--- /dev/null
+/*
+ * Copyright (C) Catalyst.Net Ltd 2020
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+/*
+ * Tests confirming lmdb's handling of the free space list in the presence
+ * of active and stale readers. A stale reader is a process that opens a
+ * read lock and then exits without releasing the lock.
+ *
+ * lmdb uses MVCC to maintain databased consistency, new copies of updated
+ * records are written to the database. The old entries are only
+ * reused when they are no longer referenced in a read transaction.
+ *
+ * The tests all update a single record multiple times
+ *
+ * If there is a read transaction or a stale reader lmdb will report
+ * out of space.
+ *
+ * If no read transaction and no stale reader, lmdb reclaims space from the
+ * free list.
+ */
+
+/*
+ * from cmocka.c:
+ * These headers or their equivalents should be included prior to
+ * including
+ * this header file.
+ *
+ * #include <stdarg.h>
+ * #include <stddef.h>
+ * #include <setjmp.h>
+ *
+ * This allows test applications to use custom definitions of C standard
+ * library functions and types.
+ *
+ */
+
+#include <stdarg.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <setjmp.h>
+#include <cmocka.h>
+
+#include <errno.h>
+#include <unistd.h>
+#include <talloc.h>
+#include <tevent.h>
+#include <ldb.h>
+#include <ldb_module.h>
+#include <ldb_private.h>
+#include <string.h>
+#include <ctype.h>
+
+#include <sys/wait.h>
+
+#include "ldb_tdb/ldb_tdb.h"
+#include "ldb_key_value/ldb_kv.h"
+
+#define DEFAULT_BE "mdb"
+
+#ifndef TEST_BE
+#define TEST_BE DEFAULT_BE
+#endif /* TEST_BE */
+
+const int RECORD_SIZE = 6144;
+const int ITERATIONS = 3;
+
+struct test_ctx {
+ struct tevent_context *ev;
+ struct ldb_context *ldb;
+
+ const char *dbfile;
+ const char *lockfile; /* lockfile is separate */
+
+ const char *dbpath;
+};
+
+static void unlink_old_db(struct test_ctx *test_ctx)
+{
+ int ret;
+
+ errno = 0;
+ ret = unlink(test_ctx->lockfile);
+ if (ret == -1 && errno != ENOENT) {
+ fail();
+ }
+
+ errno = 0;
+ ret = unlink(test_ctx->dbfile);
+ if (ret == -1 && errno != ENOENT) {
+ fail();
+ }
+}
+
+static int noconn_setup(void **state)
+{
+ struct test_ctx *test_ctx;
+
+ test_ctx = talloc_zero(NULL, struct test_ctx);
+ assert_non_null(test_ctx);
+
+ test_ctx->ev = tevent_context_init(test_ctx);
+ assert_non_null(test_ctx->ev);
+
+ test_ctx->ldb = ldb_init(test_ctx, test_ctx->ev);
+ assert_non_null(test_ctx->ldb);
+
+ test_ctx->dbfile = talloc_strdup(test_ctx, "lmdb_free_list_test.ldb");
+ assert_non_null(test_ctx->dbfile);
+
+ test_ctx->lockfile =
+ talloc_asprintf(test_ctx, "%s-lock", test_ctx->dbfile);
+ assert_non_null(test_ctx->lockfile);
+
+ test_ctx->dbpath =
+ talloc_asprintf(test_ctx, TEST_BE "://%s", test_ctx->dbfile);
+ assert_non_null(test_ctx->dbpath);
+
+ unlink_old_db(test_ctx);
+ *state = test_ctx;
+ return 0;
+}
+
+static int noconn_teardown(void **state)
+{
+ struct test_ctx *test_ctx =
+ talloc_get_type_abort(*state, struct test_ctx);
+
+ unlink_old_db(test_ctx);
+ talloc_free(test_ctx);
+ return 0;
+}
+
+static int setup(void **state)
+{
+ struct test_ctx *test_ctx;
+ int ret;
+ struct ldb_ldif *ldif;
+ const char *index_ldif = "dn: @INDEXLIST\n"
+ "@IDXGUID: objectUUID\n"
+ "@IDX_DN_GUID: GUID\n"
+ "\n";
+ /*
+ * Use a 64KiB DB for this test
+ */
+ const char *options[] = {"lmdb_env_size:65536", NULL};
+
+ noconn_setup((void **)&test_ctx);
+
+ ret = ldb_connect(test_ctx->ldb, test_ctx->dbpath, 0, options);
+ assert_int_equal(ret, 0);
+
+ while ((ldif = ldb_ldif_read_string(test_ctx->ldb, &index_ldif))) {
+ ret = ldb_add(test_ctx->ldb, ldif->msg);
+ assert_int_equal(ret, LDB_SUCCESS);
+ }
+ *state = test_ctx;
+ return 0;
+}
+
+static int teardown(void **state)
+{
+ struct test_ctx *test_ctx =
+ talloc_get_type_abort(*state, struct test_ctx);
+ noconn_teardown((void **)&test_ctx);
+ return 0;
+}
+
+static struct ldb_kv_private *get_ldb_kv(struct ldb_context *ldb)
+{
+ void *data = NULL;
+ struct ldb_kv_private *ldb_kv = NULL;
+
+ data = ldb_module_get_private(ldb->modules);
+ assert_non_null(data);
+
+ ldb_kv = talloc_get_type(data, struct ldb_kv_private);
+ assert_non_null(ldb_kv);
+
+ return ldb_kv;
+}
+
+static int parse(struct ldb_val key, struct ldb_val data, void *private_data)
+{
+ struct ldb_val *read = private_data;
+
+ /* Yes, we leak this. That is OK */
+ read->data = talloc_size(NULL, data.length);
+ assert_non_null(read->data);
+
+ memcpy(read->data, data.data, data.length);
+ read->length = data.length;
+ return LDB_SUCCESS;
+}
+
+/*
+ * This test has the same structure as the test_free_list_read_lock
+ * except the parent process does not keep the read lock open while the
+ * child process is performing an update.
+ */
+static void test_free_list_no_read_lock(void **state)
+{
+ int ret;
+ struct test_ctx *test_ctx =
+ talloc_get_type_abort(*state, struct test_ctx);
+ struct ldb_kv_private *ldb_kv = get_ldb_kv(test_ctx->ldb);
+ struct ldb_val key;
+ struct ldb_val val;
+
+ const char *KEY1 = "KEY01";
+
+ /*
+ * Pipes etc to co-ordinate the processes
+ */
+ int to_child[2];
+ int to_parent[2];
+ char buf[2];
+ pid_t pid;
+ size_t i;
+
+ TALLOC_CTX *tmp_ctx;
+ tmp_ctx = talloc_new(test_ctx);
+ assert_non_null(tmp_ctx);
+
+ ret = pipe(to_child);
+ assert_int_equal(ret, 0);
+ ret = pipe(to_parent);
+ assert_int_equal(ret, 0);
+ /*
+ * Now fork a new process
+ */
+
+ pid = fork();
+ if (pid == 0) {
+ /*
+ * Child process
+ */
+
+ struct ldb_context *ldb = NULL;
+ close(to_child[1]);
+ close(to_parent[0]);
+
+ /*
+ * Wait for the parent to get ready.
+ */
+ ret = read(to_child[0], buf, 2);
+ assert_int_equal(ret, 2);
+
+ ldb = ldb_init(test_ctx, test_ctx->ev);
+ assert_non_null(ldb);
+
+ ret = ldb_connect(ldb, test_ctx->dbpath, 0, NULL);
+ assert_int_equal(ret, LDB_SUCCESS);
+
+ ldb_kv = get_ldb_kv(ldb);
+ assert_non_null(ldb_kv);
+ /*
+ * Add a record to the database
+ */
+ key.data = (uint8_t *)talloc_strdup(tmp_ctx, KEY1);
+ key.length = strlen(KEY1) + 1;
+ val.data = talloc_zero_size(tmp_ctx, RECORD_SIZE);
+ assert_non_null(val.data);
+ memset(val.data, 'x', RECORD_SIZE);
+ val.length = RECORD_SIZE;
+ /*
+ * Do more iterations than when a read lock, stale reader
+ * active to confirm that the space is being re-used.
+ */
+ for (i = 0; i < ITERATIONS * 10; i++) {
+ ret = ldb_kv->kv_ops->begin_write(ldb_kv);
+ assert_int_equal(ret, LDB_SUCCESS);
+
+ ret = ldb_kv->kv_ops->store(ldb_kv, key, val, 0);
+ assert_int_equal(ret, LDB_SUCCESS);
+
+ ret = ldb_kv->kv_ops->finish_write(ldb_kv);
+ assert_int_equal(ret, LDB_SUCCESS);
+ }
+
+ /*
+ * Signal the parent that we've done the updates
+ */
+ ret = write(to_parent[1], "GO", 2);
+ assert_int_equal(ret, 2);
+ exit(0);
+ }
+
+ close(to_child[0]);
+ close(to_parent[1]);
+
+ /*
+ * Begin a read transaction
+ */
+ ret = ldb_kv->kv_ops->lock_read(test_ctx->ldb->modules);
+ assert_int_equal(ret, LDB_SUCCESS);
+
+ /*
+ * Now close it
+ */
+ ret = ldb_kv->kv_ops->unlock_read(test_ctx->ldb->modules);
+ assert_int_equal(ret, LDB_SUCCESS);
+
+ /*
+ * Signal the child process
+ */
+ ret = write(to_child[1], "GO", 2);
+ assert_int_equal(2, ret);
+
+ /*
+ * Wait for the child process to update the record
+ */
+ ret = read(to_parent[0], buf, 2);
+ assert_int_equal(2, ret);
+
+ /*
+ * Begin a read transaction
+ */
+ ret = ldb_kv->kv_ops->lock_read(test_ctx->ldb->modules);
+ assert_int_equal(ret, LDB_SUCCESS);
+ /*
+ * read the record
+ * and close the transaction
+ */
+ key.data = (uint8_t *)talloc_strdup(tmp_ctx, KEY1);
+ key.length = strlen(KEY1) + 1;
+
+ ret = ldb_kv->kv_ops->fetch_and_parse(ldb_kv, key, parse, &val);
+ assert_int_equal(ret, LDB_SUCCESS);
+
+ ret = ldb_kv->kv_ops->unlock_read(test_ctx->ldb->modules);
+ assert_int_equal(ret, LDB_SUCCESS);
+
+ close(to_child[1]);
+ close(to_parent[0]);
+ TALLOC_FREE(tmp_ctx);
+}
+
+/*
+ * This test has the same structure as the test_free_list_read_lock
+ * except the parent process keeps the read lock open while the
+ * child process is performing an update.
+ */
+static void test_free_list_read_lock(void **state)
+{
+ int ret;
+ struct test_ctx *test_ctx =
+ talloc_get_type_abort(*state, struct test_ctx);
+ struct ldb_kv_private *ldb_kv = get_ldb_kv(test_ctx->ldb);
+ struct ldb_val key;
+ struct ldb_val val;
+
+ const char *KEY1 = "KEY01";
+
+ /*
+ * Pipes etc to co-ordinate the processes
+ */
+ int to_child[2];
+ int to_parent[2];
+ char buf[2];
+ pid_t pid;
+ size_t i;
+
+ TALLOC_CTX *tmp_ctx;
+ tmp_ctx = talloc_new(test_ctx);
+ assert_non_null(tmp_ctx);
+
+ ret = pipe(to_child);
+ assert_int_equal(ret, 0);
+ ret = pipe(to_parent);
+ assert_int_equal(ret, 0);
+ /*
+ * Now fork a new process
+ */
+
+ pid = fork();
+ if (pid == 0) {
+ /*
+ * Child process
+ */
+
+ struct ldb_context *ldb = NULL;
+ close(to_child[1]);
+ close(to_parent[0]);
+
+ /*
+ * Wait for the transaction to start
+ */
+ ret = read(to_child[0], buf, 2);
+ assert_int_equal(ret, 2);
+
+ ldb = ldb_init(test_ctx, test_ctx->ev);
+ assert_non_null(ldb);
+
+ ret = ldb_connect(ldb, test_ctx->dbpath, 0, NULL);
+ assert_int_equal(ret, LDB_SUCCESS);
+
+ ldb_kv = get_ldb_kv(ldb);
+ assert_non_null(ldb_kv);
+ /*
+ * Add a record to the database
+ */
+ key.data = (uint8_t *)talloc_strdup(tmp_ctx, KEY1);
+ key.length = strlen(KEY1) + 1;
+ val.data = talloc_zero_size(tmp_ctx, RECORD_SIZE);
+ assert_non_null(val.data);
+ memset(val.data, 'x', RECORD_SIZE);
+ val.length = RECORD_SIZE;
+ for (i = 0; i < ITERATIONS; i++) {
+ ret = ldb_kv->kv_ops->begin_write(ldb_kv);
+ assert_int_equal(ret, 0);
+ ret = ldb_kv->kv_ops->store(ldb_kv, key, val, 0);
+ if (ret == LDB_ERR_BUSY && i > 0) {
+ int rc = ldb_kv->kv_ops->abort_write(ldb_kv);
+ assert_int_equal(rc, LDB_SUCCESS);
+ break;
+ }
+ assert_int_equal(ret, LDB_SUCCESS);
+ ret = ldb_kv->kv_ops->finish_write(ldb_kv);
+ assert_int_equal(ret, LDB_SUCCESS);
+ }
+ assert_int_equal(ret, LDB_ERR_BUSY);
+ assert_int_not_equal(i, 0);
+
+ /*
+ * Begin a read transaction
+ */
+ ret = ldb_kv->kv_ops->lock_read(ldb->modules);
+ assert_int_equal(ret, LDB_SUCCESS);
+ /*
+ * read the record
+ * and close the transaction
+ */
+ key.data = (uint8_t *)talloc_strdup(tmp_ctx, KEY1);
+ key.length = strlen(KEY1) + 1;
+
+ ret = ldb_kv->kv_ops->fetch_and_parse(ldb_kv, key, parse, &val);
+ assert_int_equal(ret, LDB_SUCCESS);
+
+ ret = ldb_kv->kv_ops->unlock_read(ldb->modules);
+ assert_int_equal(ret, LDB_SUCCESS);
+
+ /*
+ * Signal the the parent that we've done the update
+ */
+ ret = write(to_parent[1], "GO", 2);
+ assert_int_equal(ret, 2);
+ exit(0);
+ }
+
+ close(to_child[0]);
+ close(to_parent[1]);
+
+ /*
+ * Begin a read transaction
+ */
+ ret = ldb_kv->kv_ops->lock_read(test_ctx->ldb->modules);
+ assert_int_equal(ret, LDB_SUCCESS);
+
+ /*
+ * Signal the child process
+ */
+ ret = write(to_child[1], "GO", 2);
+ assert_int_equal(ret, 2);
+
+ /*
+ * Wait for the child process to update the record
+ */
+ ret = read(to_parent[0], buf, 2);
+ assert_int_equal(ret, 2);
+
+ /*
+ * read the record
+ * and close the transaction
+ */
+ key.data = (uint8_t *)talloc_strdup(tmp_ctx, KEY1);
+ key.length = strlen(KEY1) + 1;
+
+ ret = ldb_kv->kv_ops->fetch_and_parse(ldb_kv, key, parse, &val);
+ assert_int_equal(ret, LDB_ERR_NO_SUCH_OBJECT);
+ ret = ldb_kv->kv_ops->unlock_read(test_ctx->ldb->modules);
+ assert_int_equal(ret, 0);
+
+ close(to_child[1]);
+ close(to_parent[0]);
+ TALLOC_FREE(tmp_ctx);
+}
+
+/*
+ * This tests forks a child process that opens a read lock and then
+ * exits. This results in a stale reader entry in the lmdb lock file.
+ */
+static void test_free_list_stale_reader(void **state)
+{
+ int ret;
+ struct test_ctx *test_ctx =
+ talloc_get_type_abort(*state, struct test_ctx);
+ struct ldb_kv_private *ldb_kv = get_ldb_kv(test_ctx->ldb);
+ struct ldb_val key;
+ struct ldb_val val;
+
+ const char *KEY1 = "KEY01";
+
+ /*
+ * Pipes etc to co-ordinate the processes
+ */
+ int to_child[2];
+ int to_parent[2];
+ char buf[2];
+ pid_t pid;
+ size_t i;
+
+ TALLOC_CTX *tmp_ctx;
+ tmp_ctx = talloc_new(test_ctx);
+ assert_non_null(tmp_ctx);
+
+ ret = pipe(to_child);
+ assert_int_equal(ret, 0);
+ ret = pipe(to_parent);
+ assert_int_equal(ret, 0);
+ /*
+ * Now fork a new process
+ */
+
+ pid = fork();
+ if (pid == 0) {
+ /*
+ * Child process
+ */
+
+ struct ldb_context *ldb = NULL;
+ close(to_child[1]);
+ close(to_parent[0]);
+
+ /*
+ * Wait for the parent to get ready
+ */
+ ret = read(to_child[0], buf, 2);
+ assert_int_equal(ret, 2);
+
+ ldb = ldb_init(test_ctx, test_ctx->ev);
+ assert_non_null(ldb);
+
+ ret = ldb_connect(ldb, test_ctx->dbpath, 0, NULL);
+ assert_int_equal(ret, LDB_SUCCESS);
+
+ ldb_kv = get_ldb_kv(ldb);
+ assert_non_null(ldb_kv);
+
+ /*
+ * Begin a read transaction
+ */
+ ret = ldb_kv->kv_ops->lock_read(ldb->modules);
+ assert_int_equal(ret, LDB_SUCCESS);
+
+ /*
+ * Now exit with out releasing the read lock
+ * this will result in a stale entry in the
+ * read lock table.
+ */
+
+ exit(0);
+ }
+
+ close(to_child[0]);
+ close(to_parent[1]);
+
+ /*
+ * Tell the child to start
+ */
+ ret = write(to_child[1], "GO", 2);
+ assert_int_equal(ret, 2);
+
+ close(to_child[1]);
+ close(to_parent[0]);
+
+ /*
+ * Now wait for the child process to complete
+ */
+ waitpid(pid, NULL, 0);
+
+ /*
+ * Add a record to the database
+ */
+ key.data = (uint8_t *)talloc_strdup(tmp_ctx, KEY1);
+ key.length = strlen(KEY1) + 1;
+ val.data = talloc_zero_size(tmp_ctx, RECORD_SIZE);
+ assert_non_null(val.data);
+ memset(val.data, 'x', RECORD_SIZE);
+ val.length = RECORD_SIZE;
+ for (i = 0; i < ITERATIONS; i++) {
+ ret = ldb_kv->kv_ops->begin_write(ldb_kv);
+ assert_int_equal(ret, LDB_SUCCESS);
+
+ ret = ldb_kv->kv_ops->store(ldb_kv, key, val, 0);
+ if (ret == LDB_ERR_BUSY && i > 0) {
+ int rc = ldb_kv->kv_ops->abort_write(ldb_kv);
+ assert_int_equal(rc, LDB_SUCCESS);
+ break;
+ }
+ assert_int_equal(ret, LDB_SUCCESS);
+
+ ret = ldb_kv->kv_ops->finish_write(ldb_kv);
+ assert_int_equal(ret, LDB_SUCCESS);
+ }
+ assert_int_equal(ret, LDB_ERR_BUSY);
+ assert_int_not_equal(i, 0);
+
+ /*
+ * Begin a read transaction
+ */
+ ret = ldb_kv->kv_ops->lock_read(test_ctx->ldb->modules);
+ assert_int_equal(ret, LDB_SUCCESS);
+ /*
+ * read the record
+ * and close the transaction
+ */
+ key.data = (uint8_t *)talloc_strdup(tmp_ctx, KEY1);
+ key.length = strlen(KEY1) + 1;
+
+ ret = ldb_kv->kv_ops->fetch_and_parse(ldb_kv, key, parse, &val);
+ assert_int_equal(ret, LDB_SUCCESS);
+
+ ret = ldb_kv->kv_ops->unlock_read(test_ctx->ldb->modules);
+ assert_int_equal(ret, LDB_SUCCESS);
+
+ TALLOC_FREE(tmp_ctx);
+}
+
+int main(int argc, const char **argv)
+{
+ const struct CMUnitTest tests[] = {
+ cmocka_unit_test_setup_teardown(
+ test_free_list_no_read_lock, setup, teardown),
+ cmocka_unit_test_setup_teardown(
+ test_free_list_read_lock, setup, teardown),
+ cmocka_unit_test_setup_teardown(
+ test_free_list_stale_reader, setup, teardown),
+ };
+
+ return cmocka_run_group_tests(tests, NULL, NULL);
+}
git.samba.org / gd / samba-autobuild / .git / commitdiff