Server may crush when working with strings

[Mongi]

We are planning to use NetXMS with our custom push-type counters. All numeric counters seem to work well, but string one has some problems.

First of all, they are limited to 255 chars (according to database configuration). Moreover, they can cause server to crush due to lack of string NULL-terminator.

Way to reproduce:

1. Create DCI, Parameter:Test, Type: string; Origin: Push Agent
2. Excute:

C:\NetXMS\bin>nxpush.exe -H localhost -u user -P pass host.local:Test=123456789-123456789-123456789-123456789-123456789-123456789-123456789-123456789-123456789-123456789-123456789-123456789-123456789-123456789-123456789-123456789-123456789-123456789-123456789-123456789-123456789-123456789-123456789-123456789-123456789-123456789-123456789-123456789-123456789-123456789-123456789

(it is string with 300+ symbols)
3) Open "Last values" -- here you will see probably all of string
4) Open "Show history" -- here are 2 possibilities:
  a) server crush and you wont see anything
  b) you are lucky to see first 127 symbols and a bunch of garbage from server memory till first NULL-symbol

Server 1.0.4, Windows; DB: MSSQL

In spite of server crush, Is there a way work with strings longer than 127 symbols?

[alk]

Thank you for the report, we will check it ASAP.

[victor]

I have fixed this bug. Fix will be included in next release.

Best regards,
Victor

[Mongi]

Thanks for fast reply!

In addition, there is another problem with strings: some special chars get escaped on push, but never decoded in History.

For example:

C:\NetXMS\bin>nxpush.exe -H localhost -u user -P pass host.local:Test=\\//!@#$%^&*

Will be saved and showed as

#5C#5C//!@#23$#25&*

Also, if you add non-english characters, then they are showed as they were UTF8 encoded, so "ЙЦУКЕН" will become "РЦУКЕН". You are using simple varchar type in MSSQL in order to store values and it will be better to switch to nvarchar, or there are limitations from other DB engines?

[victor]

Character escaping bug fixed as well. I agree that we should switch to nvarchar from varchar in MS SQL, and we definitely will do that, but it's a major change, which will require careful examination of many SQL statements within existing code.

Best regards,
Victor

[Mongi]

Hello again!

I'm not sure weather it's a new bug or it has been already fixed, so I decided to write about it anyway.

When we try to set description of any DCI with non-english and non-russian language the description is saved as "?" symbols, for example: نوع محل or 测试服务 will be saved as "????".

Same behavior in "Parameter" field of DCI.

[victor]

It's because server not working with UNICODE texts. All texts coming from client (in UNICODE) converted to server's code page, which is set by CodePage parameter in netxmsd.conf. You can try to set codepage to UTF-8, but it may or may not work.

Best regards,
Victor