V3: Coverity / static analysis based cleanups

[Dirk Hohndel]

Third version of this series.
I addressed Jef's comments and dropped both patches that dealt with the
dc_buffer code as they did more damage than good.
Maybe I'll do a new set of patches just for the buffer code if I feel
bored later.

/D

[PATCH 01/12] Cleanup: correctly handle upper bound of array
[PATCH 02/12] Cleanup: avoid memory leaks
[PATCH 03/12] Cleanup: avoid memory leak
[PATCH 04/12] Cleanup: avoid memory leak
[PATCH 05/12] Cleanup: avoid memory leak
[PATCH 06/12] Cleanup: ensure string is 0 terminated
[PATCH 07/12] Cleanup: avoid undefined shift operation
[PATCH 08/12] Cleanup: remove dead code and return the correct return
[PATCH 09/12] Cleanup: check return value of ioctl()
[PATCH 10/12] Cleanup: consistently check return value of iostream
[PATCH 11/12] Cleanup: bail on error
[PATCH 12/12] Cleanup: remove confusing NULL check