From 6bb404315405ba6f5217c061c0e3fb2a0d19099b Mon Sep 17 00:00:00 2001
From: Themba Dube <embeddedthemba@gmail.com>
Date: Thu, 24 Dec 2020 14:05:46 -0500
Subject: [PATCH] Skip flushing file if lfs_file_rawseek() doesn't change
 position

---
 lfs.c | 21 +++++++++++++--------
 1 file changed, 13 insertions(+), 8 deletions(-)

diff --git a/lfs.c b/lfs.c
index d7439fe..c59d3d2 100644
--- a/lfs.c
+++ b/lfs.c
@@ -3048,14 +3048,6 @@ relocate:
 
 static lfs_soff_t lfs_file_rawseek(lfs_t *lfs, lfs_file_t *file,
         lfs_soff_t off, int whence) {
-#ifndef LFS_READONLY
-    // write out everything beforehand, may be noop if rdonly
-    int err = lfs_file_flush(lfs, file);
-    if (err) {
-        return err;
-    }
-#endif
-
     // find new pos
     lfs_off_t npos = file->pos;
     if (whence == LFS_SEEK_SET) {
@@ -3071,6 +3063,19 @@ static lfs_soff_t lfs_file_rawseek(lfs_t *lfs, lfs_file_t *file,
         return LFS_ERR_INVAL;
     }
 
+    if (file->pos == npos) {
+        // noop - position has not changed
+        return npos;
+    }
+
+#ifndef LFS_READONLY
+    // write out everything beforehand, may be noop if rdonly
+    int err = lfs_file_flush(lfs, file);
+    if (err) {
+        return err;
+    }
+#endif
+
     // update pos
     file->pos = npos;
     return npos;