diff --git a/src/resourcefiles/resourcefile.cpp b/src/resourcefiles/resourcefile.cpp
index b4280adf6..6b4c8c29b 100644
--- a/src/resourcefiles/resourcefile.cpp
+++ b/src/resourcefiles/resourcefile.cpp
@@ -90,11 +90,10 @@ FResourceLump::~FResourceLump()
 //
 //==========================================================================
 
-void FResourceLump::LumpNameSetup(const char *iname)
+void FResourceLump::LumpNameSetup(FString iname)
 {
-	const char *lname = strrchr(iname,'/');
-	lname = (lname == NULL) ? iname : lname + 1;
-	FString base = lname;
+	long slash = iname.LastIndexOf('/');
+	FString base = (slash >= 0) ? iname.Mid(slash + 1) : iname;
 	base = base.Left(base.LastIndexOf('.'));
 	uppercopy(Name, base);
 	Name[8] = 0;
diff --git a/src/resourcefiles/resourcefile.h b/src/resourcefiles/resourcefile.h
index 9927b1eae..c62981ca7 100644
--- a/src/resourcefiles/resourcefile.h
+++ b/src/resourcefiles/resourcefile.h
@@ -44,7 +44,7 @@ struct FResourceLump
 	virtual FileReader *NewReader();
 	virtual int GetFileOffset() { return -1; }
 	virtual int GetIndexNum() const { return 0; }
-	void LumpNameSetup(const char *iname);
+	void LumpNameSetup(FString iname);
 	void CheckEmbedded();
 
 	void *CacheLump();