ignore nullptr warning in libstudxml, update to latest beta 9, and switch to submodule

.gitmodules

@@ -0,0 +1,3 @@
+[submodule "third-party/libstudxml"]
+	path = third-party/libstudxml
+	url = https://git.codesynthesis.com/libstudxml/libstudxml.git

source/CMakeLists.txt

@@ -18,7 +18,7 @@ set(XLNT_SOURCE_DIR ${XLNT_ROOT_DIR}/source)
 set(THIRD_PARTY_DIR ${XLNT_ROOT_DIR}/third-party)
 
 # Include libstudxml library
-add_subdirectory(${THIRD_PARTY_DIR}/libstudxml
+add_subdirectory(${THIRD_PARTY_DIR}/libstudxml.build
   ${CMAKE_CURRENT_BINARY_DIR}/third-party/libstudxml)
 
 if(COVERAGE)

source/detail/external/include_libstudxml.hpp

@@ -26,6 +26,7 @@
 #pragma clang diagnostic ignored "-Wweak-vtables"
 #pragma clang diagnostic ignored "-Wextra-semi"
 #pragma clang diagnostic ignored "-Wdeprecated"
+#pragma clang diagnostic ignored "-Wzero-as-null-pointer-constant"
 #include <libstudxml/content.hxx>
 #include <libstudxml/parser.hxx>
 #include <libstudxml/qname.hxx>

third-party/libstudxml

@@ -0,0 +1 @@
+Subproject commit e729667b0f34a39ce4a61339843af4154648667b

third-party/libstudxml.build/CMakeLists.txt

@@ -0,0 +1,79 @@
+cmake_minimum_required(VERSION 3.1)
+project(libstudxml)
+
+# Require C++11 compiler
+set(CMAKE_CXX_STANDARD 11)
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+
+set(LIBSTUDXML_ROOT_DIR ${CMAKE_CURRENT_SOURCE_DIR}/../libstudxml)
+set(LIBSTUDXML_INCLUDE_DIR ${LIBSTUDXML_ROOT_DIR}/../libstudxml)
+
+if(STATIC_CRT)
+  include(${CMAKE_CURRENT_SOURCE_DIR}/../../cmake/ucm.cmake)
+  ucm_set_runtime(STATIC)
+endif()
+
+set(LIBSTUDXML
+  ${LIBSTUDXML_ROOT_DIR}/libstudxml/parser.cxx
+  ${LIBSTUDXML_ROOT_DIR}/libstudxml/qname.cxx
+  ${LIBSTUDXML_ROOT_DIR}/libstudxml/serializer.cxx
+  ${LIBSTUDXML_ROOT_DIR}/libstudxml/value-traits.cxx
+  ${LIBSTUDXML_ROOT_DIR}/libstudxml/content
+  ${LIBSTUDXML_ROOT_DIR}/libstudxml/exception
+  ${LIBSTUDXML_ROOT_DIR}/libstudxml/forward
+  ${LIBSTUDXML_ROOT_DIR}/libstudxml/parser
+  ${LIBSTUDXML_ROOT_DIR}/libstudxml/qname
+  ${LIBSTUDXML_ROOT_DIR}/libstudxml/serializer
+  ${LIBSTUDXML_ROOT_DIR}/libstudxml/value-traits)
+
+set(GENX
+  ${LIBSTUDXML_ROOT_DIR}/libstudxml/details/genx/char-props.c
+  ${LIBSTUDXML_ROOT_DIR}/libstudxml/details/genx/genx.c
+  ${LIBSTUDXML_ROOT_DIR}/libstudxml/details/genx/genx.h)
+
+set(EXPAT
+  ${LIBSTUDXML_ROOT_DIR}/libstudxml/details/expat/xmlparse.c
+  ${LIBSTUDXML_ROOT_DIR}/libstudxml/details/expat/xmlrole.c
+  ${LIBSTUDXML_ROOT_DIR}/libstudxml/details/expat/xmltok.c
+  ${LIBSTUDXML_ROOT_DIR}/libstudxml/details/expat/ascii.h
+  ${LIBSTUDXML_ROOT_DIR}/libstudxml/details/expat/asciitab.h
+  ${LIBSTUDXML_ROOT_DIR}/libstudxml/details/expat/config.h
+  ${LIBSTUDXML_ROOT_DIR}/libstudxml/details/expat/expat_external.h
+  ${LIBSTUDXML_ROOT_DIR}/libstudxml/details/expat/expat.h
+  ${LIBSTUDXML_ROOT_DIR}/libstudxml/details/expat/iasciitab.h
+  ${LIBSTUDXML_ROOT_DIR}/libstudxml/details/expat/internal.h
+  ${LIBSTUDXML_ROOT_DIR}/libstudxml/details/expat/latin1tab.h
+  ${LIBSTUDXML_ROOT_DIR}/libstudxml/details/expat/nametab.h
+  ${LIBSTUDXML_ROOT_DIR}/libstudxml/details/expat/utf8tab.h
+  ${LIBSTUDXML_ROOT_DIR}/libstudxml/details/expat/xmlrole.h
+  ${LIBSTUDXML_ROOT_DIR}/libstudxml/details/expat/xmltok_impl.h
+  ${LIBSTUDXML_ROOT_DIR}/libstudxml/details/expat/xmltok.h)
+
+add_library(libstudxml OBJECT ${LIBSTUDXML} ${GENX} ${EXPAT})
+
+target_compile_definitions(libstudxml PUBLIC LIBSTUDXML_STATIC_LIB=1)
+target_include_directories(libstudxml
+  PUBLIC ${LIBSTUDXML_ROOT_DIR}
+  PUBLIC ${EXPAT_INCLUDE_DIRS})
+
+if(STATIC)
+  target_compile_definitions(libstudxml PUBLIC XML_STATIC=1)
+endif()
+
+# Prevent warning C4996 caused by strcpy, strncpy, sprintf in genx
+# TODO: would it be better to define this only in genx.c?
+if(MSVC)
+  target_compile_definitions(libstudxml PRIVATE _CRT_SECURE_NO_WARNINGS=1)
+endif()
+
+# Build with -fPIC when xlnt is a shared library
+# TODO: is this still necessary? try removing
+if(NOT STATIC)
+  set_target_properties(libstudxml PROPERTIES POSITION_INDEPENDENT_CODE 1)
+endif()
+
+# When xlnt is a static library, assume expat will be linked statically too
+# TODO: is this a valid assumption?
+if(STATIC)
+  target_compile_definitions(libstudxml PUBLIC XML_STATIC=1)
+endif()