SMS Server Tools 3
This site is hosted by
Basic information:
Additional information:
Get SMS Server Tools 3:
Additional Options

 Sponsored links

Custom Search

 Visitor locations
 SMS Server Tools 3 Community
Welcome, Guest. Please login or register. Fri Sep 22, 2017 11:40
SMSTools3 Community » Bug reports Bottom

[PATCH] 3.1.21 truncates messages with certain Unicode code points

Login and Post Reply

Page:  1

Author Post
Jul 2017
Location: Vantaa, Finland
First of all, thank you for this great piece of software.
As part of setting up this system for a friend, I wanted to test how Unicode data is handled.

It turns out there are 2 bugs when receiving messages, and 1 when sending. Both will cause data to be truncated at the first encountered invalid character.

For receiving, any code point at U+8000 or above will cause truncation, if the char data type is signed and sizeof(unsigned int) > 2, which I believe should hold on most systems. The reason is that sign extension will take place here:

Because of the sign extension, we will have c>0xffff if sizeof(c) > 2, and this function will return 0, causing the string to be truncated.

Another problem for both receiving and sending is that UTF-16 data is not supported. UTF-16 is basically an extension of UCS2, allowing the code points U+10000 to U+FFFFF to be represented with two UCS2 code points, called surrogate pairs. The first pair is in the range 0xd800..0xdbff, and the second one is 0xdc00..0xdffff.

I fixed these problems. I registered on this forum only to report this bug and to submit my patch. I would have preferred to use email for this, but I did not find any address. So, I am posting my patch below (see more discussion after it):

The above patch includes some cleanup as well, mainly the addition of static linkage specifiers and const qualifiers.
For testing the patch, I used the following patch:

and the following test program that I wrote first so that I could reproduce the problem without having any hardware attached:

The test string that I used was from the "PDU" header of a received message. With that message, the output of the program would be as follows:

Without the patch applied, the string would be truncated at the first emoji (U+1F600), leaving the string "Koe ja toinen " (with a terminating space).

I would appreciate it if you could include this patch in the next smstools release.

May 2009
Location: Jyvรคskylรค, Finland
Thank you for publishing this bug report.

I will of course include the patch in the next version, as handling of code points >= U+8000 was incorrect, and UTF-16 was not supported at all.

A new version 3.1.22beta was already under construction and almost complete with some new features, but now I likely should release your patch as 3.1.22, and upcoming features as 3.1.23beta later. This may happen in the next few weeks, because now is the middle of summer.

Thanks again, and as the report was published here where reports are recommended to be shown, users of this software may use this patch before an official version is released.

Jul 2017
Location: Vantaa, Finland
Topic owner
Thank you for the prompt response and the decision to prepare an extra release with this fix.
My friend is planning to deploy the system in about a month. It is always easier when custom patches are not needed.

Login and Post Reply

Page:  1

SMSTools3 Community » Bug reports Top

Time in this board is UTC.  

Privacy Policy   SMS Server Tools 3 Copyright © Keijo Kasvi.