Merge pull request #1002 from alvarolobato/fix-connect-loop-188

Fix segfault and connect loop - PC/SDL2: defer jsonl/json to main thread

Author: fvanroie

src/hasp/hasp_dispatch.cpp

@@ -20,7 +20,17 @@
 #include <iostream>
 #include <fstream>
 #include <sstream>
+#include <queue>
+#include <mutex>
+#include <string>
 #include "../mqtt/hasp_mqtt.h"
+
+/* Deferred command queue: MQTT callback runs on Paho thread; jsonl/json handlers call LVGL
+ * (hasp_new_object) which is not thread-safe. Queue jsonl/json for processing on main thread.
+ * 64 is enough for burst layout + state; PC has plenty of memory. */
+#define DISPATCH_DEFERRED_QUEUE_MAX 64
+static std::queue<std::pair<std::string, std::string>> deferred_queue;
+static std::mutex deferred_mutex;
 #else
 #include "StringStream.h"
 #include "StreamUtils.h" // for exec ReadBufferingStream
@@ -463,6 +473,33 @@ void dispatch_topic_payload(const char* topic, const char* payload, bool update,
     dispatch_command(topic, (char*)payload, update, source); // dispatch as is
 }
 
+#if HASP_TARGET_PC
+void dispatch_defer_command(const char* topic, const char* payload)
+{
+    std::lock_guard<std::mutex> lock(deferred_mutex);
+    if(deferred_queue.size() >= DISPATCH_DEFERRED_QUEUE_MAX) {
+        (void)deferred_queue.front();
+        deferred_queue.pop(); // drop oldest
+    }
+    deferred_queue.push({std::string(topic), std::string(payload)});
+}
+
+void dispatch_process_deferred(void)
+{
+    std::pair<std::string, std::string> item;
+    for(;;) {
+        {
+            std::lock_guard<std::mutex> lock(deferred_mutex);
+            if(deferred_queue.empty()) break;
+            item = deferred_queue.front();
+            deferred_queue.pop();
+        }
+        bool update = item.second.size() > 0;
+        dispatch_topic_payload(item.first.c_str(), item.second.c_str(), update, TAG_MQTT);
+    }
+}
+#endif
+
 // void dispatch_output_group_state(uint8_t groupid, uint16_t state)
 // {
 //     char payload[64];

src/hasp/hasp_dispatch.h

@@ -93,6 +93,12 @@ void dispatch_config(const char* topic, const char* payload, uint8_t source);
 
 void dispatch_normalized_group_values(hasp_update_value_t& value);
 
+#if HASP_TARGET_PC
+/* Defer json/jsonl from MQTT thread to main (LVGL) thread to avoid segfault (PC/SDL2 only). */
+void dispatch_defer_command(const char* topic, const char* payload);
+void dispatch_process_deferred(void);
+#endif
+
 void dispatch_state_subtopic(const char* subtopic, const char* payload);
 void dispatch_state_eventid(const char* topic, hasp_event_t eventid);
 void dispatch_state_brightness(const char* topic, hasp_event_t eventid, int32_t val);

src/main.cpp

@@ -172,6 +172,11 @@ IRAM_ATTR void loop()
     }
 #endif
 
+#if HASP_TARGET_PC
+    /* Process jsonl/json commands deferred from MQTT thread (LVGL not thread-safe on PC). */
+    dispatch_process_deferred();
+#endif
+
 #if HASP_USE_LVGL_TASK == 0
     guiLoop();
 #endif

src/mqtt/hasp_mqtt_paho_async.cpp

@@ -44,7 +44,7 @@ const char FP_CONFIG_GROUP[] PROGMEM = "group";
 
 #include "hasp_mqtt.h" // functions to implement here
 
-#include "hasp/hasp_dispatch.h" // for dispatch_topic_payload
+#include "hasp/hasp_dispatch.h" // for dispatch_topic_payload, dispatch_defer_command
 #include "hasp_debug.h"         // for logging
 
 #if !defined(_WIN32)
@@ -206,6 +206,11 @@ static void mqtt_message_cb(char* topic, char* payload, size_t length)
             // LOG_TRACE(TAG_MQTT, F("ignoring LWT = online"));
         }
     } else {
+        // On PC, jsonl/json handlers call LVGL from MQTT thread -> segfault. Defer to main thread.
+        if(!strcmp(topic, "command/jsonl") || !strcmp(topic, "command/json")) {
+            dispatch_defer_command(topic, payload);
+            return;
+        }
         dispatch_mtx.lock();
         dispatch_topic_payload(topic, (const char*)payload, length > 0, TAG_MQTT);
         dispatch_mtx.unlock();

user_setups/darwin/darwin_headless.ini

@@ -6,6 +6,7 @@ extra_scripts =
   tools/linux_build_extra.py
 build_flags =
   ${env.build_flags}
+  -std=c++14
   -D HASP_MODEL="MacOS Headless"
   -D HASP_TARGET_PC=1
 

user_setups/linux/linux_fbdev.ini

@@ -4,6 +4,7 @@ extra_scripts =
   tools/linux_build_extra.py
 build_flags =
   ${env.build_flags}
+  -std=c++14
   -D HASP_MODEL="Linux App"
   -D HASP_TARGET_PC=1
 

user_setups/linux/linux_headless.ini

@@ -4,6 +4,7 @@ extra_scripts =
   tools/linux_build_extra.py
 build_flags =
   ${env.build_flags}
+  -std=c++14
   -D HASP_MODEL="Linux Headless"
   -D HASP_TARGET_PC=1