nfsdcld: add check/update functionality

Add functions to check whether a client is allowed to reclaim, and
update its timestamp in the DB if so. If either the query or update
fails, then the host is not allowed to reclaim state.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve Dickson <steved@redhat.com>

1 files changed, 73 insertions, 0 deletions

diff --git a/utils/nfsdcld/sqlite.c b/utils/nfsdcld/sqlite.c
index a198c34..01bba1a 100644
--- a/utils/nfsdcld/sqlite.c
+++ b/utils/nfsdcld/sqlite.c
@@ -287,3 +287,76 @@ out_err:
 	sqlite3_finalize(stmt);
 	return ret;
 }
+
+/*
+ * Is the given clname in the clients table? If so, then update its timestamp
+ * and return success. If the record isn't present, or the update fails, then
+ * return an error.
+ */
+int
+sqlite_check_client(const unsigned char *clname, const size_t namelen)
+{
+	int ret;
+	sqlite3_stmt *stmt = NULL;
+
+	ret = sqlite3_prepare_v2(dbh, "SELECT count(*) FROM clients WHERE "
+				      "id==?", -1, &stmt, NULL);
+	if (ret != SQLITE_OK) {
+		xlog(L_ERROR, "%s: unable to prepare update statement: %s",
+				__func__, sqlite3_errmsg(dbh));
+		goto out_err;
+	}
+
+	ret = sqlite3_bind_blob(stmt, 1, (const void *)clname, namelen,
+				SQLITE_STATIC);
+	if (ret != SQLITE_OK) {
+		xlog(L_ERROR, "%s: bind blob failed: %s",
+				__func__, sqlite3_errmsg(dbh));
+		goto out_err;
+	}
+
+	ret = sqlite3_step(stmt);
+	if (ret != SQLITE_ROW) {
+		xlog(L_ERROR, "%s: unexpected return code from select: %d",
+				__func__, ret);
+		goto out_err;
+	}
+
+	ret = sqlite3_column_int(stmt, 0);
+	xlog(D_GENERAL, "%s: select returned %d rows", ret);
+	if (ret != 1) {
+		ret = -EACCES;
+		goto out_err;
+	}
+
+	sqlite3_finalize(stmt);
+	stmt = NULL;
+	ret = sqlite3_prepare_v2(dbh, "UPDATE OR FAIL clients SET "
+				      "time=strftime('%s', 'now') WHERE id==?",
+				 -1, &stmt, NULL);
+	if (ret != SQLITE_OK) {
+		xlog(L_ERROR, "%s: unable to prepare update statement: %s",
+				__func__, sqlite3_errmsg(dbh));
+		goto out_err;
+	}
+
+	ret = sqlite3_bind_blob(stmt, 1, (const void *)clname, namelen,
+				SQLITE_STATIC);
+	if (ret != SQLITE_OK) {
+		xlog(L_ERROR, "%s: bind blob failed: %s",
+				__func__, sqlite3_errmsg(dbh));
+		goto out_err;
+	}
+
+	ret = sqlite3_step(stmt);
+	if (ret == SQLITE_DONE)
+		ret = SQLITE_OK;
+	else
+		xlog(L_ERROR, "%s: unexpected return code from update: %s",
+				__func__, sqlite3_errmsg(dbh));
+
+out_err:
+	xlog(D_GENERAL, "%s: returning %d", __func__, ret);
+	sqlite3_finalize(stmt);
+	return ret;
+}