tdb: make TDB_NOSYNC merely disable sync.

(As suggested by Stefan Metzmacher, based on the change to ntdb.)

Since commit ec96ea690edbe3398d690b4a953d487ca1773f1c, we handle the case
where a process dies during a transaction commit.  Unfortunately, TDB_NOSYNC
means this no longer works, as it disables the recovery area as well as the
actual msync/fsync.  We should do everything except the syncs.

This also means we can do a complete test with $TDB_NO_FSYNC set; just
to get more complete coverage, we disable it explicitly for one test
(where we override the actual sync calls anyway).

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

1 files changed, 12 insertions, 2 deletions

diff --git a/lib/tdb/test/run-transaction-expand.c b/lib/tdb/test/run-transaction-expand.c
index 3b79dbb6ea..bc22d2b53e 100644
--- a/lib/tdb/test/run-transaction-expand.c
+++ b/lib/tdb/test/run-transaction-expand.c
@@ -1,8 +1,10 @@
 #include "../common/tdb_private.h"
 
-/* Speed up the tests: setting TDB_NOSYNC removed recovery altogether. */
+/* Speed up the tests, but do the actual sync tests. */
+static unsigned int sync_counts = 0;
 static inline int fake_fsync(int fd)
 {
+	sync_counts++;
 	return 0;
 }
 #define fsync fake_fsync
@@ -10,6 +12,7 @@ static inline int fake_fsync(int fd)
 #ifdef MS_SYNC
 static inline int fake_msync(void *addr, size_t length, int flags)
 {
+	sync_counts++;
 	return 0;
 }
 #define msync fake_msync
@@ -18,6 +21,7 @@ static inline int fake_msync(void *addr, size_t length, int flags)
 #ifdef HAVE_FDATASYNC
 static inline int fake_fdatasync(int fd)
 {
+	sync_counts++;
 	return 0;
 }
 #define fdatasync fake_fdatasync
@@ -59,7 +63,10 @@ int main(int argc, char *argv[])
 	struct tdb_record rec;
 	tdb_off_t off;
 
-	plan_tests(4);
+	/* Do *not* suppress sync for this test; we do it ourselves. */
+	unsetenv("TDB_NO_FSYNC");
+
+	plan_tests(5);
 	tdb = tdb_open_ex("run-transaction-expand.tdb",
 			  1024, TDB_CLEAR_IF_FIRST,
 			  O_CREAT|O_TRUNC|O_RDWR, 0600, &taplogctx, NULL);
@@ -103,6 +110,9 @@ int main(int argc, char *argv[])
 
 	/* We should only be about 4 times larger than largest record. */
 	ok1(tdb->map_size < 5 * i * getpagesize());
+
+	/* We should have synchronized multiple times. */
+	ok1(sync_counts);
 	tdb_close(tdb);
 	free(data.dptr);