new latrace code - global_sym/cofig-file/error-simulation

[Jiri Olsa]

hi,

I have some load of new latrace code to commit, so I thought I'd ask
you for review/ideas.. whatever is helpful, so I wont be the only one
to blame ;)

The reason for all the new code was the idea of error simulation via latrace.

Imagine you could specify what will certain function return and watch how
the application behave afterwards. For example having malloc to return NULL,
and simulate the allocation failure.

I started implementing this idea and it split into 3 parts:

global symbol place
- I needed global symbol place keeping all the info -
arguments/errors, so it'd be searched
just once

config file
- for error simulation I need to have configuration file, so I could specify
the details of simulation. That was the reason I added config file and added
support for some of the command line options.

error simulation
- the configuration is done in 2 parts.

First you specify in the latrace config file:
     what you want to simulate
     what functions to use for this
     how to run the program,
     how many times
     when to trigger the error..

Second there's configuration record for each function you want to use.
You specify
what return codes to use so far..

thats basicaly it so far.. :)

The current state is:
global_symbol
    - already in master branch
config file supprot
    - in config branch
    - should be complete, dont have any pending work for now
error simulation
    - in error branch
    - it is able to tun and simulate the error sequencionaly.. each run,
      the error is done in the next function call
    - it's very basic, it lacks the implementation of many configuration options
    - needs to watch and store traced program output (0/1/2 desc.)

I plan to put config file support into master branch soon and finish the error
simulation into some user usable state.. than I'd like to spin out 0.6 release..

any feedback is welcome :)

thanks,
jirka