New general output functions for checks - #1483

Dear Monitoring Team,

I had a look at your checks and they are working great. I will introduce a new software, which the monitoring plugins will be one part of it. I have written some test cases for my own software and got some troubles. I have implemented my interpretation of the result to the general output specification: SERVICE STATUS: First line of output|First part of performance data|Second part of performance data
or
SERVICE STATUS: First line of output|First part of performance data|Second part of performance data
Third part of performance data|Fourth part of performance data ...

Some of the checks I have tested, does not take care about this behaviour. So I checked the code and tried to find the problem. I was successful and had a great look into the code from you.

As a general solution for this problem, I have done the following steps:

• Introduced general output functions for this use case
• print_singleline (int service_state, const char * msg, ...)
  Will print the output and returns to caller
• print_singleline_return (int service_state, const char * msg, ...)
  Will print the output, returns the service_state as a return value and returns to caller
• print_singleline_exit (int service_state, const char * msg, ...)
  Will print the output and exits program with service_state
• Declaration and implementation is done in utils.h and utils.c

The first step is to get this new function accepted by you.

After that, my next steps will be the following:

• Adapt sshutils.c and netutils.c to use this new functions
• Adapt some tests, to take care about the new output results
• Step by step change the checks to use this new functions and replace the usage* functions
• Take care about the tests, that they will be successfully tested

Best regards
Sven