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Hello,
I am removing all sprintf() function from my souce code as this function does not allow me to set the proper thread stack size. Does anyone have any function that implements this conversion?
Thanks Andre Moutinho
What do you mean by "proper stack size". sprintf() doesn't stop you from defining a stack size.
That the analysis tool can't perform a 100% analysis of call depth and stack need? Is that really a problem. Multiple calls to sprintf() with same formatting string should not have any larger difference in stack needs. You can "paint" the stack with magic marker bytes and then check the waterlevel to see how much stack your thread did consume with different parameters. If you have a processor with 128 bytes of RAM, you really have to consider every single byte when trying to decide on stack size. If you have an ARM chip with 8kB or 32kB or whatever, you can normally survive with 128 byte extra for a specific thread just to make sure.
If you are bored, you can always roll your own implementation to convert a floating point number to a text string - it isn't rocket sience.
Yes, the proper stack size because of the keil anaysis tool cannot perform 100% with functions such as sprintf(). I am already using the stack "paint" method but this is not a safe option for implementing complex systems on an embedded environment. I should have to run tests to guarantee the code is working but it is very complex and time consuming. I prefer trust on analysis tools instead. Implementing ftoa() is not difficult but I usually always try findining something ready instead of implementing everything. I have found some on google. Thanks Andre
Note that the use of sprintf() only affects tree branches using it.
It isn't too hard to get a good estimate of stack depth from sprintf() itself for relevant formatting strings and parameter sets.
The world have managed quit well with setting stack sizes without automatic tools at times when four bytes extra stack costed too much to waste - and where all your interrupts used the same stack. If you have only one thread with sprintf() then it really isn't too costly to add in a safety margin.