0025367: IGES and BRep persistence - support unicode file names on Windows

OSD_OpenFile.hxx header is created for using in file open operations with Unicode names.

Fix for STEP files reading.

Adding test cases for issue 25367
Update test case for issue 25364
Update test cases due to improvements

src/StepFile/StepFile_Read.cxx

@@ -122,12 +122,7 @@ Standard_Integer StepFile_Read
 
   checkread->Clear();
   recfile_modeprint ( (modepr > 0 ? modepr-1 : 0) );
-#ifdef _WIN32
-  TCollection_ExtendedString aFileNameW(ficnom, Standard_True);
-  FILE* newin = stepread_setinput((char*)aFileNameW.ToExtString());
-#else
   FILE* newin = stepread_setinput(ficnom);
-#endif
   if (!newin) return -1;
 #ifdef CHRONOMESURE
   Standard_Integer n ; 

src/StepFile/stepread.c

@@ -24,6 +24,7 @@
 #include <stdio.h>
 #include <string.h>
 #include "recfile.ph"
+#include <OSD_OpenFile.hxx>
 
 /*    StepFile_Error.c
 
@@ -84,13 +85,8 @@ FILE* stepread_setinput (char* nomfic)
 {
   FILE* newin ;
   if (strlen(nomfic) == 0) return stepin ;
-#ifdef _WIN32
-  // file name is treated as UTF-8 string
-  // nomfic is prepared UTF-8 string
-  newin = _wfopen((const wchar_t*)nomfic, L"r") ;
-#else
-  newin = fopen(nomfic,"r") ;
-#endif
+  newin = OSD_OpenFile(nomfic,"r");
+
   if (newin == NULL) {
     return NULL ;
   } else {