simple_file: fix missing files problem

If the filter is NULL, simple file dereferences *NULL.  It just so happens on
a lot of systems this is zero and everything works, but on sime it isn't and
thus no files appear.  Fix this by explicitly checking for NULL and replacing
it with a pointer to the empty string.

Signed-off-by: James Bottomley <JBottomley@Parallels.com>

4 files changed, 5 insertions, 3 deletions

diff --git a/HashTool.c b/HashTool.c
index ebf028a..adb1749 100644
--- a/HashTool.c
+++ b/HashTool.c
@@ -70,7 +70,7 @@ enrol_hash(void)
 			L"This means it will Subsequently Boot with no prompting",
 			L"Remember to make sure it is a genuine binary before Enroling its hash",
 			NULL
-		}, L"\\", NULL, &file_name);
+		}, L"\\", L"", &file_name);
 
 	if (!file_name)
 		/* user pressed ESC */
diff --git a/KeyTool.c b/KeyTool.c
index 7e21559..6ad1e1e 100644
--- a/KeyTool.c
+++ b/KeyTool.c
@@ -78,7 +78,7 @@ select_and_apply(CHAR16 **title, CHAR16 *ext, int key, UINTN options)
 	EFI_HANDLE h = NULL;
 	int use_setsecurevariable = 0;
 
-	simple_file_selector(&h, title, NULL, ext, &file_name);
+	simple_file_selector(&h, title, L"\\", ext, &file_name);
 	if (file_name == NULL)
 		return;
 
diff --git a/Makefile b/Makefile
index 532465e..401509b 100644
--- a/Makefile
+++ b/Makefile
@@ -1,5 +1,5 @@
 EFIFILES = HelloWorld.efi LockDown.efi Loader.efi ReadVars.efi UpdateVars.efi \
-	KeyTool.efi HashTool.efi PreLoader.efi
+	KeyTool.efi HashTool.efi PreLoader.efi test.efi
 BINARIES = cert-to-efi-sig-list sig-list-to-certs sign-efi-sig-list \
 	hash-to-efi-sig-list
 
diff --git a/lib/simple_file.c b/lib/simple_file.c
index 53530e6..40ebf27 100644
--- a/lib/simple_file.c
+++ b/lib/simple_file.c
@@ -405,6 +405,8 @@ simple_file_selector(EFI_HANDLE *im, CHAR16 **title, CHAR16 *name,
 	*result = NULL;
 	if (!name)
 		name = L"\\";
+	if (!filter)
+		filter = L"";
 	if (!*im) {
 		EFI_HANDLE h;
 		CHAR16 *volname;