[PATCH 1/4] erofs-utils: fsck: fix hole handling during extraction

[Yifan Zhao <stopire@gmail.com>]

Fix the following two issues in fsck.erofs --extract:

- Trailing holes leave extracted files too short.
- With --xattr-inode-digest, holes are hashed without advancing the
  output offset, so subsequent data is written at an earlier offset.

Assisted-by: Codex:gpt-6-astra
Signed-off-by: Yifan Zhao <stopire@gmail.com>
---
 fsck/main.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/fsck/main.c b/fsck/main.c
index b2d8f1a..55da9ea 100644
--- a/fsck/main.c
+++ b/fsck/main.c
@@ -569,7 +569,8 @@ static int erofs_verify_inode_data(struct erofs_inode *inode, int outfd,
 						(const u8 *)zeros, chunk);
 					remain -= chunk;
 				}
-			} else if (outfd >= 0) {
+			}
+			if (outfd >= 0) {
 				ret = lseek(outfd, map.m_llen, SEEK_CUR);
 				if (ret < 0) {
 					ret = -errno;
@@ -855,6 +856,11 @@ again:
 	}
 
 	ret = erofsfsck_calc_inode_data(inode, fd);
+	if (!ret && ftruncate(fd, inode->i_size)) {
+		ret = -errno;
+		erofs_err("failed to set file size: %s (%s)",
+			  fsckcfg.extract_path, strerror(-ret));
+	}
 	close(fd);
 	return ret;
 }
-- 
2.55.0