From d766a3635a4a636b5792df9c7c5a1cf80f1bbde1 Mon Sep 17 00:00:00 2001
From: Martin Preuss <martin@aquamaniac.de>
Date: Sat, 8 Jul 2023 01:58:43 +0200
Subject: [PATCH] mqtt: started working on 2nd generation msgio implementation.

---
 aqhome/mqtt/0BUILD           |   2 +
 aqhome/mqtt/endpoint2_mqtt.c | 107 +++++++++++++++++++++++++++++++++++
 aqhome/mqtt/endpoint2_mqtt.h |  40 +++++++++++++
 3 files changed, 149 insertions(+)
 create mode 100644 aqhome/mqtt/endpoint2_mqtt.c
 create mode 100644 aqhome/mqtt/endpoint2_mqtt.h

diff --git a/aqhome/mqtt/0BUILD b/aqhome/mqtt/0BUILD
index acca051..70d304b 100644
--- a/aqhome/mqtt/0BUILD
+++ b/aqhome/mqtt/0BUILD
@@ -46,6 +46,7 @@
   
     <headers dist="true" install="$(pkgincludedir)/ipc" >
       endpoint_mqttc.h
+      endpoint2_mqtt.h
       msg_mqtt.h
       msg_mqtt_connect.h
       msg_mqtt_connack.h
@@ -65,6 +66,7 @@
       $(local/typefiles)
 
       endpoint_mqttc.c
+      endpoint2_mqtt.c
       msg_mqtt.c
       msg_mqtt_connect.c
       msg_mqtt_connack.c
diff --git a/aqhome/mqtt/endpoint2_mqtt.c b/aqhome/mqtt/endpoint2_mqtt.c
new file mode 100644
index 0000000..7020fa2
--- /dev/null
+++ b/aqhome/mqtt/endpoint2_mqtt.c
@@ -0,0 +1,107 @@
+/****************************************************************************
+ * This file is part of the project AqHome.
+ * AqHome (c) by 2023 Martin Preuss, all rights reserved.
+ *
+ * The license for this file can be found in the file COPYING which you
+ * should have received along with this file.
+ ****************************************************************************/
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include "./endpoint2_mqtt.h"
+
+#include <gwenhywfar/endpoint2_msgio.h>
+#include <gwenhywfar/debug.h>
+
+
+
+/* ------------------------------------------------------------------------------------------------
+ * forward declarations
+ * ------------------------------------------------------------------------------------------------
+ */
+
+static int _getBytesNeededForMessage(GWEN_MSG_ENDPOINT2 *ep, GWEN_MSG *msg);
+static int _calcAndSetPayloadSizeAndOffset(GWEN_MSG *msg);
+
+
+
+/* ------------------------------------------------------------------------------------------------
+ * implementations
+ * ------------------------------------------------------------------------------------------------
+ */
+
+
+void AQH_MqttEndpoint2_Extend(GWEN_MSG_ENDPOINT2 *ep)
+{
+  if (ep) {
+    GWEN_MsgIoEndpoint2_SetGetNeededBytesFn(ep, _getBytesNeededForMessage);
+  }
+}
+
+
+
+int _getBytesNeededForMessage(GWEN_UNUSED GWEN_MSG_ENDPOINT2 *ep, GWEN_MSG *msg)
+{
+  uint32_t bytesInMsg;
+
+  bytesInMsg=GWEN_Msg_GetBytesInBuffer(msg);
+  if (bytesInMsg<2) {
+    DBG_INFO(AQH_LOGDOMAIN, "Header not yet complete");
+    return (int) (2-bytesInMsg);
+  }
+  if (!(GWEN_Msg_GetFlags(msg) & GWEN_MSG_FLAGS_PAYLOADINFO_SET))
+    _calcAndSetPayloadSizeAndOffset(msg);
+
+  if (GWEN_Msg_GetFlags(msg) & GWEN_MSG_FLAGS_PAYLOADINFO_SET) {
+    uint32_t msgLength;
+
+    msgLength=GWEN_Msg_GetParsedPayloadOffset(msg)+GWEN_Msg_GetParsedPayloadSize(msg);
+    return (int)(msgLength-bytesInMsg);
+  }
+  else {
+    DBG_INFO(AQH_LOGDOMAIN, "Size field not complete, requesting another byte");
+    return 1;
+  }
+}
+
+
+
+int _calcAndSetPayloadSizeAndOffset(GWEN_MSG *msg)
+{
+  int remainingBytesInBuffer;
+  uint32_t mqttRemainingLength=0;
+
+  remainingBytesInBuffer=GWEN_Msg_GetBytesInBuffer(msg);
+  if (remainingBytesInBuffer>1) {
+    const uint8_t *ptr;
+    int idx;
+    int shift=0;
+
+    ptr=GWEN_Msg_GetConstBuffer(msg);
+    idx=1;
+    remainingBytesInBuffer--;
+    while(remainingBytesInBuffer) {
+      uint8_t len;
+
+      len=ptr[idx];
+      mqttRemainingLength+=(len & 0x7f)<<shift;
+      if (!(len & 0x80)) {
+        /* last byte of size */
+        GWEN_Msg_SetParsedPayloadSize(msg, mqttRemainingLength);
+        GWEN_Msg_SetParsedPayloadOffset(msg, idx+1); /* payload follows at next byte */
+        GWEN_Msg_AddFlags(msg, GWEN_MSG_FLAGS_PAYLOADINFO_SET);
+        return 1; /* size successfully determined */
+      }
+      shift+=7;
+      idx++;
+      remainingBytesInBuffer--;
+    }
+  }
+  return 0;
+}
+
+
+
+
diff --git a/aqhome/mqtt/endpoint2_mqtt.h b/aqhome/mqtt/endpoint2_mqtt.h
new file mode 100644
index 0000000..e8fa9c2
--- /dev/null
+++ b/aqhome/mqtt/endpoint2_mqtt.h
@@ -0,0 +1,40 @@
+/****************************************************************************
+ * This file is part of the project Gwenhywfar.
+ * Gwenhywfar (c) by 2023 Martin Preuss, all rights reserved.
+ *
+ * The license for this file can be found in the file COPYING which you
+ * should have received along with this file.
+ ****************************************************************************/
+
+#ifndef AQH_ENDPOINT2_MQTTC_H
+#define AQH_ENDPOINT2_MQTTC_H
+
+
+#include <aqhome/api.h>
+
+#include <gwenhywfar/endpoint2.h>
+
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+
+/**
+ * Extends the given endpoint to support MQTT messages. It expects the function GWEN_MsgIoEndpoint2_Extend() to have been called
+ * beforehand.
+ */
+AQHOME_API void AQH_MqttEndpoint2_Extend(GWEN_MSG_ENDPOINT2 *ep);
+
+
+
+
+
+#ifdef __cplusplus
+}
+#endif
+
+
+#endif
+
+