range_validbuf - range check buffer

       range_validbuf does some basic plausibility checks on the buffer buf[0..len-1].

       range_validbuf - range check buffer

       If the buffer is implausible (buf is NULL or buf+len has an integer overflow), return 0.

       Otherwise, return 1.

rangecheck(3)

                                                                                               range_validbuf(3)

#include<libowfat/rangecheck.h>

       int range_validbuf(const void* buf,size_t len);