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hirotakaster
Fixed uninitialized value for this->ip
When connecting with a domain instead of an ip (or an ip in a string like "192.168.1.2"), the member variable this->ip was not initialized.
Later on, calling connect() would try to connect with this uninitialized ip and ignoring domain, thus connection was failing.
Hi, If you want to use IP address, use like this.
uint8_t server[] = { 192, 168.2, 1};
MQTT client(server, 1883, callback);
ip member is "uint8_t *ip" can't use for string ("192.168.1.2").
Hello,
I know I can use {192, 168, 1, 2} but I want to use "192.168.1.2" for several reasons:
- it's more visual, it looks more like an IP address
- if I get it from another source (like Particle.variable), it's easier to get a string and I don't want to add code to parse and check if it's an IP or a domain
- and last reason, it works
The patch I submitted really doesn't change anything if {192, 168, 1, 2} is used, but allows using the form "192.168.1.2" also.
regards, David
Hi @dguerizec ,
Oh, I see now what you want. That's right, you can use "192.168.1.2" string without no change on source code.
may be you call this function.
MQTT(char* domain, uint16_t port, void (*callback)(char*,uint8_t*,unsigned int)
first parameter domain can use for IP address string.
Exactly, but it doesn't work since commit 18b66728b969e13a63751c26ee417ee2d37216b1
Hi @dguerizec ,
Now I check and work fine. My environment is Particle Photon, firmware is default 0.5.3, MQTT library is 0.4.2 on Particle WebIDE.
Please check your environment.
Well, an uninitialized variable can work fine depending on the environment, but I assure you it doesn't work with mine :)
I'm not using the Particle IDE, but my own build system with firmware version 0.5.2 and MQTT library from github master.
My compiler is: arm-none-eabi-gcc (GNU Tools for ARM Embedded Processors) 4.9.3 20150529 (release) [ARM/embedded-4_9-branch revision 227977]
Maybe the main difference comes from the way I initialize my MQTT object.
I'm doing (here): MQTT mqtt = MQTT((char *)host, port, cb);
While you do: MQTT client((char *)host, port, cb);
I checked the code and there is one initialization of this->ip to NULL, but it's in the default constructor and I guess it's never called either way.
The initialization of this->ip should occur in initialize, even if ip is NULL. Otherwise this->ip could contain garbage and the test here will fail and try to connect to garbage IP.
Okay, but if merge this code part, I think the bottom of a problem is other reason.
MQTT mqtt = MQTT client("192.168.10.10", 1883, callback);
...
// in initialize function , this part call.
if (domain != NULL)
this->domain = domain;
...
// in MQTT.connect function, this TCP connection point is called.
if (ip == NULL)
result = _client->connect(this->domain.c_str(), this->port);
I think this point maybe problem. Following is on the source code.
Try to change to the following.
MQTT mqtt = MQTT client("192.168.10.10", 1883, callback);
...
// in initialize function , this part call.
if (domain != NULL)
this->domain = String(domain);
...
// in MQTT.connect function, this TCP connection point is called.
if (ip == NULL)
result = _client->connect(this->domain, this->port);
I checked like this now on the WebIDE lib environment, works well.
The problem I experienced is not on the domain part, but on the uninitialized ip member variable.
Another possibility for the fix could be to set ip to NULL in MQTT.h line 113: uint8_t *ip = NULL;
That's copy constructor is needed. But I don't define copy constructor.
Hello, I tested this on line 121 at MQTT.h file:
uint8_t *ip=NULL;
As on the connect() method you verify if the IP is NULL I think that it should be NULL by default at least that you set it properly on the constructor.
@hirotakaster Is it possible to close and merge this pr? What do you think?
