OdinWiFiInterface constructor has side-effects

[kylestein-arm]

Description

The construction of an instance of OdinWiFiInterface manipulates the system event queue in such a way that previous configuration is lost. In particular, when used with MbedCloudClient, the OdinWiFiInterface can cancel timers that were set up by the cloud client.

• Type: Bug
• Related issue: none known
• Priority: Major

---

Bug

Code behaves differently depending on when an OdinWiFiInterface is instantiated.
For instance

{
    OdinWiFiInterface wifi;
   
    ...

    MbedCloudClient _cloud_client;

    _cloud_client.setup(&wifi);
    ...
}

runs as expected,
But

{
    OdinWiFiInterface *wifi;
    MbedCloudClient _cloud_client;

    ...
    wifi = new OdinWiFiInterface();
    ...
     _cloud_client.setup(wifi);
    ...
}

results in a cloud client whose timers do not fire (for example it won't send keep-alive messages to the cloud)

Files using mbed-cloud-client-example-restricted to demonstrate this behavior are attached.

original.log
original.log - the trace debug log of mbed-cloud-client-example-restricted (unmodified).
easy-connect-patch.txt
easy-connect-patch.txt - patch for easy-connect.h
modified.log
modified.log - the trace debug log of mbed-cloud-client-example-restricted (with easy-connect.patch applied)

mbed-cloud-client-example-restricted uses the easy-connect library which instantiates a global OdinWiFiInterface at initialization. The patch modifies easy-connect, so that the OdinWiFiInterface is instantiated dynamically just before it is needed.

original.log shows the mbed cloud-client sending a keep-alive message as the result of a timer expiration
...
[DBG ][mClt]: M2MNsdlInterface::timer_expired - M2MTimerObserver::Registration - Send update registration
[DBG ][mClt]: M2MNsdlInterface::send_update_registration( lifetime 0)
...

These log messages are missing from modified.log.

Target
UBLOX_EVK_ODIN_W2

Toolchain:
GCC_ARM

Toolchain version:

mbed-cli version:
1.1.0

mbed-os sha:
fc18365 Merge pull request #4463 from ARMmbed/release-candidate

DAPLink version:

Expected behavior
Mbed cloud client should behave consistently regardless of when an OdinWiFiInterface is instantiated.

Actual behavior
Timers do not expire and thus Mbed cloud client does not send keep-alive messages in the case where an OdinWiFiInterface is instantiated after the cloud client.

Steps to reproduce
Apply easy-connect-patch.txt to the easy-connect library in mbed-cloud-client-example-restricted. Execute mbed-cloud-client-example-restricted

---

[0xc0170]

cc @andreaslarssonublox @andreaspeterssonublox

[andreaslarssonublox]

We have reproduced this and found the cause. The driver initializes the HAL ticks and configured the CPU clock but it has already been done by mbed OS/ST HAL. This will be fixed in the next release of the driver that most likely will be done this week.

[0xc0170]

This will be fixed in the next release of the driver that most likely will be done this week.

Great, waiting for the patch!

[ciarmcom]

ARM Internal Ref: MBOTRIAGE-165

[cmonr]

Closing since the referenced PR has long since been merged.