tdb2: open hook for implementing TDB_CLEAR_IF_FIRST

[ccan] / ccan / tdb2 / test / run-83-openhook.c

diff --git a/ccan/tdb2/test/run-83-openhook.c b/ccan/tdb2/test/run-83-openhook.c
new file mode 100644 (file)
index 0000000..c852793
--- /dev/null
+++ b/ccan/tdb2/test/run-83-openhook.c
@@ -0,0 +1,99 @@
+#include <ccan/tdb2/tdb.c>
+#include <ccan/tdb2/open.c>
+#include <ccan/tdb2/free.c>
+#include <ccan/tdb2/lock.c>
+#include <ccan/tdb2/io.c>
+#include <ccan/tdb2/hash.c>
+#include <ccan/tdb2/check.c>
+#include <ccan/tdb2/transaction.c>
+#include <ccan/tap/tap.h>
+#include <stdlib.h>
+#include <stdbool.h>
+#include <stdarg.h>
+#include <err.h>
+#include "external-agent.h"
+#include "logging.h"
+
+static enum TDB_ERROR clear_if_first(int fd, void *arg)
+{
+/* We hold a lock offset 63 always, so we can tell if anyone is holding it. */
+       struct flock fl;
+
+       if (arg != clear_if_first)
+               return TDB_ERR_CORRUPT;
+
+       fl.l_type = F_WRLCK;
+       fl.l_whence = SEEK_SET;
+       fl.l_start = 63;
+       fl.l_len = 1;
+
+       if (fcntl(fd, F_SETLK, &fl) == 0) {
+               /* We must be first ones to open it! */
+               diag("truncating file!");
+               if (ftruncate(fd, 0) != 0) {
+                       return TDB_ERR_IO;
+               }
+       }
+       fl.l_type = F_RDLCK;
+       if (fcntl(fd, F_SETLKW, &fl) != 0) {
+               return TDB_ERR_IO;
+       }
+       return TDB_SUCCESS;
+}
+
+int main(int argc, char *argv[])
+{
+       unsigned int i;
+       struct tdb_context *tdb;
+       struct agent *agent;
+       union tdb_attribute cif;
+       struct tdb_data key = tdb_mkdata("key", 3);
+       int flags[] = { TDB_DEFAULT, TDB_NOMMAP,
+                       TDB_CONVERT, TDB_NOMMAP|TDB_CONVERT };
+
+       cif.openhook.base.attr = TDB_ATTRIBUTE_OPENHOOK;
+       cif.openhook.base.next = &tap_log_attr;
+       cif.openhook.fn = clear_if_first;
+       cif.openhook.data = clear_if_first;
+
+       agent = prepare_external_agent();
+       plan_tests(sizeof(flags) / sizeof(flags[0]) * 13);
+       for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+               /* Create it */
+               tdb = tdb_open("run-83-openhook.tdb", flags[i],
+                              O_RDWR|O_CREAT|O_TRUNC, 0600, NULL);
+               ok1(tdb);
+               ok1(tdb_store(tdb, key, key, TDB_REPLACE) == 0);
+               tdb_close(tdb);
+
+               /* Now, open with CIF, should clear it. */
+               tdb = tdb_open("run-83-openhook.tdb", flags[i],
+                              O_RDWR, 0, &cif);
+               ok1(tdb);
+               ok1(!tdb_exists(tdb, key));
+               ok1(tdb_store(tdb, key, key, TDB_REPLACE) == 0);
+
+               /* Agent should not clear it, since it's still open. */
+               ok1(external_agent_operation(agent, OPEN_WITH_HOOK,
+                                            "run-83-openhook.tdb") == SUCCESS);
+               ok1(external_agent_operation(agent, FETCH, "key") == SUCCESS);
+               ok1(external_agent_operation(agent, CLOSE, "") == SUCCESS);
+
+               /* Still exists for us too. */
+               ok1(tdb_exists(tdb, key));
+
+               /* Close it, now agent should clear it. */
+               tdb_close(tdb);
+
+               ok1(external_agent_operation(agent, OPEN_WITH_HOOK,
+                                            "run-83-openhook.tdb") == SUCCESS);
+               ok1(external_agent_operation(agent, FETCH, "key") == FAILED);
+               ok1(external_agent_operation(agent, CLOSE, "") == SUCCESS);
+
+               ok1(tap_log_messages == 0);
+       }
+
+       free_external_agent(agent);
+       return exit_status();
+}
+