium
+                HINTS ${sodium_DIR}
+                PATH_SUFFIXES bin
+            )
+            find_library(sodium_DLL_RELEASE ${_DLL} libsodium
+                HINTS ${sodium_DIR}
+                PATH_SUFFIXES bin
+            )
+        endif()
+    else()
+        message(FATAL_ERROR "this platform is not supported by FindSodium.cmake")
+    endif()
+
+
+########################################################################
+# unsupported
+else()
+    message(FATAL_ERROR "this platform is not supported by FindSodium.cmake")
+endif()
+
+
+########################################################################
+# common stuff
+
+# extract sodium version
+if (sodium_INCLUDE_DIR)
+    set(_VERSION_HEADER "${_INCLUDE_DIR}/sodium/version.h")
+    if (EXISTS _VERSION_HEADER)
+        file(READ "${_VERSION_HEADER}" _VERSION_HEADER_CONTENT)
+        string(REGEX REPLACE ".*#[ \t]*define[ \t]*SODIUM_VERSION_STRING[ \t]*\"([^\n]*)\".*" "\\1"
+            sodium_VERSION "${_VERSION_HEADER_CONTENT}")
+        set(sodium_VERSION "${sodium_VERSION}" PARENT_SCOPE)
+    endif()
+endif()
+
+# communicate results
+include(FindPackageHandleStandardArgs)
+find_package_handle_standard_args(
+    Sodium # The name must be either uppercase or match the filename case.
+    REQUIRED_VARS
+        sodium_LIBRARY_RELEASE
+        sodium_LIBRARY_DEBUG
+        sodium_INCLUDE_DIR
+    VERSION_VAR
+        sodium_VERSION
+)
+
+if(Sodium_FOUND)
+    set(sodium_LIBRARIES
+        optimized ${sodium_LIBRARY_RELEASE} debug ${sodium_LIBRARY_DEBUG})
+endif()
+
+# mark file paths as advanced
+mark_as_advanced(sodium_INCLUDE_DIR)
+mark_as_advanced(sodium_LIBRARY_DEBUG)
+mark_as_advanced(sodium_LIBRARY_RELEASE)
+if (WIN32)
+    mark_as_advanced(sodium_DLL_DEBUG)
+    mark_as_advanced(sodium_DLL_RELEASE)
+endif()
+
+# create imported target
+if(sodium_USE_STATIC_LIBS)
+    set(_LIB_TYPE STATIC)
+else()
+    set(_LIB_TYPE SHARED)
+endif()
+add_library(sodium ${_LIB_TYPE} IMPORTED)
+
+set_target_properties(sodium PROPERTIES
+    INTERFACE_INCLUDE_DIRECTORIES "${sodium_INCLUDE_DIR}"
+    IMPORTED_LINK_INTERFACE_LANGUAGES "C"
+)
+
+if (sodium_USE_STATIC_LIBS)
+    set_target_properties(sodium PROPERTIES
+        INTERFACE_COMPILE_DEFINITIONS "SODIUM_STATIC"
+        IMPORTED_LOCATION "${sodium_LIBRARY_RELEASE}"
+        IMPORTED_LOCATION_DEBUG "${sodium_LIBRARY_DEBUG}"
+    )
+else()
+    if (UNIX)
+        set_target_properties(sodium PROPERTIES
+            IMPORTED_LOCATION "${sodium_LIBRARY_RELEASE}"
+            IMPORTED_LOCATION_DEBUG "${sodium_LIBRARY_DEBUG}"
+        )
+    elseif (WIN32)
+        set_target_properties(sodium PROPERTIES
+            IMPORTED_IMPLIB "${sodium_LIBRARY_RELEASE}"
+            IMPORTED_IMPLIB_DEBUG "${sodium_LIBRARY_DEBUG}"
+        )
+        if (NOT (sodium_DLL_DEBUG MATCHES ".*-NOTFOUND"))
+            set_target_properties(sodium PROPERTIES
+                IMPORTED_LOCATION_DEBUG "${sodium_DLL_DEBUG}"
+            )
+        endif()
+        if (NOT (sodium_DLL_RELEASE MATCHES ".*-NOTFOUND"))
+            set_target_properties(sodium PROPERTIES
+                IMPORTED_LOCATION_RELWITHDEBINFO "${sodium_DLL_RELEASE}"
+                IMPORTED_LOCATION_MINSIZEREL "${sodium_DLL_RELEASE}"
+                IMPORTED_LOCATION_RELEASE "${sodium_DLL_RELEASE}"
+            )
+        endif()
+    endif()
+endif()