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
When a hdc is created no initial or default objects are created
therefore can the first call of gdi_SelectObject return NULL.
Because of this checking the return value of gdi_SelectObject failed
for newly create hdc causing errors (disconnects).
Since all types of HGDIOBJECT are handled and the return value of
gdi_SelectObject isn't used the recently added checks were removed
again.
