Search for system libarchive before vendoring

Builds/CMake/deps/Findlibarchive.cmake

@@ -0,0 +1,23 @@
+find_package (PkgConfig REQUIRED)
+pkg_search_module (libarchive_PC QUIET libarchive>=3.3.3)
+
+if(static)
+  set(LIBARCHIVE_LIB libarchive.a)
+else()
+  set(LIBARCHIVE_LIB archive)
+endif()
+
+
+find_library (archive
+  NAMES ${LIBARCHIVE_LIB}
+  HINTS
+    ${libarchive_PC_LIBDIR}
+    ${libarchive_PC_LIBRARY_DIRS}
+  NO_DEFAULT_PATH)
+
+find_path (LIBARCHIVE_INCLUDE_DIR
+  NAMES archive.h
+  HINTS
+    ${libarchive_PC_INCLUDEDIR}
+    ${libarchive_PC_INCLUDEDIRS}
+  NO_DEFAULT_PATH)

Builds/CMake/deps/Findlz4.cmake

@@ -4,7 +4,7 @@ pkg_search_module (lz4_PC QUIET liblz4>=1.8)
 if(static)
   set(LZ4_LIB liblz4.a)
 else()
-  set(LZ4_LIB lz4)
+  set(LZ4_LIB lz4.so)
 endif()
 
 find_library (lz4

Builds/CMake/deps/Libarchive.cmake

@@ -2,6 +2,22 @@
    NIH dep: libarchive
 #]===================================================================]
 
+add_library (archive_lib STATIC IMPORTED GLOBAL)
+
+if (NOT WIN32)
+  find_package(libarchive REQUIRED)
+endif()
+
+if(libarchive)
+  set_target_properties (archive_lib PROPERTIES
+    IMPORTED_LOCATION_DEBUG
+      ${archive}
+    IMPORTED_LOCATION_RELEASE
+      ${archive}
+    INTERFACE_INCLUDE_DIRECTORIES
+      ${LIBARCHIVE_INCLUDE_DIR})
+
+else()
   set (lib_post "")
   if (MSVC)
     set (lib_post "_static")
@@ -83,7 +99,6 @@ ExternalProject_Get_Property (libarchive SOURCE_DIR)
   if (CMAKE_VERBOSE_MAKEFILE)
     print_ep_logs (libarchive)
   endif ()
-add_library (archive_lib STATIC IMPORTED GLOBAL)
   file (MAKE_DIRECTORY ${SOURCE_DIR}/libarchive)
   set_target_properties (archive_lib PROPERTIES
     IMPORTED_LOCATION_DEBUG
@@ -94,6 +109,8 @@ set_target_properties (archive_lib PROPERTIES
       ${SOURCE_DIR}/libarchive
     INTERFACE_COMPILE_DEFINITIONS
       LIBARCHIVE_STATIC)
+endif()
+
 add_dependencies (archive_lib libarchive)
 target_link_libraries (archive_lib INTERFACE lz4_lib)
 target_link_libraries (ripple_libs INTERFACE archive_lib)