This patch contains:
* checks for malloc return value + treat callers;
* modified malloc() + ZeroMemory() to calloc();
* misc fixes of micro errors seen during the code audit:
** some invalid checks in gcc.c, also there were some possible
integer overflow. This is interesting because at the end the data are parsed
and freed directly, so it's a vulnerability in some kind of dead code (at least
useless);
** fixed usage of GetComputerNameExA with just one call, when 2 were used
in misc places. According to MSDN GetComputerNameA() is supposed to return
an error when called with NULL;
** there were a bug in the command line parsing of shadow;
** in freerdp_dynamic_channel_collection_add() the size of array was multiplied
by 4 instead of 2 on resize
* top level GDI functions return 0 on error and != 0 otherwise but the
low level functions (16bpp.c, 8bpp.c 32bpp.c) which are called did it
exactly the other way around. Those were adapted.
* change gdi_InvalidateRegion to BOOL and check calls where appropriate
* integrate comments from pull request
