1 files changed, 136 insertions, 0 deletions
diff --git a/aclk/aclk_query_queue.c b/aclk/aclk_query_queue.c
new file mode 100644
index 0000000..9a45057
--- /dev/null
+++ b/aclk/aclk_query_queue.c
@@ -0,0 +1,136 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#include "aclk_query_queue.h"
+#include "aclk_query.h"
+#include "aclk_stats.h"
+
+static netdata_mutex_t aclk_query_queue_mutex = NETDATA_MUTEX_INITIALIZER;
+#define ACLK_QUEUE_LOCK netdata_mutex_lock(&aclk_query_queue_mutex)
+#define ACLK_QUEUE_UNLOCK netdata_mutex_unlock(&aclk_query_queue_mutex)
+
+static struct aclk_query_queue {
+    aclk_query_t head;
+    aclk_query_t tail;
+    int block_push;
+} aclk_query_queue = {
+    .head = NULL,
+    .tail = NULL,
+    .block_push = 0
+};
+
+static inline int _aclk_queue_query(aclk_query_t query)
+{
+    now_realtime_timeval(&query->created_tv);
+    query->created = now_realtime_usec();
+
+    ACLK_QUEUE_LOCK;
+    if (aclk_query_queue.block_push) {
+        ACLK_QUEUE_UNLOCK;
+        if(!netdata_exit)
+            error("Query Queue is blocked from accepting new requests. This is normally the case when ACLK prepares to shutdown.");
+        aclk_query_free(query);
+        return 1;
+    }
+    if (!aclk_query_queue.head) {
+        aclk_query_queue.head = query;
+        aclk_query_queue.tail = query;
+        ACLK_QUEUE_UNLOCK;
+        return 0;
+    }
+    // TODO deduplication
+    aclk_query_queue.tail->next = query;
+    aclk_query_queue.tail = query;
+    ACLK_QUEUE_UNLOCK;
+    return 0;
+
+}
+
+int aclk_queue_query(aclk_query_t query)
+{
+    int ret = _aclk_queue_query(query);
+    if (!ret) {
+        QUERY_THREAD_WAKEUP;
+        if (aclk_stats_enabled) {
+            ACLK_STATS_LOCK;
+            aclk_metrics_per_sample.queries_queued++;
+            ACLK_STATS_UNLOCK;
+        }
+    }
+    return ret;
+}
+
+aclk_query_t aclk_queue_pop(void)
+{
+    aclk_query_t ret;
+
+    ACLK_QUEUE_LOCK;
+    if (aclk_query_queue.block_push) {
+        ACLK_QUEUE_UNLOCK;
+        if(!netdata_exit)
+            error("POP Query Queue is blocked from accepting new requests. This is normally the case when ACLK prepares to shutdown.");
+        return NULL;
+    }
+
+    ret = aclk_query_queue.head;
+    if (!ret) {
+        ACLK_QUEUE_UNLOCK;
+        return ret;
+    }
+
+    aclk_query_queue.head = ret->next;
+    if (unlikely(!aclk_query_queue.head))
+        aclk_query_queue.tail = aclk_query_queue.head;
+    ACLK_QUEUE_UNLOCK;
+
+    ret->next = NULL;
+    return ret;
+}
+
+void aclk_queue_flush(void)
+{
+    aclk_query_t query = aclk_queue_pop();
+    while (query) {
+        aclk_query_free(query);
+        query = aclk_queue_pop();
+    };
+}
+
+aclk_query_t aclk_query_new(aclk_query_type_t type)
+{
+    aclk_query_t query = callocz(1, sizeof(struct aclk_query));
+    query->type = type;
+    return query;
+}
+
+void aclk_query_free(aclk_query_t query)
+{
+    switch (query->type) {
+    case HTTP_API_V2:
+        freez(query->data.http_api_v2.payload);
+        if (query->data.http_api_v2.query != query->dedup_id)
+            freez(query->data.http_api_v2.query);
+        break;
+
+    default:
+        break;
+    }
+
+    freez(query->dedup_id);
+    freez(query->callback_topic);
+    freez(query->msg_id);
+    freez(query);
+}
+
+void aclk_queue_lock(void)
+{
+    ACLK_QUEUE_LOCK;
+    aclk_query_queue.block_push = 1;
+    ACLK_QUEUE_UNLOCK;
+}
+
+void aclk_queue_unlock(void)
+{
+    ACLK_QUEUE_LOCK;
+    aclk_query_queue.block_push = 0;
+    ACLK_QUEUE_UNLOCK;
+}