[Bug 804355] Re: jot random number generator broken in batch jobs

[SaveTheRbtz]

Oh... Previous patch by any means was not supposed to go to mainline. It
was just dirty-hacky-PoC.

Here is our QA version. Changes:
* Switched to dpkg-source 3.0 (quilt) format
* Added dbg package
* Removed auto-generated files
* Applied arc4random patch

PS. I'm .rpm guy so I could messed up something there.
PPS. Could it be also backported to Lucid?


** Patch added: "0001-rng-Use-arc4random-insted-of-time-based-random.patch"
   https://bugs.launchpad.net/ubuntu/+source/athena-jot/+bug/804355/+attachment/2882511/+files/0001-rng-Use-arc4random-insted-of-time-based-random.patch

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https://bugs.launchpad.net/bugs/804355

Title:
  jot random number generator broken in batch jobs

Status in “athena-jot” package in Ubuntu:
  New

Bug description:
  jot -r generates same random numbers within one second time so it's
  unusable in batch jobs like shell scripts.

  There is code for initializing "random" seed:
      s = (randomize ? time(0) : STEP_DEF);
      /*... snip ....*/
      srand((int) s);

  Here is an example of this behavior:
  rbtz at rbtz-desktop:~$ date +%s; jot -r 1 0 10000000
  1309455778
  9981995
  rbtz at rbtz-desktop:~$ date +%s; jot -r 1 0 10000000
  1309455779
  2355993
  rbtz at rbtz-desktop:~$ date +%s; jot -r 1 0 10000000
  1309455779
  2355993
  rbtz at rbtz-desktop:~$ date +%s; jot -r 1 0 10000000
  1309455779
  2355993
  rbtz at rbtz-desktop:~$ date +%s; jot -r 1 0 10000000
  1309455780
  3745306
  rbtz at rbtz-desktop:~$ date +%s; jot -r 1 0 10000000
  1309455780
  3745306

  As fast fix pid can be added to seed
  srandom((int) s ^ (getpid()<<4));

  As good fix arc4random or similar mechanism can be used.

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