From 332076b45b8a78f018ade2dfdc7e4279a56d49cc Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Mon, 3 Nov 2014 23:10:21 +0100 Subject: [PATCH 1/1] journald: also check journal file size to deduce if it is empty --- src/journal/journal-vacuum.c | 22 +++++++++++++++------- 1 file changed, 15 insertions(+), 7 deletions(-) diff --git a/src/journal/journal-vacuum.c b/src/journal/journal-vacuum.c index dbf5d2261..d141fe0ff 100644 --- a/src/journal/journal-vacuum.c +++ b/src/journal/journal-vacuum.c @@ -121,22 +121,30 @@ static void patch_realtime( } static int journal_file_empty(int dir_fd, const char *name) { - int r; - le64_t n_entries; _cleanup_close_ int fd; + struct stat st; + le64_t n_entries; + ssize_t n; fd = openat(dir_fd, name, O_RDONLY|O_CLOEXEC|O_NOFOLLOW|O_NONBLOCK); if (fd < 0) return -errno; - if (lseek(fd, offsetof(Header, n_entries), SEEK_SET) < 0) + if (fstat(fd, &st) < 0) return -errno; - r = read(fd, &n_entries, sizeof(n_entries)); - if (r != sizeof(n_entries)) - return r == 0 ? -EINVAL : -errno; + /* If an offline file doesn't even have a header we consider it empty */ + if (st.st_size < (off_t) sizeof(Header)) + return 1; + + /* If the number of entries is empty, we consider it empty, too */ + n = pread(fd, &n_entries, sizeof(n_entries), offsetof(Header, n_entries)); + if (n < 0) + return -errno; + if (n != sizeof(n_entries)) + return -EIO; - return le64toh(n_entries) == 0; + return le64toh(n_entries) <= 0; } int journal_directory_vacuum( -- 2.30.2