files-backend: prefer "0" for write_in_full() error check

Commit 06f46f237a (avoid "write_in_full(fd, buf, len) !=
len" pattern, 2017-09-13) converted this callsite from:

  write_in_full(...) != 1

to

  write_in_full(...) < 0

But during the conflict resolution in c50424a6f0 (Merge
branch 'jk/write-in-full-fix', 2017-09-25), this morphed
into

  write_in_full(...) < 1

This behaves as we want, but we prefer to avoid modeling the
"less than length" error-check which can be subtly buggy, as
shown in efacf609c8 (config: avoid "write_in_full(fd, buf,
len) < len" pattern, 2017-09-13).

Signed-off-by: Jeff King <peff@peff.net>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/refs/files-backend.c b/refs/files-backend.c
index dac33628b37d4e19ea15e6706f1ab67c9b3a3e6c..e35c64c001d98582f72945b3af9ab3bc5261273b 100644 (file)
--- a/refs/files-backend.c
+++ b/refs/files-backend.c
@@ -3007,7 +3007,7 @@ static int files_reflog_expire(struct ref_store *ref_store,
                } else if (update &&
                           (write_in_full(get_lock_file_fd(&lock->lk),
                                oid_to_hex(&cb.last_kept_oid), GIT_SHA1_HEXSZ) < 0 ||
-                           write_str_in_full(get_lock_file_fd(&lock->lk), "\n") < 1 ||
+                           write_str_in_full(get_lock_file_fd(&lock->lk), "\n") < 0 ||
                            close_ref_gently(lock) < 0)) {
                        status |= error("couldn't write %s",
                                        get_lock_file_path(&lock->lk));