xrCore: fix locating fs patches

Author: eagleivg

src/xrCore/FS.cpp

@@ -108,7 +108,13 @@ bool file_handle_internal(LPCSTR file_name, u32& size, int& hFile)
 #else // EDITOR
 static int open_internal(LPCSTR fn, int& handle)
 {
+#if defined(WINDOWS)
     return (_sopen_s(&handle, fn, _O_RDONLY | _O_BINARY, _SH_DENYNO, _S_IREAD));
+#elif defined(LINUX)
+    handle = open(fn, _O_RDONLY);
+
+    return (handle == -1);
+#endif
 }
 
 bool file_handle_internal(LPCSTR file_name, u32& size, int& file_handle)

src/xrCore/LocatorAPI.cpp

@@ -701,7 +701,14 @@ void CLocatorAPI::setup_fs_path(pcstr fs_name)
 #if defined(WINDOWS)
     _fullpath(full_current_directory, fs_path, sizeof full_current_directory);
 #elif defined(LINUX)
-    realpath(fs_path, full_current_directory);
+    if (SDL_strlen(fs_path) != 0)
+    {
+        char *tmp_path = realpath(fs_path, NULL);
+        SDL_strlcpy(full_current_directory, tmp_path, sizeof full_current_directory);
+        free(tmp_path);
+    }
+    else
+        SDL_strlcpy(full_current_directory, SDL_GetBasePath(), sizeof full_current_directory);
 #endif
 
     FS_Path* path = new FS_Path(full_current_directory, "", "", "", 0);

src/xrCore/xrCore.cpp

@@ -57,9 +57,7 @@ void xrCore::Initialize(pcstr _ApplicationName, LogCallback cb, bool init_fs, pc
         }
 #endif
 
-#if defined(WINDOWS)
-        GetCurrentDirectory(sizeof(WorkingPath), WorkingPath);
-#endif
+        SDL_strlcpy(WorkingPath, SDL_GetBasePath(), sizeof(WorkingPath));
 
 #if defined(WINDOWS)
         // User/Comp Name