ntdb: don't munmap the database on every close.

Since we can have multiple openers, we should leave the mmap in place
for the other openers to use.  Enhance the test to check the bug (it
still works, because without mmap we fall back to read/write, but
performance would be terrible!).

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

2 files changed, 16 insertions, 13 deletions

diff --git a/lib/ntdb/open.c b/lib/ntdb/open.c
index 9de9e9b48c..56c97afe43 100644
--- a/lib/ntdb/open.c
+++ b/lib/ntdb/open.c
@@ -868,19 +868,19 @@ _PUBLIC_ int ntdb_close(struct ntdb_context *ntdb)
 		ntdb_transaction_cancel(ntdb);
 	}
 
-	if (ntdb->file->map_ptr) {
-		if (ntdb->flags & NTDB_INTERNAL)
-			ntdb->free_fn(ntdb->file->map_ptr, ntdb->alloc_data);
-		else
-			ntdb_munmap(ntdb->file);
-	}
-	if (ntdb->file) {
-		ntdb_lock_cleanup(ntdb);
-		if (--ntdb->file->refcnt == 0) {
-			ret = close(ntdb->file->fd);
-			ntdb->free_fn(ntdb->file->lockrecs, ntdb->alloc_data);
-			ntdb->free_fn(ntdb->file, ntdb->alloc_data);
+	ntdb_lock_cleanup(ntdb);
+	if (--ntdb->file->refcnt == 0) {
+		if (ntdb->file->map_ptr) {
+			if (ntdb->flags & NTDB_INTERNAL) {
+				ntdb->free_fn(ntdb->file->map_ptr,
+					      ntdb->alloc_data);
+			} else {
+				ntdb_munmap(ntdb->file);
+			}
 		}
+		ret = close(ntdb->file->fd);
+		ntdb->free_fn(ntdb->file->lockrecs, ntdb->alloc_data);
+		ntdb->free_fn(ntdb->file, ntdb->alloc_data);
 	}
 
 	/* Remove from tdbs list */
diff --git a/lib/ntdb/test/api-open-multiple-times.c b/lib/ntdb/test/api-open-multiple-times.c
index 217732d227..8663b8a24c 100644
--- a/lib/ntdb/test/api-open-multiple-times.c
+++ b/lib/ntdb/test/api-open-multiple-times.c
@@ -6,6 +6,7 @@
 #include <fcntl.h>
 #include <stdlib.h>
 #include "logging.h"
+#include "../private.h"
 
 int main(int argc, char *argv[])
 {
@@ -17,7 +18,7 @@ int main(int argc, char *argv[])
 	int flags[] = { NTDB_DEFAULT, NTDB_NOMMAP,
 			NTDB_CONVERT, NTDB_NOMMAP|NTDB_CONVERT };
 
-	plan_tests(sizeof(flags) / sizeof(flags[0]) * 28);
+	plan_tests(sizeof(flags) / sizeof(flags[0]) * 30);
 	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
 		ntdb = ntdb_open("run-open-multiple-times.ntdb",
 				 flags[i]|MAYBE_NOSYNC,
@@ -31,6 +32,7 @@ int main(int argc, char *argv[])
 				  O_RDWR|O_CREAT, 0600, &tap_log_attr);
 		ok1(ntdb_check(ntdb, NULL, NULL) == 0);
 		ok1(ntdb_check(ntdb2, NULL, NULL) == 0);
+		ok1((flags[i] & NTDB_NOMMAP) || ntdb2->file->map_ptr);
 
 		/* Store in one, fetch in the other. */
 		ok1(ntdb_store(ntdb, key, data, NTDB_REPLACE) == 0);
@@ -45,6 +47,7 @@ int main(int argc, char *argv[])
 		/* OK, now close first one, check second still good. */
 		ok1(ntdb_close(ntdb) == 0);
 
+		ok1((flags[i] & NTDB_NOMMAP) || ntdb2->file->map_ptr);
 		ok1(ntdb_store(ntdb2, key, data, NTDB_REPLACE) == 0);
 		ok1(ntdb_fetch(ntdb2, key, &d) == NTDB_SUCCESS);
 		ok1(ntdb_deq(d, data));