Revert "Configurable storage engine for Netdata agents: step 3 (#12892)" (#13171)

This reverts commit 100a12c6cc01222b1518e5e50d2147f592d8a111.

A couple parent/child startup/shutdown scenarios can lead to crashes.

4 files changed, 9 insertions, 27 deletions

diff --git a/daemon/analytics.c b/daemon/analytics.c
index c779253485..6c02561d0c 100644
--- a/daemon/analytics.c
+++ b/daemon/analytics.c
@@ -2,9 +2,6 @@
 
 #include "common.h"
 #include "buildinfo.h"
-#ifdef ENABLE_DBENGINE
-#include "database/engine/rrdengineapi.h"
-#endif
 
 struct analytics_data analytics_data;
 extern void analytics_exporting_connectors (BUFFER *b);
diff --git a/daemon/global_statistics.c b/daemon/global_statistics.c
index a5f7094d54..b5740b176f 100644
--- a/daemon/global_statistics.c
+++ b/daemon/global_statistics.c
@@ -1,9 +1,6 @@
 // SPDX-License-Identifier: GPL-3.0-or-later
 
 #include "common.h"
-#ifdef ENABLE_DBENGINE
-#include "database/engine/rrdengineapi.h"
-#endif
 
 #define GLOBAL_STATS_RESET_WEB_USEC_MAX 0x01
 
@@ -459,7 +456,7 @@ static void dbengine_statistics_charts(void) {
 
         rrdhost_foreach_read(host) {
             if (host->rrd_memory_mode == RRD_MEMORY_MODE_DBENGINE && !rrdhost_flag_check(host, RRDHOST_FLAG_ARCHIVED)) {
-                if (host->rrdeng_ctx == host->rrdeng_ctx->engine->context) {
+                if (&multidb_ctx == host->rrdeng_ctx) {
                     if (counted_multihost_db)
                         continue; /* Only count multi-host DB once */
                     counted_multihost_db = 1;
diff --git a/daemon/main.c b/daemon/main.c
index fd5a42d96c..6a07add1c9 100644
--- a/daemon/main.c
+++ b/daemon/main.c
@@ -3,10 +3,6 @@
 #include "common.h"
 #include "buildinfo.h"
 #include "static_threads.h"
-#include "database/storage_engine.h"
-#ifdef ENABLE_DBENGINE
-#include "database/engine/rrdengineapi.h"
-#endif
 
 int netdata_zero_metrics_enabled;
 int netdata_anonymous_statistics_enabled;
@@ -58,18 +54,13 @@ void netdata_cleanup_and_exit(int ret) {
 
         // free the database
         info("EXIT: freeing database memory...");
-        for (STORAGE_ENGINE* eng = storage_engine_foreach_init(); eng; eng = storage_engine_foreach_next(eng)) {
-            if (eng->context)
-                eng->api.engine_ops.exit(eng->context);
-        }
-
+#ifdef ENABLE_DBENGINE
+        rrdeng_prepare_exit(&multidb_ctx);
+#endif
         rrdhost_free_all();
-        for (STORAGE_ENGINE* eng = storage_engine_foreach_init(); eng; eng = storage_engine_foreach_next(eng)) {
-            if (eng->context) {
-                eng->api.engine_ops.destroy(eng->context);
-                eng->context = NULL;
-            }
-        }
+#ifdef ENABLE_DBENGINE
+        rrdeng_exit(&multidb_ctx);
+#endif
     }
     sql_close_database();
 
diff --git a/daemon/unit_test.c b/daemon/unit_test.c
index 2dc92dcb21..35f8613a2b 100644
--- a/daemon/unit_test.c
+++ b/daemon/unit_test.c
@@ -1,9 +1,6 @@
 // SPDX-License-Identifier: GPL-3.0-or-later
 
 #include "common.h"
-#ifdef ENABLE_DBENGINE
-#include "database/engine/rrdengineapi.h"
-#endif
 
 static int check_number_printing(void) {
     struct {
@@ -1160,7 +1157,7 @@ int run_test(struct test *test)
     RRDSET *st = rrdset_create_localhost("netdata", name, name, "netdata", NULL, "Unit Testing", "a value", "unittest", NULL, 1
                                          , test->update_every, RRDSET_TYPE_LINE);
     RRDDIM *rd = rrddim_add(st, "dim1", NULL, test->multiplier, test->divisor, test->algorithm);
-
+    
     RRDDIM *rd2 = NULL;
     if(test->feed2)
         rd2 = rrddim_add(st, "dim2", NULL, test->multiplier, test->divisor, test->algorithm);
@@ -1176,7 +1173,7 @@ int run_test(struct test *test)
 
         if(c) {
             time_now += test->feed[c].microseconds;
-            fprintf(stderr, "    > %s: feeding position %lu, after %0.3f seconds (%0.3f seconds from start), delta " CALCULATED_NUMBER_FORMAT ", rate " CALCULATED_NUMBER_FORMAT "\n",
+            fprintf(stderr, "    > %s: feeding position %lu, after %0.3f seconds (%0.3f seconds from start), delta " CALCULATED_NUMBER_FORMAT ", rate " CALCULATED_NUMBER_FORMAT "\n", 
                 test->name, c+1,
                 (float)test->feed[c].microseconds / 1000000.0,
                 (float)time_now / 1000000.0,