- Added one macro to avoid dangling pointers
- Added two functions to perform NULL pointer check
since the allocation is not guaranteed by C library, although it
is a rare case, just for sanity
- Add NULL pointer check to brealloc() and bfree() and for sanity as well
Signed-off-by: Syrone Wong <wong.syrone@gmail.com>
errno is never set to zero by any system call or library function,
and it's programmer's resposibility to reset it before doing checks.
Otherwise the error might be misleading.
Signed-off-by: Syrone Wong <wong.syrone@gmail.com>