revert xnnpack cmakelist and fix file_data_loader

Author: chinazhangchao

backends/xnnpack/CMakeLists.txt

@@ -73,33 +73,17 @@ foreach(fbs_file ${_xnnpack_schema__srcs})
 endforeach()
 
 # Generate the headers from the .fbs files.
-if(WIN32)
-  add_custom_command(
-    OUTPUT ${_xnnpack_schema__outputs}
-    COMMAND
-      ${FLATC_EXECUTABLE} --cpp --cpp-std c++11 --scoped-enums -o
-      "${_xnnpack_schema__include_dir}/executorch/backends/xnnpack/serialization"
-      ${_xnnpack_schema__srcs}
-    COMMAND
-      powershell -Command
-      "Move-Item -Path ${_xnnpack_flatbuffer__outputs} -Destination ${_xnnpack_schema__outputs}"
-    WORKING_DIRECTORY ${EXECUTORCH_ROOT}
-    COMMENT "Generating xnnpack_schema headers"
-    VERBATIM
-  )
-else()
-  add_custom_command(
-    OUTPUT ${_xnnpack_schema__outputs}
-    COMMAND
-      ${FLATC_EXECUTABLE} --cpp --cpp-std c++11 --scoped-enums -o
-      "${_xnnpack_schema__include_dir}/executorch/backends/xnnpack/serialization"
-      ${_xnnpack_schema__srcs}
-    COMMAND mv ${_xnnpack_flatbuffer__outputs} ${_xnnpack_schema__outputs}
-    WORKING_DIRECTORY ${EXECUTORCH_ROOT}
-    COMMENT "Generating xnnpack_schema headers"
-    VERBATIM
-  )
-endif()
+add_custom_command(
+  OUTPUT ${_xnnpack_schema__outputs}
+  COMMAND
+    ${FLATC_EXECUTABLE} --cpp --cpp-std c++11 --scoped-enums -o
+    "${_xnnpack_schema__include_dir}/executorch/backends/xnnpack/serialization"
+    ${_xnnpack_schema__srcs}
+  COMMAND mv ${_xnnpack_flatbuffer__outputs} ${_xnnpack_schema__outputs}
+  WORKING_DIRECTORY ${EXECUTORCH_ROOT}
+  COMMENT "Generating xnnpack_schema headers"
+  VERBATIM
+)
 
 add_library(xnnpack_schema INTERFACE ${_xnnpack_schema__outputs})
 set_target_properties(xnnpack_schema PROPERTIES LINKER_LANGUAGE CXX)

extension/data_loader/file_data_loader.cpp

@@ -17,7 +17,7 @@
 #include <fcntl.h>
 #include <sys/stat.h>
 #include <sys/types.h>
-#include <unistd.h>
+#include <executorch/runtime/platform/compat_unistd.h>
 
 #include <executorch/runtime/core/error.h>
 #include <executorch/runtime/core/result.h>
@@ -71,6 +71,9 @@ FileDataLoader::~FileDataLoader() {
   std::free(const_cast<char*>(file_name_));
   // fd_ can be -1 if this instance was moved from, but closing a negative fd is
   // safe (though it will return an error).
+  if (fd_ == -1) {
+    return;
+  }
   ::close(fd_);
 }