SDL: filesystem: Turn off case-insensitivity if glob pattern is NULL.

From ff651a7941752c275c1940f3e729f8183a46fe18 Mon Sep 17 00:00:00 2001
From: "Ryan C. Gordon" <[EMAIL REDACTED]>
Date: Thu, 4 Apr 2024 10:40:36 -0400
Subject: [PATCH] filesystem: Turn off case-insensitivity if glob pattern is
 NULL.

Just a small optimization; it'll avoid some allocations and case-folding we
don't actually need the results of later.
---
 src/filesystem/SDL_filesystem.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/filesystem/SDL_filesystem.c b/src/filesystem/SDL_filesystem.c
index 2c67999c65aec..65be3e0f4e32a 100644
--- a/src/filesystem/SDL_filesystem.c
+++ b/src/filesystem/SDL_filesystem.c
@@ -270,8 +270,13 @@ char **SDL_InternalGlobDirectory(const char *path, const char *pattern, Uint32 f
         path = pathcpy;
     }
 
+    if (!pattern) {
+        flags &= ~SDL_GLOB_CASEINSENSITIVE;  // avoid some unnecessary allocations and work later.
+    }
+
     char *folded = NULL;
-    if (pattern && (flags & SDL_GLOB_CASEINSENSITIVE)) {
+    if (flags & SDL_GLOB_CASEINSENSITIVE) {
+        SDL_assert(pattern != NULL);
         folded = CaseFoldUtf8String(pattern);
         if (!folded) {
             SDL_free(pathcpy);