MQTT Apps on Linux Host (IDFGH-16163)

[prabhu-yu]

Description

Running ESP-IDF apps in Linux Host is great time saver(please see the link below).
There is ongoing effort for this.
However, when I try to run mqtt on Linux, build fails due to an undefined function.(please see the build output below)
So I have added that function for linux port.
https://docs.espressif.com/projects/esp-idf/en/stable/esp32/api-guides/host-apps.html

Please suggest improvements to this PR.

Log:

Compilation failure due to undefined function esp_timer_get_time
/usr/bin/ld: esp-idf/mqtt/libmqtt.a(platform_esp32_idf.c.o): in function `platform_tick_get_ms':
/home/p/esp/esp-idf-v5.5/components/mqtt/esp-mqtt/lib/platform_esp32_idf.c:53:(.text.platform_tick_get_ms+0x9): undefined reference to `esp_timer_get_time'
collect2: error: ld returned 1 exit status
ninja: build stopped: subcommand failed.
ninja failed with exit code 1, output of the command is in the /home/p/gitlab/sw/esp32-cpp/source/build/log/idf_py_stderr_output_3888355 and /home/p/gitlab/sw/esp32-cpp/source/build/log/idf_py_stdout_output_3888355

Related

Testing

Tested on Ubuntu 24.04.2 LTS
I could Build with mqtt and do publish a topic.
Log:

Executing action: all (aliases: build)
Running ninja in directory /home/p/gitlab/sw/esp32-cpp/source/build
Executing "ninja all"...
[1/4] cd /home/p/gitlab/sw/esp32-cpp/sourc...*****************************************"

Run log

Publishing from app running on linux host.

I (89867862) MQTT: Connected to MQTT Broker
I (89867862) MQTT: Subscribed to /device/1/input
I (89867862) MQTT: Publishing to topic: /device/1/output, message: Hello from ESP32
I (89867862) MQTT: return mqtt_event_handler()

Subscribed using mosquitto client.

--> mosquitto_sub -h broker.emqx.io -p 1883  -t  /device/1/output
Hello from ESP32

---

Checklist

Before submitting a Pull Request, please ensure the following:

• 🚨 This PR does not introduce breaking changes.
• All CI checks (GH Actions) pass.
• Documentation is updated as needed.
• Tests are updated or added as necessary.
• Code is well-commented, especially in complex areas.
• Git history is clean — commits are squashed to the minimum necessary.

[prabhu-yu]

Hi @david-cermak ,
May you please review this?

[david-cermak]

Hi @prabhu-yu

Thanks for checking out the host apps for with MQTT!

We have a host app running this MQTT library here: https://github.com/espressif/esp-protocols/tree/master/examples/mqtt
It just uses some linux-compat components that are not (yet) part of ESP-IDF.

[prabhu-yu]

Hi @prabhu-yu

Thanks for checking out the host apps for with MQTT!

We have a host app running this MQTT library here: https://github.com/espressif/esp-protocols/tree/master/examples/mqtt It just uses some linux-compat components that are not (yet) part of ESP-IDF.

Noted and Thank you @david-cermak .
(I will remove my PR)